Hybrid Sonochemical-Pressure Fabrication of tri-element nanohybrids for advanced biological protection in resin and metal dental crowns.

Premature failure of dental crowns is frequently associated with bacterial colonization, secondary caries, and persistent biofilm formation at restoration interfaces. In this study, Sn-Ag-Al trimetallic nanohybrids were synthesized through a novel hybrid sonochemical-pressure-assisted approach and ultrasonically embedded onto metal and resin dental crowns to develop durable antibacterial and antibiofilm coatings. Structural and surface characterization using XRD, FE-SEM-EDX, BET, and Raman analyses confirmed the formation of crystalline nanohybrids with homogeneous elemental distribution, nanoscale morphology, and favorable surface properties for crown adhesion. Antibacterial evaluation revealed a concentration-dependent inhibitory effect against Escherichia coli and Staphylococcus aureus, with zones of inhibition increasing from 12.6 and 9.5 mm at 50 µg/mL to 23.4 and 21.9 mm at 250 µg/mL, respectively. The coated crowns exhibited strong antibiofilm activity, achieving up to 85.4 % inhibition against E. coli and 81.3 % against S. aureus. Cytocompatibility studies using human gingival fibroblasts demonstrated high cell viability at clinically relevant concentrations, confirming the biocompatible nature of the coating. Furthermore, FESEM-EDX analysis showed that the ultrasonically deposited trimetallic layer remained structurally intact after repeated saline-washing cycles, retaining significant antibacterial functionality and indicating excellent coating durability under simulated oral conditions. The enhanced performance is attributed to the synergistic antibacterial action of Sn, Ag, and Al combined with cavitation-assisted nanoparticle anchoring generated during ultrasonic processing. This work introduces a multifunctional, wash-resistant trimetallic coating platform that integrates sonochemistry and pressure-assisted synthesis for long-term protection of dental restorations. The findings highlight the potential of ultrasonic surface engineering in developing next-generation infection-resistant dental biomaterials and advanced restorative devices.