British Journal of Orthodontics

ISSN: 0301-228X (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/yjor19

A Review of Anterior Open Bite

E. Mizrahi B.D.S., D.Orth., F.D.S., R.C.S., M.Sc.

To cite this article: E. Mizrahi B.D.S., D.Orth., F.D.S., R.C.S., M.Sc. (1978) A Review of Anterior
Open Bite, British Journal of Orthodontics, 5:1, 21-27, DOI: 10.1179/bjo.5.1.21

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British Journal ofOrthodontics/Vol 5/1978/21-27 Printed in Great Britain~

A Review of Anterior Open Bite

E. Mizrahi, B.D.S., D.Orth., F.D.S., R.C.S., M.Sc.
604 Medical Arts Building, Jeppe Street, Johannesburg, South Africa

Abstract. Anterior open bite malocclusion is reviewed under the headings of aetiology, morphology and
treatment. The aetiology is discussed within the classification originally described by Dockrell in 1952. The
morphological differences between skeletal and dental open bite together with the extra oral, intra oral, and
cephalometric characteristics are described. Recognition is ginn to the recent developments in maxillo facial
surgery and the importance of a combined surgical and orthodontic approach to the treatment of skeletal open
bite. The merits of the palatal crib either on a fixed or removable appliance to break a thumb sucking habit
are discussed in relation to the dental open bite. The relationship of post treatment stability to the adequate
removal or modification of the aetiological factors is stressed.

Introduction Heredity
Anterior open bite may be defined as: That con- In the same way that horizontal skeletal dysplasias
dition where the upper incisor crowns fail to are inherited, so dysplasias in the vertical plane
overlap the incisal third of the lower incisor crowns may also be inherited. These vertical dysplasias can
when the mandible is brought into full occlusion. be associated with either a Class I, Class ll or
Within the limits of this definition, the degree or Class Ill skeletal relationship (Sassouni, 1969).
severity of malocclusion may vary from a mild edge
to edge relationship of the incisor teeth to a severe Non-hereditary Factors
and handicapping malocclusion. The important non-hereditary factors associated
The tendency for anterior teeth to return toward with the aetiology of anterior open bite are:
their original pre-treatment vertical relationship
following orthodontic treatment is well recognized (I) Thumb, finger or foreign body sucking.
and is undoubtedly one of the factors responsible (2) Abnormal tongue function.
for the continuing interest shown by orthodontists (3) Trauma or pathology to the condyle.
in this field. (4) Neurologic disturbances.
In this paper a brief review of the aetiology. (5) Iatrogenic factors.
diagnosis and treatment of anterior open bite will Thumb or finger sucking in a child up to the age
be presented. of four or five years is considered to be a normal
experience resulting in no permanent form of
Aetiology malocclusion. However, persistent thumbsucking
In 1952 Dockrell presented a classification for the extending into the mixed and permanent dentition
aetiology of malocclusion. In its simplest form. he age groups may well result in anterior open bite.
described an equation which stated that: A cause (Popovich & Thompson, 1973, Klein, 1971,
acts at a certain time. on a certain tissue. to produce Fletcher. 1975.)
a result. The cause and effect relationship of abnormal
Anterior open bite like any other malocclusion is tongue function and anterior open bite is not clear.
the result of certain causes either of hereditary or Andersen (1963) considered that tongue thrusting
non-hereditary origin that act pre- or post-natally was not a result of bottle feeding or tonsillitis, but
on the tissues of the orofacial region. was related rather to thumb sucking. Moyers (1963)
Few malocclusions have a single specific cause. as well as Subtelny and Sakuda (1964) considered
more often they are the result of a combination of that enlarged tonsils and adenoids did contribute to
many factors operating within the inherent pre- tongue thrusting. NetT and Kydd ( 1966) felt that
determined growth potential of each individual the pressure of the tongue between the teeth alone
patient. was not enough to induce an open bite, whereas

