ORAL PATH bone pathology Flashcards
how are diagnoses of bone diseases achieved?
a combination of clinical, radiological, histological and biochemical investigations
biochemical: serum levels of calcium, phosphorus and alkaline phosphatase
list the types of giant cell lesions and bone cysts?
central giant cell granuloma
peripheral giant cell granuloma
cherubism
aneurysmal bone cyst
simple bone cyst
describe a central giant cell granuloma?
localised benign (but can be aggressive) lesion
common in the mandible
often asymptomatic
what factor leads to the progression of central giant cell granuloma to peripheral giant cell granuloma?
if the cortical plate perforates = peripheral
histopathology of central giant cell granuloma?
large numbers of multi-nucleate osteoclast like giant cells
set in vascular fibrous stroma
areas of haemorrhage and haemosiderin
what bone lesions are indistinguishable histologically?
cherubism
brown tumour of hyperparathyroidism
giant cell tumour
aneurysmal bone cyst
central giant cell granuloma
what is cherubism?
rare inherited autosomal dominant disease which causes distension of the jaws
describe symptoms of cherubism?
between age 2-4 painless bilateral swelling of the jaws
symmetrical
enlarge until age 7
may regress by adulthood
lesions cause fullness of cheeks and in severe cases maxillary swellings cause eyes to look upward - cherub-like appearance
may have dental anomilies
histopathology of cherubism?
lesions consist mainly of cellular and vascular fibrous tissue - contain varying numbers of multinucleate giant cells
as activity in cherubism decreases, what happens to the lesions?
become progressively more fibrous and numbers of giant cells decrease
list the types of fibro-osseous tumours and dysplasias?
cemento-osseous dysplasia
fibrous dysplasia
juvenile trabecular ossifying fibroma
psammomatoid ossifying fibroma
familial gigantiform cementoma
what are all fibro-osseous lesions histologically characterised by?
replacement of normal bone by cellular fibrous tissue within which islands and trabeculae of metaplastic bone develop
what is cemento-osseous dysplasia?
fibro-osseous lesion occurring in tooth bearing areas of jaws
what is the most common fibro-osseous lesion of jaws?
cemento-osseous dysplasia
cemento-osseous dysplasia symptoms?
often asymptomatic
involved teeth remain vital
what is cemento-osseous dysplasia characterised by?
replacement of normal bone by fibrous tissue and varying amounts of metaplastic bone and cementum-like material
who is predilected to cemento-osseous dysplasia?
middle-aged african/ african-american females
what are the 4 forms of cemento-fibrous dysplasia?
periapical cemento-osseous dysplasia
focal cemento-osseous dysplasia
florid cemento-osseous dysplasia
familial florid cemento-osseous dysplasia
where do you find periapical cemento-osseous dysplasia?
involves apical incisor region of mandible
several adjacent teeth involved
what differs focal from florid cemento-osseous dysplsia?
focal - single tooth
florid - multifocal/ multiquad
treatment for cemento-osseous dysplasia?
surgery only if symptomatic
what is fibrous dysplasia of bone?
fibro-osseous lesion of growing bones
sporadic condition
GNAS1 mutation
what are the 2 types of fibrous dysplasia of bone?
monostotic - involving one bone
polyostotic - involving several bones
what type of fibrous dysplasia is more common?
monostotic
describe symptoms of monostotic fibrous dysplasia?
painless bony swelling, facial asymmetry
usually starts in childhood, arrests in adulthood
where do you find monostotic fibrous dysplasia?
maxilla> mandible
maxillary lesions often involve adjacent bones (craniofacial fibrous dysplasia)
describe monostotic fibrous dysplasia lesions radiographically?
orange-peel/ ground glass effect
what abnormalities are associated with polyostotic fibrous dysplasia?
skin pigmentation and endocrine abonormalities
what syndrome comprises of polyostotic fibrous dysplasia?
