Bony Lesions Flashcards
What is the role of osteoblasts and osteoclasts?
Osteoblasts - lay down new bone
Osteoclasts - resorb old bone
What is the role of the parathyroid during bone metabolism?
Parathyroid:
-Increases excretion of phosphate from kidneys which leads to metabolism of calcium and phosphate from bone
-Causes proliferation of osteoclasts
What is a hamartoma?
Benign overgrowth of mature cells/tissues
What is the difference between compound and complex odontomas?
Compound - have identifiable tooth shapes although small
Complex - irregular mass with no similarity to teeth
What is osteomyelitis?
Painful bone injection typically caused by staphylococcus bacteria and will be treated with antibiotics
What is suppuration and how does this effect bone?
(list process in 4 steps)
- Apical infection results in micro-organism infiltration and inflammatory response
- The micro-organisms produce toxins which necrose bone
- The inflammation produces high pressure build-up which causes circulatory death
- Bone dies from ischaemia
What are the 2 contributing factors of bone death?
- Bone death from toxins
- Bone death from ischaemia due to local circulatory collapse
What is chronic focal sclerosis?
What is Garres?
It is an unusual reaction of bone to infection
Garres is another type of osteomyelitis
What is osteoradionecrosis?
Osteoradionecrosis - necrotic bone caused by radiotherapy
-overlying mucosa sloughs away
What is osteonecrosis?
What causes osteonecrosis?
Blood flow to bone is disrupted which causes death of bone tissue - osteoclasts are affected
Treatment with bisphosphonates (MRONJ) can cause osteonecrosis - antibiotics will not help to treat it
What is fibrous dysplasia?
Areas of bone that are replaced by fibrous tissue
What is the difference between monostotic and polyostotic fibrous dysplasia?
Monostotic - one bone involved
Polyostotic - more than one bone involved e.g. Albrights syndrome
What is cherubism?
Is this a form of fibrous dysplasia?
Progressive, painless symmetric swelling of jaw with deciduous teeth shedding early and permanent teeth are often defective, missing and displaced
This is NOT a form of fibrous dysplasia
What is hyperparathyroidism?
Excess osteoclast activity with increased excretion of phosphate and increased reabsorption of calcium
Present as ‘Brown’s Tumours’ - multiple radiolucency’s on radiographs (not a true tumour)
What is Paget’s disease?
How does it affect bones?
How does it present on radiographs?
Paget’s disease - caused by excessive breakdown and formation of bone followed by disorganised bone remodelling
Causes affected bone to weaken and become misshapen and makes patients susceptible to pain, fractures and arthritis in the joints near the affected bone
Presents as ‘woolly’ texture with increased radiolucency’s on radiograph
What is odontogenic myxoma and how does it present on a radiograph?
Odontogenic myxoma - scanty spindle/stellate cells in loose mucoid stroma
Soap bubble appearance on radiograph
Giant cell granuloma - how does this present?
Radiolucent lesion with smooth or ragged boarder which causes displacement of teeth
List 3 primary malignant tumours of bone:
- Osteosarcoma
- Fibrosarcoma
- Chondrosarcoma
Osteosarcoma:
1. How does it present?
2. How does it appear on radiograph?
3. How is it treated?
- Presents with distortion of alveolus, loosening of teeth and bleeding
- Irregular pattern of radiolucency and radiopacity - ‘sunray’ appearance
- Treatment - radical excision and chemotherapy - METASTASISE EARLY IF NOT TREATED
Which oral cancer can also affect bone?
Oral Squamous Cell Carcinoma
What is the term given to metastatic tumours?
How do they present?
How does it appear on radiograph?
Metastatic tumours = Carcinomas
Initially painless with increasing swelling, loosening of teeth and paraesthesia
Ragged radiolucent area in the jaw on radiograph
What 3 features indicate significant findings in terms of a suspected bony lesion?
- Root resorption
- Loosening of teeth
- Gingival bleeding
