4. Clinical bone morphology Flashcards
1
Q
Two types of bone formation
A
- Intramembranous
- Endochondrial(Cartilage precursor)
2
Q
Bone definition
A
- Specialised connective tissue
- Mineralised organic matrix, collagenous and non collagenous proteins
- Main component hydroxyapatite
3
Q
Bone cells
A
- Osteoblasts
- Osteoclasts
4
Q
Osteoblasts
A
- Primary bone forming cells
- Synthesise extracellular matrix components and their mineralisation
- Differentiate into bone lining cells:osteocytes
5
Q
Osteoclasts
A
Bone remodelling and repair
6
Q
Change in the bone structure
A
Modelling
7
Q
Change in mineralised bone without change in structure
A
Remodelling
8
Q
Importance of remodelling
A
- Enables substitution of primary woven bone with lamellar bone
- Important when new bone is formed and old bone replaced with new
9
Q
A
10
Q
Bone remodelling cycle
A
- Preosteoclasts recruited to site of resorption
- Differentiate into active osteoclasts and form resorption pits
- Replaced w/ transient mononuclear cells following resoption period
- Preosteoblasts recruited and differentiate into matrix secreting cells and form bone
- Some osteoblasts entrapped in matrix become osteocytes
11
Q
Factors that can affect bone formation and healing
A
- Osteoporosis
- Diabetes Mellitus
12
Q
Osteoporosis
A
- Systemic skeletal disease-> Low bone mass and weakening of structure
- Reduced mineral content, altered non-collagenous proteins
- Increased fracture rate and fragility
13
Q
Diabetes Mellitus
A
- Systemic disease characterised by high sugar levels over prolonged period of time
- Types I-III
14
Q
Type I diabetes
A
- Damage to beta cells in pancreas
- Insufficient insulin production
15
Q
Type II diabetes
A
- Resistance to insulin
- Failure to produce additional insulin to compensate
16
Q
Type III diabetes
A
- Gestational-> Preganant women develop high blood sugar levels
- Altered endochondrial bone growth and remodelling
17
Q
Healing of injured tissue that leads to the formation of tissue that differs in morphology or function to the original
A
Repair
18
Q
Healing that leads to the complete restoration of morphology and function
A
Regeneration
19
Q
Factors that interfere with bone healing
A
- Failure of vessels to proliferate into wound
- Improper stabalisation of the coagulum and granulation tissue in defect
- Ingrowth of non osseous tissue
- Bacterial contamination
20
Q
4 phases of healing of a wound
A
- Blood clot
- Wound cleansing
- Tissue formation
- Tissue modelling and remodelling
21
Q
Classifications of bone by
A
- Misch
- Lekholm and Zarb
22
Q
Misch bone classification
A
- D1- Dense cortical bone
- D2-Homogenous, dense cortical bone on crest and trabecular bone within
- D3- Thin cortical bone on crest and fine trabecular bone within
- D4- Fine trabecular bone
23
Q
Lekholm and Zarb classification
A
- Type I: Homogenous cortical bone
- Type II: Thick cortical bone with marrow cavity
- Type III: Thin cortical bone with dense trabecular bone
- Type IV: Very thin cortical bone with low density trabecular bone
