Transcript Pediatric dentistry

Pediatric dentistry
School of Dentistry
Wuhan University
2006
Hong Qian
Abnormality of tooth
development
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Abnormality of tooth number
congenital absence of teeth
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supernumerary tooth
Abnormality of tooth form
double teeth
geminated teeth fused teeth concrescence of teeth
peg-shaped lateral incisor dens invaginatus dens evaginatus
dilaceration taurodontism
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Abnormality of tooth structure
enamel hypoplasia and hypomineralisation
dentinogenesis imperfecta intrinsic staining of teeth
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Abnormality of tooth eruption
natal and neonatal teeth delayed eruption submerged teeth
ectopic eruption retained teeth
Abnormality of tooth number
Congenital absence of teeth
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Total anodontia: congenital absence of all teeth
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Partial anodontia (hypodontia, oligodontia)
: congenital absence of one or more teeth
Anodontia
Treatment
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Depends on severity of the case
No treatment
Prosthetic replacement
Prognosis: good
Supernumerary tooth
Definition
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Additional to normal series and can be found in
almost any region of dental arch.
Etiology
※ A dichotomy of tooth bud.
※ Local, independent, conditioned hyperactivity of
dental lamina.
※ Heredity. More common in relatives of
affected children than in general population.
Supernumerary tooth
Prevalence
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0.8% of primary dentitions and 2.1% of
permanent dentitions.
Single or multiple, unilateral or bilateral,
erupted or impacted, and in one or both jaws.
Associated with cleft lip and palate,
cleidocranial dysplasia, and Gardner syndrome.
Supernumerary tooth
Conical
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Root formation ahead of or at an
equivalent stage to that of
permanent incisors.
Found high and inverted into palate
or in a horizontal position.
Mostly long axis of tooth is normally
inclined. Can result in rotation or
displacement of permanent incisor,
rarely delays eruption.
Supernumerary tooth
Tuberculate
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More than one cusp or tubercle
Barrel-shaped and may be invaginated
Root formation delayed
Often paired and rarely erupt and frequently
associated with delayed eruption of incisors
Commonly located on palatal aspect of central
incisors
Supernumerary tooth
Supplemental
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Duplication of teeth in normal series and
found at the end of a tooth series.
Most common: permanent maxillary lateral
incisor.
Majority found in primary dentition are of the
supplemental type and seldom remain
impacted.
Supernumerary tooth
Odontoma
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Tumor of odontogenic origin.
Lesion composed of more than one type of
tissue and called a composite odontoma.
Complex composite odontoma: diffuse mass
of dental tissue which is totally disorganized.
Compound composite odontoma:
malformation which bears some superficial
anatomical similarity to normal tooth.
Problems associated with
supernumerary tooth
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Failure of Eruption
Displacement
Crowding
Pathology: dentigerous cyst formation
Alveolar bone grafting
Implant site preparation
Asymptomatic
Indications for supernumerary
removal
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central incisor eruption delayed or inhibited;
evident altered eruption or displacement of central
incisors;
there is associated pathology;
active orthodontic alignment of an incisor in close
proximity to supernumerary is envisaged;
its presence would compromise secondary alveolar
bone grafting in cleft lip and palate patients;
present in bone designated for implant placement;
spontaneous eruption of supernumerary occurred.
Abnormality of tooth form
Double teeth—geminated teeth
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Make two teeth from one enamel organ.
Two completely or incompletely
separated crowns with a single root and
root canal.
Causes: trauma and familial tendency.
Seen in deciduous and permanent
dentition.
Double teeth—fused teeth
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Joining of two tooth germs results in a single
large tooth.
Involve entire length of teeth, or only roots.
Shared or separate root canal.
Causes: trauma and familial tendency.
In deciduous and permanent dentition.
Difficult to differentiate fusion of supernumerary
teeth from gemination.
Double teeth—concrescence of
teeth
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Concrescence is fusion of adjacent
already-formed teeth by cementum.
Take place before or after eruption.
A form of fusion where teeth are united
by cementum only.
Causes: trauma or crowding of teeth.
Peg-shaped lateral incisor
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Reduced mesio-distal diameter and proximal
surfaces converging markedly in incisal direction.
Prevalence: 1% to 2%.
Associated with other dental anomalies like
tooth agenesis, maxillary canine-first premolar
transposition, palataly displacement of maxillary
canine teeth and mandibular lateral incisorcanine transposition.
Peg-shaped lateral incisor
Treatment
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Moving maxillary canines forward and
reshape them with acid etch technique and
bonded composite resin to simulate lateral
incisors.
