Hong Kong, Jan 23 (IANS): Researchers have developed a bioactive peptide that coats tooth surfaces, helping prevent new cavities and heal existing ones in lab experiments.

Cavities, or dental caries, are the most widespread non-communicable disease globally, according to the World Health Organisation.

Having a cavity drilled and filled at the dentist's office can be painful, but untreated caries could lead to worse pain, tooth loss, infection, and even illness or death.

Conventional treatment for dental cavities involves removing decayed tissue and filling the hole with materials, such as amalgam or composite resin.

However, this procedure can damage healthy tissue and cause severe discomfort for patients.

For the findings, published in the journal ACS Applied Materials & Interfaces, research team from the Hong Kong University in China, wanted to develop a two-pronged strategy to prevent and treat tooth decay.

Prevent colonisation of the tooth surface by the plaque-forming bacteria that cause cavities, and reduce demineralisation, or the dissolving of tooth enamel, while increasing remineralisation, or repair, said study researchers Hai Ming Wong and Quan Li Li .

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 remineralisation, the team 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.

According to the study, they 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 demineralisatios, the study said.

Surprisingly, however, both peptides promoted remineralisation to a similar degree.

After brushing, people could someday apply the modified peptide to their teeth as a varnish or gel to protect against tooth decay, the researchers said.