albrights syndrome
histopathology of fibrous dysplasia?
irregularly shaped slender trabeculae of woven bone lying in very cellular fibrous tissue
fuses directly with normal bone at edges of lesion
treatment for fibrous dysplasia?
aesthetic surgery
can malignant change occur in fibrous dysplasia?
rare - if it does it is typically osteosarcoma
what are the 3 types of ossifying fibroma?
cemento-ossifying fibroma
juvenile trabecular ossifying fibroma
psammomatoid ossifying fibroma
clinical features of cemento-ossifying fibroma?
occurs in tooth-bearing areas of jaws
slow, painless expansion of jaw
F>M
mandible> maxilla
what is an important features in distinguishing fibrous dysplasia and cemento-ossifying fibroma?
cemento-ossifying fibroma - well demarcated
treatment for cemento-ossifying fibroma?
enucleation and curettage or resection
can recur
clinical features of juvenile trabecular ossifying fibroma?
painless rapid expansion of the jaw
children and adolescents
mandible = maxilla
treatment for juvenile trabecular ossifying fibroma?
enucleation and curettage or resection
can recur
clinical features of psammomatoid ossifying fibroma?
usually painless fast bone expansion
can occur in jaws but most arise in craniofacial bones around paranasal sinuses and orbit
M>F
treatment for psammomatoid ossifying fibroma?
complete excision
can recur
what is familial gigantiform cementoma?
rare form of fibro-osseous lesion of jaws
early onset of fast growing multifocal/ multiquadrant expansive lesions
may be massive with facial deformity
treatment for familial gigantiform cementoma?
surgery - difficult!!
what is segmental odontomaxillary dysplasia?
rare developmental disorder
sporadic
unilateral
what is segmental odontomaxillary dysplasia characterised by?
segmental maxillary and soft tissue enlargement with dento-osseous abnormalities
can be ipsilateral cutaneous manifestations
segmental odontomaxillary dysplasia clinical features?
painless palatal and buccal expansion
dental abnormalities and failure of tooth eruption
list benign maxillofacial bone and cartilage tumours?
osteoma
osteochondroma
osteoblastoma
chrondroblastoma
chrondomyxoid fibroma
desmoplastic fibroma of bone
what is an osteoma?
benign slow growing tumour consisting of well-differentiated mature bone
usually solitary lesion
where do you find osteomas?
mostly in adults M>F
mandible>maxilla
what type of syndrome may you find multiple osteoma lesions?
gardeners syndrome - a rare AD disorder
histopathologically, what are the 2 types of osteomas?
compact type - mass of dense lamellar bone with few marrow spaces
cancellous type - interconnecting trabeculae enclosing fatty or fibrous marrow
treatment for osteomas?
lesions removed if symptomatic or causing problems with fit of denture
what is an osteochondroma?
bony projection with a cap of cartilage which is continuous with underlying bone
rare in maxillofacial bones
treatment for osteochondroma?
complete excision
what is an osteoblastoma?
benign but aggressive bone forming tumour
what is a chondroblastoma?
benign tumour of bone composed of chondroblasts
what is a chondromyxoid fibroma?
benign chondroid tumour
what is a desmoplastic fibroma of bone?
locally aggressive fibroblastic/ myofibroblastic tumour
list malignant maxillofacial bone and cartilage tumours?
osteosarcoma of the jaw
chrondrosarcoma family of tumours
mesenchymal chondrosarcoma
rhabdomyosarcoma with TFCP2 rearrangement
what is osteosarcoma of the jaw?
rare group of malignant bone neoplasms in which the cells produce immature bone
what are chrondrosarcoma family of tumours?
malignant bone neoplasm that produces a cartilaginous matrix - rare
what are mesenchymal chondrosarcomas?
rare high grade biphasic malignant cartilaginous neoplasm
what are rhabdomyosarcoma with TFCP2 rearrangement?
