Bone Pathology

Question 1

What hormones are responsible for bony remodelling ?

Answer 1

PTH, oestrogen, vitamin D3.

Question 2

What type of defect is osteogenesis imperfect ?

Answer 2

Type 1 collagen defect.

Question 3

What is the clinical features of osteogenesis imperfecta ?

Answer 3

Weak bones, multiple fractures.

Question 4

Describe achondroplasia.

Answer 4

Autosomal dominant condition causing poor endochondral ossification resulting in dwarfism.

Question 5

Describe osteopetrosis.

Answer 5

Lack of osteoclast activity resulting in failure of resorption and marrow obliteration causing increased density of bone and causing it to become brittle.

Question 6

Describe fibrous dysplasia.

Answer 6

• Gene defect.
• Slow growing, asymptomatic bony swelling.
• Bone is replaced by fibrous tissue.
• Stopping at end of growth period (20s).
• Can affect one bone or multiple.

Question 7

If fibrous dysplasia affects the head and neck, what jaw is it most likely to affect ?

Answer 7

Maxilla.
Causing facial asymmetry.
More common subtype - single bone.

Question 8

What are the oral signs of fibrous dysplasia ?

Answer 8

Intra-oral bony swellings of cortices.
Facial asymmetry.
Unilateral OB.

Question 9

Describe rarefying osteitis.

Answer 9

Localised loss of bone in response to inflammation occurring secondary to other pathology i.e. if at apex of tooth, consider apical periodontitis, PA granuloma or abscess.

Question 10

Describe sclerosing osteitis.

Answer 10

Localised increase in bone density in response to low grade chronic inflammation.

Most commonly surrounding tooth with necrotic pulp and possibly external RR.

Must be treated, an adjacent tooth with have - EPT.

Question 11

Describe idiopathic osteosclerosis.
* Aetiology.
* Where it is most commonly found in the mouth.
* Symptoms.
* Does it requried tx ?

Answer 11

• Localised increase in bone density.
• Unknown aetiology.
• Most common in premolar-molar region of mandible.
• Always asymptomatic.
• Causes no bony expansion.
• Causes no effect on adjacent structures.
• Does not require treatment, adjacent teeth will have + EPT.

Question 12

Describe alveolar osteitis.

Answer 12

‘Dry socket’ - inflammation of the bone due to poor wound (loss of blood clot) healing following extraction of a tooth.

Question 13

What are the etiological factors of alveolar osteitis ?

Answer 13

Women, contraceptives, smokers, posterior mandibular extractions, previous alveolar osteitis.

Question 14

What are the symptoms of alveolar osteitis ?

Answer 14

• Constant severe pain.
• Bone sequestra.
• Bad taste/smell.
• +/- pus.

Question 15

Describe osteomyelitis.

Answer 15

Rare endogenous infection causing exposure of bone from extraction or fracture.
Can be chronic or acute.

Question 16

What are some causes of bone necrosis ?

Answer 16

Osteomyelitis.
Avascular necrosis (age related or MRONJ).
Irradiation (ORN).

Question 17

What three medical conditions might be treated using osteoclast inhibitors ?

Answer 17

Osteoporosis, bone metastases, Paget’s.

Question 18

Describe osteoporosis.

Answer 18

Bone atrophy where resorption exceeds formation i.e. endosteal net bone loss causing quantitive deficiency.

Question 19

What are some symptoms of osteoporosis ?

Answer 19

Asymptomatic.
Weakened bones.
Antrum enlarged.

Question 20

What are some aetiological factors for osteoporosis ?

Answer 20

Sex hormone status i.e. menopause.
Age.
Calcium status and physical activity.
Secondary to other systemic disease.

Question 21

What systemic disease can cause secondary osteoporosis ?

Answer 21

Hyperparathyroidism.
Cushing’s syndrome.
Diabetes mellitus.
Long term steroid use.

Question 22

What is the etiological factors for rickets/osteomalacia ?

Answer 22

Vit D deficiency i.e. lack of sunlight, diet, malabsorption, renal causes.
Osteoid forms but fails to calcify - qualitative defect.

Question 23

Describe the epidemiological factors associated with Paget’s bone disease.

Answer 23

Males more common.
>40 years old.
British population.

Question 24

What is the sign of Paget’s disease from serum biochemistry ?

Answer 24

Raised alkaline phosphate in blood.

Question 25

What is the general physical clinical presentation of Paget’s disease ?

Answer 25

Can be monostotic or polystotic - affecting one bone or more.

• Bone swelling.
• Pain due to nerve compression.
• Increased size of head.
• Deafness.
• Paralysis.

Question 26

What are some clinical dental signs of Paget’s disease ?

Answer 26

Bilateral maxillary enlargement.
Widening of alveolar ridges.
Flattening of hard palate (i.e. loss of palatal vault).
If edentulous, patients may complain of dentures become tight.

Question 27

What is the characteristic radiological bony appearance of Paget’s disease ?

Answer 27

Irregular mosaic trabecular pattern of bone.
Thickening of cortical plate.
Increased radiodensity.
Abnormal bony shape.

Question 28

What are some dental radiographic signs of Paget’s disease ?

Answer 28

Loss of lamina dura.
Hypercementosis (bulging roots).
Migration of teeth due to bone enlargement.

Question 29

Describe the histological appearance of Paget’s disease.

Answer 29

Multinucleated osteoclasts.
Active osteoblasts.
Increased osteoid.
Mosaic appearance to trabecular bone.
Fibrosis of bone marrow.
Proliferation of blood vessels.
Acceleration of calcification.

Question 30

What are the two main complications of Paget’s disease ?

Answer 30

Infection, tumour, osteosarcoma.

Question 31

How would you expect a patient with Paget’s in osteolytic phase to react to extractions ?

Answer 31

Lots of bleeding.

Question 32

How would you expect a patient with Paget’s in osteosclerotic phase to react to extractions ?

Answer 32

Little bleeding, greater risk of MRONJ.

Question 33

Describe an osteoma.

Answer 33

Slow growing solitary bone tumour formed from mostly cortical bone.

Question 34

If a patient presents with multiple osteomas or lumps of the mouth, what condition should you be suspicious of ?

Answer 34

Gardner’s syndrome.

Can result in polyps in colon, high risk of malignant transformation.

Question 35

As well as multiple osteomas, what is another intra-oral sign of Gardner’s syndrome ?

Answer 35

Polyposis coli - multiple freckles and pigmentation in oral mucosa and lips.

Question 36

What age does osteosarcoma most commonly affect ?

Answer 36

30s.

Question 37

Where an elderly patient is diagnosed with osteosarcoma, what condition is it most likely associated to ?

Answer 37

Paget’s disease.

Question 38

In what jaw is osteosarcoma most common in ?

Answer 38

Mandible.

Variable clinical and x-ray presentation and can cause local destruction.

Question 39

What are the histological signs of chronic osteomyelitis ?

Answer 39

Empty lacunae.
Dilated blood vessels.
Neutrophil infiltrate.