Anomilies Related to Oral and Para-oral Structures

Prof .Dr.Amal M. El Deeb

Prof.of Oral Pathology Faculty of
Dentistry,Umm Al Qurra
University,Makka,SA

Anomalies
related to
oral & para-
oral
structures

• Congenital : Existing since before birth or at
birth; dating from birth. Congenital malfor-
mations are anatomical or structural abnor-
malities that are present at birth, though they
may not be diagnosed until later.

• Hereditary: Transmitted from ancestors or
parents to a child. Same as genetic.

• Genetic : Transmitted from one generation to
another through genes, same as hereditary.

• Autosomal : A trait transmitted by a gene
carried on an autosome ( any member of the
22 paired chromosomes other than the X and
Y sex chromosomes ).

• Sex-liked: A trait transmitted by a gene
carried on one of the sex chromosomes.

• Dominant : A dominant gene is one which
will produce its effect when present in either
heterozygous or homozygous condition (
when only one or both alleles are affected ).

• Recessive : A recessive gene is one which
will produce its effect only when present in a
homozygous condition ( only when both
alleles are affected ).

• Developmental : Characterized by , or belonging to
the process of development. Used here to designate
a condition or disease caused by some non-
hereditary error in the process of development.

• Acquired : A term used to describe a condition, habit
or other characteristic which is not present at birth ,
but which develop in the individual by reaction to
some environmental factor ( to acquire is to obtain ).

• Translocation : Transfer of chromosomal material
between chromosomes. This involves breakage of
both chromosomes with repair in an abnormal
arrangement.

• Inversion : This arises through two chromosomal
breaks with inversion through 180 of the segment
between the breaks.

• Deletion : This arises from loss of a
portion of a chromosome between two
break points or as a result of a parental
translocation.

• Teratogen : Any agent that can induce
or increase the incidence of a
congenital malformation. An agent
capable of causing abnormal
development prior to birth .

**According to the site:-
(1)Anomilies of the jaws.
(2)Anomilies of the palate.
(3)Anomilies of the lips.
(4)Anomilies of the gingivae.
(5)Anomilies of the tongue.
(6)Anomilies of the salivary glands.
(7)Anomilies of the lines of fusion.
(8)Anomilies of the teeth.

Developmental
Disturbances of the
jaws

Agnathia

• ** Very rare congenital defect.
• ** it means complete absence of
mandible or maxilla.
• **it is more common in mandible
(mandibular agnathia.).
• **In maxilla:- the maxillary process or
the premaxilla may be abscent.

Micrognathia
** Means small arch either the
maxilla or mandible.
**It may be either:-
#True micrognathia:- that
the arch is really small in
size.It may be congenital or
acquired.
#False micrognathia:- that
there is abnormal postioning
or relationship of one jaw to
the other or to the skull.

Pierre-Robin Syndrome
• It is characterized by :-
• **Hypoplasia of the mandible.
• **Falling back of the tongue
(glossoptosis)  cyanosis & asphyxia.
• **Frequently, an associated cleft palate &
external ear defects.
• **Associated bifid tongue may be present.
• ** Other systemic findings as congenital
heart defects, skeletal anomilies, occular
lesions.
• **Mental retardation may be found.

Macrognathia
• The condition of
abnormally large jaw.
• It may be associated
with:-
**Some diseases of
bone as Paget`s
disease.
**Hormonal
disturbances as
acromegally.

4- Torus mandibularis.
• It is a common exostosis that
develops along the lingual aspect of
the mandible above the mylohyoid
line in the region of the premolars.

• Mostly it occurs bilateral,
asymptomatic single nodules
although multiple lobules are not
uncommon.
•
• It appears to be more common in
Asian and Eskimos.
• On periapical radiographs, it shows
as a radiopacity superimposed on
the roots of the teeth.

Developmental
disturbances of
the lip

1-Congenital lip pits
• Congenital lip pits may occur in either upper or
lower lip.
• It affects more commonly the lower lip than the
upper.
• Lip pits are usually bilateral depressions on the
vermillion border.
• Lip pits, particularly those of the lower lip, are
closely related to cleft lip and cleft palate.
• The pits represent blind sinuses that descend
through the orbicularis muscle to depth of 0.5 to 2.5
Cm and communicate with the underlying minor
salivary glands.
• They often extrude viscid saliva either
spontaneously or upon pressure.

2- Congenital fistulae of the lips.
• It is an extremely uncommon condition. It
is characterized by two fistulae in the
lower lip which present two orifices on the
vermillion border, positioned one on each
side of the midline.
• The fistulous tract may be explored with a
very fine probe and small amounts of
mucous may be expressed.
• The cause in unknown.