21
 E. Mizrahi

Proffit and Mason (1975) considered that the tongue thrusting and anterior open bite, decreases
resting posture of the tongue was more important in with an increase in age.
open bite aetiology than the actual swallowing
activity. Tissues
The evidence to date suggests that anterior
The tissues that go to make up the orofacial region
tongue thrust is more likely to enhance rather than
can be divided into four groups. '
cause open bite (Speidel et al., 1972).
True macroglossia is rare, in certain cases tongue (I) Muscular tissue.
size as well as function may be an important factor (2) Teeth.
in the aetiology of anterior open bite (Graber, 1972). (3) Bone and cartilage.
Central nervous system disorders following (4) Soft tissues other than muscles.
injury, disease or mal-development of the brain
contribute to impaired neuromuscular control of In an integrated functioning system such as the
the tongue. Gershater in 1972 carried out a survey orofacial region it is unlikely that any one of the
on children in special schools. He established that above. tissue group~ alone ~ill be affected by a
there was a higher incidence of open bite malocclu- causative factor. It 1s more hkely that a particular
sion among mentally retarded and mongoloid tissue will be primarily affected and other asso-
children. ciated tissues secondarily affected. In a true skeletal
Trauma or pathological conditions, involving the open bite, the basal bone is the primary aetiological
growing condyle, may alter the degree or direction site, the teeth and surrounding musculature are
involved in a secondary manner.
of growth of the mandible resulting in anterior
open bite. A fractured neck of condyle, if not
Result
adequately reduced, results in healing of the fracture
with the mandible in an open bite relationship to The development of an anterior open bite malocctu-
the maxilla. sion as a result of the interaction of the above
Schudy in 1964 introduced the term 'hyper and components completes the equation described by
hypodivergent' in relation to facial growth patterns. Dockrell in 1952.
Moving molars either occlusally or distally in a Anterior open bites are classified into two main
patient with a hyperdivergent growth pattern will groups. t~e s~eletal type and th_e dental type. This
result in an anterior open bite of iatrogenic origin. classificatiOn IS based on what 1s considered to be
the original aetiological site, that is the tissue that is
Time primarily affected by the aetiological agent.
The next factor in the orthodontic equation is time. True skeletal and dental anterior open bite
An aetiological factor will act either pre-natally or represent the two extreme conditions of an entire
post-natally. The action of such a factor may be range of open bite malocclusions.
either continuous or intermittent. With regard to
hereditary influence, the genes controlling the Morphology of Skeletal Open Bite
individual growth patterns are determined pre- In describing the morphology of anterior open bite
natally, but the result of the potential growth it is sufficient to describe only the features of th~
pattern may only be manifest in late adolescence two extreme conditions. The remaining malocctu-
(Sassouni and Nanda, 1964). sions will show characteristics of either the skeletal
The degree of open bite produced by a habit is or dental type to a greater or lesser extent.
dependent on both the duration of the habit and on
the age of the patient. A thumbsucking habit given Extra-oral
up by the age of four. will not result in an anterior Profile: The patient presents with either a straight
open bite of the permanent dentition. If the habit convex or concave facial profile. A characterisr'
persists into the mixed dentition period then the feature of skeletal open bite is the increased low;~
chances for this form of malocclusion to develop facial_height. Th~ lips a_t rest are incompetent anct a
are increased. c~nsc10us_ effort 1~ required to hold the lips together
Certain children actively suck their thumb or With obvwus evidence of muscle strain. During
fingers, while others just allow the thumb to rest swallowing an ~ctive co~traction of the orofacial
passively in the mouth. Variation in the intensity and musculature Will be evident. There is a steep
continuity of the habit, will result in malocclusions Frankfort mandibular plane angle and a marked
of varying severity. The incidence of thumbsucking, antegonial notch is present.

22
A Review of Anterior Open Bite

Fig. 1. Skeletal anterior open bite. Note dental contact only in the molar region.

