Anatomoy of the Tooth

Crown: part of the tooth covered by enamel.
Root: part of the tooth that anchors the tooth in the alveolus of the mandiable or maxilla.
Neck (Cervix): constricted part of th tooth at the junction of the crown and root.
Enamel: the specialized hard tissue that covers the crown,os both avascular and acellular. It is about 97% mineralized, essentially foosilized once it is formed.
Cervicoenamel line (Junction, CEJ): the line that encircling the crown which is the most rotward extent to enamel.
Dentinonamel junction (DEJ): the boundary between the enamel cap and the underlying dentin.
Dentin: the tissue that forms the core of the tooth.this tissue has no vascular supply but is supported by the vascular system in the pulp and is lined in the inner surface ( the walls of the pulp cavity) by odontoblasts, dentin-producing cells. Dentin undelies the enamel of the crown and encapsulates the pulp cavity, the central soft tissue space within a tooth. Occlusal wear may expose dentin, and beacuse dentin is softer than enamel th resulting expostures are usually occlusally oncave.
Pulp chamber: the expanded part of the pulp cavity at the crown end of the tooth.
Root canal: narrow end of the pulp cavity at the root end of the tooth.
Cementum: bonelike tissue that covers the external surface of tppth roots.
Calculus: calcified desposit commonly found on the sides of the tooth crowns.the origin of the calculus lie with plaque,colonies of microrganism that establish themselves on the teeth.
Pulp: the soft tissue within the pulp chamber. the include nerves and blood vessels.
Apical foramen: the oppening at each root Apex, or tip,through wich nerve fibres and vessels pass from the aveolar region to the pulp cavity.
Cusp: an occluslal projection of the crown. Major cusps of homonid molars are individually named: Protocone,Hypocone,Paracone,Metacone,Protoconid
,Hypoconid,Metaconid,Etoconid,Hypoconulid.
knowledge of these cusps,their reltive sizes and wear, is often valuable in identifying isolated teeth. Cups of the upper jaw end with the suffix -cone whereas the lower jaw end with the suffix -conid. the tips of the cusp is the apex. Ridges that descend from cusp Apices are Crests.
Fissure: a cleft on the occlusal surface between cusps. Fissures divide the cusps into patterns.the most widley aknowledged of these is the Y-5 Pattern, in pattern in which the five lower molar cusps are arranged in a Y Pattern.
*** The primitive mammalian cusp pattern was a triangle of cusps in both upper and lower molars. From this pattern a remarkable variety of forms has arisen through the evolution, ranging from the tall columnar molars of warthogs to the bladelike molars of some carnivors.
In humans, as in most other primates, the mesial (anterior) part of the molar is the Trigon (trigonid in lower molars). The distal (posterior) part of the primate molar, added to the modified original triangle of cusps, is the Talon ( or the Talonid in lower molars).