Dental anomalies Flashcards
What subcategories can dental anomalies be classed into?
Anomalies in :
- Number
- Size
- Form
- Structure
- Eruptio
What anomalies of number can you have?
Extra teeth - supernumeraries
Missing teeth - hypodontia
What are the different types of supernumerary teeth that you can have?
- tuberculate
- conical
- supplemental
- odontoma
What type of dental anomally is this?
Supplemental tooth
resembles a tooth of normal shape/size
A mesiodens is an example of what type of dental anomaly?
A conical supernumerary. It is conical in shape and presents in the midline
What type of dental amonaly is this?
Tuberculate
there is more than one cusp/tubercle
barrel shaped and often palatal to the upper 3s
What type of dental anomaly is this?
Odontoma
complex - posterior mandible
compound - anterior maxilla
What is the incidence of supernumerary teeth in the primary and permanent dentition?
**Primary dentition - **(0.3-0.8%)
Secondary dentition (1-3.5%)
(98% are in the maxilla, 75% of which are mesiodens)
What leads to the formation of supernumerary teeth?
Budding of the dental lamina
they occur sporadially or as a result of a syndrome e.g. cleidocranial dysplasia
How would you manage a supernumerary tooth?
**EXTRACTION **if it was impeding eruption of adjacent teeth, causing displacement, associated pathology or intefering with orthodontic plans
**MONITOR- **roots of adjacent teeth are still forming, symptomless, no pathology
conical teeth tend to erupt and are easily extracted, wheras tuberculate teeth usually dont erupt and require surgical removal
**Define **
hypodontia
oligodontia
anodontia
**Hypodontia - **generally missing teeth
**Oligodontia - ** >6 missing teeth
**Anodontia - **missing all teeth
What is the order of prevalence of missing teeth?
8s> upper 2s> 5s> 1s
Usually the last in the series
What is the aetiology behind hypodontia?
- Obstruction/ disruption of the lamina
- problems with the dental epithelium - failure of initiation or functional abnormaility
- space limitation
- environmental - during pregnancy
- genetic
- syndromes - ectodermal dysplasia, clefts, downs
How can you diagnose hypodontia?
- radiographically
- present as a retained primary tooth
- if teeth fail to erupt
- may present as part of a syndrome
How would you manage hypodontia?
DEPENDS ON THE DEGREE OF HYPODONTIA
aim to restore function, appearance and maintain vertical dimension
- Maintain primary teeth is possible
- orthodontics - space closure/ space creation
- Composite build ups
- autotransplantation
- resorative - implants (when fully grown), bridges, dentures
Which syndromes are associated with hypodontia?
ectodermal dysplasia
cleft lip and palate
down’s syndrome
Albrights disease
Gorlin-goltz syndrome
Hemifacial microsomia
What is ectodermal dysplasia?
A group of syndromes that all have abrnomalities of ectodermal structure. The most common of which is Hypohydrotic Ectodermal dysplasias.
The most common form has an x-linked inheritance
Hair, nails, skin, teeth atc are affected
Define Macrodontia
When a tooth/teeth are larger than normal for that single tooth type
generalised macrodontia may be due to a hormonal imbalance e.g. pituitary gigantism
List the treatment options for macrodontia
- stripping - stip mesial and distal aspects to make it look narrower
- build up of corresponding tooth
- incisal edge notching and labial groove
- extract and provide a prosthesis at a later date - RRB, Implant
Define microdontia
Tooth/teeth smaller than normal for a particular tooth type
females are more likely to be affected than males
Treatment options for microdontia
Build up with composite
veneer
extract and close space - orthodontically, autotransplantation, RRB, implant
What anomalies are there of the form of the tooth?
**CROWN - **Double teeth (germination/fusion)
Dens invaginatus (dens in dente)
dens envaginatus (extra cusp)
accessory cusps
**ROOT - **Taurodontism
What does fusion and germination mean in relation to double teeth?
**Germination - **2 adjoined teeth due to developmental separation of a single tooth germ
**Fusion - **joining of adjacent tooth germs
(if double teeth are present in the primary dentition, there is a 30-50% chance that it will occur in the permanent dentition)
How would you differentiate between germination or fusion of the teeth (a) and what would the treament of the permanent teeth be (b)?
(a) Radiographically
(b) fissure seal the join between the teeth to avoid caries
extract/retain/sugrically divide based on the space/pulp chambers/root canals
What is dens invaginatus?
Dens in dente caused by invagination of the dental papilla
it usually affects the mexiallry incisors and is often bilateral 2x more common in males than females
How you you treat dens invaginatus?
seal the fissures and pits to prevent caries
treat caries with composite
if possible RCT,but may have to extract
How does dens evaginatus present?
As enamel covered by a tubercle on the crown of the tooth. 43% contain pulp
affect mandibular teeth more than the maxialry and usually occur on the occlusal surface of the premolar
Which teeth are usually affected by accessory cusps?
Upper 6s - cusps of Carabelli
**Permanent incisors from the cingulum - **talon cusps
How could you categorise abnormalities of tooth structure?
ENAMEL
DENTINE
CEMENTUM
What are the stages of normal enamel development?
**secretory - **matrix production and initial mineralisation (Defines the form of the tooth)
**maturartion - **increase in mineral content (defines the quality of the tooth)
What is a severe defect of hypomineralised enamel also known as?
HYPOCALCIFICATION
What is a less severe form of hypomineralisation know as?
HYPOMATURATION
What are the local causes on enamel defects?
trauma
infection
idiopathic
irradiation
What are the generalised causes of enamel defects?
Genetic
environmental/chronological/systemic
What is this?
Amelogenesis imperfecta
What condition is this?