high grade rhabdomyosarcoma with specific gene rearrangement - most occur in bone
list inherited disorders of bone?
osteogenesis imperfecta
osteopetrosis
cleidocranial dysplasia
achondroplasia
osteogenesis imperfecta aetiology?
hereditary : AD and AR and sporadic
what is osteogenesis imperfecta?
impairment of collagen maturation
collagen is component of bone, ligaments, sclerae, dentine and skin
what is the most common type of osteogenesis imperfecta?
type I mild
what are some clinical features of osteogenesis imperfecta?
easily fractured, osteoporotic bone
affected teeth appear as in dentinogenesis imperfecta
malocclusion may be a problem
what is osteopetrosis?
(marble bone disease)
increase in bone density due to failure of normal osteoclast activity and absence of normal modelling resorption
what are the 2 forms of osteopetrosis?
infantile and adult forms
what disorder is common in people with osteopetrosis and why?
anaemia - marrow space deficiency
what is a complication of osteopetrosis? why is this important to dentists?
osteomyelitis - high risk when dental infection present
what is cleidocranial dysplasia?
rare genetic disorder: AD and sporadic
abnormalities of many bones - notable defective formation of clavicles, delayed closure of fontanelles and sometimes retrusion of maxilla
what dental anomalies are common in patients with cleidocranial dysplasia?
delayed eruption of permanent dentition
supernumerary teeth
narrow, high-arched palate
what is achondroplasia?
abnormality in endochondral ossification
head and trunk normal but limbs are excessively short
dental features of achondroplasia?
defective growth at base of skull leads to retrusive maxilla, resulting in severe malocclusion
list metabolic and endocrine disorders of bone?
osteoporosis
hyperparathyroidism
rickets and osteomalacia
acromegaly
describe osteoporosis bones?
excessive bone lose or apposition of bone is reduced
bone is of normal composition but is reduced in quantity
cortex is thinned and more marrow spaces in the cancellous bone associated with thin trabeculae
what type of patients is osteoporosis most common in?
post menopausal women
present in cushings syndrome, thyrotoxicosis, and primary hyperparathyroidism
what medication do people with osteoporosis tend to take?
bisphosphonates
what is hyperparathyroidism?
overproduction of parathormone, PTH
What causes primary hyperparathyroidism?
hyperplasia or adenoma of parathyroids
what causes secondary hyperparathyroidism to develop?
parathormone is produced in response to chronic low levels of calcium - often seen in chronic renal disease
what does a hyperparathyroidism patient present with?
stones - renal calculi
bones - various bone lesions including ‘brown tumour’ of hyperparathyroidism
abdominal groans - duodenal ulcers
how may hyperparathyroidism present in dental patients?
cyst-like swelling of the jaw - has histological features of a giant-cell lesion
what is rickets?
deficiency or resistance to the action of vitamin D
what is rickets adult counterpart?
osteomalacia
dental defects in rickets/ osteomalacia pts?
rarely seen except in severe cases when hypocalcification of dentine and enamel hypoplasia occur
may also be a delay in tooth eruption
what is acromegaly caused by?
prolonged and excessive secretion of growth hormone - due to the anterior pituitary tumour developing after epiphyses have closed
what occurs in acromegaly?
renewed growth of the bones of the jaws, hands and feet with soft tissue overgrowth also
what are the dental features of acromegaly?
enlarged jaw
protrusive jaw
spacing between teeth
thickening of facial soft tissues
list inflammatory diseases of bone?
alveolar osteitis (dry socket)
osteomyelitis
radiation injury and osteoradionecrosis
MRONJ
Pagets disease of bone (osteitis deformans)
when may a patient experience alveolar osteitits?
complication of XLA - particularly in lower molars
how does alveolar osteitis occur?
failure of blood clot to form or dislodgment or breakdown of clot
bone socket becomes infected and necrotic
how is alveolar osteitis localised to the walls of the socket?
