Synthetic enamel seals cavities painlessly

DENTISTS, put away your drills. Synthetic tooth enamel can seal tiny cavities without the pain, and with less damage to the patient’s teeth.

Cavities form when acid produced by mouth bacteria starts eating away at the tooth’s protective enamel layer. Early on, these lesions are too small for fillers such as resins to stick properly, so dentists have to drill bigger holes that destroy some healthy parts of the tooth.Now Kazue Yamagishi’s team at the FAP Dental Institute in Tokyo has found that a fine paste of hydroxyapatite crystals, the material of which natural enamel is made, can repair small cavities in just 15 minutes (Nature, vol 433 p 819). The paste fills cavities with long crystals that bond with the tooth’s own structure. But using it needs care. The strongly acidic mix required to promote crystal growth would be painful if it touched the gums.(Source: New Scientist magazine, February 2005)