Effect of desensitizing treatments on the bond strength of universal adhesive to eroded root dentin- an in-vitro study

Erosive tooth wear can have a major impact on the long-term oral health, leading to dentin hypersensitivity (DH) due to the presence of open dentinal tubules. Desensitizing treatment may become essential in such situations before restoration of the defect. The purpose of this study was to evaluate in vitro the influence of a nanohydroxyapatite paste (nHAP) and low‑power diode laser (used as treatment modalities for DH) on the bond strength of the adhesive–dentin interface, on eroded root dentin (ERD).

Fifty-six single-rooted extracted human teeth were randomly assigned to four groups (n = 14). Samples were eroded by immersion in hydrochloric acid solution (0.01 M; pH = 1.2) and treated with: Group I- no treatment, Group II- nHAP, Group III- diode laser (940 nm), and Group IV- nHAP + diode laser. A shear strength test was performed to obtain the bond strength to dentin in megapascals (MPa).

Data was analyzed using one-way ANOVA and post-hoc tests. The mean difference was significant at the 0.05 level. Group II showed the highest mean value of shear bond strength. Group I (Positive control) showed the lowest values of bond strength. Group IV also showed improved bond strength as compared to Group III.

The use of an nHAP containing remineralizing toothpaste for the treatment of DH in NCCLs improved the bond strength of the self-etch adhesive to eroded root dentin, irrespective of the association of the diode laser.