3-Commissural lip pits
• These are an entity very closely related
to lip pits, but occur at the lip
commissures, appears as unilateral or
bilateral pits at the corner of the mouth
on the vermillion surface.
• Treatment:
• Surgical excision of these
various pits has been recommended.
•

5- Cheilitis glandularis
apostematosa.
• This is an uncommon condition of unknown
etiology in which the lip becomes enlarged,
firm and everted exposing the openings of the
labial mucous glands.

• The labial mucous glands become enlarged
and nodular and the orifices of their ducts
become inflammed and dilated giving the
lateral mucosa a red macular appearance.
•
• The condition affects males much more
commonly than females, and painless.
Malignant transformation has been reported.

6- Cheilitis granulomatosa.
Melkerson Rosenthal
Syndrome
• It includes Cheilitis granulomatosa,
recurrent facial paralysis as well as a
fissured tongue.
• Cheilitis granulomatosa :-It is a disorder
characterized by a chronic, rather firm
swelling, affecting usually one lip but
sometimes both.
• Usually the upper lip is affected ,
occasionally the swelling affects the
cheeks, fore head, chin or tongue.
• Histopathology:
• **a chronic inflammatory cell infiltrate.
• ** There are scattered granulomata
containing some epithelioid cells,
• **few giant cells are sometimes also
present.

Hereditary intestinal polyposis.
(Peutz-Jegher's syndrome
• This disease is a relatively rare and inherited
as an autosomal dominant trait. It is of
significance to the dentist because of its
oral manifestation through which an early
diagnosis can be established.
•
• Clinical features:
• The melanin pigmentation of the lips and
oral mucosa appears as small brown
speckles measuring (1-5 mms) in diameter
and mostly on buccal mucosa, gingivae,
hard palate, neck, on the face the spots are
grouped around the eyes, nostrils and lips.

• The polyps are distributed through the
entire intestine especially small intestine,
are hamartomatous and are not
premalignant, but may lead to serious
intestinal obstruction and death.

Developmental
disturbances of
the palate

Torus palatinus
• **It appears as a single or multiple
bony excrescences
• **This is a developmental, frequently
hereditary malformation about the
midline of the palate.
• **They are sometimes flat and
fusiform and sometimes lobulated and
nodular.

• **The covering mucous membrane is
intact but thin. Lesions are composed
either of compact bone or a core of
cancellous bone covered by a layer of
compact bone.

4- Cleft lip and palate
• Cleft:- is a defect which results from failure of
fusion of any of the facial processes.
• **The most common in the upper lip and palate
region.
• **Clefts are rare in the lower jaw.
• **The incidence of cleft lip and palate varied in
different parts of the world. It is generally taken to
be about (1:800 – 1000) live births.
• **Clefts are described as pre-alveolar (simple),
alveolar and post-alveolar according to their
occurrence in the lip, alveolus or palate
respectively.

• **The lesion may range from being:-
• a simple notch of the lower border of the lip to----
-a broad cleft extending from the lower
border of the lip to the floor of the nose.

• **An accompanying cleft of the alveolus and

• Complete double clefts:- a portion of the lip
(globular process) is isolated on the
collumella.
• This medial portion is small compared to the
lateral elements of the lip, is devoid of muscle
and shows no philtrum. Median clefts of the
upper lip are rare, and as with lateral clefts,
they vary in degree.

• In the palate,
• **Clefts extends forwards from the uvula and
may involve the soft palate only or
• The hard palate may also be involved to the
incisive foramen, or
• There may be a complete unilateral cleft
extending from the uvula to the incisive
foramen in the midline then deviating to one
side and meeting the alveolar process in the
area of the lateral incisor and then into the lip,
or
• there may be a complete bilateral clefts
extending forwards bilaterally from the
incisive foramen to the alveolus and lip.
**Should the alveolus be bilaterally involved,
the premaxilla remains suspended from the
primitive nasal septum.

Complications of cleft lip and
• palate
• Infants are unable to suckle well and present feeding problems ,
they have a tendency to aspirate food and are therefore susceptible
to respiratory diseases.

• Infection of the nasopharynx which occasionally tracks up the
pharyngotympanic tubes, leading to otitis media and deafness.

• Older children have esthetics as well as social and psychological
problems.

• Defects in speech is being marked in the pronouncation of the
letter K&G for the articulation of which the back of the tongue
meets the soft plate.

