The Remineralizing Potential of Nano Bioactive Glass Versus Nanohydroxyapatite on Dentine as Affected by PH Cycling

Objective: The aim of this study was to evaluate the remineralizing potential of nano bioactive glass (BG) in comparison with nano hydroxy appetite (HA) incorporated into adhesive on demineralized dentine as affected by PH cycling.Materials and Methods: sixty sound premolars were extracted for orthodontic treatment. Class I Cavities were prepared in premolars with a depth 3mm. The specimens were divided into three treatment groups including 20%BG incorporated into self-etch adhesive (3M ESPE), 20% HA incorporated also into self-etch adhesive, and gel of sodium fluoride NaF was used as a positive control. 37% phosphoric acid was applied for each cavity for lesion creation. Modified adhesive and composite restoration were applied according to the manufacture instructions. An in vitro pH cycling model was used to mimic oral cavity condition through treatment solutions, acidic buffer (4 hours ) and neutral buffer(20 hours) for 30 days. The specimens were evaluated for radiodensity using Digital Radiographic (DBSW software) and Environmental Scanning Electron Microscope (ESEM) at different stages of the study (before demineralization, after demineralization and after remineralization). The significance level was set at p ≤0.05. Results: all groups showed significant reminerlization. Groups with BG nanoparticles and HA nanorods showed a higher increase in the radiodensty of demineralized dentine than NaF group. BG group showed higher results under neutral condition.Conclusion: BG and HA modified adhesives may be valuable tools to enhance remineralization of affected dentin.