Frontal: When viewing the patient from the front, in anterior open bite cases the maxillary dental
increased length of the face will give the impression height was greater at both the incisor and molar
of a long thin face. The upper lip is short resulting levels; while Nahoum (1971) and Nahoum et al.
in a high lip line and when smiling the patient ( 1972) found no significant difference in the
shows an excess of upper teeth and gum. measurement from maxillary molar cusp tips to
palatal plane or to S-N plane.
Intra-oral
As a result of the active pressure exerted by the lips Mandible
during swallowing there is a tendency to mild There is general agreement on the features of the
crowding and flattening of both arches in the mandible in skeletal open bite patients. A short
incisor region. The inclination of the incisor teeth ramus is present together with an increased gonia)
will vary depending on the antero-postero relation- angle and a marked ante-gonia! notch. The dento-
ship of the mandible to the maxilla. An important alveolar height in the molar region is reduced while
characteristic feature is the form of the anterior in the incisor region it is increased. According to
open bite when the jaws are brought into occlusion. Hapak (1964) the alveolar height of the mandible in
In the severe skeletal open bite cases, the only the lower incisor area increased as the Frankfort
dental contact between the upper and lower arches, mandibular plane angle increased. The body of the
is in the region of the second permanent molars. mandible may be long or short depending on the
From these teeth the open bite extends forwards tendency to Class Ill or Class 11 skeletal pattern.
opening uniformly to reach its maximum vertical
opening in the central incisor region (Fig. I). In occlll'iioo
The tongue lies forward and gives the impression In skeletal anterior open bite subjects, certain
of being rather large. True macroglossia is rare. features become evident when the jaws are brought
During swallowing an anterior tongue thrust is into occlusion. There is an increased total anterior
evident as the tongue moves forward and laterally facial height, measured from nasion to menton.
to fill the open inter-dental area and form a seal This is due to an increase in lower facial height
with the lips. The gingival condition is hypertrophic measured from anterior nasal spine to menton
due to continual mouth breathing. (Richardson, 1969; Hapak, 1964). The ratio of
upper anterior facial height to lower anterior facial
Cephalometric characteristics height (UFH/LFH) serves as one of the diagnostic
The antero-postero relationship of the mandible to criteria. The normal UFH/LFH ratio was given by
the maxilla will vary in individual cases. The Nahoum in 1975 as 0·8, open bite <0·7, and closed
features characteristic of skeletal open bite are bite > 0·9. Posterior facial height measured from
related to the vertical dimension. sella to gonion is reduced (Nahoum et al., 1972;
Schendel et al., 1976).
Maxilla Wylie and Johnson in 1952 stated that up to a
There is some disagreement in the literature regard- point, "the better the face the more the upper face
ing the height of the maxilla. Subtelny and Sakuda contributes to total facial height". They stated that
(1964) and Sassouni and Nanda (1964) claimed that in a 'good face' the upper facial height expressed as

23
 E. Mizrahi

Fig. 2. Dental anterior open bite. Note 'fish mouth' appearance of the incisor region.

a percentage of total facial height was 43.84 per resulting in a V-shaped upper arch. Due to the
cent. As this percentage decreased the face became increased buccal pressure exerted on the motar
'poor'. teeth by the cheeks during sucking, there is a
The relationship of S-N, Frankfort horizontal, narrowing of the arch in the molar region (Moyers
palatal, occlusal and mandibular planes to each 1963). '
other, are diagnostic characteristics of the hypo- or The mandibular incisor teeth are slightly de-
hyper-divergent face described by Schudy in 1964. pressed and lingually inclined.
In the hyperdivergent face these planes all have a In occlusion, the anterior open bite has a charac-
steep relationship to each other, in contrast to the teristic appearance. The opposing molars and Pre-
more parallel relationship of these planes in the molars are in contact, the canines may or may not
hypo-divergent or skeletal closed bite type of face. be in contact, the lateral and central incisors are in
Nahoum in 1975 pointed out that two occlusal frank open bite. The mouth has the appearance of a
planes should be described. A maxillary occlusal 'fish mouth' (Fig. 2). The open bite is limited to the
plane from the intersection of the molar cusps to the incisor region as opposed to the skeletal open bite
incisal edge of the upper incisor and a mandibular which extends to the molar region. On swallowing
occlusal plane from the molar cusps to the incisal there is a characteristic anterior tongue thrust With
edge of the lower incisor. In skeletal open bite both the tongue coming forward into the incisal opening
the palatal plane and the maxillary occlusal plane to form a seal with the lower lip.
are tipped upwards anteriorly while the mandibular
occlusal plane is canted downwards. Cephalometric characteristics
As this malocclusion is a dental condition rather
Morphology of Dental Open Bite than a skeletal problem, there are no special skeletal
Extra-oral features evident.
There are no characteristic extra-oral features
associated with this malocclusion. In the presence Maxilla
of an increased overjet there will be a convex profile In the maxilla there is no increase in height from the
with incompetent lips. cusps tips of the molars to the palatal plane, but
there may be a ~ec~ease in the vertical. height
Intra-oral measured from the mc1sal edge of the upper mcisors
Maxillary arch: The shape of the maxillary arch to the palatal plane. In the presence of an increased
will show characteristic features related to the overjet, the cephalometric analysis will show both
aetiology. If the malocclusion is due to a foreign angular and linear evidence of proclined upper
body (pencil, pipe) being held passively between the incisor teeth.
incisor teeth, then the open bite is localized to the
particular teeth involved; they will fail to erupt to Mandible
the occlusal level of the other teeth in the arch. The The mandible may show featues related to dys-
same clinical appearance is evident in cases having plasias in the antero-posterior direction. However.
ankylosed upper or lower incisor teeth. When the the skeletal features related to the vertical dysplasia
malocclusion is as a result of a thumbsucking habit, of the mandible described above. will be absent.
then the upper incisor teeth may be proclined Retroclined and crowded lower incisors may result

