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gg aN eB 

January 1960 

ed Mouth Mandibular Nerve 
ock: A New Technique... .10 

Forceps-Fixator Exodontic 
OE .vccseveesesesseale 

ical Applications of Occlu- 
mn and Articulation ........16 

Comparative Fermentation 
f Polyhydric Alcohols in Sa- 
va From Caries Susceptible 

d Nonsusceptible Mouths. .26 
NO TOD oc csveecees cam 

ical and Laboratory 
SE oe 40 weneed as eee eee 

icine and the Biologic 
EE itniseer<00 serene 

ct SEE UET Tee. 

‘A Complete Table of Contents 
Appears on page 9) 

Cover Illustration—V azirani 
article, page 10 




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. _ 


Vol. 66, No. 1 


Registered in U.S. Patent Office a iA NU. ARY 1960 

Closed Mouth Mandibular Nerve Block: A New Technique 
Sunder J. Vazirani, D.D.S., M.S. 10 

Staining of Teeth (An Abstract) 13 


r 4 

A Forceps-Fixator Exodontic Technique 

About Our Raphael Escoe, B.S., D.D.S. 14 

_— ; Clinical Applications of Occlusion and Articulation—Part One 
Sunper J. Vazirani, D.D.S. (University o 
Bombay, College of Dentistry, 1952), M.S. Leo Stoll, D.D.S. 16 
(University of Illinois) was until recently 

ber of the faculty of the University of , : : , , 
Tlinois Research aa Educational ard The Comparative Fermentation of Polyhydric Alcohols in Saliva 

He is now practicing dentistry in his native From Caries Susceptible and Nonsusceptible Mouths 

city, Bombay, India. Doctor Vazirani adds 

to his contributions to dental literature, Donald E. Shay, Ph.D. 26 
presenting in the current issue CLOSED 

Mourn MAnprsutar Nerve Brock: A New 

TECHNIQUE. The Editor’s Page - 31 

RaPHAEt Escoer, B.S. (City College of New 
York, 1948), D.D.S. (New York University Clinical and Laboratory Suggestions 32 

College of Dentistry, 1953) is a general P , 
Ties ont ten heen @ enntiiiater te 1, Locating a Submerged Root. 2. Removing Denture Teeth. 3. Depth- 

Diczst since 1956. This month he presents indicator for a Periodontal Pocket. 4. Securing Baseplates to the 
A Forceps-Fixator Exopontic TECHNIQUE. Model. 5. A Mechanical Stop for an Endodontic Instrument. 6. Re- 
moval of Alginate Impressions. 

Leo Stott, D.D.S. (New York University 

College of Dentistry, 1931) is engaged in _ : ; . 

the general practice of dentistry. He has Medicine and the Biologic Sciences 34 
devoted thirty-two years to research in the 

field of occlusion and articulation and is 

well known as an authority on these sub- Contra-Angles 4l 
jects. In this issue Doctor Stoll presents the 

first of a series of seven articles which ap- 

pear under the general title of CLINICAL 




Donatp E. Sway, B.S. (Lebanon Valley 
College, 1937), M.S. (University of Mary- 
land, 1938), Ph.D. (University of Maryland, 
1943) has been a member of the faculty of EDWARD J. RYAN ‘ B.S., D.D.S., Editor 

the University of Maryland Dental School 
since 1945 and has published two books as WANDA T. PICKARD, B.A., Assistant Editor 

well as 27 articles reporting the results of 708 Church Street, Evanston. Illinois 
his varied research projects. Doctor Shay . , 

publishes in picest for the first time in the 
current issue. His title is THE COMPARATIVE 

7 Geiek: Mies Scene Memeeeneen aim Copyright 1960 by Dental Digest, Inc. See page 6 for subscription data, etc. 

NONSUSCEPTIBLE MourTHs. The magazine is mailed on the fifteenth of the month of issue. 



Mandibular Nerve Block: 

A New Technique* 



Great advances have been made 
toward the achievement of pain- 
free dental surgery, and anesthe- 
siology has become indispensable 
in the practice of modern den- 
tistry.- Anxiety, apprehension, 
tenseness, and fear of pain, how- 
ever, are common subjective 
symptoms which keep the patient 
from availing himself of dental 
care. Fear of pain is still the most 
important problem in the prac- 
tice of dentistry and is the major 
preoccupation of most dentists.’ 
The step-by-step technique for a 
closed mouth mandibular nerve 
block demonstrated in this arti- 
cle was developed at the Univer- 
sity of Illinois, has been adopted 
by the author, and has been used 
on 3,092 oral surgery cases at the 
Research and Educational Hos- 
pital Clinics of the University of 
Illinois. A five-year clinical study 
reveals this procedure to be a 
simplified, atraumatic, direct ap- 
proach to anesthesia; it has been 
well accepted by patients and is 
especially suitable to children. 

General Considerations 

New anesthetic agents, adjuvants, and 
new techniques are being introduced 
constantly in order to provide opti- 
mum anesthetic management for the 
patient. In this field pharmaceutical 
research laboratories and surgeons 
have played a major role by provid- 


D.D.S., M.S., Bombay, India 

ing more effective agents and refined 

Common Problem in Anesthetiza- 
tion of Lower Jaw—Every dentist 
who has attempted to anesthetize a 
lower jaw with nerve-blocking in- 
jections knows the difficulties en- 
countered in completing this pro- 
cedure. The common problem is the 
pain which may be produced by the 
injection itself. 

New Technique Introduced—To 
enable the dentist to make an inferior 
alveolar nerve injection with ease 
and the least discomfort to the pa- 
tient, a new modified closed mouth 

technique, suggested by anatomic 
landmarks, has been indicated as 

having definite advantages over the | 
conventional methods employed.'* | 

*Presented before the Centennial Meeting of | 

the American Dental Association, 
September 1959. 

New York, 

1Monheim, L. M.: Local Anesthesia and Pain | 

Control in Dental Practice, St. Louis, The C. V. 
Mosby Co., og 

2Vazirani, S J.: General Anesthesia Training 
and Teaching. J; Am. D. Soc. Anesthesiol. (Feb. 

ruary) 1958. 
8Chaikin, L., and Rubin, B.: Mandibular An. 

esthesia: A Simplified Technique, JADA 53:675 

Mandibular | 
Science, p. 181 (March) | 

(Dec.) 1956. 
4Ekmanner, S., and Persson, H.: 
i Digest Dent. 

5Nevin, H. R.: Mastering the Mandibular In- 
ogg Bo er New York Novocol Chemical 

Wieg. as, : New Method of Block Anes- 
thesia, AKDA 3 543 “(Nov.) 1956. 
evin, M., and Puterbaugh, P. G.: Conduc- 
tion, Infiltration and General Anesthesia in Den- 
tistry, New_York, Dental Items Interest, 1948. 
8Seldin, H. M.: 

Febiger, 1947. 

_ Lateral 
" Blerygoid m. 

nerve & artery 

Buccinator m. & nerve 

The diagram illustrates boundaries of the pterygomandibular space. 


Dee peat ee 

Practical Anesthesia for Den- | 
tal and Oral Surgery, Philadelphia, Lea and 


Lateral pterygoid m. 

_-insertion 3 
2 a-~.,_ ga Temporalis m 
- €e\ insertion “ 
, ‘\ Pass . 
Styloid_ }ss, = an 

process |= \(\---“Upper teeth, 

Lingula~f-X \ — 
Mandibular <> VOR 
foramen ee Ba ye 
ye Nie % 
Medial pterygoid m. cae 

P \ 
Needle pierces 
buccinator m. 





The medial surface of the mandible reveals the mandibular The diagram demonstrates important landmark and site of 

sulcus and surrounding muscle attachments. 

the mandibular foramen. 

A Nerve Block 

Regional analgesia or nerve-block- 
ing has assumed a paramount posi- 
tion in achieving mandibular anes- 
thesia. In regional anesthesia, a solu- 
tion of a drug is deposited into the 
immediate neighborhood of a select- 
ed sensory nerve and by direct ac- 
tion on the nerve fibres, blocks trans- 
mission of impulses from the region. 
In other words, the deposition of the 
anesthetic agent in the vicinity of the 
nerve is sufficient to produce deep 
anesthesia.! With this type of anes- 
thesia the mandible or surrounding 
parts of the mandible can be rendered 
insensitive to pain by an injection to 
the inferior alveolar, lingual, and 
long buccal nerves. 

Anatomic Considerations 

The mere knowledge of the struc- 
tures of the oral cavity is not suffici- 
ent; the operator must know exactly 
the site and relation of the various 
structures through which the needle 
must pass in order to reach its proper 
point of destination. 

Ideal Site—To anesthetize the in- 
ferior alveolar, lingual, and long buc- 
cai nerves, the pterygomandibular 
space is the ideal site to deposit the 
anesthetic agents.”*:® The coopera- 
tion of nature is remarkably demon- 
strated by the formation of this tri- 

*Sicher, H.: Oral Anatomy, St. Louis, the 
C. V. Mosby Co., 1952, p. 412. 


angular space. It is almost as though 
this space has been created for the 
purpose of a nerve-block. 

Solution Readily Absorbed—It is 
seen that the mandibular sulcus is 
devoid of muscles on the inner sur- 
face of the ramus and the space is 
filled with loose connective tissue, in 
part of the alveolar and adipose va- 

riety, which acts as an excellent 
sponge for the absorption and diffu- 
sion of the anesthetic solution. 

The Pterygomandibular Space: 
This is a well-defined triangular space 
between the mandibular ramus and 
the pterygoid muscles (Fig. 1). Its 
lateral wall is formed by the ramus 
of the mandible, its medial wall by 

Auriculotemporal n. 
Lateral pterygoid m. 

Inf. alveolar 
art. & nerve 

Medial - 


| | Sphenomandibular 
' sligament 

Contents of the pterygomandibular space are shown in this diagram (dis- 
sected from rear). 


the medial pterygoid muscle and its 
roof by the lateral pterygoid muscle.® 

The Mandibular Sulcus: The area 
around the mandibular sulcus is free 
of any muscle attachments (Fig. 2). 
Only the following muscles are at- 
tached around the area: (1) The la- 
teral pterygoid muscle into the neck 
of the condyle, (2) the temporal into 
the coronoid process, and (3) the 
medial pterygoid into the inferior 
angle of the ramus. 

Site of Mandibular Foramen: The 
mandibular sulcus reveals a promi- 
nent mandibular foramen through 
which the inferior alveolar nerve and 
artery enter into the inferior alveolar 
canal (Fig. 3). It is situated about 
the center of the inner surface of the 
ramus and lies in the extension of 
the occlusal plane of the molar teeth. 
This is an important landmark but 
varies in each case. On the antero- 
medial side of the mandibular fora- 
men, there is a bony projection, the 
lingula. It affords attachments for the 
sphenomandibular ligament. 

Contents of the Space: The main 
structures are the inferior alveolar, 
lingual, and long buccal nerves and 
the inferior alveolar artery and veins 
(Fig. 4). The sphenomandibular liga- 
ment is in the central part and is at- 
tached to the lingula. The mandibular 
foramen also lies in the central part 
of the medial surface of the ramus. 
Otherwise, the space is composed of 
loose connective and fatty tissue, but 
it is free of muscle attachments. 

Closed Mouth Technique 

The point of needle insertion has 
always been a problem and this modi- 
fied technique of the inferior alveo- 
lar nerve injection can be success- 
fully accomplished by completing the 
following steps (Figs. 3, 5, and 6): 

a) Landmark: Since the mandibu- 
lar foramen has to be used as a 
landmark for the injection to the in- 
ferior alveolar nerve, it becomes 
clear that this injection has to be 
done as close to the plane of the 
mandibular foramen as possible. 

b) Site of Puncture and Direction 
of Insertion: The gingival margins 
of the upper molar teeth will serve 
the operator as a clinical guide and 
the pterygomandibular fold will serve 


De | 
Final position of needle for blocking the inferior alveolar nerve. Note that the 
needle should be placed parallel to gingival margins. 

as a landmark for needle insertion 
(Fig. 3). This fold gives rise to 
fibres of the buccinator muscle an- 
teriorly. This is an ideal site and 
landmark for needle puncture, for 
the needle will be 0.5 centimeter 
above the mandibular foramen. 

c) Actual Injection: 1. With the 
patient’s mouth fully closed or in the 
rest position (Fig. 6), the cheek 
should be gently stretched laterally 
so that the needle can be placed paral- 
lel to the gingival margins of the up- 
per molar teeth or the maxillary al- 
veolar ridge in the edentulous jaw. 
The two-inch, 25-gauge needle, as it 
is inserted into the pterygomandibu- 
lar fold, passes successively through 
the three layers of the sheet, namely, 
in order, (1) the mucous membrane, 
(2) buccinator muscle, and (3) buc- 
cal aponeurosis. 

