Developmental Defects Of Orofacial Structures

C
DEVELOPMENTAL DEFECTS OF
OROFACIAL STRUCTURES
Presented by:
Dr. Deeksha Bhanotia
MDS first year
Guided by:
Dr. Mridula Trehan
Professor and Head
DEPARTMENT OF ORTHODONTICS AND DENTOFACIAL ORTHOPAEDICS
SEMINAR PRESENTATION
1

Contents
• Introduction
• Developmental defects of:
1. Neural Crest Cell Origin and Migration
2. Cleft lip and palate
3. Teeth
4. Jaws
5. Tongue
6. TMJ
• Role of an orthodontist
• Case reports
• Conclusion
• References
2

Introduction
• The development of head, face and neck is a complex phenomenon. The development
of the facial structures starts as early as during the second week of intrauterine
period. During this period of intrauterine development, the craniofacial skeleton is
one of the earliest skeletal structures to be formed in the body.
• Disturbances to development during the early period of pregnancy frequently
results in developmental anomalies of the head and neck.
• A thorough knowledge is required about the various regulating mechanisms
governing craniofacial growth to understand the pathogenesis and management of
craniofacial anomalies.
Premkumar S.: Textbook of craniofacial growth ,( 1st edition);251 3

Abnormalities of Neural Crest
Cell Origin and Migration
Holoprosencephaly and Fetal Alcohol Syndrome
• It is characterized by decreased forebrain and increased tendency for the three
ventricles to form a single cavity.
• The main defect is reduced midline components. Facial defects include defects of
medial nasal prominence.
• Derivatives of the medial nasal process including philtrum and portions of maxilla
(premaxilla) are deficient. Contact of olfactory placodes in the midline results in
failure of the medial nasal prominences to develop and leads to arrhinencephaly.
Premkumar S.: Textbook of craniofacial growth ,( 1st edition);255-256 5

• Increasing deficiency leads to progressively smaller eyes which may unite to
form one median eye or remain as two small eyes close to the midline.
• Exposure to high levels of ethanol at early stages of fetal development
produces fetal alcohol syndrome
• (FAS) which now is recognized as one of the holoprosencephalies
• Ethanol has direct effects on neural plate or the mesoderm. This results in
considerable cell death in anterior neural plate. Normal programmed cell
death is necessary for eliminating selected adult cell types. This takes place
by apoptosis, which is required for normal sculpting of the embryo. If
apoptosis becomes excessive, the embryo's ability to process the debris
becomes overwhelmed and leads to abnormal development. The homeobox
gene MSX1 and MSX2 are essential for the normal regulation of apoptosis.
Premkumar S.: Textbook of craniofacial growth ,( 1st edition);255-256 6

Retinoic Acid Syndrome
• This syndrome appeared after the introduction of the acne drug Acutane in 1982.
• Retinoic acid contains 13- cis-retinoic acid.
• The severity of the anomaly depends on the degree of metabolism of the drug. The
level of the metabolite 4-oxo-retinoic acid are 3 to 5 times higher than the original
parent drug concentration and act as teratogen.
• The main target of retinoic acid is the neural crest cells. The neural crest cells are
killed before leaving the neural plate which occurs at a later period.
• It was found that retinoic acid increases the expression of the MSX2 and causes
upregulation of retinoic acid receptor β (RARβ), which in turn causes increased
affinity for retinoic acid and further increased MSX2 expression causes excessive
apoptosis which causes loss in neural crest cells.

The clinical features of retinoic acid syndrome are:
• Microtia.
• Facial bone and calvarial abnormalities.
• Micrognathia.
• Cleft palate.
• Congenital heart disease.
• Aortic arch abnormalities.
• Cerebellar hypoplasia and vermis agenesis.
• Microcephaly.
• Limb abnormalities.

Thalidomide Related
Craniofacial Abnormalities
• Thalidomide was a drug sold in Germany extensively as an over-the-counter
tranquilizer.
• Many of the early exposures produced craniofacial and cardiovascular
malformations similar to retinoic acid.
• Depending on the time of exposure, it produced malformations similar to
retinoic acid syndrome (exposure on 19-23 days) and related syndromes, as
well as Treacher-Collin syndrome (exposure on days 25-26).
• Other manifestations include limb defects, both pre- and post-axial
hypoplasia. Thalidomide poisoning also causes cleft of the palate.

Neural Tube Defects
• It is one of the five most common human malformations.
• The problems are related to neural tube closure, principally neural fold
elevation and contact.
• Neural tube defects are those involving the brain (anencephaly) and the
spinal cord. Anencephalies are usually lethal.
• There are secondary facial abnormalities, of which occasional cleft palate
(CP) is severe.

DiGeorge Syndrome
• This syndrome is related to maternal alcoholism.
• The manifestations are similar to retinoic acid syndrome except for the
short upper lip which is not seen in retinoic acid syndrome.
• A unique feature of this syndrome is the occurrence of pharyngeal gland
problems (thyroid and parathyroid deficiencies).
• The main etiological agent is ethanol which is lethal for migrating neural
crest cells.
• This syndrome is frequently associated with chromosomal deletion 22.

Down’s Syndrome
• It is a chromosomal disorder that occurs mainly due to trisomy 21. It can
also occur due to translocation in which extrachromosomal material is
translocated to chromosome G or D group and rarely due to chromosomal
mosaicism.
• Clinical features of Down’s syndrome are flat face, larger anterior
fontanelle, with open sutures, small slanting eyes with epicanthal folds, open
mouth, frequent prognathism, sexual underdevelopment, cardiac
abnormalities, and hypermobility of the joints. The clinical features, like the
short upper lip in the midline, and a lop-ear are similar to those seen in
DiGeorge syndrome.
• The main defect is in the migration of neuronal cells of cardiac
mesenchyme.

Hemifacial Microsomia
• It occurs in 1:4000 livebirths.
• It is a common otofacial malformation.
• It is frequently associated with conotruncal and vertebral abnormalities.
• There are no clear environmental associations.
• In most or all cases neural involvement is seen.
• It is characterized by a lack of tissue on the affected side of the face,
usually in the area of the mandibular ramus and external ear.

• Poswillo in the 1970s suggested that hemorrhage from stapedial artery and
tissue necrosis might be involved in the development of hemifacial
microsomia.
• Stapedial artery forms the temporary blood supply to the area of
developing ear and mandibular ramus between 33rd and 40th day of
gestation, which is later taken over by maxillary artery.
• The outer part of the stapedial artery atrophies and seals off.
• Poswillo suggested that hemorrhage from the stapedial artery causes facial
defects associated with hemifacial microsomia.

• It was also found that hemifacial microsomia was associated with many
defects resembling those arising from neural crest cell loss.
• Thalidomide produced many malformation with facial patterns similar to
hemifacial microsomia.
• This suggested that variations in the naturally occurring hemifacial
microsomia result from differing expressions of the same basic defect,
early loss of neural crest cells.
• The main etiology is the death of neural crest cells with the longest
migration path.
• Those taking circuitous route to the lateral and lower areas of the face are
most affected, whereas those going to the central face tend to complete
their migratory movement.
• This explains why midline facial defects including clefts are rarely part of
the syndrome.

Fig. 15.8: Hemifacial microsomia. In addition to
the
malformation of the external ear, as seen in this
patient, many regional structures are usually
deficient (patient and diagram). These include
the middle ear ossicles, squamous portion of the
temporal bone, mandible, muscles of
mastication, and the parotid gland. The
malformations are often largely limited to one
side, as in the patient illustrated [Poswillo
(1973)]
18

Treacher-Collins Syndrome
• This was frequently called as first arch syndrome involving structures derived from
first arch.
• It is characterized by bilateral deficiencies in the lateral orbital rim and
zygomatic area in addition to absent or rudimentary mandibular condyles, short
mandibular ramus, severe antegonial notching and retrognathia.
• The shape of the mandible with a markedly down-turned symphysis is a
characteristic feature. Down-turned palpebral fissures, coloboma, missing
eyelashes, aberrant facial hair over the malar area and ear deformities are likely to
be present.
• The main problem is due to the massive cell death in the trigeminal ganglionic
placode, which alters the further development of the placodal cells, ultimately
resulting in secondary defects in neural crest cell derivatives.

