Structural abnormalities affecting enamel and dentine Flashcards
What is the most common defect?
Amelogenesis imperfecta
Abnormalities from dental lamina formation stage
Hypodontia
Supernumerary teeth
Double teeth
Odontomes
Odontogenic tumours/keratocyst
Histodifferentiation stage
Regional odonto-dysplasia
Morphodifferentiation (size and shape)
Macrodontia
Microdontia
Dens invaginatus/evaginatus
Talon cusp
Taurodontism
Matrix deposition
Amelogenesis imperfecta
Dentinogenesis imperfecta
MIH
Chronological enamel hypoplasia
Fluorosis
Dentine dysplasia
Eruption and root development
Natal and neonatal teeth
Ectopic eruption
Delayed eruption
Transposition
Impactions
Amelogenesis imperfecta pattern of inheritance
sporadic
almost all teeth are affected to more or less the same extent
developmental condition
genomic in origin
affects the structure and clinical appearance of enamel
associated with morphologic or biochemical changes elsewhere in the body
What are the changes at the formation stage?
Matrix deposition is decreased - thin enamel = quantitative defect
What are the changes at calcification stage?
Matrix mineralisation - quality defect
What are the changes at the maturation stage?
Crystals enlarge/mature - quality defect
What is hypoplasia?
Little enamel
What is hypomineralisation?
Normal enamel but minimal mineralisation
What are the characteristics of hypoplastic enamel?
pitted
hard enamel
reduced amount of enamel
What are the characteristics of hypo mineralised enamel?
white to yellow opacities
soft, porous enamel
poor quality enamel
bonding affected
Diagnostic history questions
FH?
Are all teeth affected in same manner/extent?
Any childhood illnesses during first 3y?
F history - swallowing toothpaste
Maternal issues, birth issues
Pedigree chart
Radiographs
Clin exam
Other issues associated with AI
Accelerated tooth eruption
Impacted perm teeth
Ectopic eruption - second molars
Agenesis of second molars
AOB - 50% in hypoplastic AI
31% in hypomineralised AI
60% in hypocalcified AI
Conditions associated with AI?
Tricho-dento-osseous syndrome - v curly hair in infancy and brittle bones
Cone-rod dystrophy - eventually leads to blindness
Taurodontism - dpt
Nephrocalcinosis
Associated issues with AI
Lifelong tx needed
Aesthetic needs
Ectopic eruptions of impacted teeth
Psychological considerations
Sensitivity
Tooth wear and dysfunction - loss of vertical dimension which needs to be preserved
Bonding issues
Malocclusion
Management of AI
Address pt concerns
Prep patients for long term tx
Tx depends on the type of defect
3m appl of F
Perm restorations when all dentition erupted
Crowns to prevent breakdown and maintain OVD
Anterior teeth management
Microabrasion and bleaching
Composites - 5% NaClO if poor bonding
Posterior teeth management
PMC, onlays, XLA, endo (less common)
Dentogenesis imperfecta
1/6000-8000
Affects dentition exclusively
Associated with systemic conditions
Autosomal dominant pattern - 1 copy of gene needed to cause disorder
Can be associated with osteogenesis imperfecta if type 1 Di
What mutations cause DI 1
Osteo imp association
COLIA1 and COLIA2 gene
What mutations cause D1 2 and 3
DSSP gene
Manifestations of DI 1
Ost Imp
Teeth appear amber and translucent with attrition
Radiographs - short constricted roots and dentine hypertrophy leading to pulpal obliteration
Some teeth show total pulpal obliteration whilst on other the dentine appears normal
MRONJ, bisphosphonates = rare in children
Manifestations of DI 2
2 + 3 appear in people without inherited disorders
type 2 - bulbous crowns and are typical features with marked cervical constriction. normal teeth are never seen
Hearing loss
Manifestations of DI 3
Clin features are variable and resemble those seen in DG 1 and 2 but primary teeth show multiple pulp exposures
Radiographic appearance = shell teeth which appear hollow due to hypertrophy of dentine
Management issues with DI
Aesthetics
Function
Psychological considerations
Management aims remain the same as AI
How to manage primary teeth
SSX
Composite strip crowns
Overdentures
XGA
How to manage permanent teeth
Anteriors - composite
microabrasion/bleaching
overdentures
Posteriors
PFM
Cast gold inlays
Radiographic features of DI
Enamel/dentine radiolucency normal
Bulbous crown
Constricted short roots
Pulp canal obliteration (PCO)
Pinched teeth at cervical margins
Thin, spindly roos
Short ADJ = not defined
Taurodontism, long horned pulp chamber
Bisphosphates in Osteogenesis imperfecta
Inhibit bone resorption
Oral and IV preps
Small blood vessels affected
MRONJ
Limited bone healing
Increased susceptibility to infection
2-8 years
Complete all dental tx in children before prescribing
Post prescribing - non surgical tx if possible and CHX mouthwash pre and post of +/- ABs