Dentinogenesis imperfecta
What is amelogensis imperfecta?
A generalized enamel defect affecting all/predominantly all teeth of the primary and permanent dentitions
What is the mode of inheritance for amelogenesis imperfecta?
Autosomal dominant
autosomal recessive
x-linked
sporadic
What are the different classifications of amelogenesis imperfecta?
Hypoplasia
hypocalcification
hypomaturation
How is the presentation of X-linked AI different to that of autosomal dominant?
Males are more severely and uniformly affected as they only have one x chromosome
females can show vertical ridges or grooves
How would you manage AI?
Depeneds on the severity of the phenotype
severely affected teeth can have cast restorations covering the crown
What genetic disorders can cause generalised defects in the enamel?
Down’s syndrome
Ectodermal dysplasia
epidermolysis bullosa
occulo-dento-osseous dysplasia
What envirmonmental/chronological/systemic causes can give rise to enamel defects?
**Prenatal - **rubella/syphillis
**Neonatal - **premature birth, hypocalcaemia
**Post-natal - **measles, chickenpox, vitamin A/C/D deficiency, chemical agents
What is this?
Fluorosis
This is a developmental disturbance of dental enamel caused by excessive exposure to fluoride during tooth development
What is the cause of fluorosis?
Excessive intake of fluoride during tooth development
drinking water >2ppm
excessive use of fluoride supplements +/- fluoride toothpaste
excessive consumption >0.05mg/kg per day
What problems are associated with fluorosis?
Aesthetics
thermal/osmotic/contact sensitvity
poor OH
Compromised/ reduced occlusion
How can you manage and treat fluorosis?
Do nothing
local composite fillings
composite veneers
procelain veneers
microabrasion
external bleaching
What condition is this?
Molar - incisor hypomineralisation
clinical hypomineralisation of systemic origin of one or more of the first permanent molars and any associated and affected incisors
What are the causes of defects of the dentine?
genetic
environmental
What is dentinogenesis imperfecta?
A genetic disorder of tooth development
it is autosomal dominant and effects both the primary and secondary dentition
It can occur as an isolated condition or with osteogenesis imperfecta (blue sclera)
What are the different cateogories of dentinogenesis imperfecta?
**Type I- **dental manifestation of osteogenesis imperfecta
**Type II - **classic herediatary opalescent dentine
**Type III - **Brandywine isolate opalescent dentine (involves teeth with a shell-like appearance
What condition is this and what are its features?
Dentinogensis imperfecta
Obliteration of the pulp chamber (type I and II)
Short teeth
Bud/Bell shaped crowns with marked cervical constriction
What other genetic conditions can affect the dentine?
**DENTINAL DYSPLASIA - **it is autosomal dominant and affects both dentitions
**Vitamin D - deficient Rickets - ** x-linked condition that affects males with skeletal conditions
Which condition is this?
Tetracyline staining
Children are most suspecptible to tetraclyine staining of the permanent teeth from in utero to the age of 8.
It causes intrinsic staining
Don’t give tetracycline antibiotics to children under the age of 12
What are the two main types of cementum defects?
**Hypercementosis - ** periapical inflammation and mechanical stimulation
**Hypocementosis - ** cleidocranical dysplasia and hypophosphatasia
What condition is this?
Hypercementosis
What condition is this and what caused it?
Turner tooth
Caused by a traumatic injury to a deciduous tooth/ due to a periaplical infection
There is hypoplasia of the enamel and usually involes a single tooth
Give an example of premature tooth eruption
Natal teeth
they are present at birth, the majority of which are mandibular incisors that are not supernumerary
Problems - Mobile due due underdeveloped bone and roots. there is a risk of inhalation
What conditions can natal teeth be linked with?
Ellis-van Creveld syndrome
Soto syndrome
What are neonatal teeth?
Teeth that erupt within the first month of life
What are the management options for neonatal and natal teeth?
Observe
extract
smooth over the incisal edges (this is difficult to do in a child)
What can lead to delayed tooth eruption?
Impacted tooth
traumatic displacement of a tooth germ
dilaceration of permanent tooth germ
presence of supernumeraries/odontomes
Which generalised causes can lead to delayed tooth eruption?
Nutritional deficiency
chromosomal abnormalities - Downs, Turners
Hypothyroidism
Prematurity or low birth weight
What can cause implaction of teeth?
Abnormal position of the tooth germ
supernumerary teeth
cysts
odontogenic tumours
At what age should you palpate for canines in children
9 years
What can lead to premature exfoliation?
Local factors - Trauma, extraction
Systemic factors - hypophosphatasia
cyclic neutropenia
chronic periodontal disease
What local and generalised factors can lead to delayed exfoliation?
Local - infraocclusion
Generalised - cherubism, cleidocranial dysplasia
What is meant by the term infraocclusion?
occlusion in which one or more of the teeth fail to project as far as the normal occlusal plane
how can you categorise infraocclusion?
**Mild - ** occlusal surface is located approximately 1 mm below the expected level of the occlusal plane
**Moderate - **occlusal level approximately level with the contact point of one or both adjacent tooth surfaces
**Severe - ** occlusal level with or below the interproximal gingival tissue or one or both adjacent tooth tissues
Which teeth are most likely to be affected by infraocclusion
Primary molars
Highest incidence of ankylosis ranging rong 1.5 - 9.9%
Ankylosis involves fusion of cementum to the alveolar bone and affects almost all infra-occluded deciduous molars
Which radiological feature suggests ankylosis?
Loss of the lamina dura
What is meant by delayed eruption?
- there is eruption of the contralateral teeth > 6 months previous
- deviation from the normal sequence of eruption
- both upper central incisors are unerrupted although the lower central incisors erupted over a year ago