Facial Clefting
• The most prevalent congenital defect of dentofacial development is clefting of
the lip and or palate, which occurs in approximately 0.1 percent of births in
United States.
• The incidence of cleft lip in white population is 1:800 to 1000 livebirths, higher in
Asian populations albeit 1:500 to 600 livebirths and lower in blacks about 1:2000
livebirths.
• The incidence of cleft palate is 1:2000 livebirths.
• Clefts are classified as syndromic (those associated with other malformations
such as holoprosencephalies, hemifacial microsomia and Treacher Collin's
syndrome) and non-syndromic (clefts that are not associated with well defined
syndromes).

• Clefts occur due to any disturbance in the fusion of the facial process namely the
medial nasal process, lateral nasal process, maxillary process and the palatine
shelves from the maxillary process.
• Cleft of lip occurs due to the failure of fusion between the median and lateral
nasal process and the maxillary process which occurs during the 6th week of
development.
• Midline cleft of the upper lip occurs due to split within the median nasal process,
but it is rare.

• Since fusion of lateral nasal process is accompanied by fusion of median nasal
process, defects in fusion not only creates primary palate but also part of the
alveolar ridge.
• Cleft lip is usually accompanied by a notch in alveolar ridge when the secondary
palate is not involved. Closure of the secondary palate follows that of the primary
palate around 8th week of intrauterine life.
• Since closure of secondary palate follows the primary palate, interference with lip
closure can also affect palate closure. An isolated cleft palate occurs after the lip
closure has taken place, sometimes producing a notch in it or a bifid uvula.

• The way in which cleft lip and palate develop has been clarified considerably in
recent years as the morphogenetic movements of the involved tissues have been
better understood. Three recent findings worth a brief comment are:
• Primary palate is formed by the fusion of the lateral nasal process with the medial
nasal process. Forward movement of the lateral nasal process during formation of
primary palate keeps it in contact with medial nasal process. Interference with this
movement can lead to clefting of the palate. Maternal smoking has been shown to be
a major factor in the etiology of cleft lip and palate. The mechanism is thought to
be hypoxia induced failure of the movement of the lateral nasal process. It
interferes with oxidative phosphorylation of the cells, thereby reducing the
synthesis of ATP which supplies energy for the morphogenetic movements.

• A genetic predisposition has also been found. Alterations in the genetic code for
TGFα, NADH dehydrogenase were found to be associated with cleft lip and palate.
• Closure of the secondary palate depends on removal of the tongue from between
the palatal shelves. A relatively large tongue in the affected twin of a monozygotic
pair discordant for cleft palate seems to be a frequent finding. It is now clear that
almost all cases of isolated cleft palate are related to problems in tongue removal,
shelf elevation and contact of the shelves at the proper time.
• Syndromic cleft lip: Two of the commonest syndromes associated with cleft lip are
Vander-Woude's syndrome and cleft lip with ectodermal dysplasia.
Premkumar S.: Textbook of craniofacial growth ,( 1st edition);259
25

Figs 15.10A to K: Embryological origins of the
midline facial structures (A, B). In the developing
embryo, the lateral nasal processes form the
alae and sides of the nose, while the medial
nasal processes form the intermaxillary segment,
composed of the upper lip philtrum, the primary
palate and the four incisor teeth. The maxillary
process forms the remainder of the upper lip and
the secondary palate, consisting of the hard
palate and associated dentition anteriorly and
posteriorly, and the soft palate. Various types of
orofacial clefting:
(C) unilateral cleft lip;
(D) bilateral cleft lip;
(E) unilateral cleft lip and primary palate;
(F) bilateral cleft lip and primary palate;
(G) complete unilateral cleft of the lip and palate;
(H) complete bilateral cleft of the lip and palate;
(I) isolated cleft of the secondary palate;
(J) isolated cleft of the soft palate;
(K) submucous cleft of the soft palate
26

Achondroplasia
• This is caused by the failure of primary growth cartilages of the limbs and
cranial base to grow properly. It is transmitted as an autosomal dominant trait.
Forward growth of the mid face is produced by the normal lengthening of the
anterior cranial base, which in turn is dependent on the growth at sphenoccipital,
inter- sphenoidal and spheno-ethmoidal synchondroses. In achondroplasia, growth
is diminished at these synchondroses.
• The resultant features include short arms, legs and characteristic midface
deficiency (most accentuated at the bridge of the nose). The anterior cranial
base is of normal length and the posterior cranial base length is shorter.

Premature Closure of Cranial and
Facial Sutures
• Premature fusion of the midsagittal or posterior cranial sutures can produce
deformities of head without affecting the face, e.g. Scaphocephaly—premature
closure of sagittal suture.
• Unilateral fusion along the coronal suture ring (plagiocephaly) has the potential to
produce facial as well as cranial asymmetry.
• Premature fusion of sutures may cause secondary problems in the cranial base.

• Crouzon’s syndrome results from the premature fusion of the posterior and
superior sutures of the maxilla along the walls of the orbit with cranial base
involvement.
• It is characterized by symmetric maxillary deficiency that affects the infraorbital
area.
• It is also characterized by shallow orbits resulting in protruding eye balls. The
fusion extends to the cranium.
• Three fourths of the patients have fusion of the coronal, sagittal and or
lambdoidal sutures.

• Apert’s syndrome is characterized by fusion of multiple facial and cranial sutures
and early fusion of the synchondroses of the cranial base.
• These patients have an appearance similar to Crouzon’s syndrome and have
syndactyly as an additional clinical feature.
• Another important feature is that the metopic suture and anterior fontanelle are
characteristically open at birth and during infancy in these patients, leading to
pronounced frontal bossing and a high steep forehead.

ABNORMAL GROWTH PATTERNS
• It is appropriate in the present context to review those conditions of abnormal
facial structure which may have been caused, either wholly or in part, by
abnormality of growth mechanisms or growth patterns. It is well recognized that
facial abnormality is a feature of many pathologic conditions and that there are
different causes.
• Enlow et al have classified them into two broad categories with respect to the
time of their recognition and are commonly used:
• (1) Abnormality of early embryonic development
• (2) Abnormality of late fetal or post natal growth.

• In Group 1, the early differentiation of tissues and developmental processes
would be affected.
• Examples would include conditions of hemifacial microsomia, micrognathia, Apert
syndrome, Crouzon syndrome, and cleft lip and palate.
• In each of these conditions some modification of later growth patterns may be
observed as a consequence of the developmental abnormality.
32

• In Group 2, it is presumed that the abnormal process becomes operative after
the embryonic period, that is, after about the third month of fetal life.
• This group would include abnormalities due to trauma, endocrine malfunction,
iatrogenic aspects of cleft lip and palate conditions, and skeletal malocclusions.

• Group 1 abnormalities: It is noteworthy that the majority of craniofacial
abnormalities of clinical interest exist within a normal or potentially normal tissue
environment.
• Hemifacial microsomia frequently manifests as partial agenesis of the mandible in
association with skin and auricular anomalies. Surgical correction of the mandibular
defects frequently fails because the bone grafts are resorbed without replacement
by new bone.
• A new approach to this problem, which appears to facilitate bone development in
the graft matrix, has been deduced from studies of the relationship between
function and morphology.
• The method involves preparation of the surgical site so that the space desired for
the graft is precisely determined and maintained during the healing process.
34

• This maintenance can be obtained through use of an interocclusal appliance.
Congenital micrognathia of the mandible, especially when associated with cleft
palate, suggests a hypoplasia of the mandibular arch (Meckel's) cartilage in the
embryo.
• Mandibular growth may subsequently compensate for a large part of the earlier
retrognathia.
• Therefore, research for methods to accelerate elongation of the andible to the
point of relieving the airway in the critical weeks after birth, merits consideration.

