Evaluation of the remineralisation effect and biocompatibility of boron-doped bioactive glass material on artificial...

Root surface caries, which frequently occur due to ageing and periodontal procedures, often require minimally invasive approaches, especially in molar teeth where access is limited. This study aimed to analyse the remineralisation effects and biocompatibility of experimental bioactive glass-containing materials modified through various boron concentrations on root surface caries.

For the synthesis of the experimental bioactive glass, a rapid alkali-mediated sol-gel was applied. H₃BO₃ was included in the composition for boron modification. Forty caries-free human molar teeth were used. Artificial root caries were formed after 15 days of incubation with a demineralisation solution. The teeth were randomly divided into four groups (n = 10) as GroupF: Fluoride varnish, GroupBG: Experimental bioactive glass, GroupBG-7: Experimental bioactive glass modified with 7% boron and GroupBG-14: Experimental bioactive glass modified with 14% boron. Microhardness and laser fluorescence measurements were conducted for each sample at baseline, after demineralisation and after treatment. The SEM-EDS analysis was performed. The cell viability was evaluated after 24 and 48 h of incubation using the human dermal fibroblast cell line (CCD-1072Sk) and the WST-1 viability assay. For statistical analyses, ANOVA, Tukey, Bonferroni, and one-sample t-tests were used (p < 0.05).

No statistically significant differences were detected among the groups in terms of microhardness. Laser fluorescence measurements showed a significant difference in Group BG-14 compared to other groups. The SEM-EDS indicated that Group BG-7 exhibited higher Ca/P ratios and favourable elemental distributions, with surface morphology comparable to fluoride-treated dentine. In the 24-h cytotoxicity assay, fluoride was cytotoxic at all doses, while the experimental bioactive glass and boron-modified groups only showed cytotoxicity at high doses. Low doses of boron-modified bioactive glass promoted fibroblast proliferation. Boron-doped bioactive glasses significantly improved root surface remineralisation and supported fibroblast viability, with 7% and 14% boron groups demonstrating enhanced mineral deposition and reduced cytotoxicity compared to fluoride.

The study revealed that all treatment groups significantly improved root surface remineralisation. Boron-doped bioactive glass groups showed increased mineral deposition and reduced cytotoxicity compared to fluoride. These findings suggest that boron-doped bioactive glasses may offer a biocompatible alternative for the minimally invasive treatment of root caries.