2. There is no marked muscle re- 
sistance and as the needle glides into 

the pterygomandibular space, it 
creates little or no pain because of 
the absence of terminal nerve end- 
ings in adipose tissue. 

3. The anesthetic solution should 
be released drop by drop as soon as 
the mucous membrane is punctured. 

4. The needle should be inserted 
into the tissue approximately 1.5 
centimeters (the operator should 
use his own judgment as each case 
varies) and the anesthetic solution is 
deposited slowly into the pterygo- 
mandibular space. 

D. Diffusion of the initially inject- 
ed solution will also anesthetize the 
lingual and long buccal nerves. Even 
if the anesthetic agent is deposited 
away from the inferior alveolar nerve, 
again, by diffusion and gravitation 
it will reach the main trunk and will 
promptly anesthetize these filaments, 
thereby completing anesthesia. 

d) It has been pointed out that the 







1) When a conventional method 
has failed. 

2) For the patient who has a tris- 
mus or ankylosis of the jaw. 

3) In the presence of an acute or 
chronic infection in the submandibu- 
lar space region. 

4.) For patient with facial fractures 
involving the mandible and maxilla. 

5) In the case of the patient who is 
tense, nervous, or apprehensive. 

6) A child patient. 

| oe Contraindications 
6 | a 1) In the presence of an acute or 

ae ” chronic infection in the pterygoman- 
dibular space area. 

6. 2) In the case of inadequate knowl- 
Clinical view illustrates the exact position of the needle in the pterygomandibu- edge of the pterygomandibular space 
lar space. Note that the inferior alveolar nerve is medial to the needle. and surrounding structures. 

This is a new closed mouth mandi- 
3) It avoids interference with the 

ramus is not continuous in a straight 
line with the body of the mandible, 
but joins it at an angle. Thus the 
point of the needle will be away from 
the bone for a considerable distance.’ 
The author suggests that the needle 
has to be maneuvered so that it glides 
along the pterygomandibular -space 
and medial to this space. | 

Advantages of Technique 
1) The technique is simple and 

2) It avoids trauma to the inferior 

alveolar nerve, artery, and veins. 

styloid process. The skeletal material 
may be examined with the styloid 
process intact and the conventional 
method tried. 

4) Trauma to the pterygoid mus- 
cles is avoided. 

».°5) Extra néedle punctures are elim- 

6) The incidence of broken needles 
is extremely low. 

7) The technique is ideal for a 
child patient. 

8) It is far less painful than con- 
ventional methods. 

bular nerve block technique based on 
fundamental anatomic landmarks of 
the pterygomandibular space region. 
Technically it is a less complicated, 
painless, and direct approach to an- 
esthetization of the inferior alveolar, 
lingual, and long buccal nerves. The 
author suggests that if the operator 
fails to obtain the desired results with 
the conventional method he may suc- 
ceed with this new technique. With 
this technique anesthesia was success- 
ful 95 per cent of the time. : 

Arthur House 
11 Cooperage Road 

Staining of Teeth 


A layman has been told by a promi- 
nent pediatrician and a dentist 
that multiple-vitamin preparations 
could cause staining of teeth in 
young children. The dentist ad- 
vised use of preparations contain- 
ing vitamins A, D, and C only in- 
stead of those containing the vita- 
min B-complex. The child has teeth 
that look iron-stained, though she 
has never taken iron preparations. 


Apparently there are no _pub- 
lished reports that associate mul- 
tiple-vitamin preparations with 
staining of teeth. The materials 
usually present in vitamin-B com- 
plex preparations for pediatric use 
would not act as chemical stains for 
the tooth surfaces. It is extremely 
difficult to stain dental enamel. even 
with histological dyes. Intrinsic 
green staining of enamel has been 

reported in association with a his- 
tory of neonatal jaundice. The 
question notes the relationship be- 
tween iron compounds and dental 
stain. There is also a possibility 
that the observed condition may be 
due to the action of chromogenic 
bacteria. Such factors may bear 
further investigation in this pa- 

Adapted from Questions and An- 
swers, Journal of the American 
Medical Association 171:1626 
(Nov. 14) 1959, | 



Exodontie Technique 

Massena, New York 


The instrument described in this 
article is a device evolved by the 
author which facilitates the ex- 
traction of teeth. li is a useful 
adjunct to the forceps. Among 
its many advantages are the facts 
that root fracture is avoided and 
hand fatigue is decreased. The 
technique involved in the appli- 
cation of the device is described 
in detail. 


The Escoe Fixator consists of a screw 
and a large knurled knob. The screw 
is placed through holes drilled in the 
handles of an extracting forceps 
(Figs. 1A and 1B). Any means of 
securely locking the forceps to the 
tooth may be adopted. 


The device creates an intimate, in- 
tegral union between the forceps and 
the tooth by mechanical means.* 

Technique Employed 

The following steps should be 

(1) Free the neck of the tooth of 
gingiva (a sharp straight elevator, or 
scalpel may be used). If it seems 
necessary chip away some bone so 
that ideal beak placement may be 
made on a sound root. 

1Archer, H. W.: A Manual of Oral Surgery, 
see's 2, Philadelphia, W. B. Saunders Company, 

Belper. ov The ae and Technique of 
the Removal of Teeth. 8th aes Brooklyn, 
ad York, a Ttems of of Interest Publishing 
ompany, 1951, pp. 105-11 

sibid page 108. 


(2) Ideal beak placement includes 
the following :? 

a) Beaks placed in the long axis 
of the tooth. 

b) Both beaks at the same hori- 
zontal level. 

c) Beaks as close to the apex as 
tissues allow. 

(3) When ideal beak placement is 
achieved on the sound root the knob 
is tightened as far as possible using 
hand pressure. The possibility of 
breaking the tooth with the use of 

the screw® is extremely remote. 

(4) The forceps may be released 
from the hand at this time and will 
retain position on the tooth. The for- 
ceps may be released at any time to 
rest the finger tips and evaluate the 
operative situation (Fig. 2). 

(5) Using the finger tips the tooth 
is carefully luxated (Fig. 3). 

Luxation Procedure 
A) Repeated luxations are made 
over extremely small arcs. Luxation 

‘So. S526 
, 1 


Hi hut 


hililili hla 



The Escoe Fixator showing: screw, knurled knob (nut), anatomic forceps with 
holes bored in handles for the screw. (Scale is in inches.) 


The parts assembled. (Scale is in inches.) 










Forceps may be released from the hand 
and will retain position on the tooth. 

The tooth is carefully luxated using the 
finger tips. 

is buccolingual and/or rotary de- 
pending on the anatomy of the tooth 
(pre-extraction x-ray) and the mo- 
bility of the tooth as detected by the 
finger tips. 

B) No traction is employed until 
the tooth is fully mobile. In cases 
where it is desired to section a tooth 
the mobile fragments are easier to 

C) It is unnecessary to apply force 
toward the apex to loosen teeth. 

Occasionally in the process of ex- 
traction the forceps will loosen 

slightly (travel of beaks toward 
apex). When this occurs a few more 
turns may be taken on the screw. In 
cases where the root is conical the 
tooth may often be delivered using 
the screw only. 

Main at Water Street 


Conventional, Standard Forceps 

Escoe Fixation Technique 

Application of Force 

Primitive: All force must be trans- 
mitted through a clenched fist. 

Delicate: Force is applied with the 
finger tips which feel the mobility of 
the tooth easily. 

Operator Fatigue 


Great: Can not pause to rest without 
removing the forceps. 

Minimum: Can pause to rest the fin- 
ger tips while forceps placement is 
held constant. 

Is the extraction subject to 
calibration? (Automation) 

No. Force depends on the psychology 
and physiology of the individual ex- 
odontist. Governed by human factors, 
mediated through a clenched fist. 

Yes. Measured mechanical forces can 
be applied. An extension may be 
welded to the handles of the forceps 
and force applied to this. Absolute 
mechanical control of direction, mag- 
nitude, frequency, and kind (static 
loading vs. dynamic blows) of lux- 
ating force is possible. 

Wound Healing 


Root Fracture 

The same 



Patient Reaction 

Accept standard technique 

Seldom notice variation in technique 

J\NvARY 1960 

Clinical Applications 


LEO STOLL, D.D.S., Woodmere, Long Island, New York 

Balance in the occlusion of the 
teeth which is in harmony with 
the articulation of the jaws is 
generally regarded as desirable 
and essential for the normal 
physiology of the human masii- 
catory apparatus. There is a wide 
difference of opinion, however, 
concerning much of the basic 
theory and the mechanical meth- 
ods for applying the theory to 
clinical practice. This is one of 
the most controversial problems 
in dentistry. It has been the ma- 


A front view of the skull and 
mandible showing the geo- 
metric analysis of the shape 
and form of the structures 
of the masticatory machine. 
They conform in a general 
way to a triangular segment 
of a sphere with the center, 
C, roughly in the region of 
the frontal bone. 


jor interest of the author for 
more than 32 years during which 
a method was developed for 
using the maxillomandibular re- 
lations of casts or appliances 
mounted on. an articulator de- 
termined by interocclusal “‘bite’’ 
records obtained from the pa- 
tient to duplicate a variety of es- 
sential recorded maxillomandi- 
bular relations. These relations 
are used as an effective substitute 
for the dispositions and/or move- 
ments of the mandible as regu- 
lated by the temporomandibular 

articulations. Clinical application 
of this method was found useful 
for study, diagnosis, treatment 
planning, and execution of pro- 
cedures involving balanced occlu- 
sion of the teeth in harmony with 
the articulation of the jaws. 
The seven articles in this se- 
ries of which this is the first, pre- 
sent a discussion of some of the 
theoretical principles evolved, a 
description of the mechanical 
means and techniques developed 
for applying these principles, 
and a description of the method 
used in applying the techniques. 

Because the correct interpretation of 
a statement frequently depends upon 

the precise meaning of critical terms, § 

the following definitions are given 
for the terminology employed in these 

articles. The list is not intended as a | 

complete glossary of terms associated 
with occlusion and articulation. 

Occlusion—The contact relation- 
ship of the opposing teeth when the 
jaws are occluded, that is, closed 
against each other. 

Balanced Occlusion—The equal 

distribution, throughout the entire 
dentition, of the occlusal contacts of 
the opposing teeth of the occluded 
jaws, the contacts being in harmony 

with the articulated occluded maxillo- § 

mandibular relations of the jaws and/ 

or the occluded relative movements ! 

of the mandible with respect to the 
maxilla, as regulated by the patient's 
temporomandibular articulations. 
Centric Relation: The occlusion of 
the teeth in their “centric” relation- 
ship is considered to be balanced if 
the contact relationships of the cusps 


ie ann tian’ => of — noe —_~ 





Op id 

of the teeth are properly related ana- 
tomically to the fossae and grooves 
of the opposing teeth so that when 
force is applied to the jaws in centric 
relation all lateral displacing forces 
resolved by the inclined planes of 
the cusps of the teeth are neutralized. 
If this interrelationship between the 
cusps and the fossae and grooves of 
the opposing teeth does not exist 
when the opposing jaws are in cen- 
tric relation, the occlusion of the 
teeth is not considered to be balanced, 
regardless of the equality of the dis- 
tribution of the occlusal contacts. 

Zero Cusp Inclination: With flat- 
cusped artificial teeth having a zero 
cusp inclination, the cusps of the op- 
posing teeth may make balanced con- 
tact with each other. In this case 
there will be no lateral displacing 
forces generated when force is ap- 
plied to them by the jaws. 

Occlusion in Balance: Regardless 
of the nature of the cuspal anatomy, 
the occlusion of the teeth in centric 
relation, or so-called centric occlu- 
sion, is in balance when the sum to- 
tal or resultant, of all lateral dis- 
placing forces generated when force 
is applied to the jaws in this rela- 
tionship are equal to zero. 

