Shear Bond Strength of Biointeractive Restorative Materials to NeoMTA Plus and Biodentine

The bonding compatibility between calcium silicate-based bioceramic cements and restorative materials is critical for long-term success in pediatric dentistry. This study compared the shear bond strength (SBS) of contemporary biointeractive restorative materials to two widely used bioceramics, NeoMTA Plus (NM) and Biodentine (BD).

Eighty acrylic resin blocks with standardized cavities were filled with either NM or BD (n = 40 each) and subdivided into four restorative groups: nanohybrid composite (Filtek Ultimate), giomer (Beautifil II), bioactive restorative (Activa BioActive Restorative), and high-viscosity glass ionomer cement (Fuji IX GP Extra) (n = 10 each). All restorations followed a standardized etch-and-bond protocol. SBS was measured using a universal testing machine, and failure modes were assessed under a stereomicroscope. Data were analyzed using one-way ANOVA and Tukey's HSD (p < 0.05).

BD exhibited significantly higher SBS values than NM (p < 0.001). In the BD group, Filtek Ultimate and Beautifil II achieved the highest and statistically comparable SBS, outperforming Activa BioActive Restorative and Fuji IX GP Extra (p < 0.05). In the NM group, no significant differences were found among materials. Adhesive failures predominated in NM (85%), while BD showed more cohesive failures (50%).

Biodentine demonstrated superior bonding stability to restorative materials, with composite resin and giomer performing best. Giomer's bioactivity and ion release make it a viable alternative to composite resin in suitable clinical contexts.