Restoring missing tooth structure by
increasing size of a peg-shaped lateral
incisor.
Placing full-coverage crown on lateral
incisors.
Dens evaginatus
Definition
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A developmental anomaly in which focal area of crown
projects outward and produces a nodule composed of
pulpal horn and normal layers of enamel and dentin.
The nodule (talon cusp) can result from abnormal
proliferation of enamel epithelium from interior of
stellate reticulum of enamel organ .
Its etiology is unknown.
North American Indian and Asian background
Dens evaginatus
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Problem: fairly soon after tooth eruption this
extra cusp can be ground off during
mastication, resulting in pulp exposure.
Early pulpal necrosis leads incomplete root
development and open apex situation, the
most difficult endodontic cases to apexify.
Surgical treatment is very difficult because of
minimal root length and thin dentinal walls.
Dens evaginatus
Clinical features
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Primarily premolars
Usually bilateral
Conical, tuberculated
projection from central
fissure of occlusal surface
Can interfere with tooth
eruption thus causing tooth
displacement
Dilaceration
Definition
A sharp bend or angulation of root portion of a
tooth.
 Etiology:
Trauma during tooth development or idiopathic
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Dilaceration
Clinical features
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Rare in deciduouos teeth
History of trauma or presence of a cyst, tumor, or odontogenic
hamartoma
Many are nonvital and associated with periapical inflammatory
lesions
Frequently maxillary incisor or mandibular anterior dentition
Dilaceration
Treatment
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Extraction for normal eruption of succedaneous
teeth
Usually no therapy for dilaceration of
permanent teeth
Orthodontic therapy for grossly dilacerated
teeth
Prognosis: good
Abnormality of tooth structure
Enamel hypoplasia and
hypomineralisation
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Local
Developing permanent teeth may be damaged by
trauma or by infection associated with their
predecessors.
Systematic
genetically-transmitted factors, inborn errors of
metabolism, neonatal disturbances, endocrinopathies,
gastrointestinal disease, liver disease and excessive
ingestion of fluoride.
Hereditary
Enamel hypoplasia and
hypomineralisation
Distribution
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Permanent teeth
First molars
-occlusal 1/3
Central incisors and mandibular lateral incisors
-incisal 1/3
Canines
-tips of cusps
Primary teeth
Molars
-cervical-middle 1/3
Canines
-cervical-middle 1/3
Incisors
-cervical 1/3
Enamel hypoplasia
Clinical features
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pits, grooves, lines or larger areas of missing enamel
surface
reduction in enamel thickness
possible occlusal distortion, aesthetic problems,
sensitivity
yelllowish or brownish discoloration
may be localized or present on numerous teeth and all
or part of surfaces of each affected tooth may be
involved
Enamel hypomineralisation
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Poor appearance of anterior teeth
Chipping of enamel, leaving rough surfaces
Attrition of occlusal enamel
Exposure of dentine—tooth sensitivity
Attrition of dentine
Dentinogenesis imperfecta
definition
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A hereditary defect consisting of opalescent
teeth composed of irregularly formed and
undermineralized dentin that obliterates
coronal and root pulpal chambers.
Dentinogenesis imperfecta
Treatment
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composite resin restorations, laminate veneers,
stainless steel crowns on molars, and over
dentures
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Prognosis:
good with early diagnosis
Intrinsic stains
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Intrinsic Stains
Located within tooth anatomy, can be of varied
origin.
May result from pre-eruptive or post-eruptive
causes.
Intrinsic stains
Hereditary conditions
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Hereditary conditions such as porphyria and
phenylketonuria can result in a deposition of
colored materials in teeth.
Other pre-eruptive staining include amelogenesis
imperfecta and dentinogenesis imperfecta.
Tetracycline Staining
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Use of tetracycline during period of tooth formation including last half of in utero development - leads to its
incorporation into tooth structure.
Resulting appearance depends both on intensity of use and
type of tetracycline employed.
Tetracycline can be transferred through placenta and enter
fetal circulation.
Discoloration may be generalized or limited to a specific part
of individual teeth that were developing.
Ingestion of fluoride
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Ingestion of excessive amounts of fluoride during tooth
formation can lead to areas of lighter appearing enamel.
These spots are chalky white and cannot be bleached to
match surrounding enamel. Referred to as 'mottled enamel'.
Whitening does not remove white spots but lightens
background so they are less noticeable. Secondary stains
around these white areas are readily bleached to produce
appearance less noticeable.
