Abstract
BACKGROUND: Graphene has been successfully used for years in several applications. It had great potential for use in the medical field. Recently, incorporating graphene into dental biomaterials manufacturing has revolutionized prosthodontics. There is no clear data about the benefit and concentration of adding adding graphene or its derivatives into polymers used in prosthodontics. Accordingly, this review aimed to test the hypothesis that incorporating graphene or its derivatives into prosthodontic polymers, even at low concentrations, improves mechanical properties compared to conventional materials, without compromising biocompatibility. METHODS: The databases (PubMed, Web of Science, Cochrane Library and Willey) were searched based on the designed search strategy. The search strategy was developed using accessible terms, such as, 'graphene,' 'prosthodontic polymers,' 'PMMA,' 'mechanical properties,' and 'dental nanocomposites.' including medical search topic terms (MESH) where possible, in line with the PICO question. The search process did not include any filters for date or language. Quality assessments were undertaken in the included articles. Meta-analysis was calculated using the standardized mean difference as an effect size, considering the random effect model. Cochran Q and inconsistency I(2) tests were applied for testing heterogeneity. Based on nanofillers' concentration, subgroup analysis was applied and interpreted as forest plots. Sensitivity and publication bias testing were also considered before interpretation. RESULTS: Out of 756 records from databases and other sources, only 22 articles were considered for data extraction according to the inclusion criteria. Eighteen studies were valid for meta-analysis, including seven material properties: flexural strength, impact strength, compressive strength, Shore D hardness, Shore A hardness, Vicker's hardness and surface roughness. Subgroup analysis, which relied on nanofiller concentration, showed enhanced outcomes at low concentrations. Low sensitivity and variable publication bias levels were recognized. CONCLUSIONS: While low-concentration graphene shows optimized prosthodontic nanocomposites' properties, high heterogeneity and methodological variability across studies preclude definitive clinical recommendations. Future research must prioritize standardized protocols and clinical validation. TRIAL REGISTRATION: PROSPERO CRD42024522295.