Nội dung text Facial Growth & Development of normal occlusion.pdf
FACIAL GROWTH MAYS BASSAM KHANFAR
GROWTH Growth VS Development: - Growth (Anatomical) Increase in size or number of cells. - Development (Physiological) Increase in complexity. Growth at histological level: - Hyperplasia Increase number of cells - Hypertrophy Increase size of cells - Secretion of extracellular material which increase the size of the whole tissue. Types of growth: 1. Soft tissue growth (Interstitial growth). 2. Bony growth: - Intramembranous: A. Sutural growth. B. Surface apposition (surface remodeling). - Endochondral Replacement of cartilage by bone.
DIFFERENT TISSUE SYSTEMS GROW IN DIFFERENT RATES Scammon’s Growth Curve: I. General systems (muscles, bones, viscera) S Shaped Curve Mandible, Maxilla. II. Neural system Grows rapidly after birth until it reach its peak (4 – 5 Y.O) then it will become stable. III. Lymphoid system Grows fast after birth until reach the maximum rate of growth (10 – 12 Y.O), then the growth rate starts declining. IV. Genital system No growth until the 13 years of and then it starts growing rapidly.