• The Apert and Crouzon syndromes are characterized by failure of midfacial growth
with a tower-shaped cranial vault and frontal protrusion.
• These abnormalities are attributed to premature synostoses of various sutures of
the cranial base, vault, and maxillae.
• There may be a subsequent complication of elevated intracranial pressure in Apert
syndrome.
• The syndactyly in the case of Apert syndrome suggests a mesenchymal response
failure during the 33- to 39-day period of ovulation age.
• Since the entire nasal region is greatly reduced, an abnormality of the cranial base
and nasal capsule in the embryonic chondrocranium may be involved.

• Exploration of the retromaxillary region during surgical treatment of Apert
syndrome has indicated a sphenomaxillary synostosis.
• Very little is known of the pathogenesis of this craniofacial condition, and no
histologic study of the involved structures has been carried out.
• Knowledge relating to time of onset and time of suture synostosis obtained during
surgical intervention, is needed.
• Anatomic research could shed light on whether maxillary hypoplasia is due to
synostoses of the sutures or, perhaps, due to failure of normal differentiation in
the anterior chondrocranial structures.

• Synostoses of cranial sutures are known to relate to static growth relationships.
• It is possible that orthopedic treatment of these patients might be beneficial,
provided the synostosis has not already occurred.
• Early surgical reshaping of the cranial vault by cranioplastic techniques still leaves
the problem of the depressed middle third of the face.

• Cleft lip and palate conditions give rise to secondary deformities of the middle
third of the face during the embryonic and early fetal period.
• These are well established by the twelfth fetal week and progress only slowly
thereafter.
• At birth they appear to be relatively stable entities in which basic growth
mechanisms may be substantially normal.
• The problem, then, in the absence of severe tissue deficiency, is the presence of a
deformity: structural displacement, malformation, and underdevelopment of the
maxillae.

• Group 2 abnormalities: A high percentage of those patients requiring orthodontic
treatment show an imbalance in the relative size of the upper and lower jaws.
• In some cases, this pattern can be established before birth in relation to the
cartilaginous components of the face, namely, the nasal capsule, the cranial base,
and the mandibular arch cartilage.
• In other cases, the deviant pattern arises later, largely the product of postnatal
growth processes.

Pierre Robin sequence (PRS)
• Pierre Robin, a French Stomatologist at French School of Stomatology, defined a
new syndrome in 1923 which involves mandibular micrognathia, glossoptosis and
respiratory distress.
• In 1934, Robin revised the characteristics of the syndrome and included cleft
palate as an additional factor that could be present.
• Formerly, it was named Pierre Robin syndrome, anomalad, or complex.
• Today, it is referred as Pierre Robin sequence because the underdeveloped lower
jaw initiates a sequence of events (i.e., the micrognathia resulting in glossoptosis,
which prevents the palatal shelves to fuse at intra-uterin growth).
Kılıç SC, Kılıç N, Oktay H, Kiki A. Pierre Robin sequence from orthodontic and surgical perspective. World Journal of
Stomatology. 2014 Nov 20;3(4):30-7. 41

• Pierre Robin sequence (PRS) is a triad of micrognathia, glossoptosis, and cleft
palate that results in an obstruction of the airway on inspiration and impeding
feeding.
• The tongue of infants with PRS fall back toward the posterior pharyngeal wall
(glossoptosis) due to receding chin produced by mandibular micrognathia (small
jaw) or retrognathia.
• This causes a serious condition with potentially severe, life-threatening airway
obstruction. If untreated, this problem can lead to exhaustion, cardiac failure,
and ultimately death, especially during the early months of life.
Stomatology. 2014 Nov 20;3(4):30-7. 42

TREATMENT APPROACHES
• Since the major symptoms included glossoptosis, upper airway obstruction and
feeding difficulties are definitely or at least mostly related to micrognathia,
clinicians’ special interest are focused upon growth of and/or lengthen the
mandible in these infants.
• Actually, in the majority of PRS infants, these symptoms can be managed by
placing the infant in a prone position until adequate mandibular growth occurs.
• This traditional treatment method causes the jaw and tongue to fall forward,
opening the airway.
Stomatology. 2014 Nov 20;3(4):30-7. 43

• If this type of treatment fails, the infant then should be considered for other
conservative therapies and/or surgical interventions.
• Conservative interventions can be performed with different orthodontic methods
until adequate mandibular growth occurs.
• Surgical options include tongue-lip adhesion (a procedure to pull the tongue
forward), release of the musculature of mouth floor, mandibular traction, and
mandibular distraction or tracheotomy.
Stomatology. 2014 Nov 20;3(4):30-7. 44

ORTHODONTIC INTERVENTIONS
• Correction of the infant’s micrognathia and associated glossoptosis is possible.
• Besides these treatment alternatives, orthodontists use various palatal plates
and function-stimulating devices which enable the physicians to refrain from
invasive surgery.
• These devices can stabilize the infant’s vital parameters and ensure that it can
be adequately fed during the appliance is placed.
• It is assumed that moving the tongue forward by a device that incorporates a
tongue retaining and stimulating extension part result in mandibular growth
promotion and thus orofacial musculature harmonization.
Kılıç SC, Kılıç N, Oktay H, Kiki A. Pierre Robin sequence from orthodontic and surgical perspective. World Journal
of Stomatology. 2014 Nov 20;3(4):30-7. 45

• This kind of device was firstly introduced by Hotz et al in 1982, and this
appliance was later modified by Buchenau et al in 2007 and called as “Pre-
Epiglottic Baton Plate”.
• This palatal plate was made from a compound soft and hard acrylic covering both
whole palate including alveolar ridges and velar extension approximately 2 to 3 cm
in length, and a wire structure was added to extending acrylic in severe cases.
The position of velar extension was endoscopically inspected and adjusted.
• In 2006, “Tübingen soft palate plate” was described in the German literature by
Brosch et al[37]. This appliance includes three parts: an acrylic palatal plate, an
adjustable velar spur connected to the palatal plate with wires, and two frontal
wire bows to keep the appliance in stable position with extra-oral fixation by
applying adhesive tapes in the cheek and nose area.
Stomatology. 2014 Nov 20;3(4):30-7. 46

• In 2007, Oktay et al introduced a modified
nutrition plate including palatal plate and
adjustable pharyngeal wire extension covered
with an acrylic button.
• In 2011, Bacher et al introduced a new plate
with velar extension, which was quite identical
to the Pre-Epiglottic Baton Plate. This
appliance stimulated mandibular growth and
resolved airway obstruction by forward
positioning of the tongue and mandible by
applying posterior pressure on the root of
tongue.
Stomatology. 2014 Nov 20;3(4):30-7. 47

Cleft lip and palate
• Cleft of the lip and/or the palate is a congenital birth defect, which is
characterised by complete or partial clefting of the lip and/or the palate. The
severity of clefting may vary from the trace of notching of the upper lip to
complete non-fusion of the lip, primary palate and secondary palate.
• Facial clefts are seen due to non-fusion of the facial process. The cleft of the
lip, palate and face may be seen as an isolated birth defect, non-syndromic cleft
or as a part of a syndrome with multiple congenital anomalies later referred to as
‘syndromic clefts’.
Kharbanda OP. Orthodontics: Diagnosis of & Management of Malocclusion & Dentofacial Deformities,(third
edition). 48

• A wide range of severity of the cleft may be observed, and the affected site
may be interrupted by soft bridges (skin or mucosa) and/or bony bridges,
corresponding to the diagnosis of an incomplete cleft. This may occur in either
unilateral or bilateral CLP. Cleft lip and palate can be grouped as
(1) typical/atypical orofacial clefts
(2) syndromic or non-syndromic clefts.
Kharbanda OP. Orthodontics: Diagnosis of & Management of Malocclusion & Dentofacial Deformities,(third edition). 49

Cleft of the lip and primary palate
• The cleft of the upper lip results most commonly from the non-fusion of the
maxillary process with the median nasal process (MNP) during the early stages of
the morphogenesis of the face. Failure of merging between the median nasal and
maxillary processes at the 5th week of embryonic development results in the
cleft of the lip, which usually occurs at the junction of the central and lateral
parts of the upper lip on either side. The clinical expression of the cleft may
vary from a slight notching on the lip to a more severe cleft extending up to
incisive foramen.

