The Antibacterial Effect of Tetracycline-loaded Mesoporous Silica Nanoparticles in the Gingival Fluid at Implant-abutment Junction: A Randomized Clinical Trial Study

Introduction: Dental implant failure due to periodontal disease caused by anaerobic pathogens occurs, especially in the first year of implant placement. The aim of this clinical trial study was to compare the antibacterial effect of tetracycline gel and gel containing tetracyclineloaded mesoporous silica nanoparticles (MSNs) in the gingival crevice fluid of the implantabutment junction as a randomized clinical trial study. Materials and Methods: Fourteen patients applying for implants in the posterior mandibular region were included in the study. During the uncovering session, tetracycline gel and gel containing tetracycline-loaded MSNs were placed in two implants and no substance was placed in the control group. Then, in three sessions, including molding, prosthesis delivery, and one month after delivery, the patient's gingival fluid was sampled and the number of bacteria in the gingival fluid was measured by colony-forming units (CFU/mL). Results: The results of this study showed that in all three stages of sampling, the use of tetracycline gel and gel containing MSNs loaded with tetracycline significantly reduced the CFU/mL of gingival crevice fluid compared to the control group. Tetracycline-loaded MSNs gel showed significantly lower CFU/mL than tetracycline gel. The release of tetracycline from nanoparticles keep continue for a longer time compared to tetracycline gel. Conclusion: The use of nano-based delivery systems containing antibiotics inside the implant fixture can reduce the bacterial count of the implant-abutment junction and then improve implant stability.