Lecture 25 Flashcards
(22 cards)
What supports bone mass?
Sex steroids
What is the range of peak bone mass age?
30 - 40
Which hormones stimulate osteoblasts, and what is the effect of this?
Testosterone and Estrogen
- Increase bone mineralisation
What is the range of peak sex steroids age?
15 - 45
Which hormones inhibit osteoblasts, and what is the effect of this?
Testosterone and Estrogen
- Decrease bone resorption
What is Testosterone converted to?
Aromatase, which is then made into Estrogen
What is Osteoporosis?
Abnormal and accelerated loss of bony tissue resulting in brittle porous bones
What is the impact of Bisphosphonates?
Inhibit osteoclasts by:
- Reducing ruffled border formation
- Reducing adhesion to bone surfaces
- Reducing acid secretion
- Reducing osteoclast progenitor development and recruitment
- Increasing osteoclast apoptosis
What is the relevance of Bisphosphonates in Dentistry?
Can cause osteonecrosis of the jaw
- Exposure of the jaw through the gums
When is Rickets diagnosed usually?
3 - 8 months
What is Rickets caused from?
Usually from lack of Vitamin D
What is Osteomalacia?
Abnormal bone formation, making bones soft
What is Osteomalacia caused from?
Usually from lack of Vitamin D in adults
- Celiac disease
- Kidney/liver dysfunction
- Antiepileptics
What is Paget’s disease
Disrupted bone recycling so, over time, bones become fragile and misshapen
What is the most serve gene mutation in Paget’s disease?
Sequestosome 1 (SQSTM1)
- A scaffold protein in the RANK- nuclear factor κB (NFκB) signalling pathway
What is the end point of the SQSTM1 gene mutation?
Increased bone reabsorption
What is Primary Hyperparathyroidism?
Enlargement of parathyroid gland
- Causes parathyroid
hormone overproduction, increasing calcium levels
What is the result of Secondary Hyperparathyroidism?
Increases PTH secretion to try to maintain plasma calcium levels
What is the mineral content percentage of Enamel?
96% (Hydroxyapatite)
What is the mineral content percentage of Dentine?
70%
What is the mineral content percentage of Cementum?
65%
What is the impact of low calcium in adults?
Increasing the risk of tooth loss on alveolar bone