Cleft of the secondary palate
• Cleft of the secondary palate develops due to lack of fusion of the right and left
palatine shelves. It can occur in a number of ways:
1. Defective growth of the palatal shelves
2. Delayed or total failure of the shelves to elevate and attain a horizontal position
3. Lack of contact between shelves
4. Post-fusion rupture of shelves
5. Failure of mesenchyme consolidation
Kharbanda OP. Orthodontics: Diagnosis of & Management of Malocclusion & Dentofacial Deformities,(third edition).
51

Cleft soft palate only (CPO)
• Cleft of the palate alone (CPO) is considered as a separate entity and appears to
be under the high genetic influence.
• The cleft of the palate alone is more common in females.
• The cleft may vary in expression of severity from a very mild notching on the tip
of the uvula to a cleft extending the soft palate alone or into the secondary hard
palate up to the incisive foramen.
• Isolated cleft of the soft palate is usually associated with Pierre Robin
malformation and has a distinct U shape while most of the clefts in the palate
make a V-shaped notch.
Kharbanda OP. Orthodontics: Diagnosis of & Management of Malocclusion & Dentofacial Deformities,(third
edition). 52

Submucous cleft palate (SMCP)
• Submucous clefts are clinically invisible and present on the palate as bony
defects but are covered with oral mucosa. Submucous cleft palate (SMCP) is a
subgroup of cleft palate that presents as (1) bifid uvula, (2) translucent zone in
the soft palate an (3) bony notch in the posterior edge of the hard palate.

Syndromic and non-syndromic clefts
• The clefts of the lip, palate and face can be grouped as non-syndromic and
syndromic forms.
• The non-syndromic cleft affected individuals have no other physicalor
developmental anomalies though they may show subnormal growth or other
parameters of physical development.

• The syndromic cleft may appear as a part of multiple congenitalanomalies (MCA).
In multiple congenital anomaly syndromes, cleft patients can be further grouped
into:
1. Monogenic syndrome
2. Chromosomal aberrations
3. Part of an association, or part of a complex of multiple congenital anomalies of
unknown aetiology
4. Teratogenic syndromes
55

Role of an orthodontist
• The orthodontist monitors dental development, occlusion, skeletal problems and
institutes interceptive therapy, dentofacial orthopaedics and prepares for
secondary alveolar bone graft.
• Orthodontist’s expertise in cephalometry and craniofacial growth uniquely
qualifies him or her to monitor craniofacial growth, dental development and
treatment results.

Developmental defects of teeth
• Developmental dental anomalies are marked deviations from the normal color,
contour, size, number, and degree of development of teeth. Local as well as
systemic factors may be responsible for these developmental disturbances
• Such influences may begin before or after birth, hence deciduous or permanent
teeth may be affected. Aberrations in the normal number of teeth include
supernumerary teeth (hyperdontia), i.e. excess teeth or hypodontia (teeth
missing from the normal compliment) while oligodontia is a developmental absence
of six or more teeth excluding the 3rd molars.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent
. 2010 Jul;4(3):263. 58

• Anomalies of shape of teeth include microdontia and macrodontia. Microdontia
refers to teeth that are physically smaller in size than usual and macrodontia in
turn refers to teeth that are physically larger in size than normal.
• Anomalies of shape include dens invaginatus (DI), talon cusp, dens evaginatus,
gemination, fusion, root dilacerations, taurodontism, and concrescence
• DI is an anomaly resulting from invagination in the surface of a tooth crown or
rarely the root and which is lined by enamel and dentin.
• Dens evaginatus is a focal area of the crown, projecting outward and giving rise
to a horn-like protuberance on the affected surface that appears as an extra
cusp.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent .
2010 Jul;4(3):263. 59

• Talon cusp is an accessory cusp usually located on the lingual surface and rarely
on the facial surface of permanent or deciduous incisors. It arises from the
cingulum area, or cemento-enamel junction (CEJ) of maxillary or mandibular
anterior teeth, in both the primary and permanent dentition.4
• Fusion and gemination have been referred to as double teeth which appear as
larger than normal sized teeth.
• Gemination is defined as a single enlarged tooth or joined (double) tooth in which
the tooth count is normal when the anomalous tooth is counted as one.3
• Fusion is defined as a single enlarged tooth or joined (double) tooth in which the
tooth count reveals a missing tooth when the anomalous tooth is counted as one.3
2010 Jul;4(3):263. 60

• Taurodontism is a developmental anomaly of molar teeth in which the body of the
affected teeth is very large and the associated roots are shortened, with
bifurcation near the apex.
• Concrescence is the union of two adjacent teeth by cementum.5 Dilaceration is
an abnormal bend in the root or crown of a tooth. The bend is more frequent in
the root but may be present anywhere along the length of the tooth.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent . 2010
Jul;4(3):263. 61

• A total of 20,182 patients were screened and of these, 350 patients had dental
anomalies. This group was composed of 201 (57.43%) male patients and 149
(42.57%) females.
• Hyperdontia was the most common dental anomaly followed in descending order
by root dilacerations, taurodontism, microdontia, hypodontia, talon cusp, fusion,
dens evaginatus, dens invaginatus, concrescence, gemination and macrodontia.
2010 Jul;4(3):263. 62

Hyperdontia
• Various reports of hyperdontia are mostly in children or the adolescent
population.6 Its prevalence ranges from 0.1 to 3.8%6 but it is increasingly
common in patients with cleft lip and cleft palate. Salcido-garcía et al have
reported a higher prevalence in males than in females.6 This was also noted in
the present study. Among the various supernumerary teeth, mesiodentes are the
most commonly found followed by 4th molars, premolars and maxillary lateral
incisors.6 In the present study, there was a higher occurrence of paramolars
followed by mesiodentes and supernumerary teeth in the anterior region.
Impacted supernumerary teeth had equal occurrence in maxilla and mandible and
occurred in the anterior rather than the posterior region.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent . 2010 Jul;4(3):263. 65

Hypodontia
• This occurs in permanent dentition in 0.3% of the population.7 In the
present study, it was noted that missing teeth constituted 10.6% of all of
the anomalies. Congenitally missing teeth most commonly occur with
maxillary laterals, 2nd premolars and mandibular central incisors and can
be unilateral or bilateral. Radiographs confirm the absence of missing
teeth. The etiology is believed to be hereditary or developmental. In this
study, mandibular central incisors dominated the list compared to
premolars and it was noted more in females. Missing third molars were not
considered in the study sample.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent
. 2010 Jul;4(3):263. 66

• Treatment generally requires a multidisciplinary approach including orthodontic
correction, or prosthetic replacement with a removable or fixed appliance. Age
of the patient, number of missing teeth, carious teeth, and condition of
supporting tissues, occlusion and interocclusal space are the important factors
determining treatment planning.
• Hypodontia and hyperdontia were not noted concomitantly in the present study
unlike the report of Ranta8 where supernumerary teeth and agenesis of teeth
were observed simultaneously more often in permanent dentition than in
deciduous dentition.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population.
Eur J Dent . 2010 Jul;4(3):263. 67

Microdontia
• Teeth commonly affected are maxillary lateral incisors and third molars. The
prevalence of this condition ranges from 0.8% to 8.4% in various populations.1
When lateral incisors are affected, there is a reduction in mesiodistal diameter
and convergence towards the incisal edge and this is referred to as peg shaped
incisors. The condition is largely of genetic origin. In the present study,
microdontia constituted 9.14% of total anomalies with a majority of peg shaped
lateral incisors.