Contact Relationship During Man- 
dibular Movements: During the oc- 
cluded mandibular movements rela- 
tive to the maxilla, to or from their 
centric relation, the occlusion is con- 
sidered to be balanced and in har- 
mony with the articulations of the 
jaw if the contact relationships of the 
cusps of the opposing teeth are main- 
tained throughout the entire dentition 
during the mandibular movements. 
This balance can exist only if all the 
inclined planes of the cusps of the 
opposing teeth are physically in har- 
mony with the regulation imposed 
upon the mandibular movements by 
the temporomandibular articulations 
of the patient. 

Articulation—The jointed maxillo- 
mandibular relations and/or move- 
ments of the mandible relative to the 
maxilla, as determined by the con- 
strained disposition and/or move- 
ments of the mandibular condyles in 
the temporomandibular articulations 
are an expression of the physiology of 
the articulations. 


A side view of the skull and mandible showing the geometric analysis of the 
structures of the masticatory machine. They conform, in a general way to a 
sphere with the center, C, roughly in the region of the frontal bone. The occlusal 
surfaces of the teeth, S, closely conform to the surface of the sphere. Also shown 
is the hinge-axis center, C’, through which the mechanical hinge-axis of the 
mandibular lever passes and around which the mandibular hinge-like rotation R, 

takes place. 

The principles of the spherical theory of occlusion and articulation were 
based on this geometric analysis of the structures of the masticatory machine 
and particularly on the theory that the occlusal surface of the teeth conforms 
to the surface of approximately a four-inch sphere. The cardinal error of the 
theory, however, was the complete disregard of the function of the mandibular 
lever, as it is regulated by the articulations which connect it to the skull. 

Comment—Occlusion and articula- 
tion have distinctly different mean- 
ings. The two words are often im- 
properly exchanged to mean the same 

Occlusion: refers to the contact re- 
lationship of the cusps of the teeth 
when the jaws are occluded. 

Articulation: refers to the jointed 
relative dispositions and/or move- 
ments of the jaws, as regulated by 
the temporomandibular articulations. 

Closely Related: While occlusion 
and articulation are distinct entities, 
they are intimately related to each 
other when the problem of balance 
is in question. Balanced occlusion of 

the teeth, in a complete sense, cannot 
exist without an intimate harmonious 
relationship between the anatomy of 
the teeth and the physiclogy of the 
articulations of the jaws. 

Centric Relation So-called “Cen- 
tric’—The most retruded unstrained 
disposition of the mandible relative 
to the maxilla when the jaws are oc- 
cluded at a particular dimension be- 
tween the occluded jaws. This dimen- 
sion is usually determined by the con- 
tact of the opposing teeth or their 
proper substitutes. This will be more 
clearly defined when the vertical di- 
mension is discussed. | 

Determination of Position: 




3A and 3B. 
A front view and a side view of the skull and mandible 
showing the general direction of a force, F, toward the 
point, C, in the general area toward which the resultants 
of the masticatory forces are directed by the mandibular 
lever when it acts against the skull. The long axes of the 
teeth are roughly coincident to the vectors of the forces and 

directed toward the structural center. This permits the teeth 

to offer the greatest resistance, without displacement, to the 
forces exerted upon them. The curve of the occlusal sur. 
faces is not accidental. It is a structural necessity for the 
efficient function of the masticatory machine. This princi- 
ple is utilized in the arrangement of the teeth when they 
are altered or replaced. 

most retruded disposition of the man- 
dible relative to the maxilla is de- 
termined by the most retruded un- 
strained disposition of the mandibu- 
lar condyles within the temporoman- 
dibular articulations. This is the neu- 
tral occluded maxillomandibular re- 
lation from which all eccentric oc- 
cluded maxillomandibular relations 
and/or mandibular movements rela- 
tive to the maxilla are reckoned. 
Relationship may be _ Incorrect: 
Under certain conditions, an appar- 
ently correct centric relation as re- 
corded in the patient may actually be 
an incorrect relationship with the 
mandibular condyles in a strained 
position within the articulations. In 
many orthopedic procedures involv- 
ing “repositioning of the mandible,” 
as for instance procedure for the re- 
lief of temporomandibular disturb- 
ances, the recorded centric relation 
as defined here may be arbitrarily 
altered in order to relieve the unap- 
parently strained disposition of the 


mandibular condyles in the articula- 

Lateral Mandibular Movements: 
The commonly accepted definition for 
centric relation includes the phrase 
“from which lateral movements can 
be made.” This would seem super- 
fluous when the condyles are in their 
unstrained position in the articula- 

Gothic Arch Tracing: Lateral man- 
dibular movements are clinically used 
for making a gothic arch tracing, the 
apex of which is used for determining 
the most retruded disposition of the 
mandible in relation to the maxilla. 
Properly used, the tracing is an ex- 
cellent method for making this de- 
termination. The centric relation, 
however, as determined by a gothic 
arch tracing can be a strained rela- 
tion. The author prefers to obtain this 
relation digitally even though the 
method can be subject to considerable 

Centric Occlusion—The contact re- 

lation of the opposing teeth when the 
jaws are occluded in their centric re- 
lation. Centric occlusion is consider- 
ed to be correct and balanced when 
the contact relationship of the cusps, 
fossae, and grooves of the opposing 
teeth are properly interrelated to each 
other, as previously described, and in 
harmony with the centric relation of 
the jaws. It is incorrect when they 
are not so related. Balanced centric 
occlusion of the teeth and centric re- 
lation of the jaws must coincide if 
centric balance in a complete sense 
is to exist in the masticatory appara 

Vertical Dimension—Refers to the 
degree of separation between the jaws 
when they are occluded in their cen- 
tric relation. Usually this measure- 
ment is determined by the patient's 
teeth when they are present or thei 
substitutes when they are absent. 

Cause of Faulty Dimension: ‘This 
dimension may be incorrect due to 
an excessive loss of tooth structures 


= ean. Gu a — =~ _~ —_—- —_— > om 


A, diagram of a lever of the third class. 
The power, P, is between the fulcrum, 
F, and the resistance, R. B, the diagram 
of the lever of the third class superim- 
posed on a mandible, which mechani- 
cally is a lever of the third class. 

or drifting of the teeth, or it may be 
incorrectly restored. The vertical di- 
mension is intimately related to the 
rest position of the mandible which 
it must not violate. The vertical di- 
mension must be at least a few milli- 
meters less, dimensionally, than the 
degree of separation between the jaws 
when the mandible is in rest position. 

Free-way Space: The interocclusal 
space between the teeth, when the 
mandible is in rest position, is known 
as the free-way space, and varies 
within a range of 2 to 8 millimeters 
in different patients. In any restora- 
tive procedure, the vertical dimension 
must respect this free-way space. 

The Rest Position—The postural 
disposition of the mandible relative 
to the skull when the mandible is sus- 
pended by the tonic contractions of 
the muscles acting on it to overcome 
gravity. Normally, the rest position is 
fairly constant in the patient but un- 
der certain circumstances may vary 
within small limits. It is the unstrain- 
ed postural position of the mandible 
from which all functional mandibular 
movements are considered to start 
and end. 

“Bite” Record—An_ abbreviated 
term for the interocclusal wax “bite” 
record which is the record of an oc- 
cluded maxillomandibular relation as 
recorded on wax placed between the 
opposing jaws and/or teeth. 

Further Identification: The “bite” 
record is further identified by the 
nature of the occluded maxilloman- 


The gliding mandibular lever as a 
plane figure showing its two basic 
movements of rotation around its ful- 
crum, R, and translation of its ful- 
crum, T. Also shown is a resultant 
movement, M, which is a combination 
of both basic movements. The move- 
ments the mandibular lever is permit- 
ted to make are determined by the 
articulations which join the mandi- 
buiar lever to the skull. 


dibular relation of which it is a rec- 
ord, that is, centric, right or left lat- 
eral, or protrusive “bite” record. 

Clinical Use: “Bite” records are 
used exclusively in the method to 
be described for determining the 
maxillomandibular relation of the 
casts or appliances mounted on-an 
articulator in order to duplicate the 
maxillomandibular relations of a pa- 
tient as a substitute for the patient’s 
mandibular movements. 

The Human Masticatory 

The human masticatory apparatus 
may be considered to be a biologic 
machine. This discussion is concern- 
ed with the mechanics of the machine 
exclusive of the important essential 
biologic considerations. 

Definition—A machine is a com- 
bination of resistant materials having 
definite motions and capable of trans- 
mitting or transforming energy sup- 
plied to it from an external source. 
Its usefulness consists in the ability 


to alter the energy supplied so as to 
render it available for the accomplish- 
ment of a desired service. | 

A Mechanism—A combination of 
resistant materials whose parts have 
constrained movements regardless of 
energy or output of useful work is a 
mechanism. A machine is composed 
of one or more mechanisms and is a 
practical development of the latter 
when energy is in question. 

Human Masticatory Machine—This 
complex satisfies the requirements of 
the definition for a machine. Parts of 
the skull and its articulated mandible 
are the resistant structures having 
relative movement and capable of 
transmitting the energy supplied to 
it by the masticatory muscles for the 
purpose of incising, crushing, and 
grinding food. 

Movements of the Mandible—Con- 
cern is with the mechanism of the 
masticatory apparatus, specifically 
the constrained dispositions and/or 
movements of the mandible relative 
to the skull and the mechanics of the 

The gliding mandibular lever as gq 
three-dimensional structure showing 
its two basic movements of rotation 
around its fulcrum, R, and translation 
of its fulcrum, T. Also shown is a re. 
sultant movement, M, which is a com. 
bination of both basic movements. 
The mandibular condyles are the 
bearings which together comprise the 
fulcrum around which the mandibular 
lever turns. The mandibular hinge-axis 
passes through the fulcrum of the 
lever. This is a law which governs 
levers. The gliding movement of the 
mandibular hinge-axis is shown. 

articulations connecting these struc- 

Function Facilitated—The geomet- 
ric form of a sphere is structurally 
suited to facilitate the efficient func- 
tion of the masticatory machine, spe- 
cifically, the application of force 
(Figs. 1 and 2). 

Attached Parts—The opposing 
teeth. are the specialized attached 
parts of the masticatory mechanism. 
The major clinical problem in occlu- 
sion of the teeth and articulation of 
the jaws is the development of occlu- 
sal balance in harmony with the pa- 
tient’s masticatory mechanism which 
is unique for each patient. In rare 
instances, not to be discussed here, 
certain minor modifications in the 
mechanism itself must be made. 

The Mandibular Lever 

Mechanically, the mandible is a 
lever of the third class capable of 
constrained hinge-like rotational and 
gliding movements or a combination 
of these two types of movements. The 
hinge-like rotational movement is the 
primary movement of the mandibu- 
lar lever. 

Accommodating Movements—The 
gliding movements are secondary ac- 
commodating movements for shifting 
the relative disposition of the fulcrum 
around which the lever turns with 
respect to the skull. The gliding move- 
ments are also important to permit 
the scissor-like action of the man- 
dibular lever against the skull. 

Increase of Mechanical E fficiency 
—Shifting of the fulcrum of the man- 
dibular lever is necessary for increas 
ing the mechanical efficiency of the 




The underside surface view of the mandibular lever and 
the skull showing a lateral gliding mandibular movement. 
A, the mandibular lever in its “centric”? relation relative 
to the skull. B, a right lateral eccentric relation of the 
mandibular lever. For the lateral movements, one of the con- 

dyles, or bearings of the fulcrum, is relatively immobilized 
and the other condyle of the fulcrum rotates around a verti- 
cal axis in the region of the immobilized condyle. The 
specific nature of these movements is determined by the 
structure of the articulations. 

lever by placing it in the most ad- 
vantageous and convenient position 
for hinge action against the skull as 
well as to modify grinding and tritu- 
rating movements for the incision, 
crushing, and grinding of food. 

Constraint Determined by Joining 
of Structures—The temporomandibu- 
lar articulations joining these struc- 
tures to each other determine the 
character and degree of constraint 
imposed upon their relative move- 

Subject to Physical Laws—Without 
exception, the mandibular lever is 
subject to all the physical laws which 
govern levers. A lever always turns 
around an axis passing through its 
fulcrum which, by definition, is the 


support or bearing on or against 
which a lever rests or turns. 

