Nanofilled/nanohybrid and hybrid resin-based composite in patients with direct restorations in posterior teeth: A systematic review and meta-analysis

Objective: A systematic review and a meta-analysis were performed to answer the following research question: Are there differences in the color match and surface texture of nanofilled/nanohybrid and hybrid composite in patients with direct posterior restorations? Data: Randomized clinical trials that compared nanofilled/nanohybrid and hybrid composite in direct restoration in posterior teeth were included. For the analysis of the bias the risk of bias tool (RoB) was used. Metaanalyses of different pairs (nanofilled vs. hybrid and nanohybrid vs. hybrid composite) were conducted for surface texture and color match and other secondary outcomes at different follow-ups, using a random effects model. Heterogeneity was assessed with the Cochran Q test and I2 statistics. GRADE was used to assess the quality of the evidence. Sources: A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library and SIGLE, without restrictions. IADR abstracts (2001-2019), unpublished and ongoing trials registries, dissertations and theses were also searched. Study selection: 28 studies remained. No study was considered to be at low RoB; four studies were judged to have high RoB, and the remaining were judged to have unclear RoB. Results: For the primary and secondary outcomes variables no significant differences were detected between nanofilled/nanohybrid restorations and hybrid composite restorations in any of the study follow-ups (p> 0.08). The body of evidence for surface texture and color match was classified as moderate or low. Conclusion: No evidence of difference was found between nanofilled/nanohybrid and hybrid composite in any of the clinical parameters evaluated.