Macrodontia
• Typically only a few teeth are larger than normal. Diffuse true macrodontia is observed in
pituitary gigantism and pineal hyperplasia.1 In this study, only one patient presented with
macrodontia affecting the maxillary central incisors.

Dens invaginatus
• This presents clinically as pit or fissure on the lingual surfaces of anterior teeth.
The classical radiographic appearance of coronal DI is as a pear shaped
invagination of enamel and dentine with a narrow constriction at the opening on
the surface of the tooth.9 The infolding of the enamel lining is more radiopaque
than the surrounding tooth structure aiding easy identification. The crown is
almost always malformed if the coronal invagination is extensive.
• Oehlers et al9 grouped coronal DI into three types according to radiographic
appearance:
• 1. Enamel lined invaginations confined to the crown of the tooth;
• 2. Extending towards the root but not crossing the cemento-enamel junction
(CEJ);
• 3. Penetrating the surface of the root and ‘bursting’ apically or laterally to
produce a second foramen in the root.

• The majority of cases are located in maxilla and in lateral incisors. When
affecting the maxillary lateral incisors, the incidence among several population
groups ranged from 0.25 to 5.1%.9 Following the maxillary lateral incisors, in
decreasing order, the central incisors, premolars, canines and molars are
generally affected. DI involving mandibular teeth is rare. In the present study,
DI accounted for 1.14% of anomalies and types 1 and 2 were noted with maxillary
lateral incisors. There was a higher prevalence in male patients.

• The possibility of the pulp being affected without a clinically detectable lesion as
a result of tortuous lingual anatomy makes DI clinically significant9 since the
enamel is thin and close to the pulp, and so there can be easy involvement. Pulp
sensitivity testing has to be performed if radiographically apical periodontium is
unremarkable in clinically suspicious teeth. If the tooth is vital then it should be
restored to prevent access of the DI to the oral environment. Steffen et al10
have stated that if no entrance to the invagination can be detected and there
are no signs of pulp pathology, no treatment is required other than fissure
sealing or a minimally invasive filling
2010 Jul;4(3):263. 72

• Awareness of this anomaly when present is essential especially in a case of
pulpitis in the absence of any history of trauma or clinical evidence of caries or
restorations. DI with pulpal involvement is usually managed by conventional
endodontic treatment or special endodontic techniques capable of inducing an
apexification if the condition necessitates. Surgical treatment should be
considered in cases of endodontic failure and in teeth which cannot be treated
non-surgically due to anatomical problems or failure to gain access to all parts of
the root canal.
Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental dental anomalies in the Indian population. Eur J Dent . 2010
Jul;4(3):263. 73

Talon cusp
• This is composed of normal enamel and dentin containing varying extensions of
pulp tissue. It may connect with the incisal edge to produce a T-form or, if more
cervical, a Y-shaped crown contour. It is also known by other names such as
interstitial cusp, tuberculated premolar, evaginated odontoma, occlusal enamel
pearl, occlusal anomalous tubercle or supernumerary cusp.

Hattab et al4 classified anomalous cusps into three types based on the degree of
cusp formation and extension:
1. Talon: A morphologically well-delineated additional cusp that prominently
projects from the palatal surface of a primary or permanent anterior tooth and
extends at least half the distance from the CEJ to the incisal edge.
2. Semi talon: An additional cusp of 1 mm or more, but extending less than half the
distance from the CEJ to the incisal edge. It may blend with the palatal surface or
stand away from the rest of the crown.
3. Trace talon: An enlarged or prominent cingula in any of its variants (i.e. conical,
bifid or tubercle-like) originating from the cervical third of the root.

• Its prevalence ranges from less than 1% to 8% of the population11 with a higher
frequency in males than females. The anomaly has a greater predilection for the
maxilla, and maxillary lateral incisors are commonly affected in the permanent
dentition followed by central incisors and canines. In the present study, this
anomaly accounted for 4.28% of dental anomalies and the semi-talon form was
observed.
• Juan et al4 have emphasized that early diagnosis and management of talon cusp is
important to prevent complications such as occlusal interference, compromised
esthetics, caries and periapical pathologies, and periodontal problems. Prevention
of accidental cusp fracture and attrition has also been stressed.

Dens evaginatus
• This is a relatively rare dental anomaly and primarily affects the premolars but can also
occur on molars, canines, and incisors. In premolars and molars, the anomaly is usually seen
on the occlusal surface, while in canines and incisors, it arises from the cingulum area of
the lingual or palatal surface.3 In the present study, dens evaginatus comprised 2.85% of
the total dental anomalies. It is clinically significant as it can lead to occlusal interference
and subsequent loosening or displacement of the involved tooth.3 The tooth may remain
asymptomatic for a considerable period of time.3

Taurodontism
• Teeth affected by this dental anomaly present with elongated pulp chambers and
apical displacement or bifurcation or trifurcation of the roots. This leads to a
greater apicoocclusal height and lack of constriction at the level of the CEJ.2 So the
distance from the bifurcation of roots to the CEJ is greater than the occluso-
cervical distance.
• Taurodontism may be unilateral or bilateral and affects permanent teeth more
frequently than primary teeth. It is commonly observed among the Eskimos and
Natives of Australia and Central America. Taurodontism may be classified as mild,
moderate or severe (hypo, meso and hyper, respectively) based on the degree of
apical displacement of the pulpal floor.2 Mandibular molars are found to be affected
more often than maxillary molars. Its prevalence has been reported to range between
5.67% and 60% of subjects.12,13 In the present study, it accounted for 18% of all of
the anomalies.
• As a taurodont shows wide variation in the size and shape of the pulp chamber with
varying degrees of obliteration and canal configuration, root canal therapy becomes a
challenge.

Fusion and gemination
• These anomalies are also referred to as double teeth, formed as result of total
or partial union in dentin and possibly their pulps. They are known to occur in
both deciduous and permanent dentitions.
• Fusion may be partial or complete and may present with two independent root
canals or less often, a single root and one or two pulp chambers.14 As a result,
the tooth may be of normal size or larger than normal. Fusion of central incisors
and canines is more frequent than that of lateral incisors and canines. The
prevalence ranges from 0.5% to 5% based on geographic, racial or genetic
factors.

• Gemination is an incomplete division of one tooth germ, resulting in the formation
of two partially or completely separated crowns formed on a single root.2 It is
more frequent in the anterior teeth, but can also affect molars and bicuspids. It
has a prevalence of 0.5% and 0.1% in deciduous and permanent dentitions,
respectively.
• In the present study, fusion accounted for 4.85%, and gemination constituted
0.28% (only one patient) of all of the dental anomalies. Fusion was observed to
occur unilaterally in accordance with other studies.15 Mandibular teeth were
affected more than maxillary. Fusion can be suspected when the number of teeth
in the arch is found to be reduced and/or two roots are seen radiographically.

• Double teeth will appear similar clinically and are larger than normal teeth, but
by definition fusion must involve dentin.2 Gemination can usually be distinguished
from fusion by the presence of a full compliment of teeth and an incompletely
divided tooth.
• Double teeth may adversely affect esthetics, and may lead to dental crowding
and difficulty in eruption of adjacent teeth. Treatment consists of managing
asymmetry, either by extirpation of the unwanted dental portion in conjunction
with root canal therapy, or restoration of the exposed area. Orthodontic
intervention completes the treatment plan.

