Abstract
INTRODUCTION: Polymethyl methacrylate (PMMA) resins are widely used in dental prostheses due to their excellent physical, mechanical, and aesthetic properties. However, their susceptibility to microbial colonization can compromise oral and systemic health. Titanium dioxide (TiO₂), with its photocatalytic activity, has gained attention for its antimicrobial potential. This systematic review investigates how the physicochemical properties of TiO₂ affect its antimicrobial efficacy in PMMA-TiO₂ composites, aiming to optimize their performance and clinical effectiveness. METHODS: PubMed, Embase, Scopus, ScienceDirect, Web of Science, Google Scholar, and ProQuest were searched in October 2024. Articles were selected in two stages by two blinded researchers based on predefined eligibility criteria. Risk of bias was assessed using the RobDEMAT tool. RESULTS: A comprehensive search identified 1464 articles, which were screened by title and abstract according to inclusion criteria. Of the 28 studies selected for full-text review, 24 were included in this systematic review, all of which were in vitro studies. Due to the high heterogeneity of the selected studies, which prevented statistical analysis of the data, a descriptive analysis was performed. CONCLUSIONS: The balance between concentration, size, crystallinity, and surface morphology can enhance TiO₂ photocatalytic activity and reduce microbial adhesion. Synthesis and functionalization strategies can overcome limitations, expanding the clinical applicability, efficiency, and durability of PMMA-TiO₂ composites.