Socket Shield Technique to Improve the Outcomes of Immediate Implant: A Systematic Review and Meta-Analysis

Background: The socket shield technique (SST) could address the challenges in immediate implant placement by minimizing post-extraction bone resorption while maintaining soft tissue levels. This study aimed to summarize the available evidence and systematically assess the effectiveness of SST immediate implant placement regarding all outcomes (bone loss, esthetics, implant stability, probing depth, complications, and survival rate). Methods: We searched seven electronic databases through April 2023 to identify randomized clinical trials that assessed the effect of immediate implant placed with SST (test group) versus other implant placement protocols without SST. The risk of bias was assessed using Cochrane's randomized trial quality assessment Tool (RoB 2.0). Random-effects meta-analysis was conducted, with mean difference and 95% confidence intervals (MD, 95% CI) as effect estimates. We used the GRADE approach to assess the certainty of evidence. Results: Twelve RCTs, involving 414 immediate implants, placed in 398 patients, were included. Meta-analyses revealed that the immediate implants placed with SST had a statistically significant decrease in horizontal (MD = -0.28, 95% CI [-0.37, -0.19], p < 0.0001), vertical (MD = -0.85, 95% CI [-1.12, -0.58], p < 0.0001), and crestal (MD = -0.35, 95% CI [-0.56, -0.13], p = 0.002) bone loss, as well as probing depth (MD = -0.64, 95% CI [-0.99, -0.29], p = 0.0003). Additionally, SST had a significant increase in implant stability (MD = 3.46, 95 % CI [1.22, 5.69], p = 0.002) and pink esthetic score (MD = 1.60, 95% CI [0.90, 2.30], p < 0.0001). Only two studies reported shield exposure incidences in the SST group; however, all studies revealed no implant failure and a 100% survival rate. The evidence certainty was assessed as very low. Conclusions: Based on limited evidence, SST was more effective in minimizing bone resorption and improving implant stability and esthetic outcomes than conventional immediate implant placement. Still, SST could not be recommended as a routine clinical protocol due to the lack of a standardized surgical approach; thus, further high-quality RCTs are required to support this conclusion.