• TREATMENT:-** It is desirable to treat such individuals at an early
age.
• ** Clefts of the lip are usually treated by surgical closure in the first
few months of life ,
• ** Clefts of the palate at about 18 months of age.
• **In some instances surgery is only partially successful and the
cleft must be treated by prosthetic appliances.

DEVELOPMENTAL
DISTURBANCES OF
ORAL MUCOSA & LINES
OF FUSION

Fordyce's spots or Fordyce's
granules.
• Sebaceous glands are frequently included
in the line of fusion between the maxillary
and mandibular processes
• Site:- *Are found just beneath the buccal
mucosa along the line of occlusion of the
teeth.
• *They may be also seen opposite the last
molar, around the parotid papillae and
sometimes near the angle of mouth
• *May also be seen on the exposed
vermilion border of the lip as extensions
from the skin beneath the lip mucosa
• .Usually occur bilaterally
• singularly or in groups as small (1-2mms)
slightly elevated colored spots.
• They produce a yellowish rough plaque.
• . About 30% of the adult population have
these inclusion.

White sponge nevus.
White folded gingivostomatitis (
• It is a congenital abnormality, yet it
was suggested that it is a type of nevi
on the basis that is limited to the
buccal, rectal, and vaginal mucosa,
and the upper part of the anal canal.
• The mucosa appears thickened and
folded with soft or spongy texture and
peculiar white opalescent character.

• Microscopically:
• The epithelium is thickened but the
basal layer is intact, there is
intracellular edema of spinous cell
layer. The cells of the spinous cell
layer show pykontic nuclei and
parakeratosis in the form of plaques.
There is mild inflammatory cell
infiltration of the submucosa.

Bohn's nodules or (Epestein's
pearls)
• Rare small firm white or
grayish white lesions may be
seen on the palate or the
alveolar mucosa of new born
infants. They are usually
multiple but do not increase
in size.
• Microscopically:
• Reveal small superficial
keratin containing cyst
which are lined by stratified
squamous epithelium and
often spontaneously shed
within four weeks, but it may
be surgically removed.

Developmental
Disturbances of the
tongue

Aglossia

• ** A condition in which the tongue
being completely absent at birth.

• **when present is always
accompanied by cleft palate.

Microglossia

Is a rare congenital abnormally
manifested by the presence of a
small or rudimentary tongue.

Macroglossia
• Means an enlarged tongue, may be either:-
•
• Congenital macroglossia is due to an over-
development of the musculature.

• Secondary macroglossia may occur due to
• * Tumor of the tongue (lymphangioma or
haemangioma).
• * Neurofibromatosis.
• * Malignant neoplasms- Blockage of the
lymphatic vessels.
• * Acromegaly due to hyperpituiterism in
the adult.
• *Cretinism or congenital hypothyroidism.
• *Amyloidosis. is the deposition in the
tissue of an abnormal protein with
characteristic staining properties, it can
result from over production of
immunoglobulin light chains,
usually by multiple myeloma.

Down's syndrome
Down's syndrome is the most common clinically
• recognizable syndrome with severe learning difficulty.

• It is caused by trisomy of chromosome 21 giving a total
• complement of 47 chromosomes instead of 46.

• This is usually caused by failure of the chromosomes to
separate during meiosis in the ovum, a defect closely linked to
• maternal age.
•
• The overall incidence is 1 in 700 live births but the risk rises to
1 in 25 in mothers aged 45 years or over.
•
• Because the defect arises in the ovum, both parents are
• normal and the condition is not inherited.
• .

• In contrast, about 4% of Down's patients have the
additional chromosomes 21 genetic material
translocated to another chromosome.

• The translocation is transmitted in a familial pattern
but the parents are normal and the risk of an affected
child is relatively low.

In rare cases of mosaic Down's syndrome the
trisomy arises during early development and the
patients are a mosaic of cells with and without
trisomy 21.

• In this type of Down's syndrome the features are
very variable and intelligence may be normal despite
the typical appearance.

• General features:-

• Class III malocclusion with
hypoplastic maxilla.

• Protrusive, fissured and enlarged
tongue.

• Everted, thick, dry and crusted
lips.

• Oligodontia.
• Delayed eruption of teeth.

• Hypoplastic dental defects and
short roots.

• Low caries activity.

• Gross plaque accumulation.

• Rapidly progressive periodontal
disease.

• Bruxism.

• Cleft palate in a minority.

• Short stature with short limbs.

• Poor muscle tone.

• Generalized susceptibility to infection.

• Cardiac anomalies in 40% .

• Susceptibility to leukaemia.

• Alzheimer-like dementia in later life.