Mandibular Condyles—Because of 
the peculiar modified U shape of the 
mandibular lever, the fulcrum, around 
which its hinge-like rotary movement 
takes place, is structurally divided 
into two bearing elements, the man- 
dibular condyles. 

Condyles Functionally United— 
These two condyles, however, are 
physically united parts of the same 
single bone, a rigid structure, and 
must be considered to be functionally 
united. Hinge-like rotary movements 
of the mandibular lever can only take 
place around an axis passing through 
both condyle elements. 

Confirmed Kinematic Principle— 

One of the condylar elements alone 
cannot serve as an independent bear- 
ing point for the lever through which 
an independent axis passes. This is 
a kinematic principle. 

Three Points Must be Known—The 
motion of a body is studied by ob- 
serving the motion of certain points 
on it. The number of points to be 
considered depends upon whether the 
body can move in any manner or 
whether its motion is limited to some 
special kind, for example, plane mo- 
tion, or rectilinear motion. In gen- 
eral, to determine the motion of a 
body completely, the motion of three 
noncollinear points on a bedy must 
be known. 

Example: If three points are fixed 


o*.0 © w= 




A diagram showing the theoretically 
possible movements of each of the 
mandibular condyles, or terminal ear. 
ings of the fulcrum of the mandibular 
lever. Each of the condyles is capable 
of rotation around three intersecting 
axes, X, Y, and Z, and translation in 
any of the three planes determined by 
these axes. The movements are limited, 
however, by the structure of the articu. 
lations. The movements of each of the 
condyles must be cooperative with each 
other, that is, a movement of one of 
the condyles must always be accom. 
panied by a compensating movement 
of the other condyle, since both con. 
dyles are part of the same mandibular 

Obviously, the movements of the 
fulcrum of the mandibular lever, col. 
lectively the condyles, is complex be. 
cause of the freedom given these move- 
ments by the structure of the articula- 
tions which join the mandibular lever 
to the skull and which regulates their 
relative movements. 


A diagram of mandibular 
- movements. A, the basic 
hinge-like rotational move- 
ment, R, and the basic 
translational gliding move- 
ment, T. B, a_ resultant 
movement which is a com- 
bination of the two basic 
movements, R plus T. The 
resultant movement of an 
incisal point I to I’, M. is 
shown with the resolved 
basic movements, R and T. 


r 4 


An enlarged diagram of the movement 
of the incisal point I to I’ in the previ- 
ous figure. The resultant movement, 
M, is shown with the resolved basic 
movements, R and T. Obviously, the 
movement of any other points on the 
mandible must be resultant movements 
of the combination of both basic move- 
ments of rotation and translation. 

on any body, it is evident that no mo- 
tion is possible unless these points lie 
in a straight line. Likewise, if each 
of the three points is moved along 
a definite path in space, any other 
point on the body will also follow a 
definite path, and constraint is com- 

Constraint in Plane Motion: When 
a body has plane motion, such as 
hinge-like motion, by the same rea- 
soning it will be seen that it is only 
necessary to control the motion of 
two points, not in a straight line per- 
pendicular to the plane of motion, in 
order to secure complete constraint. 

Possible Rotational Points: If the 
mandibular lever were to be consid- 
ered as a body not having any width 
or thickness, one of the two points 
through which an axis for hinge-like 
rotation passes could be one of the 
condylar bearings which is known to 
be fixed in its relation to the lever. 
The other point which can rotate 
around the fixed point could be in 
the incisal region of the lever. 

JAN: ARY 1960 

¢—B —'tA> 


A diagram of the cross section of opposing molars showing the functional range 
of the occluded mandibular movement, A, and the nonfunctional range of oc- 
cluded mandibular movements, B. Only the occluded mandibular movements 
within the functional range are of any importance from the standpoint of bal- 
anced occlusion and articulation. 


4 Ale. 3 4 


A diagram of the side view of opposing bicuspids showing the functional range 
of occluded mandibular movement, A, and the nonfunctional range of occluded 
mandibular movement, B. 


Third Point Necessary—The man- 
dibular lever, however, does have 
width and thickness. A third point 
must be engaged in order for hinge- 
like rotation of the lever to place. Any 
third point on the lever which is 
known to be fixed would have to be 
on the same straight single line or 
axis, passing through the first fixed 
point in question and the two fixed 
points, or condylar bearings, must be 
on a single straight line perpendicular 
to the plane of hinge-like motion. The 
straight line passing through these 
two fixed points is called the man- 
dibular hinge-axis. This will be illus- 
trated later when the mandibular 
hinge-axis is discussed. 

Mandibular Gliding 

The same kinematic principle for 
the determination of motion is ap- 
plicable for the study of the gliding 
movements which shift the fulcrum 
of the mandibular lever and the axis 
around which the mandibular hinge 
movement takes place. 

Movements Around Hinge-Axis— 
Since the movement of three noncol- 
linear points on a body can determine 
its: motion, and since two of those 
points are the points through which 
the mandibular hinge-axis invariably 
passes, it is evident that all the man- 
dibular movements other than the 
hinge movement around its hinge- 
axis, (the gliding movements) can be 
considered to be movements of the 
hinge-axis itself. | 

Translational or Rotational Move- 
ments—The gliding movements of the 
mandibular hinge-axis are more spe- 
cifically described as_ translational 
and/or rotational movements of the 
two points through which the hinge- 
axis passes, or in effect, translations 
and/or rotations of the mandibular 
hinge-axis itself. 

Possible Combination of Move- 
ments—In view of the above, all man- 
dibular movements may, in effect, be 
considered to be rotational move- 
ments of the mandible around its 
hinge-axis, gliding movements of the 
mandibular hinge-axis itself, or re- 
sultant movements which may be any 
combination of the rotational and 
gliding movements. 



A diagram showing a right lateral eccentric maxillomandibular relation which 
is the result of a right lateral mandibular movement within the functional range 
of occluded mandibular movement. Eccentric relations of this nature are used 
in the method and technique for establishing balanced occlusion and articulation, 


A body has constrained motion 
when it is so guided by contact with 
other bodies, or by external forces, 
that any point on it is obliged to move 
in a definite path. Partial constraint 
exists when the movement of a body 
is only restrained in certain direc- 
tions in order to move within cer- 
tain boundaries. 

Partial Constraint Improved—The 

temporomandibular articulations im. 
pose partial constraint upon the 
movements of the mandibular con- 
dyles and to the extent of this con- 
straint regulate the mandibular move- 

Structure of Articulation Related 
to Constraint—The constraint im- 
posed upon the movements of the 
mandibular condyles is determined 
by the structure of the articulations 
which mechanically permit the con- 


A diagram of a functional occluded right lateral mandibular movement. The 
movements of the points R to R’, I to I’, and L to L’ are shown. For the range 
of movement considered, the points may be considered to be straight line move- 
ments even though they are theoretically curved movements. 


- —<— —_— sg ©, 

a. aie « 


~~ A’ 




A diagram showing three arcs A, A’, 
and A” of circles drawn respectively 
from the centers, C, C’, and C”’. The 
arcs are superimposed in the area of 
H. Practically, for the range indicated 
by H, the arcs may be considered to 
be straight lines. Point paths of move- 
ment within such a limited range of 
movement, as indicated by H, may be 
considered to be straight line move- 
ments, regardless of what they are 
theoretically. The point paths of the 
cusps of the teeth within the function- 
al range of occluded mandibular move- 
ments may be considered to be short 
straight line movements. When the 
cuspal inclinations of the cusps of the 
teeth are adjusted, this practical con- 
cept is utilized. 

dyles to make hinge-like rotational 
and gliding movements; or as is most 
usual, any resultant which is a com- 
bination of both the hinge-like rota- 
tional and gliding movements. 

. Permitted Movements are Unique— 
The specific character of the permit- 
ted movements are unique for each 
articulation. The combined synchro- 
nized movement of both mandibular 
condyles is likewise unique for a par- 
ticular patient. 

Description of Gliding Movements 
—For convenience, the gliding move- 
ments of the mandibular condyles per- 
mitted by the articulations are de- 
scribed as being either right or left 


lateral or protrusive movements. 

Protrusive Movements—For these 
movements the gliding movements of 
each of the condyles are more or less 

Lateral Movements—For _ these 
movements one of the condyles is 
more or less stabilized for rotation 
around a vertical axis in the region 
of that condyle while the other con- 
dyle makes a compensating rotational 
gliding movement. 

Numerous Combination Move- 
ments—An infinite variety of inter- 
mediate resultant movements which 
are a combination of the protrusive 
and lateral gliding movements can 
also be made. 

Movements Regulated by Articu'a- 
tion—All mandibular movements are 
regulated by the constraint imposed 
upon the mandibular condyles by the 
articulations. Since the mandibular 
condyles are considered to be the 
bearing points of the fulcrum of the 
mandibular lever through which the 
mandibular hinge-axis passes, ll 
mandibular movements may be con- 
sidered to be movements around its 
hinge-axis and/or gliding move- 
ments of the mandibular hinge-axis 
itself, as regulated by the articulations 
of the subject. 

Occluding and _  Nonoccluding 
Movements—All gliding mandibular 
movements which involve a shift in 
the position of the mandibular hinge- 
axis may be classified as being either 
occluding or nonoccluding move- 
ments, depending on whether the op- 
posing teeth are in contact during the 

Convenience Movements: The non- 
occluding gliding movements are not 
concerned with balanced occlusion 
and articulation. They are merely 
convenience movements for altering 
the disposition of the fulcrum of the 
mandibular lever. 

Functional Range Limited: Of the 

which are regulated by the articula- 
tions, only that small range of move- 
ments which is limited by the contact 
of the opposing teeth in their centric 
relation to their cuspal tip-to-tip con- 
tact relationship in any eccentric re- 
lationship, or vice versa, is of any 
importance from the standpoint of 
balanced occlusion of the teeth in 
harmony with the articulations of the 
jaws. Occluded mandibular move- 
ments beyond this limited range of 
movement are not considered func- 
tionally important. 

Useful Range of Small Magnitude: 
This limited range of movement is 
considered to be the functional range 
of occluded mandibular movement. 
Because this useful range of mandibu- 
lar movement is of such a small mag- 
nitude, the actual movements of the 
cusps of the teeth may be considered 
to be small straight line movements, 
regardless of what they are theoreti- 

Effective Substitute for Actual 
Movements—These movements make 
it possible to use functional eccentric 
maxillomandibular relations, which 
are the resultants of functional oc- 
cluded mandibular movements, as an 
effective substitute for the actual 
movements for which the regulated 
mandibular movements would ordi- 
narily be used. 

Relationships Inseparable—The ac- 
companying figures illustrate the in- 
timate and inseparable relationship 
between the general shape and form 
of the structures of the masticatory 
machine and their mechanical action, 
or function. The geometric center of 
the structures and the center toward 
which forces are directed are approxi- 
mately coincidental. From an engi- 
neering standpoint, the structures are 
designed for their intended function. 

(End of Part One) 

246 Woodmere Boulevard 

occluded mandibular 

The Comparative Fermentation 


From Caries Susceptible and Nonsusceptible Mouths 

DONALD E. SHAY, Ph.D.,* Baltimore, Maryland 


Many investigators have ‘sought 
to curb caries incidence by advo- 
cating the use of substances in- 
tended to inhibit or resist the mi- 
crobial fermentation, which in 
turn decreases acid production. 
Grubb! has suggested use of the 
sugar alcohol sorbitol in oral 
preparations as this sweet poly- 
hydric alcohol is found to be re- 
sistant to attack in vitro by the 
implicated acidogenic bacteria. 

Since several polyhydric alco- 
hols are commonly used in oral 
preparations for technologic pur- 
poses, it is important to deter- 
mine their fermentability by oral 
microorganisms. The initial ob- 
servations were carried out in 
vitro. This method of testing was 
soon abandoned for the more in- 
formative in vivo method. This 
paper presents a clinical study of 
the intracarious fermentability of 

sucrose and glucose as compared 
with several polyhydric alcohols 
commonly used in oral prepara- 

Early Investigation 

Because the acid products of fermen- 
tation are of chief concern in the pro- 
duction of dental caries, it was de- 
cided to determine the in situ pH of 
the teeth both before and after the 
ingestion of these compounds. 

