Caries, or tooth decay, is an extremely common disease. Getting a filling can be painful and damage healthy tooth tissue. Preventing caries from reaching the stage where this treatment is necessary would, thus, be beneficial.

Hai Ming Wong, The University of Hong Kong, China, Quan Li Li, Anhui Medical University, Hefei, China, and colleagues have developed a dual strategy to prevent and treat tooth decay using a bioactive coating for the tooth surface. The researchers aim to prevent the colonization of the teeth by the plaque-forming bacteria that cause cavities and to reduce demineralization, i.e., the dissolving of tooth enamel, while increasing remineralization. The researchers based their anti-cavity coating on the natural antimicrobial peptide Histatin 5 (H5). This peptide can adsorb onto tooth enamel and destroy a broad range of bacteria and fungi. The team added a phosphoserine group to one end of H5, which could help attract more calcium ions to repair the enamel compared with the natural peptide.

The researchers tested the modified peptide on slices of human teeth. Compared with natural H5, the modified peptide adsorbs more strongly to the tooth surface, kills more bacteria and inhibits their adhesion, and better prevents  demineralization. Both peptides promote remineralization to a similar degree. According to the team, consumers could apply the modified peptide to their teeth in the form of a varnish or gel.

• Constructing an Antibiofouling and Mineralizing Bioactive Tooth Surface to Protect against Decay and Promote Self-Healing,
  Li Zhou, Hai Ming Wong, Yu Yuan Zhang, Quan Li Li,
  ACS Appl. Mater. Interfaces 2019.
  https://doi.org/10.1021/acsami.9b19745