Secret life of tooth enamel
Tooth enamel consists of calcium and phosphate arranged in a crystal lattice – and is the hardest tissue in the human body. Sounds a lot like geology! And the common idea that it just wears, or erodes over time also sounds like the life of rocks.
Demineralisation then remineralisation. . .
In fact, enamel has a more active existence than many people realise. The mineral content and formation deteriorate and recover with every meal. The mineral structure breaks down in the presence of acids, and is restored from minerals naturally present in saliva.
These acids come from foods and drink we choose, and also from the activity of bacteria in plaque after we eat and drink. During and after eating and drinking, our teeth receive an acid wash which leaches minerals from tooth enamel. This everyday process is known as demineralisation.
Normal healthy saliva contains calcium and phosphate that replace what was lost. This rebuilding of the crystal lattice and therefore, strengthening of enamel is known as remineralisation. This process is now known to repair pitting which is the earliest stage of a cavity/decay.
What this means for snacking or sipping all day on sweets and sugary drinks:
A whole bag of sweets or packet of biscuits ‘grazed on’ over a day leaves tooth enamel exposed to continual acid washes and insufficient time to remineralise or recover. Dentists recommend sweets and ‘sodas’ as part of a meal, where other foods can counter the effect of acids consumed. And feeling satisfied after a meal reduces the desire for a top-up snack.
What about tooth brushing straight after my bag of sweets?
Vigorous brushing (especially with a medium or firm-bristled brush) and poor technique adds abrasive forces to weakened (demineralised) enamel. A better idea is to rinse with or drink water, and brush later. (Remineralisation is thought to commence twenty minutes after eating, and the duration will depend upon factors including the food type eaten, saliva quality etc) Don’t rush to the tooth brush!
Knowing this secret can only help your tooth enamel! There are even foods, with a high pH, that are considered to reduce the acidic environment . . .