1. Stephan? in 1940 successfully 
used an antimony electrode for elec- 
trometrically determining the pH of 
plaque and carious material in situ. 
He was able to show that by the in- 
gestion of certain carbohydrates the 
pH of plaques and open carious le- 
sions can be lowered beyond the 
critical decalcification level of ena- 
mel, 5.5. 

2. In 1944, using the antimony 
electrode, Stephan*® found that after 
a glucose rinse the pH drop varied, 

being greatest in those cases with 
greatest caries activity. 
3. Stralforst in 1948 confirmed 

Stephan’s conclusions, using lacto- 

bacillus count as an indication of & 

caries activity. 

4. Crowley, et al.° compared the 
in vitro fermentability of sorbitol, 
glycerol, and glucose by certain oral 
microorganisms. Within a 24-hour 
period the majority of these organ- 
isms produced sufficient acid from 
glucose to decalcify the enamel. Their 
findings indicated that this result was 
not the case with sorbitol. 

*From the Department of Microbiology, Uni- 
versity of Maryland, School of Dentistry. 
Author’s Note: The assistance of J. P. Kass, 
T. C. Grubb, and M. Tabak, who have made 
valuable suggestions on the statistical interpre- 
tation of the data, is gratefully acknowledged 
and to G. P. Foley for his assistance in the 
preparation of the manuscript, acknowledgements 
are also made. 
1Grubb, T. C.: Studies on the Fermentation of 
Sorbitol by Oral Microorganisms, J. Den. Res. 
24 :31-44 (Jan.) 1945. 
2Stephan, R. M.: Changes in Hydrogen-ion 
Concentrations on Tooth Surfaces and in Carious 
Lesions, JADA 27:718-23 (May) 1940. 
8Stephan, R. M.: Intraoral Hydrogen-ion Con- 
centrations Associated with Dental Caries Activ- 
ity, J. Den. Res. 23:257-66 (Aug.) 1944. 
4Stralfors, A.: Studies of the Microbiology of 
Caries. II Acid Fermentation in the Dental 
Plaques In Situ. Compared with Lactobacillus 
Count, J. Den. Res. 27:576-86 (May) 1948. 
5Crowley, M. C.; Harner, V.; Bennett, A. S.; 
and Jay, : Comparative Fermentability of 
Sorbitol and Glycerol by Common Oral Micro- 
organisms, JADA 52:148 (February) 1956. 


Mean pH Determinations of Samples of Saliva Incubated 

Aerobically at 37° Centrigade* (98.6° Fahrenheit) 

Approx. 2 Per cent 

in Saliva 1 day 2 days 3 days 4 days 
Sorbitol tae 6.68 6.12 6.11 
Glycerin 7.31 6.93 6.53 6.51 
Sucrose 7.02 9.10 4.82 4.80 
Water** 7.32 7.04 7.26 7.39 


5 days 7 days Difference 
9.31 9.94 1.81 
5.94, 6.10 1.21 
4.80 4.90 2.12 
7.02 7.12 0.20 

*Each value represents 60 samples of saliva. 

** Water was added to equal volume. 




in v 








5. Shockley, et al.° demonstrated 
that the mixed flora of saliva had 
little tendency to ferment sorbitol 
during short periods of incubation 
in vitro. 

6. The results obtained by Fos- 
dick, et al.? substantiate those cited. 
pH determinations of the dental 
plaque were made after rinsing the 
mouth with 50 per cent solutions of 
sorbitol and sucrose. Fermentation 
by the plaque microorganisms of the 
sucrose produced a pH value of 5.38, 
whereas with sorbitol the pH value 

was 6.55. 

| Experimentation 

Grubb! found that the rate of fer- 
mentation of sorbitol was consider- 
ably less than that of dextrose and 
sucrose. In order to obtain an exact 
picture of the fermentative ability of 
related compounds, glycerol, sorbitol, 
glucose, and sucrose were employed 
in the present study. 

Slow Fermentation of Sorbitol— 
In the first series of observations 

| made on the fermentation of sorbitol 

by oral microorganisms in vitro, it 
became evident that sorbitol was fer- 
mented much more slowly than either 
glucose or sucrose. This result agreed 
with the conclusions of Grubb. The 
resulting pH of the medium in which 
sorbitol was incorporated did not 
reach the range (pH 5.5) considered 
necessary to cause enamel decalcifi- 

Sorbitol Fermenters in Saliva—A 
quantitative estimation of sorbitol 
fermenters in saliva was undertaken 
using carbohydrate-free media with 
trypticase. Each of the tested ma- 
terials was incorporated in the me- 
dium. Saliva samples were collected 
and diluted; 0.1 milliliter was streak- 
ed on the surface of the plates. The 
plates were incubated at 37° centi- 
erade (98.6° Fahrenheit) for 48 
hours. The results obtained by the 
in vitro method were encouraging 
but not conclusive. 


*Shockley, T. E.; Randles, C.; and Dodd, M. 
.: Fermentation of Sorbitol by Certain Acido- 
genic Oral Microorganisms, J. Den. Res. 35:233 
(April) 1956. 

_ ‘Fosdick, L. S.; Englander, H. R.; Hoerman, 
.. C.; and Kesel, R. G.: A Comparison of pH 
Values of In Vivo Dental Plaque After Sucrose 
and Sorbitol Mouth Rinses, JADA 55:191 
(Aucust) 1957. 

’Fosdick, L. S.; Campaigne, E. E.; and Fan- 
cher, O.: _Rate of Acid Formation in Carious 
Areas: Etiology of Dental Caries, Illinois D. J. 
10:85-95 (March) 1941. 



Average pH Readings After 2, 10, and 20 Minutes of Contact 
with Sorbitol, Glycerin, Sucrose, and Dextrose 

Time Sorbitol Glycerin Sucrose Dextrose 
0 Control 6.0 6.3 6.3 6.4 
2 Minutes 5.9 6.3 5.0 5.4 
10 Minutes 6.1 6.2 5.2 5.5 
20 Minutes 6.1 6.2 5.8 6.0 
Mean pH (Treatment-Control Time ) 
Treatment 2 Minutes 10 Minutes 20 Minutes 
Sorbitol -.02 15 16 
Glycerin -.03 -.09 -.10 
Dextrose -.93 -.9] -.36 
Sucrose -1.26 1:15 -.46 
s.d.—.40 s.d.—.40 s.d.—.4l 


Ranked* Mean pH Values 
Times 2, 10, and 20 Minutes 

2 Minutes: Sorbitol—= Glycerin <Dextrose <Sucrose 
10 Minutes: Sorbitol <Glycerin <Dextrose <Sucrose 
20 Minutes: Sorbitol <Glycerin <Dextrose —Sucrose 

* All indicated differences are significant at p 0.05. 

Average pH of 186 Teeth in 
Caries-Free Mouths 
After Rinsing AfterRinsing After Rinsing 

Before with with with 

Rinsing 3% Sorbitol 3% Sucrose 3% Glycerin 
Teeth 6.22 6.22 6.197 6.19 
Saliva 6.42 6.30 6.31 


Mean pH Determinations of 
Samples of Saliva 
Incubated Aerobically at 
37° Centigrade 

(98.6° Fahrenheit ) 

This phase of the experimentation 
was to determine the changes in pH 
brought about by inoculating samples 
of saliva into 2 per cent solutions of 
sorbitol, glycerin, sucrose, and water. 

Procedure—(1) Samples of saliva 
were collected from sixty people. (2) 
Those were divided into aliquots and 
the pH of each determined. (3) They 
were incubated at 37° centigrade 
(98.6° Fahrenheit) and pH determi- 

nations were performed each day for 
7 days. (4) To 3 sets of the same 
saliva samples, glycerin, sorbitol, 
and sucrose were added in 2 per cent 
concentrations. No artificial medium 
was used. The determinations were 
made at the same time each day to 
allow for a 24-hour incubation peri- 
od between each determination (Ta- 
ble 1). 

Study Continued—After the pre- 
liminary observations, shown in Ta- 
ble 1, the in vivo approach to the 
problem was adopted with the idea 
of taking pH readings before and 
after rinsing with the test solutions. 



AFTER 20 Mm 

1 MIN. 

‘2 MIN. 


10 MIN. 

2 MIN. 



pH 75 

70 65 

[] = OWE CaviTy 

60 55 

‘80 45 40 35 

This study was made on 36 subjects, 
routine patients of various age 
groups, who presented themselves to 
the Clinic for dental care. The ma- 
jority of these patients showed ex- 


treme caries activity. 

Carious Lesions Tested— The pH 
determinations, using antimony elec- 
trodes, were made of the carious le- 
sions of these patients rather than 


The number of carious lesion: an 
their pH values before and after 2, 10, 
and 20-minute intervals using a sorbj. 
tol rinse is shown. Approximately 84 
per cent of the cases had a pH value 
of 5.6 or above before rinsing with 
sorbitol solution. This remained the 
same 2 minutes after rinsing. At the 
10, and 20-minute intervals the num. 
ber of cases at 5.6 or above was ap. 
proximately 96 per cent. 


The same results are shown using su. 

.crose as the rinse solution. Ninety-two 

per cent were pH 5.6 or above before 
rinsing. Two minutes after rinsing 
about 6 per cent remained above a pH 
of 5.6. After 10, and 20-minute peri. 
ods approximately 10 per cent and 39 
per cent, respectively, were above the 
critical pH level of 5.5. 

of the dental plaques since it has 
been found that after the ingestion 
of fermentable substances the pH 
minimums of carious lesions are low. 
er than those of plaque material.* In 
essence this approach constitutes a 
more stringent test of fermentation. 

Method Used—(1) To measure the 
pH of the carious area the saliva 
present in the area was removed with 
the air bellows. 

(2) The cavity was not completely 
dried, only the excess saliva being 

(3) The tip of the electrode was 
inserted into the carious area and 
the pH noted. 

(4) After the initial readings and 
the times at which they were taken 
were recorded, the patient was in- 
structed to rinse his mouth for two 
minutes with 50 milliliters of the 
solution being tested. 

(5) At intervals of approximately 
2, 10, and 20 minutes after the rinse, 
additional readings were made. 

(6) Four solutions (in a 3 per cent 
concentration) were used as mouth- 
washes in this experiment: glycerol, 
sucrose, glucose, and sorbitol. 

Statistical Information 
Two hundred and three teeth were 

studied in the 36 subjects: 50 each 
for dextrose and sucrose; 51 for 
glycerin; and 52 for sorbitol. The 


per © 
of 5.4 
pH o 
34 pe 
was 1 
5.6 « 



oe TF = FT © 


The same results are shown using 
dextrose solution. Before rinsing 98 
per cent of the lesions had pH values 
of 5.6 or above. After 2, 10, and 20- 
minutes the numbers of lesions at a 
pH of 5.6 or above were 28 per cent, 
34 per cent, and 82 per cent, respec- 


The same type of observation is rep- 
resented. However, a glycerin solution 
was used as the rinse. Before rinsing, 
approximately 94 per cent had pH 
values of 5.6 or above. After rinsing 
approximately 94 per cent had pH 
ralues of 5.6 or above. After 2, 10, 
and 20 minutes the percentages of 
carious lesions that had pH values of 
5.6 or above were 88 per cent, 78 per 
cent, and 84 per cent respectively. 


average pH values with each of the 
compounds are tabulated in Table 2. 

Statistical Evaluation of 
The Data Obtained 

The data graphically represented 
in Figures 1, 2, 3, and 4 appear more 
significant when statistically evalu- 
ated. The statistical analysis is con- 
cerned with a determination of the 
significance of difference in change 
in pH (ApH) for the four solutions 
employed to rinse the mouth: sor- 
bitol, glycerin, dextrose, and sucrose. 

The unit of measurement is 


Where pHo=pH reading before 
pHt=pH reading, T minutes follow- 
ing rinse with a given solution. 

Average Change Recorded—In Ta- 
ble 3 the average change in pH is 
recorded for each of the solutions 
tested, at 2 minutes, and 20 minutes 

| after rinsing. These data are graph- 
| ically represented in Figure 5. 

Minimal Changes Recorded—This 
analysis demonstrates the superiority 
of sorbitol as the treatment which 
eflected minimal pH changes in cari- 
ous teeth. The various solutions have 
been ranked in Table 4 in respect to 
their activity for 2, 10, and 20 min- 



10 MIN 

2 MIN. 





10 MIN. 

,e ce 



2 MIN 






fi ti 


Lf i ' 

pH 75 70 6 

60 55 50 45 40 


' Lj ' Li a 


with a smaller A pH) than the right- 

sucrose, and glycerin, determinations 

utes. The symbol (=) indicates that 
the 2 solutions in question are not 
Statistically different in respect to 
their fermentative activity. The sym- 
bol (<) indicates that the left-hand 

member is fermented less (associated 

hand member. 