Abnormality of tooth eruption
Early eruption-natal tooth and
neonatal tooth (1)
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A.
B.
C.
D.
Natal teeth already present at the time of
birth.
Neonatal teeth erupt during first 30 days
after birth.
Associated Conditions
Cleft Palate
Ellis-van Crevald Syndrome
Hallermann-Streiff Syndrome
Pachyonychia Congenita Syndrome
Natal tooth and neonatal tooth (2)
⊙ Incidence varies from 1:1000 to 1:30 000.
⊙ Either a premature eruption of normal teeth
(up to 95%) or supernumerary (5%).
⊙ Removed only if they are extremely mobile.
⊙ Supernumerary teeth need extraction if
confirmed by radiography.
Natal tooth and neonatal tooth (3)
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Generally develop on lower gum where
central incisors will be.
Little root structure and attached to
margin of gum by soft tissue and often
wobbly.
Not well formed but firm enough, may
cause irritation and trauma to infant's
tongue while he is nursing.
Natal tooth and neonatal tooth:
Home care and treatment
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If not removed, keep them clean by gently
wiping gums and teeth with clean, damp cloth.
Examine infant's gums and tongue frequently to
make sure teeth are not causing injury.
See a dentist if
an infant with natal teeth that develops a sore
tongue or mouth;
other symptoms develop.
Delayed eruption of deciduous or
permanent teeth
Etiology for incisors
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Delayed resorption of a primary incisor
following trauma and death of pulp.
Dilaceration
Supernumerary teeth
Very early loss of a primary tooth, followed by
formation of bone in tooth socket.
Delayed eruption
Etiology for canines and
premolars
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Abnormal eruption path of maxillary permanent
canines.
Impaction against other teeth due to abnormal
angulation or crowding.
Retarded resorption of a primary molar.
Submerged primary molars
Delayed eruption
Etiology for molars
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Impaction against other teeth, especially
affecting third molars.
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Other conditions, such as a dentigerous cyst,
may affect any tooth.
Delayed eruption
Treatment for maxillary permanent
canines (1)
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Extract maxillary primary canines and
surgically expose crowns of permanent
canines in a child aged 10-13 years
if permanent canine might have erupted
normally following extraction.
Delayed eruption
Treatment for maxillary permanent
canines (2)
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Retain maxillary primary canines and extract
permanent canines
If position of a maxillary permanent canine is
unfavourable
If its root development has reached an
advanced stage, prognosis is poor for normal
eruption or for repositioning following extraction
of its predecessor.
Delayed eruption
Treatment for maxillary permanent
canines (3)
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Extract maxillary primary canines and
transplant permanent canines
if position of maxillary permanent canine is
unfavorable for orthodontic alignment.
Ectopic eruption of first permanent
molars
Definition
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Ectopic eruption is a developmental disturbance in
eruption pattern of permanent dentition.
Molar erupts at a mesial angle to normal path of
eruption, results in cessation of eruption and atypical
resorption of neighboring primary molar.
Permanent tooth may get locked in this position
(irreversible) or correct itself without treatment and
erupt into normal position (reversible).
Ectopic eruption
Prevalence
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Prevalence: approximate 4% rate
Almost 60% were reversible.
Mostly seen in maxilla, unilateral or bilateral.
Could not identify significant differences
between different racial groups.
More frequent occurrence in cleft lip and palate
patients
Ectopic eruption
Etiology
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Mesial angle of first permanent molar is clearly
increased. Extraction of second deciduous
molar had no influence on angulation. Cause of
this pronounced mesial inclination could not be
established.
Width of first permanent molar is increased
compared to children with normal eruption.
Size of central incisors cannot be used to
predict ectopic molar eruption.
Ectopic eruption
Clinical implication
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A 3-6 month observation period
if resorption on primary molar is not too severe.
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Cases that self correct usually correct
before 7 years of age.
Ectopic eruption
Treatment
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Treatment goals for irreversible ectopic eruption are
movement of permanent molar distally in order to
regain space and correction of mesial tipping of
permanent molar to allow normal eruption.
Disimpact tooth using soft brass ligature wire if
tooth is impacted against crown rather than root of
primary molar.
Distal slicing of primary molar is not indicated
because it will result in space loss and permanent
molar erupt in tipped position that favor development of
malocclusion.
Retained deciduous tooth
Definition
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Deciduous teeth retained beyond time of
exfoliation are diagnosed as retained
deciduous tooth.
Causes: absence of bud of permanent tooth or
abnormal displacement of bud in embroyonic
life.