Составители:
Рубрика:
72
o The four permanent lower incisor teeth each erupt with three small
cuspettes that resemble a serrated edge. These cusps wear down with
use and the teeth remain with a straight edge.
o The four permanent upper incisors may erupt with three very small
cuspettes. These are much less obvious than those on the lower
incisors. They are also normally worn away to form a straight edge.
• Enamel
o The enamel is a hard white covering over the crown of the tooth.
o It is shaped into cusps, fissures and pits in premolar and molar teeth.
o It is the hardest material in the body and does not have a nerve
supply.
Chipping or damage to enamel only will not be painful.
o It also does not have a blood supply.
This results in a chipped tooth remaining exactly as it is.
The enamel cannot heal or repair as bone or dentine can.
• Dentine
o The dentine is a cream coloured hard material that makes up the bulk
of the tooth.
Страницы
- « первая
- ‹ предыдущая
- …
- 70
- 71
- 72
- 73
- 74
- …
- следующая ›
- последняя »