• Macroglossia of either type may produce displacement of teeth
and malocclusion because of the muscles involved and
• The pressure exerted by the tongue on the teeth

5- Cleft tongue
• A completely cleft or
bifid tongue is a rare
• It results from lack of
fusion of the lateral
halves of this organ.

• A partially cleft tongue
is manifested as a deep
groove in the midline of
the dorsal surface

6- Fissured tongue (Scrotal
tongue)
• It is a malformation
manifested clinically by
numerous small furrows or
grooves on the dorsal surface
often radiating out from a
central groove along the
midline of the tongue.

• Is usually asymptomatic
• Although some patients may
complain of mild burning
soreness.

7- Hairy tongue
• is not specifically a developmental
disturbance

• it is characterized by hypertrophy
of the filiform papillae of the
tongue with lack of normal
desquamation and form a thick
matted layer on the dorsal surface

• The color may vary from yellowish
white to brown or even black
depending upon their staining

Median rhomboid glossitis
• This congenital abnormality of
the tongue is due to failure of the
tuberculum impar to retract
before fusion of the lateral halves
of the tongue.

• Clinically
• * An ovoid or rhomboid-
shaped reddish patch on the
dorsal surface of tongue
• *Immediately anterior to the
circumvallate papillae.
• *It is a flat or slightly raised
area and has no filiform papillae.

Geographic tongue (benign
migratory glossitis)
• It consists usually of multiple areas
of desquamation of the filiform
papillae of the tongue in an irregular
circinate pattern.

• The central portion :-sometimes
appears inflamed
• the border:-may be outlined by a
thin yellowish line or band.
• The areas of desquamation remain
for a short time on one location and
then heal appears in another
location.
• It may persist for weeks or months
and then regress spontaneously,
only to recur at a later date.

Lingual thyroid nodule:
• It is an anomalous condition in
which follicles of thyroid tissue
are found in the substance of the
tongue possibly
• Arising from a thyroid anlage
which failed to migrate to its
position.
• Clinically:
• * It appears early in life
chiefly during puberty and
adolescence.
• It appears as a nodular mass in
or near the base of the tongue in
the general vicinity of the
foramen caecum,
• most often at the midline.

Ankyloglossia
• Complete ankyloglossia :-
occurs as a result of fusion
between the tongue and
the floor of the mouth
• Partial anykloglossia or
tongue tie usually
resulting of:-
• ** a short lingual
frenum
• **or one which is
attached too near the tip of
the tongue
• , The patients suffer from
speech difficulties.

Developmental
Disturbances of the
gingivae

Elephantiasis Gingivae
(Congenital Macrogingivae )
• A diffuse fibrous over-growth of the
gingival tissues.
• It is a hereditary condition being
transmitted through a dominant
autosomal gene.
• Clinically:
*young children usually appearing about
the time of eruption of the permanent
incisors. *dense diffuse,
smooth or nodular overgrowth of the
gingival tissues of one or both arches.
*normal or pale color.
• Microscopically: it is similar to any
fibrous hyperplasia. The epithelium may
be thickened with elongated rete
processes, although the bulk of the
tissue is composed of dense fibrous
connective tissue and bundles of
collagen fibers which are coarse.

Developmental
Disturbances of the
salivary glands

Aplasia
•
• **This means complete absence of one or more of the
salivary glands.
•
• **It results from failure of the terminal cells of a developing
gland to differentiate.
•
• **No hereditary basis has been reported.

•
• **The condition is not necessarily associated with other
congenital malformation.

• **If the remaining salivary glands can not compensate the
deficiency in salivary secretion caused by the aplastic gland,
dryness of the mouth, (xerostomia).

Atresia

• A condition in which there is congenital
absence or occlusion of one or more of
the ducts of major salivary glands.

• It may result from degeneration or
failure of canalization of the more
proximal part of the epithelial salivary
gland analage after the distal part has
differentiated into salivary tissue.

Aberrancy

• This is a condition in which normal
secreting salivary gland tissue
develops at an abnormal position (
Ectopic ).
• It has no clinical or pathological
significance apart from the fact that the
aberrant tissue may be the site of
development of a cyst or neoplasms.

Latent bone cyst
• This is also known as developmental lingual mandibular
salivary gland inclusion cyst or depression.

• In this condition, a part of the submandibular, or more rarely
the sublingual gland may develop in bony cavity or depression
in the lingual surface of the body of the mandible, maintaining,
however, its connection with its parent gland.

• The condition is usually discovered ancidentally on
radiographic examination, and appears as an elliptical or
rounded radiolucent area most often situated in the molar
region slightly above the lower border of the mandible, between
it and the inferior alveolar canal.

