This note focuses on the second part of Specific Objective 2.7 of Section B of the CSEC Biology Syllabus, which refers to mastication, and the role of teeth in the mechanical breakdown of food.

Mastication can be defined as the mechanical breakdown of food by chewing. Mastication occurs mainly by the teeth, of which there are four types:

1. Incisors- Located at the front of the mouth, used for cutting of food.

2. Canines- The pointed teeth next to the incisors, used for tearing of food, especially meat.

3. & 4) Premolars and Molars- The flattened teeth towards the back of the mouth, used for the grinding and crushing of food into smaller pieces.

Note: Mastication is also aided by the jaw and tongue.

As seen from the above diagram, there are four constituent parts of the internal structure of a tooth:

1.      Enamel- The hard, outermost layer of the tooth, which protects the inner layers from damage from biting, chewing, exposure to bacteria.

2.      Dentine- Less hard than enamel, but provides strength and support to the tooth, and protects the pulp. Transmits signals from the external environment to the nerves in the pulp.

3.      Pulp- soft tissue containing blood vessels, nerves, connective tissue.

4.      Cement (cementum)- helps anchor the tooth to the gum.