inflammatory reaction in the adjacent marrow
if alveolar osteitis wasnt localised to the socket, what would occur?
osteomyelitis
what is osteomyelitis?
spectrum of inflammatory and reactive changes in bone and periosteum
typically in mandible of adults
what are the different forms of osteomyelitis?
acute and chronic suppurative
non-suppurative and sclerotic forms
what factors change the severity of osteomyelitis?
nature and severity or the irritant
host defences
local and systemic predisposing factors
describe radiation injury and osteoradionecrosis?
radiation affects the vascularity of bone
the non vital bone is very susceptible to infection and trauma
infection can spread rapidly through irradiated bone, resulting in osteomyelitis and painful necrosis of bone
why is ORN serious in the mandible?
its end artery supply - ID artery or its branches become thrombosed
what drugs can cause MRONJ?
bisphosphonates
anti-angiogenic drugs
bisphosphonate mode of action?
inhibit osteoclasts
anti-angiogenic drug mode of action?
restrict vascularisation (of tumours)
what disease are bisphosphonates used for?
some cancers
pagets disease
osteoporosis
define MRONJ?
exposed bone, or bone that can be probed through an intraoral or extraoral fistula, in the maxillofacial region that has persisted for more than 8 weeks in patients
with a history of tx with anti-resorptive/ anti-angiogenic drugs
and where there has been no history of radiation therapy to the jaw and no obvious metastatic disease to the jaws
what are risk factors for MRONJ?
high dose
IV administration
MRONJ symptoms?
delayed healing following XLA and other oral surgery
pain
soft tissue infection and swelling
numbness
paraesthesia
exposed bone
histological features of MRONJ?
fragments of non vital bone often with prominent bacterial colonisation
what is pagets disease of bone (osteitis deformans)?
a form of osteodystrophy characterised by disorganised formation and remodelling of bone unrelated to functional requirements
what does pagets disease affect?
single or multiple bones
sacrum, spine, feroma and pelvis most common
maxilla more common that mandible
what happens to the affected bones in Pagets disease?
affected bones are thickened but weaker and pathological fractures occur
progressive enlargement of skull and facial bones - hats dont fit, dentures dont fit
narrowing of foramina - cranial nerve deficits
dental features of pagets disease?
in dentate, derangement of occlusion and spacing of the teeth can occur
hypercementosis and akylosis of teeth - xla difficulty
osteosarcoma - rare complication
giant cell tumours may arise in bones
what are the 3 progressive and overlapping phases of Pagets disease?
- initial predominately osteolytic phase
- active stage of mixed osteolysis and osteogenesis
- predominately osteoblastic or sclerotic phase
what is the main histopathological feature of pagets disease?
(varies with phase)
- irregular pattern of reversal lines
- many osteoblasts and osteoclasts
- fibrosis of marrow spaces and increased vascularity
‘mosaic’ pattern in the bone due to turnover
describe early stage of pagets disease?
more resorption than osteblastic activity
describe late stage of pagets disease?
bones are thick, cortex and medulla are obliterated and the whole bone is spongy in texture
treatment for pagets disease?
calcitonin
bisphosphonates
what are exostoses?
localised bony protuberances - non-neoplastic
aetiology of exostosis?
developmental
chronic trauma
what is a torus?
an exostosis which occurs at a characteristic site, either in midline of palate or lingual surface of mandible
usually premolar region above the mylohyoid line
what type of bone makes up exostosis?
may be entirely dense cortical bone
or
cancellous bone with a shell of cortical bone
what are the most common primary tumours which metastasise to bone?
jaws
breast
bronchus
prostate
thyroid
kidney
what are jaw metastases indicative of?
life-threatening disease
symptoms of jaw metastases?
jaw pain, swelling and paraesthesia/ anaesthesia
what is the radiographic appearance of jaw metastases?
moth-eaten appearance
where are the most common oral sites for metastases?
oral mucosa of the gingiva
alveolar mucosa
tongue
