Bone Pathology Flashcards
What hormones are typically involved in bone remodelling?
parathyroid hormone
vitamin D3
oestrogen
special tests that can be done to assess bone biochemistry
blood calcium
osteoblast activity
- serum alkaline phosphate
- osteocalcin
osteoclast activity
- collagen degradation urine and blood
parathyroid hormone
vitamin D assays
osteogenesis imperfecta features
aka “brittle bone disease”
type 1 collagen defect
inheritance varies - 4 main types
- sometimes associated with dentinogenesis imperfecta
achondroplasia features
autosomal dominant
poor endochonral ossification
dwarfism
osteopetrosis features
“marble bone disease”
lack of osteoclast activity
failure of resorption and marrow obliteration
osteoporosis complications
cranial nerve compression. bone fractures, dental impaction etc
fibrous dysplasia features
uncommon
- gene defects
leads to fibrous replacement of bone
- slow growing, asymptomatic bony swelling
active under 20 years
- stop growing after active growth period
serum biochemistry normal
clinical phenotypes of fibrous dysplasia
monostotic
- single bone
- more common
- maxilla > mandible
- facial symmetry
polostotic
- many bones
can be syndromic
- albrights syndrome
what is rarefying osteitis?
localised loss of bone in response to inflammation
what is condensing osteitis?
localised increase in bone density in response to low-grade inflammation
- periapical radiopacity, often poorly defined
- may eventually lead to external root resorption if chronic
idiopathic osetosclerosis
localised increase in bone density of unknown cause
- always asymptomatic
- no bony expansion
- no effect on adjacent teeth or structures
- most common in premoaler-molar region of mandible
Alveolar osteitis risk factors
lower extraction
complex extraction
women
smoking
rinsing too soon
posterior teeth
dry socket signs
severe pain, loss of clot, blood sequestra
osteomyelitis
rare endogenous infection acute or chronic
- suppuration is rare
bone necrosis - aetiology
osteomyelitis
avascular necrosis
-age-related ischaemia
- anti-resorptive medication
irradiation
- ORN - prone to infection
Anti resorptive drugs - how do they work?
inhibit osteoclasts
- used for osteoporosis, Bone metastases, Paget’s
what is osteoporosis?
bone atrophy
- resorption exceeds formation
- quantitative deficiency
osteoporosis clinical features
symtomless (until bone broken)
weak bone
antrum enlarged
radiographic features of osteoporosis
loss of normal bone markings
osteoporosis risk factors
sex hormone status
age
calcium status and physical activity
secondary
- bushings
hyperparathyroidism
diabetes mellitus
Rickets and osteomalacia - cause
vitamin d deficiency
osteoid forms but fails to calcify
Vitamin D deficiency cause
lack of sunlight
diet
malabsorption
renal causes
rickets leads to…
low calcium
poor endochondral bone
raised alkaline phosphate
what is hyperparathyroidism
calcium mobilised from bones
- generalised osteoporosis
- metastatic calcification e.g. kidneys
types of hyperparathyroidism
primary
- neoplasia or hyperplasie
secondary
- hypocalcaemia - vitamin D deficiency
tertiary
- hyperplasia as a result of prolonged secondary
primary hyperparathydrodism prevalence
1:1000
mainly postmenopausal women
F:M 3:1
primary hyperparathyroidism most common aetiology
90% caused due to parathyroid adenoma
- increase parathyroid hormone
- hypercalcaemia
- increased bone turnover
cherubim features
rare condition
autosomal dominant inheritance
grow before about 7 years and regress after puberty
multilocular leisons in multiple quadrants
cherubism histology
vascular giant cell lesions
Paget’s disease of bone - epidemiology
age>40
M>F
3% of routine autopsy
Paget’s disease clinical signs
bony swelling, pain, nerve compression
Paget’s disease aetiology
racal predilection
serum biochemistry
- raised alkaline phosphatase
Paget’s disease bone pattern
variable
changes as disease progresses
- osteoporotic
- mixed
- osteosclerotic
Paget’s disease dental changes
loss of lamina dura
hypercementosis
migration
- due to bone enlargement
Paget’s complications
infection
bone tumours
Paget’s histology
increased bone turnover
osteoclastic and osteoblastic activity
will burn out
what is an osteoma?
a benign tumour of bone
solitary
mostly cortical bone
slow growing
Multiple osteomas may indicate…
Gardner syndrome
- associated with multiple GI polyps
osteoblastoma features
rare
often very active growth
Osteoporosis clinical features
symptomless
weak bone
antrum enlarged
osteoporosis radiographic features
loss of normal bone markings
give examples of cementum lesions
cementoblastoma
cemento-osseous dysplasias
What is a cementoblastoma?
a neoplasm attached to the root
histology same as osteoblastoma