Caries-Free Determinations—Addi- 
tional pH determinations were made 
on 186 teeth in mouths of 7 caries- 
free patients. After rinsing the mouth 
with 3 per cent solutions of sorbitol, 

were made of the upper and lower 
teeth and the saliva. 

The results are tabulated in Table 
5. The values obtained after rinsing 
with the 3 solutions would suggest 
that in caries-free mouths the pH 

JANUARY 1960 29 


The average differences in pH values 
are shown graphically. The mean pH 
values for sucrose are -1.26, -1.15, and 
-46 after 2, 10, and 20-minute peri- 



ods; with dextrose -.93, -.91, -.36; ApH .2 
glycerin -.03, -.09, -.10 and for sorbital SORBITOL OF 
-02, .15, and .16 respectively. The A ~ 
mean pH values for the sugar alco- str 
hols, sorbitol and glycerin, are in prox- 0) ter 
imity. Those for dextrose and sucrose P 
are similarly grouped at a lower level. -.| i us 
: Pe 
° 2 ac 
changed only slightly or not at all, 
and in no case approached the critical -3 of 
level of 5.5. Additional pH readings ar 
on caries-free teeth are being made. 4 rd WW 
Summary “5 / Fi i 
1. In vivo pH readings of 203 / ne 
carious lesions made in the mouths - as 
of 35 clinical patients by using an -7 p! 
antimony electrode show that the pH la 
of the carious lesions ranged from -8 VA 
7.6 to 4.1. d 
2. The test solutions in 3 per cent -9 DEXTROSE 
concentrations were divided into 2 Y 
groups: (1) the fermentable sugars —_ ri 
sucrose and dextrose, and (2) the ani p 
more resistant polyols sorbitol and , n 
glycerin. After rinsing with these -12 SUCROSE : 
solutions the pH of the carious area 5 é 
decreased, the extent depending on -1.3 
the degree of fermentation and the . a 20 J 
subsequent production of acid. ieee ties d 
3. Averages of the in vivo pH de- g 

terminations indicate that rinsing 
with the polyhydric alcohol solutions 
did not permit the production of 
enough acids to cause a drop in pH 
below the critical level for enamel 
decalcification (5.5). 

4. After rinsing with sucrose or 
dextrose solutions, the pH values re- 
corded at 2, and 10-minute intervals 
were pH 5.5 or below. 

5. Sorbitol and glycerin were me- 
tabolized to acid in the carious lesion 

less than dextrose and sucrose were. 

6. Dextrose and sucrose showed 
significantly lower pH values than 
the other solutions for at least 20 
minutes after rinsing. 

7. Two minutes after rinsing, sor- 
bitol and glycerin were not statis- 
tically different in fermentative ac- 

8. Ten minutes after rinsing, sor- 

bitol was fermented less than glyce- 
rin; glycerin less than dextrose; and 
dextrose less than sucrose. The results 
were approximately the same after 
20 minutes. 

9. In caries-free persons there was 
little or no change in pH after rinsing 
with solution of sorbitol, glycerin, 
and sucrose. 

University of Maryland 


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The EDITOR'S Page 


Or THE two principle types of dental disease, de- 

| struction of the hard tissues has received more at- 

tention than has degeneration of the supporting 
tissues. Caries may be seen and often felt as pain. 
Periodontal disease is degenerative and is seldom 
accompanied by pain. Caries is essentially a disease 
of childhood and early adult life. It is subject to 
arrest and treatment by specific mechanical meas- 
ures. Periodontal disease is usually found in older 
persons and is not amenable to treatment by specific 
methods. The issue has been clearly stated by Flem- 
ing: “Periodontology is essentially a biological 
problem practiced in a profession that has developed 
largely along mechanical and technical lines.” 

The appalling tooth loss rate from periodontal 
disease is expressed in these stark figures by 


Williams and Henry: “Tooth mortality rate rises 
rapidly after 35 years of age, probably because 
periodontal disease becomes more generalized and 
more severe in degree by this age. By ages 45 to 51, 
50 per cent of the teeth have been lost; by age 60, 
60 per cent of the teeth; and 26 per cent of the sub- 
jects were edentulous. Despite the high prevalence 
and high tooth mortality figures noted in the investi- 
gations, only 9 per cent of all subjects examined 
were aware of the presence of periodontal disease; 
only 7 per cent had received treatment for this con- 
dition. ... 

“The prevalence of gingivitis is low at 5 years of 
age, rises sharply and rapidly to a peak at puberty 
(12 to 15 years.) A sharp rise in prevalence from 
6 to 8 years of age has been assumed to be related 
to the eruption of the permanent teeth. 

“By age 25 years, about 50 per cent or more have 
detectable evidence of periodontal disease. 

“By age 40 years, nearly 100 per cent of indi- 
viduals are affected. 

“By age 65 years all subjects exhibited general- 
ized resorption of alveolar bone.” 

Any disease that is so widespread and so relent- 
less in devastation of human tissue should receive 
more attention by basic research and more atten- 
tion from dental clinicians. Research will, we hope, 


‘Fleming, Willard C.: Proceedings of a Workshop for Teachers in Perio- 
dontology, San Francisco, The American Academy of Periodontology, 1958, 

“2Williams, Charles H. M., and Henry, Joseph: ibid., p. 71. 


uncover the multiple causes of the disease and 
suggest relationships between the causal factors. Re- 
search, however, will be without full meaning until 
the discoveries are put to clinical application. The 
treatment of periodontal disease, because the con- 
dition is so common, must be performed by general 
practitioners as well as by periodontists. As is the 
case with the other degenerative diseases, the public 
must be made aware of the complex processes in- 
volved in the disease and of the fact that only a 
dentist can treat the condition with the self-help and 
the self-discipline of the patient in matters of per- 
sonal hygiene. 

Glickman and Ramfjord* have suggested these 
subjects and “avenues worthy of further research:” 

1) Calculus: its formation, prevention, and re- 
moval by nonmechanical agents. 

2) The anatomical aspects of periodontium. 

3) Connective tissue. 

4) Wound healing in the region of the perio- 

2) The importance of the “stress” syndrome in 
the etiology and management of periodontal prob- 
lems. . 

6) The role of nutrition in periodontal therapy, 

7) Trauma from occlusion in the etiology of 
periodontal disease. 

8) The role of occlusal adjustment in treatment 
of periodontal disease. 

9) The effect of toothbrushing, gingival massage, 
and interdental stimulation (oral physiotherapy) 
upon the periodontal tissues. 

10) Theoretical basis underlying the selection of 
various types of prostheses in order to benefit the 
periodontal tissues (fixed and removable prostheses, 
precision attachments, and splinting). 

11) Epidemiology of periodontal disease. 

12) Aging and heredity. 

The riddle of periodontal disease will likely be 
solved in one or several of these areas of biomechani- 
cal research, perhaps with an assist from what Hine’* 
calls a better knowledge of “complex relationships 
between many factors, including mental attitudes 
and psychopathology.” 

3Glickman, Irving, and Ramfjord, Sigurd: ibid., p. 83. 
4Hine, Maynard: ibid., p. 47. 

Clinical and Laborato 

Locating a Submerged Root 

William Weiser, D.D.S., Orange, New Jersey 

I. After the area is anesthetized insert a suture needle in the 
approximate area. Take an x-ray of the area. Make an incision at 
the point that corresponds to the position of the root fragment in 
relationship to the needle. 

Removing Denture Teeth 

Frank P. lvorno, D.D.S., New York 

2. Cut the acrylic from the lingual side of the teeth to expose the 
pins or diatoric notches. Do not perforate the base. Flow utility 
wax into this trench. Warm the area with a low flame and while 
the wax is hot flip the teeth from the base with a sharp instrument. 

Depth-indicator for a Periodontal Pocket 

A. Suzuki, D.D.S., Houston, Texas 

3B. Bend and sharpen the points of a cotton plier as shown in the 
illustration. Place one point in the pocket and the other outside. 
The bottom of the pocket is indicated on the outside of the gingival 
tissue by pinching the pliers. 

READERS Are Urged to Collect $10.00 

For every practical clinical or laboratory suggestion that 
is usable, DENTAL DIcEsT will pay $10 on publication. 
You do not have to write an article. Furnish us with 
rough drawings or sketches, from which we will make 
suitable illustrations; write a brief description of the 



Securing Baseplates to the Model 
A. Holloszy, D.D.S., St. Lovis, Missouri 

he 34, Attach adhesive tape to each side of the upper and lower base- 
at plates in such a manner that half the strip sticks to the baseplate 
In and the other half to the model. 

A Mechanical Stop for an Endodontic Instrument 

Jerome A. Klees, D.D.S., Amenia, New York 

5. The rubber plunger from an anesthetic tube makes a convenient 
le device to place on an endodontic instrument to act as a stop to 
'Y prevent the instrument from passing through the apical foramen. 

Removal of Alginate Impressions 

Richard T. Matousek, D.D.S., Apple Creek, Ohio 

f 6. Fasten the two wire loops to the perforated tray. When the 
alginate has set pass an instrument through the loops to withdraw 
the impression. 

technique involved; and jot down the advantages of the 
technique. This shouldn’t take ten minutes of your time. 
Send your ideas to Clinical and Laboratory Suggestions 

Editor, DentaL Dicest, 708 Church Street, Evanston, 


Vaccination for 

The wider use of vaccine is warranted 
today in the light of an increasing 
number of favorable reports. The 
question now is who should receive 
the vaccine. The choice is conditioned 
by the purpose of vaccination. 

To prevent death, vaccine should 
be given to: (1) those with chronic 
debilitating disease, for example, car- 
diovascular, renal, or pulmonary, (2) 
pregnant women, particularly during 
the last trimester when risk is great- 
est, and (3) the extremely young or 
old, because mortality from influ- 
enza and pneumonia is most common 
at life’s extremes. 

To prevent disease, vaccine is most 
effective in children, because the at- 
tack rate is greatest at 5 to 9 years 
of age. Even above and below these 
years the rate is great. 

To prevent disruption of normal 
community functions, persons con- 
cerned with health services, public 
safety, public utilities, and transpor- 
tation, should receive special consid- 
eration with respect to vaccination. 
Also it is wise to protect the home- 
maker in order to preserve the well- 
being of the family unit. 

Adults should be vaccinated sub- 
cutaneously with at least 400 CCA 
units of virus. Intracutaneous admin- 
istration for adults is not recommend- 
ed because the smaller antigenic mass 
civen induces lower and often inade- 
quate antibody levels. Children aged 
6 to 12 years may be vaccinated 
twice subcutaneously at one or two- 
week intervals with half the dose 
selected for adults. In this age group, 
the divided dose schedule promotes 
higher antibody levels at an accept- 
able reaction rate—about 20 per cent. 
Multiple intramuscular doses are giv- 
en to children 3 months old to pre- 
school age, to provide some protec- 
tion without invoking the uncommon 
sensitivity of this group to toxic ef- 
fects of influenza virus vaccines. Re- 
action in children can be largely sup- 
pressed by administration of aspirin 
during the first twenty-four hours 
after inoculation. Such treatment is 
seldom necessary for adults. 


and the 



Recent evidence indicates that high 
antibody levels can be induced to 
virus strains not previously encoun- 
tered. Primary vaccination, although 
sensitizing anti-body-forming mech- 
anisms of the body, may induce only 
extremely low levels of antibody to 
new strains. A second vaccination 
given six or more months later pro- 
duces high levels of antibody to old 
as well as new strains. Annual vac- 
cination has additional merit be- 
cause high levels of broadly reacting 
antibodies can be induced with poly- 
valent vaccines of broadest coverage. 

Davenport, F. M.: Recent Advances 

in Prevention of Influenza by Vac- 
cination, Mod. Med. 26:115-122 

Lung Carcinoma 

Bronchogenic carcinoma appears 
to be increasing in incidence today. 
Unfortunately, in the early stages it 
is often undetectable. In many in- 
stances metastasis has already oc- 
curred at the time the patient is first 
seen. At the present time the only 
means of detection are periodic ro- 
entgenograms and a constant vigil 
for the early symptoms and signs 
of bronchial obstruction. 

