Researchers with the Department of Pediatric Dentistry at the University of Hong Kong Faculty of Dentistry have developed a bioactive peptide that coats tooth surfaces to help prevent new cavities and heal existing ones in lab experiments.
Conventional treatment for cavities removes decayed tissues and fills the hole with materials such as amalgam or composite resin, which can damage healthy tissue and cause severe discomfort for patients, the researchers said.
Instead, the researchers have developed a two-pronged strategy. First, it prevents colonization of the tooth surface by the plaque-forming bacteria that cause cavities. Second, it reduces demineralization while increasing remineralization.
The researchers based their anti-cavity coating on a natural antimicrobial peptide called H5. Produced by human salivary glands, H5 can adsorb onto tooth enamel and destroy a broad range of bacteria and fungi.
To promote remineralization, the researchers added a phosphoserine group to one end of H5, which they thought could help attract more calcium ions to repair the enamel than natural H5. They then tested the modified peptide on slices of human molars.
Compared with natural H5, the new peptide adsorbed more strongly to the tooth surface, killed more bacteria and inhibited their adhesion, and protected teeth from demineralization. Both peptides promoted remineralization to a similar degree.
The researchers believe their work may lead to people applying the modified peptide to their teeth as a varnish or gel after brushing to protect against tooth decay.