Accessory roots
• These are commonly known to occur in mandibular canines, premolars and molars
(often in 3rd molars).16 There are no reported studies on the prevalence or
occurrence of accessory roots in different populations except for individual case
reports.16 In the present study, accessory roots were noted in mandibular
premolars and 1st molars with higher numbers in males and comprising 2% of the
total anomalies. This abnormality is a definite hindrance for successful
endodontic treatment leading to perforations and also poses difficulty in
extractions. The radiographic signs of accessory roots include double periodontal
spaces on one side of the root, periodontal space crossing roots and abrupt
diminution of the root canal spaces.

Concrescence
• The incidence of concrescent teeth is reported to be highest in the posterior maxilla. In
the present study, only four patients had concrescence constituting 1.4% of all of the
dental anomalies. It may influence surgical procedures, periodontal, endodontic and even
orthodontic treatment.

Dilacerations
• These are thought to arise secondary to trauma during tooth formation, altering
the angle between the tooth germ and the portion of the tooth already
developed.2 Occasionally, the bend is created by pressure from adjacent cysts,
tumors or odontogenic hamartoma. Frequently, the affected teeth are the
maxillary incisors followed by the mandible anteriors. In the present study,
dilacerations of the roots comprised 22.5% of the anomalies. It was noted more
in males than in females. The severity of angulation seems to be related to the
age of the patient, and the direction and degree of the force applied. It may
produce delayed eruption or difficulties during root canal therapy or extraction.
Early recognition on preoperative radiographs will minimize the problems.

Developmental disturbance of the
Jaws
AGNATHIA
• Also called hypognathous .
• It is total absence of either one or both the Jaw bones.
• It is a rare condition.
Ghom G.A:Textbook of oral medicine, (second edition);153-154 85

• Clinical features:
• Absence of mandible : If mandible is absent, the upperpart of the face may be
normal and the skin of the lower part will be continuous with the suprasternal
integument
• Hyoid bone is sometime absent
• Vertical slit : In place of buccal orifice, vertical split may be present
• Deformed ear
• Associated abnormalities : There may be absence of ears, cleft palate ,
hypoplastic tongue, microstomia, narrow auditory canal.
• Management
• • Surgical reconstruction—surgical reconstruction though it is difficult it should
be carried out.
Ghom G.A:Textbook of oral medicine, (second edition);154 86

Micrognathia
• Micrognathia is severely deficient jaw, which most commonly affects the mandible. It is
common to see individuals having a very small mandible.
• Types
1. Apparent micrognathia- this is not due to abnormality of small jaw, in terms of size but
rather to an abnormal positioning or abnormal relation of one jaw to another, which
produces illusion of micrognathia.
2. True micrognathia—It is due to small jaw. It is again classified as
• Congenital
• Acquired

Clinical Features
• Micrognathia of maxilla—it is due to deficiency of premaxillary area and patient
with this deformity appears to have the middle third of face retracted.
• True mandibular micrognathia—it is uncommon and patient appears clinically to have
severe retrusion of chin, steep mandibular angle and deficient chin button.
• Signs—micrognathia is one of the causes of abnormal alignment of teeth. This can
be seen by observing the occlusion of teeth. Often, there will not be enough room
for the teeth to grow. If the upper jaw is short, then, occlusion may be abnormal.

• Symptoms—in true micrognathia, the jaw is small enough to interfere with
feeding of the infant and may require special nipples in order to feed adequately.
There may be difficulty in respiration. Due to the small size of the arch, the jaw
is not able to accommodate the tongue, which is forced back into the oropharynx,
blocking the air passage.
• Syndromes associated with micrognathia—Pierre Robin syndrome, Hallerman-
Streiff syndrome, trisomy 13 ,trisomy 18, Turner’s syndrome, Treacher-Collins
syndrome and Marfan’s syndrome.

• Management
• Orthognathic surgery—this is recommended treatment modality for micrognathia.
This surgery is followed by orthodontic appliance to correct malocclusion.
• Small maxilla—if upper jaw is short, then it can be corrected with surgical
orthodontic treatment by properly aligning the teeth and then moving surgically and
elongating the short maxilla, in order of three to four millimeters of the upper
central incisors to show when an individual is smiling.
• Small mandible—small mandible can be corrected, depending on the degree of
deformity and problem, advancement of mandible and chin surgically.

Macrognathia
• It refers to the condition of abnormally large jaws. It is also called as
‘megagnathia’. Macrognathia literally means a large jaw. The mandible is most often
affected in this case giving rise to a condition where the bone protrudes.
• Clinical Features
• Prognathism—mandibular protrusion or proganthism is common occurrence, which is
due to disparity in the size of maxilla to mandible and posterior positioning of
maxilla in relation to the cranium.
• Mandible—mandible is measurably larger than normal. Increased mandibular body
length.

• Gummy smile—in certain patients with congenital abnormalities, there may be
elongation of maxilla. There is much “show” when the patient smiles, so that
there is a so-called “gummy” smile. This is due to the upper jaw being too long.
• Ramus—large ramus which forms less steep angle with body of mandible.
• Chin—there is prominent chin button.
Management
• Osteotomy—resection of portion of mandible to decrease the length, followed by
orthodontic treatment.

Developmental defects of tongue
Aglossia and Microglossia
Definition
• Aglossia—it is the complete absent of tongue at birth.
• Microglossia—it is the presence of small rudimentary tongue.
Ghom G.A:Textbook of oral medicine, (second edition);537
93

• Symptoms—patient encounters difficulty in eating and speaking.
• Signs—patient may have high arched palate and a narrow constricted mandible.
• Airway problems—there may be an airway obstruction, due to negative pressure
generated by deglutition and inspiration.
• Syndrome associated—oromandibular limb hypogenesis syndrome (hypodactylia) and
hypomelia and Pierre Robin syndrome.
• Management
• Non-surgical technique such as positioning, nasogastric intubation and temporary
endotracheal intubation can be carried out to prevent airway obstruction.

Macroglossia
• Macroglossia is tongue enlargement, which leads to functional and cosmetic
problems. Although, this is relatively uncommon disorder, it may cause significant
morbidity. Normal speech and swallowing reflexes require normal tongue anatomy
and its functions. Swallowing begins as the tongue mixes food with saliva to form
a food bolus, which is then propelled into the pharynx by the tongue. Articulation
also depends on the tongue’s ability to alter the impedance of air and change the
resonant characteristics of the upper airway. In macroglossia, increased tongue
bulk may impair these functions.

Classification
1. Congenital
2. Acquired
3. Hypertrophic—in it, muscles of the tongue are hypertrophic. It usually occurs in
mentally retarded patients.
4. Inflammatory—it may involve the tongue partially or completely. It is due to
various causes like syphilitic, Ludwig’s angina, etc.
5. Neoplastic—it can be based on benign and malignant tumors.
6. Relative macroglossia—it is a condition, in which a normal sized tongue appears
abnormally large, if it is particularly enclosed within a small oral cavity.
7. Apparent macroglossia—it is a condition where the tongue appears large due to
poor muscular control of the tongue, although there is no increase in the bulk of
tongue tissue.

Clinical Features
• Age—macroglossia is most prominent in infants, but tongue size may remain above
normal in childhood and adolescence. As hyoid descends with age, macroglossia may
improve.
• Symptoms—patient complaint of noisy breathing, drooling of saliva and difficulty in
eating. Patient may get recurrent upper respiratory tract infection as tongue is
usually protruded and mucosal drying occurs. The enlargement is generalized and
may cause variety of difficulties with speech, feeding and airway problems.
• Signs—It may produce displacement of teeth and malocclusion, due to the strength
of muscles involved and pressure exerted by the tongue on teeth.
• Crenated lateral border—crenation or scalloping of the lateral borders of the
tongue; the tips of scalloping fit into the interproximal spaces between the teeth.
• Syndrome associated—it is associated with syndromes like Beckwith’s hypoglycemic
syndrome which includes neonatal hypoglycemia, mild microcephaly, umbilical hernia,
and fetal visceromegaly and postnatal somatic gigantism.

