Minimally invasive caries removal using bio-active glass air-abrasion.

OBJECTIVES: Alumina air-abrasion has been used to clean teeth and shown to over-prepare access cavity preparation to caries. This study investigated the working hypothesis that bio-active glass air-abrasion is more self-limiting than alumina for minimally invasive caries removal. METHODS: Human extracted molars were scored visually using ICDAS II criteria, divided into sound and carious groups and air-abraded with alumina (n=10) and bio-active glass (n=10) in each group, using identical operating parameters. The amount of enamel removed was semi-quantitatively assessed using scanning electron microscopy. Operating time was recorded. RESULTS: Bio-active glass abrasion removed extrinsic stain and substantial quantities of enamel from all carious fissures but not from sound, where only minimal microscopic surface modifications were observed. Alumina air-abrasion resulted in faster extrinsic stain and clinically substantial enamel removal in both sound and carious groups equally. CONCLUSIONS: Bio-active glass air-abrasion appeared to show a significant self-limiting tendency towards demineralised enamel and extrinsic stain removal but was slower in comparison to alumina air-abrasion. Self-limiting bio-active glass air-abrasion could be used clinically to clean teeth, detect caries and minimally prepare carious enamel as part of MI caries access or placing a sealant restoration.