Enamel and dentine defects diagnosis and tx Flashcards
Enamel defects aetiology
Genetic
Environmental
Idiopathic
Enamel defects presentation
hypoplasia
hypomineralisation (hypocalcified and hypomineralised)
Amelogenesis imperfecta
Clinically and genetically heterogenous group of conditions that affect enamel, occasionally in conjunction with other dental, oral or extra oral tissues
Mutation of genes coding for amelogenesis
Classification of amelogenesis imperfecta
Phenotype:
1. Type 1 (hyperplastic)
2. Type 2 (hypocalcified)
3. Type 3 (hypomature)
4. Type 4 (mixed with taurodontism)
Genetic
1. Autosomal dominant
2. Autosomal recessive
3. X-linked
Hypoplastic general clinical features
Thin enamel
Hard
Shiny
Discoloured yellow through yellow brown
Hypocalcified
Enamel softer
Normal thickness
Discoloured
Teeth affected not usually evenly distributed around the arch, although tends to show bilateral symmetry
Enamel at cervical margin may be more highly mineralised and resistant to wear
Hypomature
Very soft enamel
Defects often limited to the incisal portion of crowns in anterior teeth and occlusal portion in posterior teeth
Mottled with flecks of opaque white ground glass appearance
Maxillary teeth > mandibular teeth
Chronological enamel hypoplasia
Defect is related to the timing of the insult (prenatal/perinatal/postnatal)
Chronologically arranged changes (range from hypomineralised enamel mottling to more severe hypoplastic pitting and degree of disturbance to amelogenesis is generally determined by the severity)
100 aetiological agents report (metabolic disturbances, infections, chemicals and drugs)
Fluorosis
Disturbance of amelogenesis caused by excessive ingestion of fluoride
Vary from white opaque lines to scattered white flecking or a more opaque and confluent dense white chalking that may contain brown discolouration.
Fragmentation of outer layers can lead to pitting or more extensive loss can resemble hypoplastic changes that stain brown
Turner’s hypoplasia
Enamel hypomineralisation
patches of opaque white or yellow/brown discolouration
severe changes less common but an isolated hypoplastic area may be seen
Aetiology: trauma to primary predecessor/infection
Dentine defects classification
Primarily involving dentine:
1. Dentinogenesis imperfecta type II (coronal)
2. Dentine dysplasia type I (radicular dentine dysplasia)
3. Dentine dysplasia type II (coronal dentine dysplasia)
4. Fibrous dysplasia of dentine
Those that form part of a more generalised disorder:
1. Osteogenesis imperfecta
2. Ehlers-Danlos syndrome
3. Vitamin D - resistant rickets/dependent rickets
4. Hypophosphatasia
Dentinogenesis imperfecta type II
Teeth in both dentitions affected
1:8000
Inheritance (autosomal dominant)
Clinical features of dentinogenesis imperfecta type II
Opalescent on transillumination
bluish or brownish in colour
crowns bulbous
roots thin and short
root canals and pulp chamber rapidly obliterated
abnormal adj
Radiographic appearance dentinogenesis imperfecta
short bulbous crowns
marked cervical constriction
short roots
progressive obliteration of pulp chamber
attrition - may lead to loss of vitality and periapical pathology
Dentine dysplasia type I
Colour of teeth - normal to slight bluish
Teeth lost early due to extreme mobility and ease of avulsion with minor trauma
AD inheritance
Radiographically dentine dysplasia type I
Excessively short roots
Blunt roots
Pulp chambers appear small demilunes or obliterated
Root canals absent
Dentine dysplasia type II
Primary teeth resemble those in DI type II
Permanent teeth clinically normal
Radiographically dentine dysplasia type II
Thistle shaped pulp chambers partially occluded by pulp stones
Root canals gradually narrow to point of obliteration
Fibrous dysplasia of dentine
Rare
Teeth normal colour and form
Pulp chambers and root canals represented only by a few radiolucent areas
Osteogenesis imperfecta with DI type I
OI is a group of CT disorders involving inherited abnormalities of type I collagen
Systemic clinical features:
1. Inc bone fragility
2. Blue sclera
3. Lax joints
4. Opalescent health
5. Hearing loss
Dental features:
- primary teeth resemble DI type II
- permanent teeth: (max anterior tooth normal colour and appearance) (mandibular incisor and canine teeth opalescent, discoloured bluish-brown with wear at incisal edges)
Radiographic:
- Variable calcific occlusion of pulp chambers and root canals
- Maxillary anterior teeth may retain pulp chambers and root canals longer than mandibular teeth. This distinguishes type I from type II.
Regional odontodysplasia
rare developmental anomaly
M:F
Affects primary and permanent dentitions
Aetiology? : hereditary/infection/trauma?
CF: segment affected/ delayed eruption/ abscess formation/ malformed crowns
RF: short roots/ wide pulp chambers/ thin, immature enamel
