Growth and Facial Development Flashcards
bone develop is
genetic
soft tissue is
adapt
Endochodral
growth
Replacement of the cartilage matrix by an osseous matrix
long bones
Indirect growth (2)
- Long bones growth pattern
- Involves growth centers or growth plates
genetically programmed
mechanical stress (pressure/tension have no effect)
highly organized
Growth plates or centers (2)
• Where the cartilage matrix is replaced by immature bone • Genetically programmed
Why is this important to us in dentistry?
Cartilaginous growth: Cranial base =
Chondrocranium
INTRAMEMBRANOUS BONE GROWTH ( very important in
dentistry) (3)
• Replacement of connective tissue with bony
tissue
• Irregular bones. ( face, skull, mandible
clavicles)
• Intramembranous growth will result in
displacement of other structures in space
Intramembranous ossification
• The bone formation occurs directly in a
vascularized mesenchyme.
Resorption-Apposition:
New bone forms on the external aspect of the
bone while bone is resorbed on the internal
aspect
The ratio is not always proportional as some
structures must increase in size during growth
V principle of Enlow (2)
• A bony structure will be displaced during growth. • In order to preserve the shape, parts of the bone will receive new bone and parts will resorb.
Placing a V on a growing
osseous structure will
determine the
direction of
growth
• The V is placed on the growth surface. Apposition surfaces are in the --- of the V while resorbing surfaces are located --- the V
center
outside
Growth Mechanisms of the cranio-facial structures (2)
- Intramembranous (direct)
* Displacement of bone in space by resorption/apposition
Drift principle:
allows volume increase and
displacement in space while maintaining the
proper shape
(• Resorption apposition )
