diseases of bones of the jaw Flashcards
what 3 broad groups can bone diseases be divided into?
describe and give examples
- lesions of the jaw bones as part of a systemic bone disease
- most / or all bones affected
- e.g. osteogenesis imperfecta
- localised bone disease occuring in the jaws
- may affected almost any bone, including the jaws
- e.g. osteomyelitis
- lesions occuring only in the jaw bones
- e.g. dental cyst, ameloblastoma
Bone diseases can also be divided into groups depending on aetiology, what are the groups?
- developmental
- inflammatory
- cystic
- metabolic
- disorders of growth
give examples of developmental bone diseases
- torus palatainus
- torua mandibularis
- cleido-cranial dysostosis
- osteopetrosis
- osteogenesis imperfecta
- fibroud dysplasia
- monostotic
- poly stotis
- albright’s syndrome
- condylar hyperplasia
give examples of inflammatory bone diseases
- fracture
- healing extraction socket
- dry socket
- chronic periodontal disease
- osteomyelitis
- actinomycosis
- enostosis
- syphilis
- osteoradionecrosis
- increasingly common in patients treated with radiotherapy for head and neck cancer
give examples of cystic bone diseases
- odontogenic cysts
- developmental
- inflammatory
- non-odontogenic cysts
give examples of metabolic bone diseases
- vitamin deficiency
- vitamin D - rickets and ostemalacia
- vitamin C - scurvy
- endocrine
- acromegaly
- hyperparathyroidism
- steroid drug therapy
- osteoporosis
- functional atrophy - alveolar bone resorption following tooth extraction
- paaget’s disease
give examples of disorders of growth bone diseases
- dysplasia
- giant cell granuloma
- fibrous dysplasia
- neoplasia
- benign - osteoma, chondroma
- malignant primary bone tumours - osteosarcoma
- malignant bone marrow tumours - multiple myeloma, malignant lymphoma
- malignant secondary bone tumours - e.g. from primary breast, prostate and bronchus carcinoma
- odontogenic tumours
what is torus palatinus?
cause?
symptoms?
treatment?
- slow growing, sessile exostosis in the midline of the vault of the palate
- consists of normal lamellar bone
- cortical bone on the surface and lamellar bone in the centre
- strong genetic factor - simple autosomal dominance
- F:M 2:1
- symptomless - usually flat but may be lobular if large
- overlying mucosa may become ulcerated by trauma
- treatment:
- usually requires none but may be removed if it interferes with insertion of denture

what is this?
describe the symptoms you would expect and treatment

torus palatinus
- symptoms :
- symptomless
- treamtent :
- usually requires no treatment but may be removed if it interferes with insertion of denture
what is torus mandiularis?
cause?
symptoms?
treatment?
- exostosis on the lingual aspect of the mandible in the premolar region
- broad base with smooth or lobular surface
- consists of lamellar bone
- cortical bone on the surface and lamellar bone in the centre
- genetic basis
- autosomal dominance with 100% penetrance in females, 70% in males
- bilateral in 80% of cases
- no treatment but may be removed if interferes with insertion of denture

what is this?
symptoms expected?
treatment?

torus mandibularis
- no symptoms
- treatment not required unless interferes with denture insertion
aetiology of osteogenesis imperfecta
hereditary disease
- autosomal dominant most common but recessive forms and spontaneous cases occur
- heterogenous group of related disorders characteristed by defects in type I collagen synthesis
clinical features of osteogenesis imperfecta
- generalised osteoporosis with slender bones
- tendency for the bones to fracture on slight provocation
- slender long bones have narrow, poorly formed cortices composed of immature woven bone
- thin skull - may be wormian bones in the skull
- jaws rarely affected
- sclera may appear blue
- deafness due to distortion of ossicles
- joint hypermobility with lax ligaments
- translucent skin
- heart valve defects
what oral manifestations are associated with osteogenesis imperfecta
- often associated with dentinogenesis imperfecta
- esp. primary dentition
- increased tendency to class II occlusion and impactions of molar teeth
What is diagnosis? Why?

typical presentation of dentinogenesis imperfecta
- brown dentine shown through translucent enamel
- enamel has poor attachment
- defects at dentinal junction
- dentine exposed and slowly worn away
- on radiograph - short roots
what is osteopetrosis?
cause?
- excessive density of all bones
- with obliteration of marrow cavities and development of secondary anaemia
- defect in osteoclastic activity leading to failure of bone remodelling
- excessive formation of mechanically weak bone
- fractures common
- autosomal recessive form severe and progressive - usually death before puberty
- autosomal dominant less severe
what can be seen on a radiograph of someone with osteopetrosis
- bones very dense
- increased thickness and dentistry of lamina dura of tooth sockets

what is cleidocranial dysplasia (cleidocranial dysostosis)?
abnormalities of many bones - particularly skull, jaws and clavicle
- widened cranium
- fontanels and sutures remain open
- skull appears flat
- prominent frontal, parietal and occipital bones
- partial or complete abscence of clavicles
- super numerary and unerupted teeth
describe the steps of a tooth socket healing
- socket fills with extravasated blood which clots
- blood clot is organised to form granulation tissue
- macrophages begin to remove clot at periphery
- fibroblasts in remnants of PDL divide and migrate into clot
- endothelial cells in remnents of PDL divide and produce new thin walled vessels
- osteoclast resorption of crestal bone and spicules of bone detacted during extraction
- gingival epithelial proliferation and migration across defect
- migration between bloot clot and granulation tissue
- osteoblasts appear in granulation tissue at base of socket
- produce unmineralised osteoid
- granulation tissue is replaced by woven bone
- remodelling of woven bone and removal of lamina dura of tooth socket
- radiologically socket usually obliterated 20-30 weeks after extraction
at what times after extraction do the steps of tooth socket healing occur?

when is a patient with dry socket expected to present?
Either
- Immediately after LA has worn off
- Same day as tooth extraction or day after
- Blood clot has failed to form
- 4-6 days after extraction
- Blood clot has disintegrated prematurely before granulation tissue can form on the surface of the tooth socket
in what cases is dry socket more common?
- more in
- molar teeth than anteriors
- mandible than maxilla
- LA than GA
- difficult extraction than simple extraction
- most commin with lower third molar extraction
how does dry socket occur?
aka alveolar osteitis
- localised inflammation of bone following either failure of blood clot to form or premature loss of disintegration of clot
- loss of clot exposes alveolar bone to saliva, food debris and bacteria
- bone becomes necrotic with inflammation in adjacent bone
- healing slow, dead bone separated by osteoclasts, granulation tissue extends from surrounding bone
what are the types of osteomyelitis?
- suppurative osteomyelitis
- chronic sclerosing osteomyelitis
- special
- they are uncommon in the jaws