• Latent bone cyst should be differentiated from traumatic
bone cyst which almost lies above the mandibular canal on the
radiographic picture.

Developmental
Disturbances of the
teeth

Initiation stage
(variation in number)

Anodontia
• 1-Total anodontia :
• **Complete developmental
absence of the teeth.
• **very rare ,mostly it is
associated with ectodermal
dysplasia.
• **It is of genetic origin .
**males are more affected.
**It is due to aplasia of the
dental lamina,
**if the permanent teeth are
only missing this means that
further development has been
stopped after giving the enamel
organ of the milk set.

2- Partial anodontia:- •
• **Not so rare as total anodontia.
• **It means developmental
absence of one or more teeth
have never been developed,
the common to be are maxillary
laterals, lower premolars, and
third mo
• **missing teeth in the arch. may
have developed but failed to
erupt ( detect by radiograph) :-
.(1) cleidocranial dysostosis,
(2) teeth may have been
extracted after or before eruption
as in the case of premolars and
molars.
(3)Also in irradiated jaws, we may
have missing teeth if irradiate.

Additional teeth
• 1- Predeciduous Dentition.
• **Infants occasionally are born
with hornified epithelial
structures without roots which
appear to be erupted teeth on
the gingiva over the crest of the
ridge, which may be easily
removed.
•
**Natal teeth:- which may
erupted by the time of birth.
• **Origin:-
• (1)from an accessory bud of
the dental lamina ahead of the
deciduous bud
• (2)or from the bud of an
accessory dental lamina.

• 2- Postpermanent teeth or tooth ( dentition ).
• Most of them are the result of delayed
eruption of retained or embedded teeth.
• A small number of cases, do appear to
represent examples of a postpermanent or
third dentition,
• They are concidered as multiple unerupted
supernumerary teeth.
• They probably develop from a bud of the
dental lamina beyond the permanent tooth
germ.

3-Supernumerary teeth •
• Are teeth in excess of the normal
complement
• . the pathogenesis:-
• * Black ( 1909 ) suggested that
supernumerary teeth are developed from the
whorls of epithelial cells which are left after
the dental lamina disintegrates.
• *hyperactivity of the dental lamina and
its downward growth from the oral
epithelium.
• *a division of the tooth germ.

• . Mesiodense. This is the common
variety, and it can occur singly or in
pairs between the central incisor teeth.
It is usually rudimentary and peg-
shaped.

•
• well-formed supernumerary tooth found
between the central and lateral incisor,
or between the lateral incisor and
canine. Supernumerary teeth in the
mandibular incisor region are usually
normal in size and form.
• . They are most commonly founded in
the anterior region of the maxilla.
• . It may be retained as an impacted
tooth ,preventing the eruption or proper
placement of the adjacent tooth.

Megadontia & microdontia
• Macrodontia:- Large teeth.
• Microdontia:- Small teeth
• The whole dentition or only one
tooth may be affected.
• There are racial differences in the
size of the teeth.
• Teeth may appear large or small in
relation to the jaw size (False micro or
macrodontia)
• Causes of large and small teeth :
• 1- Hereditary.
• 2- Racial.
• 3- Pituitary. Hyperpituitarism results in
large teeth,
• hypopituitarism results in small
teeth.

Gardner's Syndrome:

• It is characterized by the occurrence of
multiple impacted supernumerary
teeth. This syndrome consists of :

• 1- Multiple polyposis of large intestine,
polyposis coli with a high malignant
potential. The intestinal polyosis in this
• condition are permalignant.

• Early recognition of these oral
features should promot bowel
radiography or endoscopy and
possible prophylactic colectomy ( life -
saving. )

• 2- Osteomas of the bones ( long
bone- skull-jaw )

• 3- Multiple epidermoid or
sebaceous cysts of the skin,
particularly on the scalp and back.

• 4- Desmoid tumors. (Skin tumors)

• 5- Impacted supernumerary and
permanent teeth.
• It is due to a single pleiotropic
gene and has an autosomal
dominant pattern of inheritance,
with complete penetration and
variable expression.

Histo-morpho
differentiation
stag( variation in
size & shape ).

Dilaceration

• An angulation, or
sharp bend or curve, in
the root or crown of a
formed tooth. The
condition is though to
be due to trauma
during the period in
which the tooth is
forming.