Management
• Orofacial therapy—it uses a palatal device to stimulate muscular tone and proper
tongue position.
• Surgical management—majority of the cases of macroglossia are treated surgically.
Indications for surgery include airway obstruction, speech difficulties, dysphagia
and cosmetics. The procedure of choice is partial glossectomy. Surgical goal is to
reduce the tongue size and thus improve the condition.
• Removal of cause—removal of primary cause should be done.
• Orthodontic treatment—correction of the dental arch deformity and malocclusion
by orthodontic treatment.
• Speech therapy—correction of defective articulation by speech therapy.

Ankyloglossia
• It is also called as ‘tongue-tie’. It occurs due to incomplete degeneration of cells
while the body of tongue is freed. In it, tip of tongue remains tide to floor of
mouth. It is a condition in which the lingual frenulum is either too short or
anteriorly placed limiting the mobility of the tongue. Reports of partial
ankyloglossia affecting several generations, suggest a possible genetic basis for the
minor variation in the attachment of the genioglossus muscle. It may be traumatic
or congenital.
• Types
• • Complete—fusion of tongue and the floor of mouth.
• • Partial—short lingual frenum.

Clinical Features
• Symptoms
• Restricted tongue movement—it may limit the movement of the tongue.
• Feeding problems—In extreme cases of ankyloglossia, nursing and feeding
problems can occur. Poor sucking and inability to chew some food also occurs.
• Speech defect—it was felt that tongue-tie was associated with speech
abnormalities, especially lisping and inability to pronounce certain sounds and
words viz t, d, n, l, as, ta, te, time etc.
• Tongue biting—in some cases, recurrent tongue biting is also reported.

•Signs
• V shaped notch—when there is an attempt to stick the tongue out, there may be a V
shaped notch at the tip Physical examination will easily demonstrate the short or
anteriorly placed lingual frenulum
• Anterior open bite—patients have midline mandibular diastema and inability to clean
the teeth and lick the lips with tongue.
• Periodontal problems—due to high frenum attachment some patient may face
periodontal problems.
• Syndromes associated—ankyloglossum superius syndrome, Rainbow syndrome,
Fraser’s syndrome and orofacial digital syndrome.

• Management
• Counselling—physician education, parental education and reassurance should be
given to the patient.
• Surgery—indications for surgery, i.e. frenectomy are as follows:
• If complete fusion of tongue is present then it requires surgery.
• When nursing and feeding become a problem, surgery is indicated.
• Children between 2-4 years, with poor development of speech and anxious
parent’s desire for the necessary treatment.
• In cases where tongue-tie has recurred after snipping.

Cleft Tongue
It is also called as ‘bifid tongue’. It is the condition in which there is cleavage of the
tongue due to lack of fusion of the lateral halves.
• • Incidence—completely bifid or cleft tongue is rare. It is due to lack of merging of
lateral swellings of the organ.
• • Appearance—partially cleft tongue is manifested as deep grooves in the midline of
dorsal surface

• Symptoms—food debris and microorganisms may collect in the base of cleft and
cause irritation.
• Syndromes associated—seen with orofacial-digital syndrome, with thick fibrous
bands in lower anterior mucobuccal fold, which eliminate the sulcus and is
associated with clefting of hypoplastic mandibular alveolar process.
• Management
• Regular cleaning of the tongue should be carried out.

Hyperplasia of condyle
Clinical features:
Unilateral:
• Mandibular enlargement
• Facial asymmetry
• Shift in midline
• Malocclusion
Bilateral:
• Anterior cross bite
• Relative microdontia
• Obtuse mandibular angle

• Condylectomy- to improve function and esthetics
• Maxillary osteotomy- in cases of compensatory maxillary growth
• Orthodontic therapy- to treat cross bites
Management

Hypoplasia of condyle
Clinical features:
Unilateral
• Appearance of face- affected side: body of mandible is short
unaffected side: elongation of body of mandible
• Shifting on affected side
• Malocclusion
• Delayed eruption of teeth. In some cases it will cause impaction and uneruption.
• The external ear maybe small, deformed, partially or completely absent.
Ghom G.A:Textbook of oral medicine, (second edition); 606-7
107

Bilateral
• Micrognathia
• Delayed eruption of teeth
• Class II malocclusion
Management
• Surgical – directed towards increasing the length
and bulk of the bone.
• Orthodontic treatment to correct the
malocclusion.
Ghom G.A:Textbook of oral medicine, (second edition);607
108

Agenesis of the condyle
Clinical features:
• Asymmetry of face
• Anterior open bite
• Eccentric movement
• Altered occlusion
• Shift of mandible towards affected side during opening in unilateral type.
• Associated anomalies like under-developed ramus absent external ear.
Management:
• Maintenance of dental health
• Osteoplasty
Ghom G.A:Textbook of oral medicine, (second edition);607-8
109

Double Condyle or Bifid Condyle
• In this, double headed mandibular condyle is seen. Condyle is divided by an
anteroposterior groove.
• Age and sex distribution—it is noticed at any age and is more common in females
than male with a ratio of 3:2.
• Location—it is usually unilateral. But bilateral occurrence can also be seen.
• Symptoms—limitation of opening of mouth, a small lateral deviation. In some
cases, click of pop is heard while patient open the mouth.
• Signs—lateral movement of mandible is limited.
Ghom G.A:Textbook of oral medicine, (second edition);607-8
110

• Radiological Features
• Bilobed appearance—radiographs will show bilobed appearance of the condyle
• Separate glenoid fossa—there may be two separate glenoid fossa.
• Management
• Surgical—as such no treatment is necessary, but if it is causing some problems surgical
approach is carried out.

Coronoid Hyperplasia
• It is rare developmental disorder affecting the coronoid process of mandible.
• • Age and sex distribution—it is seen in 2nd decade of life and most commonly
encounter in males in the ratio of 5:1.
• • Unilateral coronoid hyperplasia—in unilateral type, there is restriction of
mandibular movement. It occurs due to enlarged coronoid may impinge on the
zygomatic surface causing reduction in the mandibular movement. There is also
deviation of mandible on the affected side.
• • Bilateral coronoid hyperplasia—in this, limitation of movements occur which
become more severe as the age progress.

• Radiological Features
• Unilateral—In this case irregular nodular growth of the tip of the coronoid process
is seen.
• Bilateral—there is symmetrical enlargement of coronoid on both sides.
• Management
• Coronoidectomy—it is carried out to remove the elongated process of coronoid.

The orthodontist and complex
craniofacial anomalies
• Despite anatomical abnormalities, there is no need to treat a craniofacial anomaly
unless it is, or will become, a real problem for the patient.
• There must be either an interference with function or an effect on facial
esthetics that interferes with psychosocial development.
• Many craniofacial anomalies do not cause a functional problem.
• Indeed, in a society less obsessed with facial esthetics, there would be no
problem associated with “different” faces.
Ross B. The orthodontist and complex craniofacial anomalies. American Journal of Orthodontics and Dentofacial
Orthopedics. 2001 Feb 1;119(2):92-4. 114

• The severe expression of hemifacial macrosomia may unilaterally have a condyle
and ramus that are severely dysplastic or even absent, no temporal fossa, and
severely hypoplastic or virtually absent muscles of mastication.
• Yet such patients have no associated pain or discomfort, can chew and swallow
comfortably, can speak with normal articulation and nasal resonance, and can
breathe adequately.
• Apart from the loss of hearing, there may be no dysfunction except in the
narrowest of definitions: the mandible and temporomandibular joint do not
function in a “normal” way.
Ross B. The orthodontist and complex craniofacial anomalies. American Journal of Orthodontics and
Dentofacial Orthopedics. 2001 Feb 1;119(2):92-4.
115