The important early symptoms are 
persistent cough, local rhonchus that 

the patient hears or feels when ey. 
ercising or when lying on the af. 
fected side, clubbing of the fingers 
and hemoptysis. Pneumonia that re. 
curs in the same area, resolves sloy. 
ly or starts without preceding bron. 
chitis also suggests bronchia! ob. 
struction. Early signs are related to 
narrowing of a bronchus and con. 
sists of local rhonchus that is brought 
out by having the patient lie on the 
affected side, obstructive pneumon. 
itis, atebectasis or a localized area of 
obstructive emphysema. 

Any patient in whom carcinoma js 
diagnosed bronchoscopially or js 
strongly suspected should be explored 
promptly, provided no contraindica. 
tion is apparent and the functional 
status of the lungs will permit the 
necessary surgery. 

The rate of growth of a broncho- 
genic carcinoma may vary greatly, 
For this reason, size of a tumor js 
not a reliable index of prognosis, 
An extremely small anaplastic lesion 
may be associated with widespread 
metastasis. On the other hand, a 
nodule may have slowly attained 
considerable size without producing 
distant metastasis. 

Lesions that increase slowly in 
size have the most favorable progno- 
sis. Many such lesions have been 
resected after they have been known 
to exist for four or five years, and 
five-year cures have been attained. 
It is important to realize, however, 
that the observation of only a little 
change in the size of a_ nodular 
lesion over a period of several years 
does not warrant the assumption of 

Pneumonectomy and mediastinal 
dissection are not required when dis- 
tant metastasis can be demonstrated. 
The finding of carcinoma in the 
scalene fat pad biopsy is a sign of 
distant metastasis. 

Thoracic surgery has come of age 
and relatively few parts of this coun- 
try lack good facilities close at hand. 
Accuracy of radiologic diagnosis has 
kept pace with the surgical tech: 

Stead, William W.: Indication for 
Thoracic Surgery, Gen. Practitione! 
26:70-73 (June 1) 1958. 


to d 





School Children— 
Tuberculin Tests 

As a periodic procedure, the tu- 
berculin test is highly recommended 
for all children after the age of 
two months and for as long as no 
reaction is elicited. It is important 
to detect tuberculosis, if it occurs, as 
early as possible. The test is the 
earliest method by which tubercu- 
losis can be diagnosed. 

The tuberculin test will detect the 
disease while the lesions are usually 
too small to be detected by physical 
examination, including inspection of 
the chest by x-ray film. Such small 
lesions are potential sources of gross 
clinical disease. 

A child who becomes a reactor to 
tuberculin has usually been in close 
contact with an adult, such as a par- 
ent, grandparent, or other relative 
who has contagious disease. Seeking 
the source of the infection among 
adult associates is a most valuable 
clinical case-finding method. The ear- 
lier the infection in the child is found, 
the better are the results for the 
child. Also, the earlier the disease in 
the child is detected, the fewer other 
persons will be infected and the better 
the patient’s chances of recovery will 

The importance of finding the dis- 
ease soon after the infection has oc- 
curred is increased in light of the 
appearance of antituberculosis drugs. 
A great many recent tuberculin con- 
verters are now being treated with 
these drugs. Those currently available 
are not germicidal, but they suppress 
tubercle bacilli. They do not cure. 
However, it appears that they occa- 
sionally prevent the development of 
acute forms, such as miliary disease 
or meningitis. 

When the infection is found early 
the lesions are microscopic and vas- 
cular. At this point the drugs may be 
expected to enter so as to come in 
contact with all tubercle bacilli. As 
time passes, however, tuberculosis 
lesions often lose their blood supply, 
after which a drug could not be ex- 
pected to reach the organism in avas- 
cular necrotic tissue. 

In most parts of the United States, 


the number of children who develop 
tuberculosis so as to become reactors 
to tuberculin is quite small, often not 
more than 2 or 3 per cent during the 
grade-school period. There is a high 
incidence of tuberculosis among per- 
sons 40 years of age or older, as 
manifested by the tuberculin reaction. 
Some of these older persons become 
contagious unknowingly and dissem- 
inate tubercle bacilli. Children every- 
where should be tested periodically to 
make certain that those who may be 
infected from unsuspected sources 
are detected promptly. 

Questions and Answers: Examina- 
tion for School Children, JAMA 167: 
1802 (August 2) 1958. | 

Psychiatric Diseases 
of Aging 

When psychiatric disease is present 
in old persons, the changes may be 
sudden or extremely subtle. From the 
slight mental alterations in the aging 
patient there is a sliding scale of in- 
creasing impoverishment of mental 
resources. Usually the old person dis- 
likes more and more to change. He 
has progressive reduction in his am- 
bition and activity. He becomes con- 
stricted and self centered, has in- 
creased difficulty in comprehension 
and requires more time and effort to 
perform usual duties. New ideas can- 
not be handled. The deterioration 
may be hastened by a physical illness, 
an accident, or severe emotional 
shock or disturbance. The subject 
becomes indifferent to the ceremonies 
and courtesies of social life. He re- 
sents interference by young people 
and complains that he is neglected. 
He shows a hostile, but anxious or 
fearful dependence. 

Sentiments may be increased and 
charitable impulses disappear. Often 
sexual activity may be exaggerated, 
especially in men with indecencies, 
generally with children. The old per- 
son becomes indifferent in habits of 
dress and toilet. He tends to be dis- 
trustful, prying, and suspicious. He 
begins to reminisce more as memory 
for recent life sinks away. Often he 
lives in his childhood as he recalls 
early incidents. He may speak of par- 

ents and grandparents as persons who 
are still living. 

The orientation becomes defective 
and confusion severe. Such a person 
may wander away and get lost. He 
may go into the kitchen, turn on the 
gas, and leave without lighting the 
jet, only to come back later, light a 
match and cause an explosion. He 
may become exceedingly reckless at 
night, wandering about the house in 
an aimless, distracted way. The aged 
may hoard articles of no value, carry 
quantities of worthless objects in 
pockets, and secrete in forgotten hid- 
ing places items that others may need. 
Hallucinations and delusions are 
common. Physical incapacitation 
progressively increases and _ finally 
most patients are bedridden. This is 
senile dementia. Rarely is the onset 
of this disease noted before 60 years 
of age. 

The reaction of the person to the 
process of aging depends to a large 
extent on his previous personality. 
The well-adjusted, mature, adequate 
man can handle the sunset of his life 
well. He can give ‘of himself, of his 
substance, can share the pleasures of 
those about him. The person who ar- 
rives at this period bolstered only by 
his defenses sees one after another 
crumble. He erects new ones, each 
more rigid, more constricting and 
more arbitrary. The legal implica- 
tions are many because promises are 
broken and wills rewritten. 

Boshes, Benjamin: Neurologic and 
Psychiatric Aspects of Aging, Mod. 
Med. 26:71-79 (May 1) 1958. 


Alcohol can be absorbed through 
all the mucous surfaces of the body. 
When alcohol is ingested, the alcohol 
is absorbed in the upper portion of 
the gastrointestinal tract. The com- 
paratively small molecular size per- 
mits it to pass readily through mem- 
branes by simple diffusion. To a large 
extent, its absorption follows the 
principles of diffusion. The greater 
the difference in alcohol concentra- 
tion in the fluids on two sides of a 



Problems of sprueing 

A laboratory customer turned over some 
sprues to one of our Ney Technical 
Representatives for examination by our 
Research Department. The following is 
a report made after analysis of the prob- 
lems involved. 

“We have examined the sprues sent to 
us and in many cases the casting had 
apparently separated from the sprue 
while still in the investment. This situa- 
tion, as illustrated below, occurs when 
too small a sprue is used to make the 
casting. The small sprue has separated 
from the casting, leaving shrink spot 
porosity both in the casting and in the 


“On the other hand, a similar casting 
made, using a larger sprue, does not 
separate in the investment as illustrated 
in the following photograph. 

“If an air pressure casting machine is 
used, a small sprue and a reservoir must 
be used. The proper sprueing for air 
pressure casting is shown here. 

“When too small a sprue is used to make 
a casting, the sprue will solidify before 
the casting, causing shrinkage porosity 
to occur in the casting. In extreme cases 
it may cause the separation of the sprue 
from the casting. This separation can be 
corrected by the use of a larger sprue 
(8 ga. is usually satisfactory) attached 
to the heaviest portion of the casting. A 
thick area of casting should not be 
separated from the sprue by a thin sec- 
tion, but another sprue should be added 
to the second thick area. One illustra- 
tion of this condition would be in an 
MOD casting in which the thin occlusal 
separates a heavy mesial from a heavy 
distal. In this case, it is desirable to 
sprue to both the mesial and distal of 
the casting. The same principles apply 
to sprueing a large casting, and in most 
instances, each unit of a splint should 
be considered as an individual sprueing 


membrane, the more rapid is the 
diffusion rate from the side of higher 
concentration to the lower side. 
The absorption of alcohol from the 
gastrointestinal tract is of major in- 
terest because of its relation to al- 
coholic liquors. However, alcohol ab- 
sorption may result from the injec- 
tion of its solution into the body, use 
of an alcohol-containing enema or 
douche, or inhalation of its vapor. 
When alcoholic liquor is swallowed, 
it is absorbed into the capillary cir- 


culation. Arterial blood is slightly 
higher in alcoholic concentration than 
is venous blood, especially during the 
period of active absorption. Absorp- 
tion takes place at a rapid rate, de- 
pending, among other things, on the 
quantity of alcohol ingested, its con- 
centration in the drink, the nature 
and quantity of the diluting material 
already in the stomach and the dura- 
tion of its sojourn in the stomach. 
When taken on an empty stomach, 
the alcohol from a single drink of 

liquor has been about 90 per cent 
absorbed by the end of the first hour, 
It appears that absorption from the 
upper portion of the small intestine 
is even more rapid than the penetra. 
tion through the stomach wall. Liquor 
consumed after a meal has less ip. 
toxicating effect than the same amount 
of liquor taken on an empty stoinach, 
This slowing is due, not simply to 
dilution by the large volume of stom. 
ach contents, or the slowing of their 
passage into the rapidly absorbing 
small intestine, but also to the coating 
of the stomach by less permeable food 
components. It is known that certain 
fatty foods, such as milk, cream or 
olive oil could inhibit alcohol absorp. 
tion, but many nonfat food stuffs do 
just about as well. A good-sized help. 
ing of mashed potatoes is one of the 
best deterrents of alcohol absorption, 
Habituation to the use of alcoholic 
liquors does not materially alter the 
rate of alcohol absorption. At high 
altitudes alcohol is absorbed mor 
readily and produces higher blood 
alcohol concentrations than at sea 
levels. With nearly all persons, al- 
cohol is rapidly eliminated from thef 
body, chiefly by oxidation to carbon 
dioxide and water. 

Muehlberger, Clarence W.: The 
Physiological Action of Alcohol, 
JAMA 167:1842-1845 (August 9) 
1958. | 

The Castle That Was Destroyed is 
a colorful folder about dental health. 
Kids love it. And before they know 
it, they learn easy-to-remember 
dental truths. And some of them 
carry the word to other kids, and 
to parents, too. Price, 100 for $15. 

