Anomalies Flashcards
Which teeth are least likely to be missing?
first permanent molars
upper central incisors
Which teeth are more likely to be missing?
mandibular premolars
maxillary lateral incisors
List down conditions that are associated with hypodontia.
ectodermal dysplasia
down syndrome
cleft palate
hurler’s syndrome
inncontinentia pigmentii
What is hypodontia?
missing teeth
What is a complication that can occur with an upper lateral incisor is missing?
over-eruption of lower canines can be a restorative problem
What are the complications that can arise due to hypodontia?
(5)
abnormal shape/form
spacing
submergence
deep overbite
reduced LFH
What are the treatment options for hypodontia?
overdenture
partial denture
composite
porcelain veneers
fixed prostheses (i.e. implants)
What is the incidence of hyperdontia/supernumerary between males and females?
male 2:1 female
In which arch is supernumerary more common?
hyperdontia
maxilla
Name a condition that has a high frequency of hyperdontia
supernumerary
cleidocranial dysplasia
Name the 4 different types of supernumerary.
- Conical (cone shaped)
- Tuberculate (barrel shaped, has tubercles)
- Supplemental (looks like tooth of normal series)
- Odontome (irregular mass of dental hard tissue, compound or complex)
What is the most common cause of delayed eruption of permanent incisor teeth?
presence of supernumerary teeth
What is gemination?
one tooth splits into 2
double teeth
What is fusion?
double teeth
2 teeth join to form 1
What is the incidence (%) of short root?
2.5% in permanent maxillary incisors
15% of these children also have short roots on the canines and premolars
What are the main types of amelogenesis imperfecta?
(4)
- hypoplastic
- hypocalcified
- hypomaturational
- mixed with taurodontism
What are the environmental causes that can bring about environmental enamel hypoplasia?
(6)
- systemic
- nutritional
- metabolic e.g. Rhesus incompatability, liver disease
- infection e.g. measles
- trauma
- infection of primary tooth
What is the incidence of amelogenesis imperfecta?
1:14,000
What is the aetiology of amelogenesis imperfecta?
It is a hereditary condition that can be autosomal dominant, recessive and x-linked.
How can amelogenesis imperfecta be diagnosed?
- family history
- generally affects both dentitions
- affects all teeth
- tooth size, structure, colour
- radiographs
What is amelogenesis imperfecta of the hypoplastic type?
enamel crystals do not grow to the correct length
What is amelogenesis imperfecta of the hypomineralised type?
crystallites fail to grow in thickness and width
What is amelogenesis imperfecta of the hypomaturational type?
enamel crystals grow incompletely in thickness or width but to normal length with incomplete mineralisation
What are the genes involved/mutated in amelogenesis imperfecta?
genes required for enamel formation
- amelogenin
- enamelin
- kallikrein 4
enamel extracellular matrix molecules
What are the complications of amelogenesis imperfecta?
- sensitivity
- caries susceptibility
- poor aesthetics
- poor oral hygiene
- delayed eruption
- anterior open bite
What is the management for amelogenesis imperfecta?
- preventive therapy
- composite veneers/composite wash
- fissure sealants
- metal onlays
- stainless steel crowns
- orthodontics
List systemic disorders that are associated with enamel defects.
- epidermolysis bullosa
- incontinenta pigmenti
- downs syndrome
- prader-willi
- porphyria
- tuberous sclerosis
- pseudohypoparathyroidism
- hurler’s
What is dentine dysplasia?
- normal crown morphology
- amber radiolucency
- pulpal obliteration
- short constricted roots
What is odontodysplasia?
- localised arrest in tooth development
- thin layers of enamel and dentine
- large pulp chambers
- “ghost teeth”
What are the 3 types of dentinogenesis imperfecta?
Type 1: osteogenesis imperfecta
Type 2: autosomal dominant
Type 3: Brandywine
How can dentinogenesis imperfecta be diagnosed?
- appearance
- family history
- associated osteogenesis imperfecta
- both dentitions affected
- radiograph shows bulbous crowns, obliterated pulps (I & II)
- enamel loss
What is an ocular feature of type I dentinogenesis imperfecta with osteogenesis imperfecta?
blue sclera
What are the complications of dentinogenesis imperfecta?
- aesthetics
- caries susceptibility
- spontaneous abscess
What is the management of dentinogenesis imperfecta?
- prevention
- composite veneers
- overdentures
- removable prostheses
- stainless steel crowns
List systemic disorders that are associated with dentine defects.
- osteogenesis imperfecta
- ehlers-danlos syndrome
- brachio-skeletal genital syndrome
- rickets
- hypophosphatasia
What are the causes of premature exfoliation of teeth?
(6)
- trauma
- following pulpotomy
- hypophosphatasia
- immunological deficiency e.g. cyclic neutropaenia
- chediak-higashi syndrome
- histiocytosis X
What are the causes of delayed exfolation of teeth?
(5)
- infra-occlusion
- ‘double’ primary teeth
- hypodontia
- ectopic permanent successors
- following trauma
Which tooth is most commonly infra-occluded?
lower first primary molar
due to a congenital abscence of premolar tooth
most would then exfoliate normally by age 11-12 years