Dens in dente
• Dental anomaly which can occur in the
crown or root of a tooth ..
• The condition is, rather, an enamel organ
invagination of variable degree, for which
reason, ( Oehlers, 1957 ) has proposed the
more logical and descriptive name, " dens
invaginatous "
• The coronal type :-enamel organ
invagination during the developmental
period of the tooth, it occur by projection
of that invagination into the dentine papilla.
The result is an enamel-lined central cavity
with a small external opening.
• The radicular type. :-proliferation of the
epithelial cells causing an apical ingrowth
into dentine and the result is a radicular
invagination limited by cementum.
• permanent upper lateral incisors. are the
most affected teeth

Gemination

• ** An abnormally shaped tooth appears
as two teeth joined together into one
tooth.
• ** Partial division of single enamel
organ results in the development of two
conjoined teeth.
• **The two components of such teeth
may be equal size, or one of them may
be distinctly larger than the other
• ** Both components, however, share a
single root canal and have one root.
The union involves enamel, dentine and
cementum.

Fusion
• Fused teeth arise through union of
two normally separated teeth
germs.
• Depending upon the stage of
development of the teeth at time of
the union.
• Fusion may be either complete or
incomplete.
• The dentine is always confluent in
cases of true fusion.
• Also fusion may occur between a
normal tooth and a supernumerary
tooth.

Concrescence

• **It is a form of fusion which occurs
after root formation has been
completed.

• **The teeth are united by cementum
only.

• ** It is thought to arise as a result of
• traumatic injury or crowding of teeth
with resorption of the interdental bone

• ** Concrescence may occur between
more than two teeth,).

Taurodontism
• Are a peculiar dental anomaly in
which the body of the tooth is
enlarged on the expense of the
roots.

• Common anomaly of the second
and third molar, first molars are
rarely involved.

• Hammer ( 1964 ) suggested that
the tourodontism is caused by
failure of Hertwig's epithelial sheath
to invaginated at the proper
horizontal level.

• In tourodontism the pulp chamber
is reached to bifurcated or
trifurcated region.

APPOSITION AND
CALCIFICATION STAGE

• The development of normal enamel occurs
in three stages:
• 1- The formative stage: during
which there is deposition of the organic
matrix.
2-The calcification stage: during
which this matrix is mineralized.

– 3- The maturation stage: during which
crystallites enlarge and mature.

Amelogenesis Imperfecta
Hereditary Enamel Dysplasia (
• three types of amelogenesis imperfecta are
recognized.
• 1- Hypoplastic type: in which there is
defective formation of
• matrix
• 2- The hypocalcification: in which there is
defective
• mineralization of the formed matrix.
• 3- The hypomaturation: in which enamel
crystallites remain
• immature .

( Streeter's syndrome ).

• Hereditary Ectodermal
Dysplasia:
• Absence or very thin patchy
hair.
• Defects in the nails.
• Absence of sweat glands.
• Dry skin, failure to sweat.
• The patient likes cold weather
and in summer likes to sit in a
cold bath.
• There is also depressed nasal
bridge and the alveolar process
is deficient in height.

ENAMEL HYPOPLASIA .
• Developmental disturbances of the structures
of teeth may be hereditary or acquired,
involving enamel , dentine or both.
• I- Hereditary amelogenesis imperfecta.
• II- Environmental (acquired)
amelogenesis imperfecta.

• Environmental hypoplasia
• Defined as an incomplete or defective
formation of organic enamel matrix of teeth.

• In the enviromental ( acquired ) type, the cause
may be a local factor that usually affects
individual teeth, or it may be a general systemic
factor affecting all the teeth undergoing
development at the time of the disturbance.
• 1-Local factors:
• a- Trauma.
• b- Infection.
• c- Irradiation.

• 2- Systemic factors.
• a- Nutritional deficiency (vit. A, D, Cal.
&phosphorous).
• b- Exanthematous fever (Scarlet fever, measeles
& chicken
• Pox).
• c- Infantile gastro-intestinal disturbance.
• d- Congenital syphilis.
• e- Ingestion of chemicals.
• - Fluoride.
• - Tetracyclins.
• f- Birth injuries, premature birth or Rh. haemolytic
disease.
• g- Idiopathic causes.
• - Cleido-cranial dysostosis.
• - Mongolism.
• - Osteopetrosis ( marble bone disease ).

The following criteria are useful in
differentiating hereditary , and
enviromental enamel hypoplasia:-

• 1-Hereditary anomalies usually affect both deciduous and
• permanent dentitions, while enviromental factors result in
• only one dentition, or even single tooth or teeth being
• affected.

• 2- Hereditary anomalies usually affect either enamel or dentine,
• where as enviromental factors affects both enamel dentine.

