Improving caries-preventive effect of fissure sealants by using bonding agent

Objective To study the caries-preventive effect of bonding agent(Prime Bond NT) before placing fissure sealant under the condition of saliva contamination.Methods Thirty six caries-free maxillary premolars(extracted for orthodontic treatments) were randomly divided into three groups of 12 teeth each.Group 1 was treated with fissure sealant routinely(sealed with a resin based fissure sealant after phosphoric acid etching).Group 2 was slightly contaminated with saliva before routine sealant application.Group 3 was sealed with a total-etching adhesive(Prime Bond NT) after saliva contamination.After 100 thermo-cycling,the specimens were exposed to an in vitro microbial-based model to study the secondary caries-like lesions under fissure sealants.The degree of demineralization was assessed by Confocal Laser Scanning Microscope(CLSM) to measure four lesion parameters(area of fluorescence,total and average value of fluorescence,maximum depth of the lesion).The data were collected and analyzed with one-way ANOVA.Results The four lesion parameters of group 2 was significantly higher than those of group 1(P0.01).There was no significant difference regarding the extent of secondary caries-like lesion between group 1 and group 3(P0.05).Conclusion Saliva-contamination has negative effect on the fissure sealants.Total-etching adhesive(Prime Bond NT) can improve caries-preventive effect of fissure sealing under the condition of saliva contamination.