What hormones are responsible for bony remodelling ?
PTH, oestrogen, vitamin D3.
What type of defect is osteogenesis imperfect ?
Type 1 collagen defect.
What is the clinical features of osteogenesis imperfecta ?
Weak bones, multiple fractures.
Describe achondroplasia.
Autosomal dominant condition causing poor endochondral ossification resulting in dwarfism.
Describe osteopetrosis.
Lack of osteoclast activity resulting in failure of resorption and marrow obliteration causing increased density of bone and causing it to become brittle.
Describe fibrous dysplasia.
- 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.
If fibrous dysplasia affects the head and neck, what jaw is it most likely to affect ?
Maxilla.
Causing facial asymmetry.
More common subtype - single bone.
What are the oral signs of fibrous dysplasia ?
Intra-oral bony swellings of cortices.
Facial asymmetry.
Unilateral OB.
Describe rarefying osteitis.
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.
Describe sclerosing osteitis.
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.
Describe idiopathic osteosclerosis.
* Aetiology.
* Where it is most commonly found in the mouth.
* Symptoms.
* Does it requried tx ?
- 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.
Describe alveolar osteitis.
‘Dry socket’ - inflammation of the bone due to poor wound (loss of blood clot) healing following extraction of a tooth.
What are the etiological factors of alveolar osteitis ?
Women, contraceptives, smokers, posterior mandibular extractions, previous alveolar osteitis.
What are the symptoms of alveolar osteitis ?
- Constant severe pain.
- Bone sequestra.
- Bad taste/smell.
- +/- pus.
Describe osteomyelitis.
Rare endogenous infection causing exposure of bone from extraction or fracture.
Can be chronic or acute.
What are some causes of bone necrosis ?
Osteomyelitis.
Avascular necrosis (age related or MRONJ).
Irradiation (ORN).
What three medical conditions might be treated using osteoclast inhibitors ?
Osteoporosis, bone metastases, Paget’s.
Describe osteoporosis.
Bone atrophy where resorption exceeds formation i.e. endosteal net bone loss causing quantitive deficiency.
What are some symptoms of osteoporosis ?
Asymptomatic.
Weakened bones.
Antrum enlarged.
What are some aetiological factors for osteoporosis ?
Sex hormone status i.e. menopause.
Age.
Calcium status and physical activity.
Secondary to other systemic disease.
What systemic disease can cause secondary osteoporosis ?
Hyperparathyroidism.
Cushing’s syndrome.
Diabetes mellitus.
Long term steroid use.
What is the etiological factors for rickets/osteomalacia ?
Vit D deficiency i.e. lack of sunlight, diet, malabsorption, renal causes.
Osteoid forms but fails to calcify - qualitative defect.
Describe the epidemiological factors associated with Paget’s bone disease.
Males more common.
>40 years old.
British population.
What is the sign of Paget’s disease from serum biochemistry ?
Raised alkaline phosphate in blood.