• 3-Hereditary hypoplasia usually produce diffuse or vertically
• wrinkles or grooves where as enviromental hypoplasia
• appear horizontally grooves.

H.E.HYPOPLASIA H.E.HYPOCALCIFICATION
Nature of defect Quantitative Qualitative

Amount of matrix Deficient Normal

Maturation Normal Defective

Mineralization Normal Deficient

Hardness Normal Decreased

Surface texture Smooth in Rough
unpitted areas

Luster Translucent Opaque

Acid solubility Acid soluble Acid insoluble

X-ray appearance Normal Decreased radioopacity
Radioopacity enamel indistinguishable
from dentine
Microscopic appearance Loss of prismatic structure Prismatic structure
maintained

• Hereditary Enamel hypocalcification:
• Here the amount or thickness of enamel
matrix formed is normal and the defect is
failure in its normal maturation and
mineralization.
• As a result of the failure in mineralization,
the enamel will be soft to the probe and will
lack its surface luster or gloss, having
instead an opaque matt surface.

• Microscopically, the prismatic structure of
enamel is maintained, but a surface layer of
laminated material is initially present, but
becomes quickly worn out through attrition.

• Acquired Enamel Hypoplasia: (Enviromental)
• **Except in cases of endemic flourosis, acquired defects of
enamel are usually confined to the permanent dentition.
• **Metabolic disturbances and infections severe enough to
affect the structure of developing teeth will usually give rise to
abortion when they occur at such an early stage of foetal life as
to affect the developing deciduous teeth.
• **Acquired enamel hypoplasia of the permanent teeth may be
due to either local or systemic factor.

• 1-Local factors:
• a- Trauma:
• ***Traumatic injuries to upper deciduous incisors, especially
the central incisors, being the most exposed teeth, may push
them deeply into their sockets resulting in their roots impinging
upon the developing tooth germs of their permanent
successors. Apart from the possibility of giving rise to
dilacerations, as mentioned above, the trauma may lead to
horizontally oriented hypoplastic defects running between the
previously calcified enamel and that which is yet to be calcified
at the time of trauma.

• b- Infection:
• Periapical infection of a deciduous tooth, usually one of the molars,
may reach the underlying developing tooth germ of one succeeding
premolar and give rise to enamel hypoplasia of that tooth. The
enamel of the affected tooth may be thin, irregular or may be entirely
missing over an area of the crown. Severe infections such as
osteomyelitis of the mandible may also affect the structure of
dentine as well as enamel, or may even completely arrest both
enamel and dentine formation resulting in stunted teeth.

• 2- Systemic Factors:
• Enamel hypoplasia may occur as a result of a number of systemic
factors. The direct cause may either be:-
• (1) Deficiency in mineral supply, or
• (2) Toxic damage to the ameloblasts actively engaged in enamel
formation at the time.
• The hypoplasia usually presents itself clinically as one or more
horizontally oriented rows of pits or depressions on the enamel
surface. The enamel may be nearly normal in color and translucency
or it may be opaque or stained.

• d- Fluorosis or Mottled Enamel:
•
• People who grow up in areas where the water supply contains large
amounts of fluorides, usually 1.5 ppm. or more frequently exhibit
signs of mottling of the enamel of their permanent teeth, the
deciduous dentition being very rarely affected.

• The incidence and severity of mottling increase with the increase in
the fluoride content of the drinking water , and in areas where the
fluoride content reaches or exceeds 4.5 ppm., nearly all the
inhabitants will suffer from some degree of enamel mottling which is
often severe, such teeth, however, show increased resistance to
dental caries.

• Clinically, mottling ranges from being
• (1) very mild where small areas of the enamel surfaces exhibit white
patches that may be slightly opaque or the enamel surface or chalky
or may retain a fine surface gloss, to
• (2) more severe forms where the enamel surfaces shows larger
areas of mottling when the surface will be dull or even pitted, the
enamel may be brittle and easily chipped away, and may even
acquire after eruption a stain ranging from yellowish to brown or
black.

• There is considerable individual variation in
the effects of fluorosis upon different people.
Some patients may suffer from mild mottling
after exposed to relatively low concentrations
of fluorides, while others exposed to higher
concentrations may be completely free or
may only suffer from a mild degree of
mottling.

