Clinical outcomes of implants placed with transcrestal maxillary sinus elevation: a systematic review and meta-analysis

This systematic review and meta-analysis assesses the clinical outcomes of implants inserted during or following transcrestal sinus lifts. The study protocol was prospectively registered on PROSPERO (CRD42024504513). PubMed, Web of Science, Embase, and Scopus databases were searched up to 21 February 2024, and randomised clinical trials utilising transcrestal sinus lifts were included. Qualitative and quantitative syntheses were conducted. A random effects model was used to pool the survival rate of implants placed with transcrestal sinus lifts using hand osteotomes without grafting, along with meta-regression and subgroup analyses. Funnel plots and Egger’s linear regression were used to explore possible publication bias. Probabilities of less than 0.05 were considered significant. A total of 1807 records were identified after the initial search. Seventeen studies were included with 10 of them considered for meta-analysis. Studies used hand osteotomes, a combination of piezoelectric and hand osteotomes, drills, and smart lifts for sinus elevation. Only studies that used hand osteotomes reported subsequent vertigo and dizziness in patients. The meta-analysis showed a 100% (95% CI: 99% to 100%) survival rate for both grafted and non-grafted transcrestal sinus lifts using hand osteotomes. Meta-regression showed that follow-up time did not significantly affect the implants’ survival. Subgroup analyses showed no significant difference between bone-level and tissue-level implants and one-stage or two-stage implants. On considering the limitations of this study it can be concluded that closed maxillary sinus elevation can be considered a relatively safe technique that is associated with a high survival rate. However, caution should be taken when using hand osteotomes because of a higher rate of sinus lining perforation and reported patient vertigo.