24
A Review of Anterior Open Bite

from a thumbsucking habit. The alveolar height in for the defect by tooth movement. The dental
this region is not increased. occlusion resulting from surgical correction alone
may be less than ideal because of pre-existing tooth
In occ:lusion malpositions. Oral surgeons recognize that ortho-
As a pernicious thumbsucking habit is one of the dontic correction of tooth malposition and dental
commonest causes of this type of malocclusion, arch form before andfor after surgery improves the
cephalometric analysis shows an increased incidence potential for achieving a satisfactory functional
of skeletal Class 11 jaw relationship ( > ANB occlusion. Combined surgical and orthodontic
angle). This is related to the action of the thumb treatment circumvents many of the limitations of
encouraging the forward movement of the maxilla individually applied treatment modes, but it is
while restraining the mandible. If two occlusal dependent for its success on careful conjoint
planes are drawn as suggested by Nahoum (1975) diagnosis and treatment planning. In addition to
the maxillary occlusal plane will be tilted up direct patient examination and the study of tooth
anteriorly in an anti-clockwise direction while the and arch relationship on dental casts, comparative
mandibular occlusal plane will show little change cephalometric analysis is essential. The cephalo-
from the normal. metric prediction techniques are described by
McNeill et al. (1972). With recent developments
Treatment particularly in the field of maxillary surgery, there
In order to achieve a successful and stable result it are at present a number of operative procedures
is essential to establish an acceptable basal bone available to the surgeon for the correction of this
relationship with adequate co-ordination of maxil- dento-facial deformity (Bell, 1971). In this type of
lary and mandibular dental arches and to compen- malocclusion, the age of the patient has an impor-
sate for any anticipated relapse. tant bearing on the treatment planning. With
Whether it is possible to achieve successful results continuing growth there is a progressive backward
and maintain them in all open bite cases, is doubtful. rotation of the mandible and corresponding increase
It is well recognized that anterior open bite maloc- in the severity of the open bite. (Bjork, 1969 and
clu~ion is one of the most difficult orthodontic 1972). Surgery is consequently seldom undertaken
problems with regard to treatment and stability. before the end of the pubertal growth spurt.
Sassouni and Nanda ( 1964) recognized that a Since the development of dento-facial ortho-
'dental malocclusion' has a better prognosis than a paedics over the last few years, it has become
'dento-skeletal malocclusion'. possible with the use of heavy forces to alter the
In view of the close relationship of orthodontic direction of growth of the mandible. By heavy
relapse to the continuing action of the original upward force on the mandible using a chin cap,
aetiological factor, it is essential that a careful Graber (1975) has shown a marked reduction in
examination and appraisal of the case be undertaken anterior open bite.
and an attempt made to identify the aetiologic Where the severity of the case does not warrant
factor, or the aetiologic site. surgical intervention, some improvement may be
There are four modalities of treatment: achieved by means of orthodontic tooth movement.
The use of vertical intra-oral elastics in the incisor
(I) Orthodontic mechanotherapy. region is of limited value, as the upper incisors are
(2) Surgical therapy. already in supra-eruption. If extractions are indi-
(3) Myofunctional therapy. cated due to associated dental crowding, then the
(4) Combination of two or more of the above. extractions should be limited to the distal regions of
Each one of these has its place in the approach to the dental arch. An attempt to acquire space by
treatment. lt is important to determine which form means of distal movement of molars is contra-
of treatment is the most suitable for each individual indicated. Any form of mechanotherapy which
case. would depress the upper molars and encourage the
upwards and forward rotation of the mandible
Skeletal Open Bite should also be considered. In mild cases it is as well
Severe skeletal open bite malocclusions are re- to consider the advisability of any treatment at all.
fractory to correction by orthodontic means
alone (McNeill, 1973). Surgical correction offers Dental Open Bite
the advantage of direct elimination of the The prognosis in this type of case is dependent on
skeletal defect rather than indirect compensation the ability to halt the action of the factor inhibiting

