Our mouth contains our teeth, which amounts to around 20% of the total surface area. There are two sets involved: the upper and lower set. The upper part takes up more space than the lower set. When your mouth closes, these two sets meet, forming your perfect pearly whites.

Before your food gets to your gastrointestinal area, the primary function of your teeth is to chew food. Formation of speech, contorting facial muscles forming various facial expressions, alignment and coloration are some of the other functions that our teeth are capable of. Our teeth are regular in shape, unchipped and sturdy (considering that no disorders or illnesses are found), and basically white overall, improving our appearances every time we smile.

Human beings need teeth for them to chew on food mechanically. On the other hand, animals not only use this to chew food – it is also for self-defense and weapons against attackers.

When a person is around six months old, there are twenty primary teeth (deciduous or milk teeth) that will have erupted. Permanent teeth will start to set in at around six years of life. A full set of teeth (32 teeth) will replace these deciduous teeth at the age of 20. Molars, however, may not erupt yet at this age.

There are three parts that composes your complete (32 in normal healthy adult) teeth: Enamel, Dentine and Pulp.

Imagine cutting a tooth lengthwise. You will see layers in the tooth and their relations with the gums and jawbone. These are the internal structures in your mouth.

Tooth crown, neck and root

The part of the tooth that is visible around your gums (gingival) is called a crown. In the middle of the root and the crown area, the neck of the tooth is found somewhere in the gum line. The gums that are fixed to the regions of your tooth is where you will find the root part. Molars and premolars have four roots in each tooth while canine and incisors have only one root embedded in the gums.

Your teeth are attached to your jaw for support. Your jaw is made out of alveolar bone, periodontal ligament and cementum which are sheltered by your gums. This whole structure is malleable, which enables you to withstand the mechanical act of chewing and opening and closing your mouth.

The tough coat surrounding the crown of your tooth is called Enamel. This covers the underlying dentine. Your tooth is supplied with nutrients primarily of calcium and phosphorus to give it its tough exterior. Apatite crystals are ‘non-living’ minerals which are generally found in your enamel composed of 96%. Although minerals keep your tooth sturdy, it can also make it brittle. Apatite crystals found inside the enamel are set in a rod- like line that covers the exterior part of your tooth. This is the reason your dentist always advice you to brush your teeth laterally instead of vertically. This is to prevent the wear down of the covering of your teeth.

The toughest part in the human body is the enamel. This is much tougher than your bones. Your mouth secretes acid which can kill bacteria -- and cause wearing of your enamel. This makes your teeth brittle. However, your mouth can absorb fluoride as your mouth initially digests down food. Toothpastes and drinking water all contain fluoride to enhance tooth durability.

Dentine is the most important part of your tooth. It has a yellow to white color, is tough, and has soft enamel, making it elastic even when compressed. Since dentin supports the whole teeth structure, it also confines the central chamber pulp. This structure has the ability to renew and replace when needed and is highly sensitive.

The structure consisting of soft tissue found in the central area of the tooth is called a Pulp. Although dentin and pulp have different features to consider (toughness), the functions of each are the same and inter-dependent, making it a single cohesive unit. The primary function of a pulp is for nutrition, production, fortification and replacement of surrounding dentin.

Cementum covers up the roots of your teeth and holds your teeth in place. It is composed of 50% mineralized connective tissue. Dentin and Cementum are both conjoined at the root of your teeth.