• Therefore, the primary purpose of treatment is to establish optimum facial
esthetics, in the course of which there is usually very favorable jaw(s)
repositioning that permits the orthodontist to achieve excellent occlusal
function.
• Thus, planning treatment begins with the identification of
• (1) the desired facial esthestics,
• (2) the skeletal and soft tissue alterations necessary to make the desired
changes, and
• (3) the dental changes required.
Ross B. The orthodontist and complex craniofacial anomalies. American Journal of Orthodontics
and Dentofacial Orthopedics. 2001 Feb 1;119(2):92-4. 116

THE TEAM APPROACH
• Complex craniofacial anomalies generally require treatment by many different
specialists. This seems to work best when a dedicated team is organized and
treatment is coordinated.
• The orthodontist is an essential member of any craniofacial team.
• The role of the orthodontist on the team is to:
1. Help determine which craniofacial structures are abnormal in the affected patient.
2. Determine the facial growth pattern and predict the future morphology.
3. Estimate the effect that various treatment modalities, particularly surgery, would
have on subsequent growth and advise on the appropriate nature and timing of
treatment.
4. Plan with the surgeon the desired skeletal and soft tissue alterations.
5. Prepare for the orthognathic component of the surgery by manipulating the teeth
and alveolar process, and complete orthodontic corrections after the surgery.
6. Become involved in clinical research on facial morphology, growth, and response to
treatment.
Ross B. The orthodontist and complex craniofacial anomalies. American Journal of Orthodontics and Dentofacial Orthopedics. 2001 Feb 1;119(2):92-4.
117

Orthodontic management of orofacial problems in young
people with impairments: case reports
CASE-1
• GC was a 13-year-old girl with cerebral palsy as a
consequence of surgery as a neonate for aortic stenosis.
• She had profound learning disability and epilepsy. GC
presented for an orthodontic assessment because of
severe, self-inflicted trauma.
• The patient’s lip lesion had been monitored by a dentist
for a period of months, and he referred her for a biopsy
when the lip lesion failed to heal.
Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial problems in young people with
impairments: review of the literature and case reports. International journal of paediatric
dentistry. 2005 Sep;15(5):355-63. 118

• The biopsy revealed no significant pathology, only
the features of a chronic ulcer that was probably
related to a crush injury of the muscles.
• Placement of upper and lower soft splints, retained
by dental cement, failed to prevent the ongoing
self-inflicted trauma.
• After occlusal analysis, showing a Class II Division 1
malocclusion with a lower lip trap that was
exacerbating the lip trauma, a decision was taken to
offer orthodontic care in order to procline the
lower incisors and so prevent further trauma.
Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial problems in young people with impairments: review of the literature and
case reports. International journal of paediatric dentistry. 2005 Sep;15(5):355-63. 119

• Under outpatient general anaesthesia, the LLE (75) was
extracted, the cement used to retain the splints
removed from the upper and lower incisor and canine
teeth, and upper and lower alginate impressions were
recorded.
• A lower fixed appliance was placed with 0·018
preprogramed brackets on the lower first premolar
teeth (34, 44) and GAC (GAC International, NY, USA)
brackets were applied to the lower six anterior teeth,
and a 018 Australian alignment arch wire was fitted.
.
Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial problems in young people with impairments: review of
the literature and case reports. International journal of paediatric dentistry. 2005 Sep;15(5):355-63
120

• This was all provided under 500 mg Amoxicillin IV with a follow-up oral dose 6 h
later. At review, 6 days later, the lip ulcer was healing well, but a small ulcerated
area had appeared opposite the LR3 (43).
• The parent was shown how to apply white wax to the bracket opposite this area
and 200 mL 0·15% benzydamine hydrochloride spray was prescribed for
application to the ulcerated area.
• The arch wire was changed at approximately 6-week intervals without recourse
to sedation.
• The lower fixed appliance was debonded 10 months later and a bonded retainer
was fitted.
• This was undertaken at the same time as the removal of a retained primary
canine (53) and a carious first permanent molar (26).
• At review, the ulcerated area opposite the upper right lateral incisor (12) was
healing and the latter was smoothed with a Soflex disc.
Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial problems in young people with impairments:
review of the literature and case reports. International journal of paediatric dentistry. 2005 Sep;15(5):355-63. 121

Case-2
• SSV was a girl with Rubinstein–Taybi syndrome.
• This condition was first documented in 1963 when Rubinstein and Taybi observed
the combination of broad thumbs and halluces, characteristic craniofacial
dysmorphism, growth retardation, and learning difficulties.
• Oral and dental features include: talon cusps, a high arched palate, mild
micrognathia, and less frequently, bifid uvula, submucous cleft, bifid tongue,
macroglossia, short lingual frenum, natal teeth and thin upper lip.

• SSV had a high, narrow upper arch, a Class III incisor relationship, and severe
anterior crowding in both the upper and lower arches.
• The patient had moderate learning difficulties and could not cope with routine
dental treatment.
• She had required general anesthesia for clinical examination and restorative
treatment as an inpatient since the age of 7 years.
• At the age of 12, a provisional orthodontic plan was made to extract the buccally
placed upper canine teeth (13, 23) as well as the LL1 (31) in order to relieve
crowding and then align the upper arch.

• The extractions were carried out under general anesthesia and the UL6 (26) was
removed at the same time because of extensive caries.
• At a review appointment, the patient had a fixed appliance placed on 11,
12,14,15,21,22,24.
• The patient was now very cooperative and keen to maintain good oral hygiene.
• The fixed appliances were maintained for 6 months until levelling and aligning of
the upper arch was obtained.
Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial problems in young
people with impairments: review of the literature and case reports. International journal
of paediatric dentistry. 2005 Sep;15(5):355-63. 124

• A good deal of our uncertainty in the diagnosis and prognosis of
unacceptable facial relationships relates to our lack of knowledge of their
natural history.
• There has been a tendency to abstain from corrective measures until the
growing period has ended, when adaptation of regional organs to the
abnormality is complete and the options for treatment are reduced.
• If an undesirable relationship is established early and persists, correctional
measures could be appropriate at any time during the growing period.
CONCLUSION

• On the basis of the biologic, interdisciplinary approach which
constitutes "orthocephalics," the optimal rationale for diagnosis and
treatment planning in severe craniofacial skeletal anomalies will have
at least three phases or goals of treatment:
1. The earliest possible diagnosis and elimination of the pathologic
process responsible for the skeletal anomaly. The main objective at
this time is to focus on identification of the pathologic stimulus.
Early interception of the pathognomonic process which is a way of
restoring the capacity for subsequent growth at that site is the
first goal.

2. The interception and reversal of secondary skeletal deformities by means
of force-induced articular and skeletal remodeling. The objective at this
stage is to focus on the spectrum of skeletal deformities that constitute
biologic adaptations to the pathologic defect. The therapeutic forces
should be applied directly to the skeletal sites that require remodeling in
order to achieve a functional balance.
3. Supplementation of previous treatment by means of minor plastic and
reconstructive surgery aimed at cosmetic rather than functional
correction.

References
• Ghom G.A:Textbook of oral medicine, (second edition)
• Premkumar S.: Textbook of craniofacial growth ,( 1st edition)
• Guttal KS, Naikmasur VG, Bhargava P, Bathi RJ. Frequency of developmental
dental anomalies in the Indian population. Eur J Dent . 2010 Jul;4(3):263.
• Ross B. The orthodontist and complex craniofacial anomalies. American
Journal of Orthodontics and Dentofacial Orthopedics. 2001 Feb
1;119(2):92-4.
• Hobson RS, Nunn JH, Cozma I. Orthodontic management of orofacial
problems in young people with impairments: review of the literature and case
reports. International journal of paediatric dentistry. 2005 Sep;15(5):355-
63.
128

• Kharbanda OP. Orthodontics: Diagnosis of & Management of Malocclusion &
Dentofacial Deformities,(third edition).
• Kılıç SC, Kılıç N, Oktay H, Kiki A. Pierre Robin sequence from orthodontic
and surgical perspective. World Journal of Stomatology. 2014 Nov
20;3(4):30-7.
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