BDS4 bone pathology Flashcards
what is systemic hormones of bone remodelling?
- Parathyroid hormone (PTH)
- Vitamin D3
- Oestrogen
- others
what is special tests of bone biochemistry?
- Blood calcium
- Osteoblast activity (bone formation)
*Serum alkaline phosphatase
*Osteocalcin - Osteoclast activity (bone resorption)
*Collagen degradation urine & blood - Parathyroid hormone
- Vitamin D assays (>50 nmol/L adequate)
what is types of torus?
Torus
* Developmental
* Exostosis
Problem with fitting dentures
Types
* Torus palatinus
*Midline of palate
* Torus/tori mandibularis
*Bilateral on lingual aspect of mandible (usually premolar region)
what is this?
Torus mandibularis
what are types of developmental abnormality conditions
Osteogenesis imperfecta
Achondroplasia
Osteopetrosis
Fibrous dysplasia
what are characteristics and clinical features of osteogenesis imperfecta?
- Type 1 collagen defect
- Inheritance varied – 4 main types
- Clinical features
*Weak bones, multiple fractures
*Sometimes associated with dentinogenesis imperfecta
what is characteristics of achondroplasia?
- Autosomal dominant
- Poor endochondral ossification
- Dwarfism
what is characteristics of osteopetrosis
- Lack of osteoclast activity
- Failure of resorption
- Marrow obliteration
what are characteristics of fibrous dysplasia?
Uncommon
* Gene defect
Slow growing, asymptomatic bony swelling
* Bone replaced by fibrous tissue
Active under 20 years
Stops growing after active growth period (usually…)
Serum biochemistry norma
what are clinical phenotypes of fibrous dysplasia?
- Determined by timing of gene mutation
- Monostotic: single bone
*More common
*Maxilla > mandible
*Facial asymmetry - Polyostotic: many bones
- May be syndromic – Albright’s syndrome
*Melanin pigment
*Early puberty
what does fibrous dysplasia look like radiographically?
- Variable appearances
- Margins often blend into adjacent bone
- Bone maintains approximate shape (initially)
- Becomes more radiopaque as lesion matures
what is histology of active fibrous dysplasia?
Fibrous replacement of bone
* Cellular fibrous tissue
* Bone – metaplastic or woven, but
will remodel & increase in density
what is rarefying osteitis?
Localised loss of bone in response to inflammation
* Always occurring secondary to another form of pathology
* If at apex of tooth consider apical periodontitis, periapical granuloma or periapical abscess
what is sclerosis osteitis?
- Localised increase in bone density in response to low-grade inflammation
- Most common around apex of tooth with a necrotic pulp
*Periapical radiopacity, often poorly-defined
*May eventually lead to external root resorption if chronic
what is idiopathic osteosclerosis?
Localised increase in bone density of unknown cause
* a.k.a. dense bone island
* Most common in premolar-molar region of mandible
* Always asymptomatic
* No bony expansion & no effect on adjacent teeth/structures
how to tell difference between idiopathic osteosclerosis and sclerosing osteitis
Carry out sensibility testing on the tooth involved
what is aetiology of bone necrosis?
- Osteomyelitis
*Acute or chronic - Avascular necrosis
*Age-related ischaemia
*Anti-resorptive medication - Irradiation
*Osteoradionecrosis
**Prone to infections
what are osteoclast inhibitors used for?
- osteoporosis
- Paget’s
- bone metastases
what are types of metabolic bone disease?
- Osteoporosis
- Rickets & Osteomalacia
- Hyperparathyroidism
what is osteoporosis and clinical and radiographic features?
- Bone atrophy: resorption exceeds formation
*Endosteal net bone loss
*Quantitative deficiency (bone formed is normal) - Clinical features
*Symptomless
*Weak bone
*Antrum enlarged - Radiographic features
*Loss of normal bone markings
what is aetiology of osteoporosis?
- Sex hormone status
- Age
- Calcium status & physical activity
- Secondary osteoporosis
*Hyperparathyroidism
*Cushing’s syndrome
*Thyrotoxicosis
*Diabetes mellitus
others
what is characteristics of rickets and ostemalacia?
- Vitamin D deficiency
*Lack of sunlight – daylight hours
*Diet
*Malabsorption
*Renal causes - Osteoid forms but fails to calcify
- Rickets
*Poor endochondral bone
*Low calcium
*Raised alkaline phosphatase
what is hyperparathyroidism and types?
- Calcium mobilised from bones
*Generalised osteoporosis
*Osteitis fibrosa cystica (“brown tumours”)
*Metastatic calcification – kidney - Types
*Primary: neoplasia / hyperplasia
*Secondary: hypocalcaemia (e.g. due to vitamin D deficiency)
*Tertiary: hyperplasia as a result of prolonged secondary
what is increased primary hyperparathyroidism?
- mainly posmenopausal women
- 90% parathyroid adenoma (→ increased parathyroid hormone)
*Hypercalcaemia
*Increased bone turnover
what is giant cell lesions of the jaws?
- Peripheral giant cell epulis
- Central giant cell granuloma
*Age 10-25
*Mandible>maxilla
*May be multilocular - Differential diagnosis
*Osteitis fibrosa cystica
*Aneurysmal bone cyst
*Giant cell tumours (very rare) - Central lesions may “burst out”
what is cherubism? histology
- Rare condition
- Autosomal dominant inheritance
- Multicystic/multilocular lesions in multiple quadrants
- Grow before about 7 years & regress after puberty
- Histology: vascular giant cell lesions
what is paget’s disease of bone?
Age > 40, M>F
3% of routine autopsies
Aetiology unknown
* Racial predilection
* Viral?
Monostotic or polyostotic
Serum biochemistry
* Raised alk phos
Clinical
* bone swelling, pain, nerve compression
what is bone patterns and dental changes of paget’s disease of bone?
Variable bone pattern
* Changes as disease progresses
* Osteoporotic / mixed / osteosclerotic
Dental changes
* Loss of lamina dura
* Hypercementosis
* Migration (due to bone enlargement)
what is histology and complications of paget’s bone disease?
Histology
* Active: increased bone turnover
* Osteoclastic & osteoblastic activity
* Will burn out
Complications
* Infection
* Tumour
what are types of bone tymours?
- Osteoma
*Solitary
*Mostly cortical bone
*Slow growing
*If multiple osteomas:
**Consider Gardner syndrome - Osteoblastoma
*Rare
*May be a Giant Osteoid Osteoma
*Often very active growth
what is clinical and histological features of ossifying fibroma?
- Clinical
*Slow growing
*Wide age range
*Mainly mandible
*Radiologically well-defined - Histology
*Cellular fibrous tissue
*Immature bone
*Acellular calcifications
what are types of cementum lesions?
Cementoblastoma
*Neoplasm attached to root
*Histology same as osteoblastoma
Cemento-osseous dysplasias
*Nomenclature problem, probably not neoplastic
*Types:
**Periapical COD
**Focal COD
**Florid COD
*Starts as radiolucency → later calcification
what is osteosarcoma charcateritics?
Age 30’s
*If elderly, likely Paget’s-related
Characteristics
* Mandible > maxilla
* Varied clinical & x-ray presentation
* Local destruction
* Recurrence & metastasis
cementoblastoma
