Non-Carious Disorders of the Teeth Flashcards
Describe the classification of non-carious disorders of the teeth
Acquired - Due to local or systemic factors
Hereditary - Affecting teeth and possibly variety of other tissues
Describe the aetiology of acquired non carious disorders of the teeth
Disturbance in tooth morphogenesis, cytodifferentiation, matrix production, mineralization and eruption of teeth on the basis of the environmental factors
Describe the aetiology of hereditary non carious disorders of the teeth
Disturbance in tooth initiation, morphogenesis, cytodifferentiation, matrix production and mineralization and eruption of teeth on basis of single or multiple genetic defects
What are the general features of acquired non carious disorders of the teeth?
Usually affects the shape colour and size of a small number of teeth
Name 4 local factors for acquired non carious disorders of the teeth
- Trauma
- Infection
- Radiotherapy
- Idiopathic damage
Name 3 systemic factors which cause acquired non carious disorders of the teeth
- Tetracycline staining
- Serious systemic disease or malnutrition
- Fluorosis
Describe the 3 steps of dilacerated incisors
- Trauma displaces crown of developing tooth
- Root development continues at an angle
- Tooth fails to erupt usually with retention of deciduous predecessor
Name 2 things which may cause Turner Teeth
- Local trauma
2. Infection
Describe 3 disorders seen associated with Turner Teeth
- Yellow brown pigmentation of enamel
- Extensive pitting
- Irregularity of crown
What is regional odontodysplasia?
- Ghost teeth
- Presumed local developmental issue
Describe enamel opacities as a non carious disorders of the teeth
- Commonly seen in up to 1 of 3 children
- Random distribution
- Cause unknown but thought to be local
- Histologically hypomineralised
Describe 3 steps of tetracycline staining
- Tetracycline ingested
- Tetracycline becomes incorporated into teeth mineralizing at the time
- Teeth normal when erupt and gradually develop grey colour
Why do teeth only gradually develop a grey colour if they are exposed to tetracycline when mineralizing?
Partial decomposition of the tetracycline incorporated into the tooth structure
Describe how systemic disease may affect teeth when they are developing
- Affects teeth developing at time of insult
- Ameloblasts particularly susceptible as high metabolic requirements
- Usually seen as horizontal band of pitting
How does fluorosis occur?
Ingestion of fluorosis during tooth formation resulting in hypomineralization or hypoplastic enamel
Describe the general features of hereditary non carious disorders of the teeth
Affects number, shape, colour, size and structure of all teeth with a genetic basis therefore, usually have a positive family history
How are hereditary non carious disorders of the teeth broken down into sub categories?
- Teeth only
2. Affection teeth and other tissues
Name 4 examples of tooth only hereditary non carious disorders of the teeth
- Absent / Additional teeth
- Connations
- Dens in Dente
- Amelogenesis and dentinogenesis imperfecta
Name 4 examples of hereditary non carious disorders of the teeth which affect the tooth and other tissues
- Osteogenesis imperfecta
- Cleidocranial dysplasia
- Anhidrotic ectodermal dysplasia
- Down’s Syndrome
What is the difference between hypodontia and oligodontia?
Hypodontia is defined as missing 1-6 teeth excluding third molars and oligodontia is 7+ missing teeth excluding third molars
What can absent teeth be linked to?
Sporadic, familial or due to syndrome eg AED or Down’s
What 4 teeth are most likely to be absent in permanent teeth?
- Third molars
- Upper lateral incisors
- Lower second premolars
- Lower central incisors
Describe the epidemiology of additional teeth
- 1-3% have additional teeth
- Usually in incisor or molar regions
- Predominantly females
- More common for permanent teeth
- Usually in incisor region
Name 2 considerations for additional teeth which remain unerupted
- Often impede eruption or cause resorption
2. Potential for dentigerous cyst to form
What is the difference between supplemental and supernumerary teeth?
Supplemental teeth resemble closely the normal anatomy of a tooth but if not, it is termed supernumerary
What is a mesioden?
Midline maxillary additional teeth
What are 2 examples of multiple teeth?
- Connation
2. Concrescence
What is the difference between connation and concrescence?
Conation is the union of two teeth during development involving enamel, dentine and pulp where concrescence is union of teeth at roots by disposition of cementum
Describe the classification of connations
- Fusion - Union between two initially separate tooth germs
2. Germination - Union by incomplete separation of two teeth developing from single germ
Describe 2 clinical features of connations
- Enlarged crowns with apparent partial separation
2. May cause crowding or delayed eruption of adjacent teeth
Describe the epidemiology of connations
- 0.5-1% population have deciduous tooth connation
- 0.1% population have permanent tooth connation
- Usually affects incisors
- May be bilateral
- May be inherited as autosomal dominant trait
Describe the pathology of concrescence
Usually due to inflammatory or space occupying lesion causing cementum deposition to cause union of two teeth
Describe 2 treatment options of multiple teeth
- Endodontic and restorative procedures
2. Extractions
What is Dens in Dente?
