The tooth is one of the hardest structures in the vertebrate body and is used to break down food for the digestion process.
Anatomy of a normal tooth
A healthy tooth is composed of the following main elements:
An inner dental pulp that forms the soft centre of the tooth and contains nerves and blood vessels and extends into the root(s) of the tooth
The dentin, a calcified material that surrounds the pulp and lies underneath the enamel
The tooth enamel or the hard outer cover of the tooth
The structure of tooth enamel
The tooth enamel is a unique component of the tooth, mainly due to its high mineral content. The mineral is present in tightly packed crystallites that form around 87 percent of the tooth's volume and 95 percent of its weight. The crystals are arranged in bundles or prisms that extend from the inner dentine towards the surface of the tooth. It is this highly organized arrangement of the crystallites that make tooth enamel the hardest substances in the vertebrate body.
In all other mineralized tissues including bones there is around 20% organic matter but in teeth there is around only 1%. The crystallites in the tooth enamel have around one thousand times the volume of similar crystals found in the bone, dentin and cementum of the tooth.
Damage to the tooth enamel or diseases of the tooth enamel
Despite being the hardest material in the vertebrate body, tooth enamel can be rapidly destroyed by tooth decay. This is caused by acids that are released by bacteria as they process the sugars in food. This bacterial acids burns holes in the surfaces of the tooth, eating away at the enamel. Around 95% of the American population is affected by dental caries.
Another common disorder of the tooth enamel is an inherited condition called amelogenesis imperfect which causes malformation of the enamel. This is often seen in families and is passed on from parent to offspring.
Prevention of enamel loss
Some of the measures taken to prevent tooth decay are the same as those for preventing enamel loss and include:
Maintaining good oral hygiene - This can be achieved by brushing the teeth twice a day. People should also floss as this helps remove plaque and food particles that get stuck the between teeth in areas that the toothbrush fails to reach. It is recommended that people floss at least once a day in addition to brushing the teeth.
Rinsing with mouthwash - Dental mouthwashes, especially those containing fluoride, can also help prevent tooth decay.
Avoidance of excess sugary foods, sugary and fizzy drinks and chocolates, which can all damage the teeth by accelerating tooth decay. Smoking is also associated with tooth decay. Diet and lifestyle changes along with good oral hygiene can keep tooth decay at bay.
Adults should get at least one dental check up every two years. Those under 18 years of age need annual checks, while younger children benefit from being checked every 4 to 6 months to detect any plaque formation or tooth decay early on.
Reviewed by Sally Robertson, BSc