Diseases of the Jaw II Flashcards
What are fibro-osseous lesions?
Lesions where normal bone is replaced by fibrous tissue in which abnormal bone is laid down
Radiographic features of fibro-osseous lesions?
Initially radiolucent bcos of bone loss
Later more mixed radiodensity lesion as the abnormal bone is laid down
Extent of this varies with the lesion, some lesions are almost always radio-opaque or radiolucent
Types of fibro-osseous lesions?
Neoplastic: (Cemento) ossifying fibroma
Developmental: fibrous dysplasia
Reactive: (Cemento) osseous dysplasia
Osteodystrophy
- Ideopathic - paget’s disease
What is an ossifying fibroma?
Benign neoplasm composed of fibrous tissue which forms spicules, islands of cementicles of bone
20-50yrs old, average 35yrs - Children may be affected Females>Males (3:1) Mandible most common site (65%) - Premolar or molar region - May be in craniofacial bones
Ossifying fibroma histology and radiographic appearance>
Lesion has well defined margin and is separated from cortical bone
Early stage
- Well defined, radiolucent, not corticated, root resorption, expansion of mandible
Mature
- Increased amount of bone being laid down
- Cotton wool like
Patient management of ossifying fibroma?
Conservative enucleation
Resection
Low recurrence rate
Fibrous dysplasia features?
Developmental disorder of bone - Mutations in GNAS1, not inherited 25% affect head and neck 15-30yrs old Males = females Painless smooth enlargements/swellings Maxilla most frequent site in H&N Poorly demarcated radiopacity
Histology:
- Fibrous tissue replacing bone (fibroblasts)
- Alteration of normal bone and marrow spaces
- Retraction artefacts around bone (white areas around bone) and the stroma is less cellular than ossifying fibroma
Radiographic appearance of fibrous dysplasia?
Stippled orange peel appearance
Merges with surrounding bone
Clinical variants of fibrous dysplasia?
Monostotic (single bone invovled): • Single skeletal lesions • Ribs and femur most common site • 25% of lesions in head and neck • Age 15-30 (average 25) • Males = females
Polyostotic (multiple bones involved): • Multiple lesions • Head & neck involved in 50% • Age: <15 • 75% in females • May be part of McCune-Albright’s syndrome
Patient management of fibrous dysplasia?
Growth stabilises over time (skeletal maturity)
Debulking and contouring of bone
- Recurrence if during growth phase
- Can reactivate in pregnancy
Surgical removal
Orthodontics and orthognathic surgery
V low risk of malignant transformation
Differences of fibrous dysplasia and ossifying fibroma?
Fibrous dysplasia
- Poorly defined lesion
- No margin
- Males = females
- Often maxilla
Ossifying fibroma
- Well defined lesion
- Clear margin
- Females > Males
- Often mandible
(Cemento)osseous dysplasias features?
A clinicopathological spectrum of reactive lesions
Age 30-50
Often females
Often multiple radiopacities in the tooth bearing areas of the jaws
Composed of irregular trabeculae of woven bone and cementum in fibrous stroma
Classification of osseous dysplasias?
• Focal - Single lesions • Periapical - Multiple lesions at apex of the teeth • Florid - Multiple lesions throughout the jaws
Periapical osseous dysplasia features?
Multiple mixed radiodensity lesions
Florid osseous dysplasia: familial gigantiform cementoma features?
Usually described as a variant of Florid OD
• Appears to be a different entity to Florid OD
• Autosomal dominant inheritance pattern
• M=F
• Found in white patients
What is Paget’s disease?
Rare disorder affecting bones
Bone turnover increased and no longer related to functional demands
Early stages: bone becomes very vascular, may result in heart failure
Later stages: bone becomes sclerotic and shows numerous resting and reversal lines
Clinical features of paget’s disease?
Legs become bowed
Enlargement of the skull causing constriction of foramen: deafness, hats do not fit
Jaws become enlarged: tooth spacing and dentures do not fit
Dental implications of paget’s disease?
Bone sclerotic: difficulty with extractions and prone to infections
Hypercementosis: difficulty with extractions
Bisphosphonates may complicate matters
Increased incidence of osteosarcomas and other bone malignancy
Giant cell lesions of the jaws - what characterises them?
Characterised by replacement of bone by fibrous tissue containing numerous multi-nucleate giant cells (osteoclasts)
Cherubism
Central giant cell granuloma
Hyperparathyroidism
What is cherubism?
Developmental condition
• Autosomal dominant inheritance
• Bilateral expansion of posterior mandible
• May regress after puberty
Histology - vascular multinucleated giant cell lesions
Giant cell lesions of the jaws: features?
Reactive or hyperplastic lesions • Benign but may be locally destructive • Age: 10-30 • 60% in females • Usually mandible • Characterised by osteoclasts
- Giant cell granuloma (central or peripheral)
- Hyperparathyroidism (Brown tumour)
Central giant cell granuloma
Well demarcated radiolucency
Composed of giant cells - osteoclasts
May be destructive - root resorption
Pt management of giant cell lesions of jaws?
Blood biochemistry (serum calcium initially)
Curettage
Resection
20% recurrence rate
Types of hyperparathyroidism?
Primary: parathyroid adenoma (90%)
Secondary: renal failure, malabsorption
Hereditary: autosomal dominant
Radiolucent lesion - demin of sinus outline and inferior border of mandible
Brown tumour identical to central giant cell granuloma
Blood biochemistry of hyperparathyroidism?
Raised serum calcium, phosphate
Parthyroid hormone
Management of hyperparathyroidism?
Surgery
