Bond strength durability of three bioactive restorative materials to silver diamine fluoride treated artificially demineralized dentine.

Background: This study aimed to assess the impact of 38% silver diamine fluoride (SDF) treatment regarding microtensile bond strength of three bioactive restorative materials to artificially induced caries-affected dentine after thermocycling; Alkasite restorative material, Glass hybrid restorative (GHR) and Resin modified glass ionomer (RMGI).

Methods: A total of 60 artificially demineralized human mid-coronal dentine specimens were randomly allocated into two main groups (n = 30 each): a control group and an SDF-treated group (38% SDF). Each group was additionally split into three subgroups (n = 10) regarding the type of restorative material (Alkasite; Cention N, GHR; EQUIA Forte fil, RMGIC; Fuji II LC). 10,000 cycles of thermal cycling were conducted alternating between 5 ºC - 55 ºC with a dwell-duration of 15 s. µTBS was assessed with the aid of a universal testing machine (Instron Co., Canton, MA-USA) occupied with a 50 kg load cell, operating at 0.5 mm/min cross-head speed till failure. µTBS results, measured in MPa, were collected and statistically analyzed with two- and one-way ANOVA succeeded by Tukey's post hoc test and student's t-test (α = 0.05).

Results: There was a significant reduction in µTBS after SDF application in all tested groups (p ≤ 0.05). Cention N recorded the highest bond strength values in both control and SDF-treated conditions, while EQUIA Forte Fil had the lowest.

Conclusions: Based on the limitations of this laboratory study, the application of 38% SDF directly preceding restoration with Alkasite, GHR or RMGI resulted in a significant deterioration in bond strength to artificially induced caries-affected dentine.