Bone Dynamics Flashcards
Is bone a living tissue?
Yes
Bone is a living tissue which responds to the demands of its immediate environment
What are internal factors which effect bone?
Health
Nutrition
Hormones
What are the 4 stages of bone remodelling?
Resting stage
Bone resorption (Howships lacunae) - osteoclasts
Transition
Bone formation - osteoblasts
What is a bone remodelling unit?
A tunnel is bored, bone deposition begins on its walls
Where is the tension zone during alveolar remodelling?
Resorption of bone
Where is the compression zone during alveolar bone remodelling?
Bone resorption area
What is more calcified and dense, cortical or trabecular bone?
Cortical bone
What bone has a higher turnover, trabecular or cortical bone?
Trabecular
Where is trabecular bone mostly found?
Trabecular bone mostly in epiphyses, with some in shaft. High amounts in vertebrae, femoral neck
What does Optical bone provide?
Strength on the outer surfaces and along the shaft
What areas are more prone to fracture?
Femoral neck and vertebrae
In old age
What are the stages in a fracture repair?
Formation of a blood clot
●Replaced by provisional callus (cartilage)
●Callus strengthened by calcium salts
●Osteogenic cells in endosteum and periosteum lay down woven bone – bony callus
●Bony union, woven bone becomes lamellar bone
What does prolonged lack of calcium cause?
Osteoporosis
What does a lack of vitamin D cause?
osteomalacia, rickets, both of which disturb the ability to calcify bone and lead to weak bones (usually also deformed by gravity)
What does a lack of vitamin C cause?
scurvy affects growth plates particularly collagen and proteoglycan production
What is the cutting zone during bone remodelling?
Active osteoclasts followed by capillary loops and dividing cells
What is a closing cone?
Osteoblasts lay down new bone in lamellar to create rings of bone around a central canal
What does this image demonstrate?
- Fracture
- Callus
- Remnants of fracture
