Teeth
- Accessory digestive organs housed within the oral cavity.
- 32 permanent teeth in the adult, which replace the 20 deciduous teeth, (aka, milk teeth) that are lost during childhood.
4 permanent tooth types:
- Incisors, which slice and bite through foods
- Canines, which puncture foods
- Premolars, which crush and grind foods
- Molars, which also crush and grind foods
Dental arches
- Teeth in anatomical position
- Quadrants along the sagittal plane:
- Upper (aka, maxillary) quadrants – right and left upper
- Lower (aka, mandibular) quadrants – right and left lower
Tooth Surfaces
- Vestibular surface
- Faces the lips and cheeks; the space between the teeth and overlying soft tissues is the vestibular cavity.
- Can also be called the labial or buccal surface, which depends on whether the tooth faces the lips or cheeks.
- Lingual surface
- Faces the tongue ("lingual" refers to the tongue)
- Occlusal surface
- Faces the tooth of the opposite jaw; it is where the teeth from the superior and inferior jaws meet.
- Occlusal surfaces of the premolars and molars have prominent ridges, called cusps, that mash the foods.
- Premolars typically have two cusps (and are therefore referred to as the bicuspids), and molars typically have 3-5.
- Mesial surface
- Faces the midline of the mouth
- Distal surface
- Faces away from the midline.
The mesial and distal surfaces of the teeth are collectively called proximal surfaces.