Comparative and Systematic Analysis of Nanocomposite Resins in Restorative Dentistry: Durability and Antimicrobial Properties

Background: Nanocomposite resins became promising materials in restorative dentistry due to the application of nanotechnology to improve durability and microbial resistance characteristics. This systematic review aimed to review the mechanical performance and antimicrobial efficacy of nanocomposite resins. Methods: A total of 93 studies were identified through a comprehensive database search of PubMed, Scopus, Web of Science, and Cochrane Library from 2010 to 2024. Studies were included if they evaluated the nanomaterials in dental composites, reported mechanical and antimicrobial properties, and utilized in vivo and in vitro experiments. Studies were excluded if they were reviews, commentaries, or conference papers and lacked quantitative data. Nanoparticles such as silver, zinc oxide, silica, and halloysite nanotubes were studied, and outcomes were measured, including flexural and compressive strength and antimicrobial activity against biofilms. The risk biases of studies were assessed using the Cochrane Risk of Bias tool. Results: A total of 15 studies were included in the systematic review table out of an initial pool of 93 studies further filtered down via the screening process. There were 6 in vitro, 5 experimental, and 1 hybrid study designs. Silver, zinc oxide, silica, and halloysite nanotubes were among the nanoparticles that were investigated. Mechanical properties were seen to be improved significantly, with flexural strength increased by up to 74% and compressive strength increased by 50%. Bacterial reduction rates of >99% were observed for silver and zinc oxide nanoparticle-incorporated composites. The lack of long-term data and nanoparticle agglomeration were identified as drawbacks. Optimal nanoparticle concentration was observed to be needed to balance mechanical and antibacterial properties via subgroup analyses. Discussion: While these advancements were significant, some gaps must be addressed. The lack of information about long-term performance under simulated oral conditions and the lack of testing against multispecies biofilms remained. Future studies should aim to optimize the formulations and conduct clinical trials that could validate efficacy and safety. The use of nanocomposite resins was an innovative approach to restorative dentistry that had the potential to offer durable, antimicrobial restorations.