• Mottling effects may be graded as
follows:

• 1- Very mild: small opaque areas involving
less than 25% of
• the surface area of the tooth.
• 2- Mild : opaque areas involving more than
25% but not
• exceeding 50% of the surface area of the
tooth.
• 3- Moderate: the whole of the enamel surface
may be affected
• with chalky white areas or yellowish or
brown staining. The
• enamel may become easily worn away.
• 4- Severe: the enamel is grossly defective,
opaque, pitted,
• stained brown or black and is brittle

• e- Congenital syphilis:
• Children born to syphilitic mothers show characteristic
abnormalities in the size, shape and structure of some of their
permanent teeth. These changes are so constant that they have
become called the dental stigmata of congenital syphilis. The
deciduous dentition of such children is normal as it develops at such
an early stage of intra-uterine life that abortion results if the
expectant mother contracts the disease at that stage of her
pregnancy.

• The upper first permanent incisors, and the first molars of both jaws
are almost consistently affected in congenital syphilis. Sometimes,
the maxillary lateral incisors or canines may also be affected.

• Congenital syphilis is transmitted to the off spring only by an infected
mother and is not inherited.

• Reported by pathognomonic of the disease is the occurrence of
Hutchinson's triad :-hypoplasia of the incisor and molar teeth, eighth
nerve deafness and interstitial keratitis.

• HUTCHINSON'S TEETH.

• The characteristic upper permanent central
incisors of congenital syphilis are known as
Hutchinson's teeth.
• They are barrel-shaped teeth whose mesial and
distal surfaces converge towards each other in
the incisal half, the mesial and distal incisal
angles are rounded-off especially the mesial,
they are notched in the middle of the the incisal
edge

• MOON'S AND MULBERRY MOLARS:
• The first permanent molars of congenitally
syphilitic patients may be dome-shaped
(Moon's molars ), or their occlusal surfaces
may be rough, pitted exhibiting multiple
irregular tubercles replacing their normal
cuspal pattern (Mulberry molars

• The enamel of such teeth is hypoplastic, or it
may be entirely lacking over certain areas of the
crown surfaces; and the dentine too is often
hypoplastic. It has been shown that the cause
of these defects is perivascular oedema and
infiltration of the developing tooth follicles
causing the ameloblastic layer of cells to
proliferate and bulge into the dentine papilla
causing the described typical deformities.

DENTINOGENSIS IMPERFECTA.
• Hereditary brown opalescent dentine:
• This is a better term than dentinogenesis
imperfecta.
•
• This is due to inherited dominant gene, and
affecting all the teeth of both dentitions. In
most cases 50% of the children are
affected.

• When it occurs together with bone
disorders it is called osteogenesis
imperfecta.

• The teeth are small with bulbous crowns,
constricted neck, short roots are somewhat
translucent on eruption and later become
gradually gray or brown with bluish
reflection from the enamel , the teeth wear
away quickly, disorder is mainly in the
formation of the dentine but the enamel is
often poorly calcified and tends to break
and become lost easily in some cases.

• The dentine at the A.D.J is usually normal but that
lying deeply shows disordered structure with a
diminished number of tubules, poor calcification,
imperfect formation of collagenous matrix and marked
irregular incremental lines.

• The pulp cavity becomes obliterated early and there
may be numerous pulp stones.

• In the dentine the tubules are irregular in size and in
their shape.

• In the deciduous dentition the pulp cavity is not
completely obliterated light like chalk.

• When first erupts it is normal and then suffers from
attrition being soft and poorly calcified, acid insoluble
and the matrix is left after decalcification after
eruption it gets discovered brown and chips easily,
rod pattern is normal, interprismatic substance is
wider and clearly defined, and the transverse
striations are well marked.

• Enamel is not clearly differentiated from dentine
radiographically due to this deficient calcification and
the normal white cap of enamel over the dentine is not
seen.

SHELL TEETH.
• This is a rare variant of dentinogenesis imperfecta transmitted
through the same gene.

• Instead of dentine formation, though defective, continuing till it
almost completely obliterates the pulp chamber as is the case
in dentinogenesis imperfecta, further dentine formation
completely ceases leaving a very large pulp chamber
surrounded by a thin shell of dentine, and a normal layer of
enamel.

• Ground sections show enamel of normal appearance lying on a
very layer of tubular dentine and irregular calcified material.
Decalcified sections show a thin peripheral layer of dentine of
normal appearance, at the deeper parts of which the tubules
become dilated and abruptly disappear.
•
• Deep to this, a thin layer of irregular dentine matrix surrounds a
normal pulp chamber containing coarse collagen fibers and no
odontoblasts.

Anomilies Related to Oral and Para-oral Structures

More Related Content

What's hot (20)

Similar to Anomilies Related to Oral and Para-oral Structures (20)

More from Umm Al-Qura University Faculty of Dentistry (20)

Recently uploaded (20)

Anomilies Related to Oral and Para-oral Structures