Protective Tooth Coatings
What is hydroxyapatite? Well it's the main ingredient in tooth enamel and Japanese scientists from Kinki University have managed to create a 0.004mm coating made out of this mineral which can be used to coat teeth and pevent tooth decay altogether.
The crystals that form tooth enamel are hydroxyapatite crystals formed in bundles called prisms.
Tooth coatings are not new and non-permanent dental coatings have been tested in the past and shown to reduce a number of physical, chemical and biological 'irritations' on tooth enamel.
The recent Japanese development is unique because it uses the technique of making the coatings - in this case a very fine film only visible under microscope - out of hydroxyapatite or the very mineral that enamel is made from in the first place.
Dental sealants are not new and have been commercially available since the 1970s to protect against tooth decay most especially for the back molars which are the most vulnerable as brushing often missed the grooves and fissures in these back teeth.
In combination with fluoride toothpaste sealants have proved to be quite effective against food/carbohydrates which turn into acid, sit in the minute fissures in teeth and cause decay.The basic premise of sealants is that it is easier to prevent decay by coating teeth with plastic than fix cavities once the damage is done.
The process of applying the sealants is relatively easy - the teeth are cleaned, a gel is applied and then the sealant which takes about a minute to dry is applied. The resulting coating lasts 5-10 years.
However, there have been some problems with these thin plastic or self-curing sealants
These problems include:
- how long the sealant will give maximum protection/be effective
- minute splitting which means the very food that the sealant is designed to keep out can become trapped under or in the coating causing acid to build up and eventual cause what the sealant was designed to prevent; namely, decay.
- concern over the plastic sealant BPA which has been found in saliva after the application of these coatings. BPA is a plastic that has also been used in consumer products bottles and food containers and several warnings have been issued by a number of governments over its safety. In the US, the FDA (Food and Drug Administration) has warned of possible effects on unborn babies and young children.
The new Japanese coating which uses the main mineral in tooth enamel is still not full tested and it may be a while before it can be applied over the sensitive layer that runs below tooth enamel (the dentin) but cosmetically it is probably not too far away.
The Japanses scientists have successfully adhered this new enamel skin to discarded teeth but the procedure takes a lot longer than traditional coatings - at least one day to apply.