Geometric Figures of Crown and Comparative Anatomy of Lower Animals

Mesial, distal, labial, lingual, incisal

Anterior teeth aspects

Mesial, distal, buccal, lingual, occlusal

Posterior teeth aspects

Trapezoidal, Triangular, Rhomboidal

Geometric firgures/crown

The incisal portion of the crown is longer than the cervical portion, and the crown tapers toward the cervical line.

Describe the shape of the anterior/posterior teeth in trapezoidal shape.

The occlusal portion of the crown is longer than the cervical portion, and the crown tapers down toward the occlusal.

Describe the shape of the teeth in trapezoidal shape in mesial and distal aspect.

From the labial/lingual view, the crown tapers towards the cervical and the mesial/distal view, the crown tapers down to the occlusal aspect.

How do the trapezoidal crown outlines of the teeth differed when viewed form the labial/lingual aspect to the mesial/distal aspect?

Anterior and posterior, mesial and distal

Which aspect of the tooth forms the shape of the triangular shape?

Rhomboidal Shape

Seen in mandibular posterior teeth (molar).

Crown tilted lingually

Describe the rhomboidal shape of the mandibular posterior teeth.

Haplodont Stage

Simplest form of tooth, the single cone with spacing, which usually includes many teeth in both jaws that limit jaw movement. There is no occlusion, and mostly used for prehension and combat. An example is a crocodile.

Triconodont Stage

Three cusps at the development of the posterior teeth. The largest in the center is original cusp, with a smaller cusp located anteriorly and another posteriorly.

Tritubercular Stage

Lower molars develop into triangular arrangement of cusp. Triconodont developed that allows tearing and shearing of food, and supports carnivorous diet. Examples are cats and dogs which are carnivores.

Quadritubercular Stage

Teeth develops into four cusps on molars, making it the most advance stage in tooth evolution. Teeth resembles human permanent dentition (32 number of teeth and appearance). Herbivorous animals to omnivorous animals.