25
 E. Mizrahi

the full eruption of the incisor teeth. In young Conclusion

children it is a common experience that when the
The final prognosis for the treatment of anterior
thumbsucking habit is controlled the anterior open
open bite malocclusion will vary for each individual
bite closes on its own. In the older patient it may be
case. As a general rule the greater the skeletal
necessary to actively close the open bite by means
elements contribute to the aetiology of the maloc-
of mechanotherapy. This is a simple procedure clusion the poorer the prognosis for orthodontic
accomplished by the use of fixed appliances treatment. Each case requires careful and thorough
together with anterior vertical elastics.
examination in order to formulate the correct
The palatal crib either on a removable or fixed diagnosis and treatment plan for the patient.
palatal bar is the most common form of appliance
used for the control of a thumbsucking or tongue
thrusting habit (Graber, 1963; Subtelny and Sakuda, Acknowledgement
1964; Klein, 1971; Parker, 1971). The author would like to express his thanks to the technical
The specific details of the appliance are of little staff of the Dental Research Unit of the University of the
significance. The important feature is that by some Witwatersrand and South African Medical Research Couna1
for their assistance with photography.
mechanical means the thumb is physically prevented
from taking up a comfortable position in the
References
mouth. A prerequisite for the success of this
Andersen, W. S. (1963)
treatment approach is the willingness of the patient The relationship of the tongue thrust syndrome to
to break the habit. For a patient who sincerely maturation and other factors.
wishes to stop sucking and for whom the habit is American Journal of Orthodontics, 49, 264-275.
an 'empty habit', the appliance will act as a re- Bell, W. H. (1971)
Correction of skeletal type of anterior open bite,
minder and will help the child to break the habit. Journal of Oral Surgery, 29, 706--714.
However, when the thumbsucking is a 'meaningful Bjiirk, A. (1969)
habit' and is important to the child, then a more Prediction of mandibular growth rotation,
psychologically orientated treatment approach American Journal of Orthodontics, SS, 585-599.
should be adopted ( Klein, 1971 ). It is not always Bjork, A. and Skieller, V. (1972)
facial development and tooth eruption,
easy to determine whether the habit is a meaningful American Journal of Orthodontics, 62, 339-383.
or empty one. The safe approach in such a case is to Dockrell, R. B. (1952)
construct a palatal crib on a removable appliance. Classifying the aetiology of malocclusion,
Denral Record, 72, 25-31.
If the habit is an empty one and the patient is keen
fletcher, B. T. (1975)
to stop sucking, then the appliance will be worn and Aetiology of fingersucking: Review of literature.
the habit will cease in 2 to 3 months. The child who Journal of Dentistr~·for Chilclren. 42, 293-298.
wants to continue with the habit in spite of all Gershater, M. M. (1972)
efforts to dissuade him, will remove the appliance The proper perspective of open bite,
Angle Ortlrodontist, 42, 263-272.
from his mouth and suck his thumb. Forcing such
Graber, T. M. (1963)
a patient to stop sucking by means of fixed spikes The "three M's': mus~les. malformation and malo~dusion
on a palatal appliance, may result in further A mericarr Journal of Ortlrodomic's. 49, 418-450. '
psychological problems developing. Craber, T. M. (1972)
Orthodonti~ Principles and Practice.
Third edition. Philadelphia: W. B. Saunders Co. Chapter 6
Tongue Thrusting 255. •
Where the presence of an anterior tongue thrust Graber, T. M. and Swain, B. F. (1975)
associated with an anterior dental open bite has Current Orthodontic Concepts and Techniques.
Second edition, Philadelphia: W. B. Saunders C"o. Volume 1
been established then the procedure of choice is to Chapter 5. 365. '
treat the malocclusion on the assumption that the Hapak, F. M. (1964)
tongue thrust will disappear when the open bite Cephalometric appraisal of the open hite case.
has been reduced. Any form of tongue therapy Anf(lt' Orthodonti.>t. 34, fl5 -72.
Kldn, E. T. (1971)
should be postponed until after the treatment has The thumh-sucking ha hit: Meaningful or emrty?
started. Active myotherapy alone can be con- Amrricrm Jourttol of Orthodontic'•. 59. 2HJ 2H9.
sidered, although positive results with this pro- Mc!'oirill, R. W., Proffit, W. R. and Whitt', R. P. 0972)
cedure have not been clinically demonstrated in Cephalometric rrediction for orthodont1~ surgery.
Anglt' Ortlrodonti.1t, 42, 154-11>4.
sufficient numbers to give evidence that such therapy
Mcl'lieill, R. W. (1973)
can effect a correction or prevent a relapse following Surgical orthodontic corrc~.:tion of oren ll1tc m~locdu•inn.
appliance therapy (Proffit and Mason, 1975). Ameriran Journal of Orrhoclonrin, 64, 38--49.

