Abstract
Objectives. Caries at the interface of dental materials and mineralized tooth structure continues to be a significant issue in oral healthcare. The objectives of this study were to demonstrate the effect that microencapsulated water has on charging an orthodontic cement and pit and fissure sealant with fluoride by toothbrushing, demonstrate the slow, sustained release of calcium, fluoride and phosphate ions from these materials initially formulated with remineralizing agents, examine the effect of microcapsules on cement adhesion to enamel and examine if a pit and fissure sealant releasing remineralizing ions promotes enamel fluoride uptake by demineralized tooth structure.|Methods. Cements and sealants that contained microcapsules with water and controls without microcapsules were brushed with over-the-counter toothpaste; fluoride release was measured. Materials that contained microencapsulated solutions of 5.0M Ca(NO3)2, 0.8M NaF, 6.0M K2HPO4 or a mixture of all three were prepared. Ion release profiles were measured as a function of time. Adhesion measurements were performed with an Instron test frame loading orthodontic brackets to failure. Enamel fluoride uptake by demineralized tooth structure was determined by a modified version of the FDA Method 40.|Results. A greater fluoride charge and release from toothbrushing was demonstrated compared to a control material with no microcapsules. Sustained release of remineralizing ions from cement and sealant formulated with preloaded microencapsulated ions was demonstrated. Adhesion of orthodontic cement that contained microencapsulated remineralizing agents was 8.5±2.5 MPa compared to the control without microcapsules, which was 8.3±1.7 MPa. Fluoride uptake by demineralized enamel was significantly increased compared to a control sealant manufactured without microcapsules. Bovine enamel that contained 2.2±2.1 μg F/g of enamel prior to exposure to a sealant without microcapsules had 2.3±0.5 after 90 days. Enamel exposed to sealant with 5w/w% NaF microcapsules went from 3.5±3.5 μg F/g of enamel prior to exposure to 148±76 after 90 days. Enamel exposed to sealant with 2w/w% NaF, 2w/w% Ca(NO3)2 and 1w/w% K2HPO4 microcapsules increased from 1.7±0.7 μg F/g of enamel prior to exposure to 190±137 after 90 days.|Significance. Polyurethane based microcapsules within dental sealants and cement pastes contain bioactive properties and are promising for remineralization.