Dental hard tissues
Box 6.1 Changes in dental enamel with patient age
Water content decreases.
Surface composition changes through ion exchange with oral environment (e.g., fluoridation of enamel surface).
Color darkens, in part through addition of organic matter to the enamel and sclerosis and staining of underlying dentin.
Wear facets occur in areas of heavy function.
Box 6.2 Proteinaceous components of dentin
(mainly Type I collagen with smaller amounts of Type V and Type I trimer collagens)
Noncollagenous dentin-specific proteins
(phosphophoryns, dentin sialoprotein, and dentin matrix protein-1)
Nonspecific proteins associated with mineralized tissues
(e.g., osteocalcin and osteopontin)
|Mineral (hydroxyapatite) content||96||70|