A local disturbance of tooth development characterised by deeply penetrating pit extending into tooth from the crown
Describe the general features of Dens in Dente
- Affects 1-5% population
- Usually involves maxillary lateral incisors
- Often bilateral
Describe 3 clinical features of Dens in Dente
- Tooth crown may be externally normal or distorted to varying degrees
- Invagination arises in crown often extension of cingulum pit
- Base of pit will have thin layer of enamel / dentine
Describe HPC of Dens in Dente
- Present as incidental finding, morphological abnormality or with pulpitic pain
- Often present shortly after tooth eruption
Describe 3 radiographic features of Dens in Dente
- Affected tooth may show intra-coronal radiolucency with or without obvious extension to surface
- May extend to involve root
- May be associated with a periapical radiolucency
Describe the pathology of Dens in Dente
- Deep penetrating pit lined by enamel in continuity with surface
- Distortion of underlying dentine
- Enamel and dentine may be defective
- Active caries may be present
What is amelogenesis imperfecta?
A group of conditions producing inherited congenital defects primarily of enamel formation with or without defects in tooth morphology and/or eruption but without associated systemic abnormalities
Describe 4 general features of amelogenesis imperfecta
- Very rare (1 in 16,000 births)
- Variety of inheritance patterns
- Affects all teeth (deciduous and permanent)
- Variety of clinical appearances
Describe 3 clinical features in hypoplastic amelogenesis imperfecta
- Roughness and discolouration
- Thin enamel
- Normal hardness
Describe 4 clinical features of hypomature amelogenesis imperfecta
- Abnormal thickness
- Opaque or discoloured enamel
- Rapid wear on teeth
- Slightly softer than normal
Describe 4 clinical features of hypocalcified amelogenesis imperfecta
- Rapid wear of teeth
- Abnormal thickness of enamel
- Normal colour
4, Very soft
Describe 3 radiological features of amelogenesis imperfecta
- Thin layer of enamel of normal radiodensity in hypoplastic AI
- Reduced radiodensity of enamel in hypomature and hypocalcified AI
- May have unerupted teeth / delayed eruption of teeth
Why is histology not often used in the diagnosis of amelogenesis imperfecta?
Requires both undecalcified ground sections and decalcified techniques
Give the definition of dentinogenesis imperfecta
A group of conditions producing inherited congenital defects primarily in dentine formation which may or may not be associated with osteogenesis imperfecta
What are 2 main differences between amelogenesis imperfecta and dentinogenesis imperfecta?
- AI affects the enamel where DI affects the dentine
2. AI is not associated with systemic effects and DI may be associated with osteogenesis imperfecta
Describe the general features of dentinogenesis imperfecta
- Rare (1 in 6,000 - 8,000 live births)
- Most commonly associated with OI
- Variety of inheritance patterns
- Range of severity
Describe the potential HPC of a patient with dentinogenesis imperfecta
- Present in childhood
- All teeth similarly affected
- Rapid discolouration or wear of teeth
- Presence of OI
Describe 4 clinical features of dentinogenesis imperfecta
- Amber or blue / grey odour of teeth
- Bulbous crowns
- Easy fracturing of enamel with rapid attrition
- Most have evidence of OI
Describe 3 radiological features of dentinogenesis imperfecta
- Tooth have short roots
- Rapid obliteration of pulp chambers and canals after eruption
- Bone texture may show evidence of OI
Describe 4 pathological features of dentinogenesis imperfecta
- Enamel normal but may be abnormal scalloping at amelodentinal junction
- Mantle dentine normal
- Later formed dentine abnormal with large tubules, entrapped soft tissues and interglobular dentine
- Obliterated pulp cavities
Describe 5 clinical features of cleidocranial dysplasia
- Short stature
- Prominence of frontal, parietal and occipital bones
- Absent or hypoplastic clavicles
- Maxillary hypoplasia with high-arched palate
- Delayed shedding of deciduous teeth and eruption of teeth
Describe 2 features of pathology of cleidocranial dysplasia
- Bone shows coarse trabeculation and thick collagen bundles
- Teeth have thin roots with deficient or absent secondary cellular cementum
Describe the treatment and prognosis of cleidocranial dysplasia
- Combination of surgery to remove deciduous teeth and expose permanent successors and ortho to encourage eruption
- Compatible with long life
What is hypohidrotic ectodermal dysplasia?
An X-linked recessive condition characterised by a developmental failure of ectodermal structures, mainly skin, hair, sweat glands and teeth
Describe 4 general features of hypohidrotic ectodermal dysplasia
- X linked recessive
- Predominantly males affected
- Rare
- Detected in early childhood
Describe 5 clinical features of hypohidrotic ectodermal dysplasia
- Dry smooth skin
- Scant find hair
- Reduced number of sweat glands
- Underdeveloped facial and jaw bones
- Few teeth which are cone shaped
Describe treatment of hypohidrotic ectodermal dysplasia
Prosthetic replacement of missing teeth
What is Down’s Syndrome?
A congenital condition characterised by intellectual disability, a characteristic facies and trisomy of chromosome 21
Describe 4 general features of Down’s Syndrome
- Characteristic facies with prominent epicanthic folds, downwardly slanting palebral fissures and mid facial hypoplasia
- Short stature
- Simian creases in palms
- Special educational needs
Name 2 major presenting complaints from patients with Down’s Syndrome
- Caries
2. Periodontal disease
Describe 4 dental related clinical features of Down’s Syndrome
- Hypodontia of deciduous and permanent dentitions
- Deciduous teeth usually larger than normal
- Periodontal disease may be very active
- Permanent teeth show variety of abnormalities (teeth smaller, incisors oddly shaped and molars may be taurodont)