26
A Review of Anterior Open Bite

Moyen, R. E. (1963)
Handbook of Orthodontics- Second Edition. Year Book
Medical Publishers Inc., 35 East Wacker Drive, Chicago.
Chapter Ill. 127. Pitman Medical
Naboum, H. I. (1971)
Vertical proportions and the palatal plane in anterior open-bite,
American Journal of Orthodontics, 59, 273-282.
Nahoum, H. I., Horowitz, S. L. and Benedicto, E. A. (1971)
Varieties of anterior open bite,
American Journal of Orthodontics, 61, 486-492.
Nahoum, H. I. (1975)
Anterior open-bite: A cephalometric analysis and suggested
treatment procedures,
American Jourrurl of Orthodontics, 67, S 13-521.
AN ATLAS OF
Netr, C. W. and Kydd, W. L. (1966)
The open bite: Physiology and occlusion,
Angle Orthodontist, 36, 351-357.
REMOVABLE
Parker, J. H. (1971)
The interception of the open bite in the early growth period,
Angle Orthodontist, 41, 24-44.
ORTHODONTIC
Popovicb, F. and lbompson, G. W. (1973)
Thumb and finger sucking: Its relation to malocclusion,
American Journal of Orthodontics, 63, 148-155.
APPLIANCES
Profllt, W. R. and Mason, R. M. (1975)
Myofunctional therapy for tongue-thrusting: Background and
recommendations, G C DICKSON and
Journal of American Dental AssoC"iation, 90, 403-411.
A E WHEATLY
Rlchardsoa, A. (1969)
Skeletal factors in anterior open·bite and deep ovcrbitc,
American Journal of Orthodontics, 56, 114-127. In any advancing science there are
Sassounl, V. and Nanda, S. (1964) many new methods introduced over
Analysis of dentofacial vertical proportions.
American Journal of Orthodontics. 50, 801-823. the years. The best are adapted and
SaSSOODI, V. (1969)
the rest rejected. Some techniques are
A classification of skeletal facial types, so ideally suited to their purpose that
American Journal of Orthodontics, 55, I 09-123. they remain unchanged. Others are
Schendel, S. A., Elsenfeld, J., Bell, W. H. Epker, B. N. and modified to suit changes in an evolving
Mishelevkh, D. J. (1976) discipline.
The long face syndrome: Vertical maxillary excess,
American Journal of Orthodontics, 70, 398-408.
Schody, F. F. (1964) The use of acid-etch retained compo-
Vertical growth versus antero-posterior growth as related to site resins. which are now standard in
function and treatment. most dental surgeries. has extended
Angle Orthodontist, 34, 75-93. the scope of orthodontic tooth move-
Subtelny, D. J. and Sakuda, M. (1964) ment. enabling rotations and elonga-
Open-bite: Diagnosis and treatment,
American Journal of Orthodontics, 50, 337-358. tions to be carried out without the use
of special equipment.
Speidel, T. M., luacson, R. J. and Worms, F. W. (19n)
Tongue thrust therapy and anterior dental open bite.
American Journal of Orthodontics, 61. 287-295. This is the second edition of an essen-
Wylle, W. J. and Johnsoo, E. L. (1951) tially practical manual which sets out
Rapid evaluation of facial dysplasia in the vertical plane, simply, mainly by visual methods, ap-
Angle Orthodontist, 11, 165-182.
pliances which have been tried and re-
tried. The drawings largely speak for
themselves and by their use, it should
be possible for the dental surgeon to
communicate with his technician, one
copy being in the dentist's surgery and
one on the technician's bench.

160 pages Paper Illustrated

£3.50 approx

27