1005 Liberty Ave., Pittsburgh 22, Pa. 



a, = @ee OCOD 

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bing i 

a oF 
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- the 
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nore Fe 





Profile of the 
Stress-Blind Man 
DesPITE the exhortations from biolo- 
gists who know the most about the 
affairs of the human organism, many 
of us insist on destroying ourselves. It 
is not overt suicide, but a kind of de- 
fiance that psychologists may call a 
fulfillment of the death wish. Many 
of us continue to overdraw our ac- 
count in the biologic bank and end in 
the final bankruptcy of death too soon. 
We are blind to our own potentials 
and blind to our tolerances—stress- 
blind. We know less and seem to. care 
less about ourselves than about the 
things around us. Our lives seem to be 
of less concern than our automobiles. 
We resist information that may help 
us; we accept the trivia of conversa- 
tion and of entertainment that does us 
little long-term good. When serious 
conversation on fundamental subjects 
is introduced many of us flee posthaste 
to lighter subjects. We are appalled 
with the prospect of being labelled 
“intellectual” or “serious.” Is it that 
we fear to listen to important and 
sometimes disturbing subjects and 
prefer the safety of small talk? Do we 
choose the blinders of “I won’t look” 
for some reason of inner security ? 
Do you recognize any part of your- 
self in this portrait drawn by Henry 
I. Russek, M.D. in the Journal of the 
American Medical Association?” 
“In almost every instance we found 
the young coronary patient to be a 
victim of overwork, often as a result 
of an unrelenting drive, an intense de- 
sire for recognition, or a profound 
sense of obligation to his employer, 
his family, or others, but more com- 
monly simply as a consequence of 
meeting life’s challenges with maxi- 
mum and unstinting effort. It was ap- 
parent that these patients had been 

'ANUARY 1960 

compulsive about time, overmeticu- 
lous, and ‘blind’ to their own stress 
end-point. They were often concerned 
about trivia, impatient with subordi- 
nates, and worrisome. As perfection- 
ists they frequently chose to do the 
work themselves rather than to dele- 
gate it to others. Being ‘stress-blind’ 
they took on more responsibilities at 
an occupational, social, or domestic 
level than good judgment appeared to 
dictate, minimized their symptoms, 
and neglected prudent rules of health. 
Perhaps the most characteristic trait 
of the young coronary patient, how- 
ever, was his restlessness during lei- 
sure hours and his sense of guilt dur- 
ing periods of ‘relaxation.’ As a con- 
sequence, he rarely took vacations, 
and such leisure time as he did pos- 
sess was frequently regimented by 
obligatory participation in an assort- 
ment of social, public, or educational 

We should all be familiar with the 
monumental research on stress that 
has been done by Hans Selye. Do we 

believe, as he believes, that: “Adapta- 
tion energy seems to be something of 
which everybody has a given amount 
at birth, an inherited capital to which 
we cannot add, but which we can use, 
more or less thriftily, in fighting the 
stress of life? 

“When a human being is born—un- 
less he wants to kill himself—he can- 
not stop, either, before he has com- 
pleted his mission on earth. Yet he 
too can do much, through voluntary 
choice of conduct, to get as far as pos- 
sible with a given bodily structure and 
supply of adaptation energy, under 
given social conditions. For instance, 
he can live and express his personality 
at a tempo and in a manner best suited 
to his inherited talents, under the pre- 
vailing social conditions. The two 
great limiting factors—which are set 
once a man is born—are: his supply 
of adaptation energy and the wear and 
tear that the weakest vital part of his 
body can tolerate. 

“So, actually, we can accomplish a 
creat deal by living wisely in accord- 


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ance with natural laws. We can deter- 
mine our optimum speed of living, by 
trying various speeds and finding out 
which one is most agreeable.” 

Do we accept the philosophy of the 
prudent life so ably expressed almost 
a quarter-century ago by the respected 
cardiologist, Sir Thomas Lewis?- 

“ “Very prudent people live quietly 
and moderately; they have their 
simple daily routine of work and 
pastime, enlivened by occasional ex- 
cursions and entertainments, social 
gatherings and visits to and from their 
friends. They are temperate in their 
eating, taking no more than will main- 
tain them in robust health, arranging 
their diet to consist chiefly of plain 
good food, relieved occasionally of its 
monotony by a more elaborate, but 
not heavy meal. They are regular in 
their habits of work and exercise, and 
in their mealtimes. They are strictly 
temperate in their drinking. They con- 
trol their emotions and their passions. 
They avoid all forms of excess. They 
use tobacco little if at all. They wel- 
come the freshness of abundant air 
and open spaces, delighting in the 
feeling of invigoration that accom- 
panies active exercise; they love the 
warmth of sunlight playing on their 
skins and the sleepiness of healthy 
fatigue. These are habits that few 
people in industrial countries now 
adopt, that fewer still maintain. The 
cares and distractions of an increas- 
ingly complex life, indoor or seden- 
tary occupation, advancing years and 
decreasing energy interfere less or 
more, and the prudent rules are 
neglected; neglect is the easier be- 
cause the penalties, owing to the 
body’s great power of resistance to 
disease, are uncertain in their inci- 
dence and often long deferred.’ ” 

Above are the words of three emi- 
nent physicians. At this beginning of 
the New Year and at the time of good 
resolutions are we prepared to see any 
part of ourselves in these projections 
of the stress-blind man? 

Learning Made Easier 

The dentist or oral surgeon may 
now sit comfortably in his home or 
office and view a series of 1400 pairs 
of colored stereoscopic pictures on 
surgical procedures. These pictures 

are mounted on reels of 7 pairs each 
and are studied through an electrically 
illuminated three dimensional View. 
Master® focusing stereoscope. With 
each slide is a description of the sur. 
gical procedure published in book 

This material has been developed 
by Wilton W. Cogswell, D.D.S., visit- 
ing professor of oral surgery, Univer- 
sity of Kansas City, School of Dentist- 
ry. The stereoscopic pictures are used 
as teaching aids at that school and are 
available to the profession through the 
medical publishers, Williams and Wil- 
kins of Baltimore, and J. W. Stacey, 
Palo Alto, California. 


Although this is not the time of 
year for “reunions” there are always 
dental meetings to attend and these 
are reunions of sorts. 

Whenever men (and more particu- 
larly women) come together the covert 
looks of appraisal are made. The other 
fellow looks a little older, balder, and 
fatter than you think you do yourself. 
The other fellow is thinking the same 
thing about you. The other paunch is 
more noticeable than your own! 

Men, prompt to deny these allega- 
tions, are sensitive about “looking 
old.” The toupee trade and the elastic 
abdominal supports are rather futile 
attempts to turn time backward in 
flight. Men are probably less often 
customers of the plastic surgeon than 
are women: to pick up the slack in a 
sagging chin line, to uplift the pendu- 
lous, or to trim a bit from the hams. 
Even the most respectable of the jour- 
nals in surgery often give tips on such 
techniques to the surgeon who wishes 
to explore the territories of anti-geri- 

When old friends meet in reunion 
lightning appraisals are made in the 
physical, economic, and social fields. 
Status is determined by how one looks 
—tired or drawn; too fat for comfort, 
too thin for prosperity; too stooped 
from work, too straight from sports. 
What joints are stiff, what face is 
slack? What voice is strong, what 
wrinkle deep? 

Economic status is shown by the car 
one drives, by the spots upon the 

(Concluded on page 48) 


The first tooth is a family triumph! 

. . Every succeeding tooth, to the 
total of 52, should be of major interest 
to parents ... Show parents on a 
dynamic time-wheel what teeth should 
appear where and at what time. 
The TootH Eruption CALCULATOR 
shows the dental development from 
birth to adulthood — when all the 
teeth are due for appearance in the 

Although there are 44 separate 
views of the child’s mouth on this 
chart, parents will not find it confus- 
ing, for only the two (or four—in 

Dental Digest 

1005 Liberty Ave., 
Pittsburgh 22, Pa. 
Please send me........ CALCULATORS 
I enclose $........ 


Actual size 7%" 

What Every Parent Should Know-=- 
about his child’s teeth 

the case of mixed dentition) which 
apply to a certain age level are visible 
at one time. The dials (one on each 
side of the two-sided chart) rotate 
to show upper and lower teeth 
through 14 stages of development. 

Every dentist and physician will 
want the TootH Eruption CAt- 
CULATOR in his office to demonstrate 
tooth development to the parents of 

Every dentist and physician will al- 
so want the TootH Eruption CAt- 
CULATOR to give to parents for home- 
use and patient education. 

Pe, ab 5S a tae beh aeies 

ae ay eee er ee State ... 


COLOR, $1.00 each, 6 for $5.00 

See pages 37, 38, 39 D.D.1 

Wyern, P.O. Box 8299, PHILADELPHIA 1, PA. 

Please send booklet, Drugs of Choice in 
Dental Practice. 

See page 41 D.D.1 
43rp & CoLiins, M1Ami BEACH, FLORIDA 

Please send brochure and rates. 


Address I iciscitesiscindineicelete 

City testa 

See page 40 D.D.1 one 


413 Peart St., ALBANY 1, N.Y. 

? Send me FREE of charge more informa- 
tion on the Vertiscriber Technique. 


Address _ 

JANI ARY 1960 

509 Fifth Ave., New York 17, N.Y. 

Please send information on your products. 


See page 43 D.D.1 
Eur Litty & Company 

Please send information on Darvo-Tran. 

See pages 44, 45 

Tuos. Leemine & Co., INc. 
155 East 441TH St., New York 17, N.Y. 

Please send me descriptive and reprint 
material on Thermodent Tooth Paste. 

Address _................ 

See page 48 

Younc DENTAL Mec. Co. 
4958-D SuspurBAN TRACKS 
St. Louis 8, Mo. 

Please send information on Enodon Rack. 



See page 48 D.D.1 

447u Sr. & Cotiins, M1Ami BEAcH, FLORIDA 

Please send descriptive booklet. 


See third cover D.D.1 

Tue L. D. CAautk Co. 
Mitrorp, DEL. 

Please send information on Characterized 

Address - 



See fourth cover 
Tue Dentists’ Suppty Co. or N.Y., 
York, PA. 

Please send Trubyte Slide Library Cata- 

Eee eee ee 

Address _____... meen! 




Matching numbered holes speed finding and 
replacing files and reamers. Companion dish 
continuously protects and sterilizes. Visual 
inventory gives split second check of com- 
pleteness of set, prevents misplacements. 
Work on two successive patients possible 
without reloading. Rack $12.50. Sterilizing 
Dish $2.50. Set $15.00. 

. eliminates measurements and errors 
in gaging distance between crown and 

Order from your Dealer. 

4958-D Suburban Tracks 

St. Louis 8, Mo. 

necktie, by ornaments that flash and 
glitter on the body of man and wife. 

Social prestige is acclaimed by the 
clubs one boasts, the trips one takes, 
by the address upon a street, by the 
schools that children attend. 

Reunions are often times of ribald 
jest and bonhomie that has a hollow 
ring. Nostalgic talk that hangs heavy 
in the air falls flat because the years 
between have broken the chain of 
meaning. Wives sit by with boredom 
patiently concealed or frankly ex- 
pressed. The yawn may be hidden 
with grace behind a manicured hand 
or openly made to show teeth that 
have received scant care from’ the 
dentist-spouse who tries,,so-hard to 
acclaim his status before his friends 
of other days. 

Nicknames that on another day 
might have expressed some of the 
exuberance of youth sound absurd 
when bestowed upon a friend who has 
passed the mid-point of his life. 

The sensitive soul feels the tones of 
sadness in reunion because he may 
realize that none has lived up to his 


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ambitions and expectations. He re. 
calls the boasts of youth and now ip 
later regret knows that they wiil never 

Human relationships need constant 
culture. A meeting among friends once 
a year or every ten years is not enough, 
The reality stands stark that years 
have dimmed interest and rapports; 
that each one has adopted a different 
set of interests and values. Men accept 
this fact with less grace than do 
women. Reunions may be sad affairs 
for men because they are sentimental. 
ists and enjoy the flow of reminis. 
cence. Women are the ones who see 
children grow and pass from stage to 
stage. They are always mystified be. 
cause they see their men grow so little! 

E. J.R. 

Advertising. Index 

AGSA 42 
Anacin 7 Fe 
Astra Pharmaceutical Products, 

Inc. Insert | 
Austenal, Inc. l J 
Caulk Co., The L. D.__. Third Cover 
Darvo-Tran 43 
Dentists’ Supply Co. of N.Y., 

The Fourth Cover 
Equanil 37 
Laclede 8 
Lederle Laboratories 3 
Leeming & Co., Inc., Thomas___.44, 45 
Lilly & Co., Eli 43 
Mepergan 9 
Myerson Tooth Corp. - 6 
Ney Co., The J. M. 36 
Pen-Vee K 39 
Peter, Strong & Co., Inc. “” 

San Marino Hotel Al 
Sorrento Hotel 48 
Standard Laboratories, Inc. ___--..- 4 
Thermodent 4A, 45 
Ticonium AO 

Universal Dental Co...Second Cover 
White Dental Mfg. Co., 

The S. S. ila 
Whitehall Laboratories = © © 
Wyeth Laboratories. 5, 37, 38, 39 
Young Dental Mfg. Co. 48 
Zactirin ee