Soft Tissue Parameters and Esthetic Index Changes in Platform Switching Implant: A Systematic Review and Meta-Analysis

Purpose: The purpose of this study was to perform a systematic review and meta-analysis to critically evaluate the available literature to statistically analyze the effects of platform matched (PM) and platform switching (PS) implants on the peri-implant soft tissue changes and esthetic outcomes. Materials and methods: Electronic databases of the Cochrane Library, Embase, CINAHL and PubMed were searched for human randomized controlled trials (RCTs) with clearly outcome measurement in comparison between PM and PS implant. Primary outcomes included midfacial keratinized gingiva (KG) thickness, width of KG, marginal gingiva height gain, papilla height, and pink esthetic score. Secondary outcomes included bone level, probing depth, plaque index, and sulcus bleeding index. All the included studies had to follow up for at least 1 year after function. Results: A total of 7 RCTs were included in the meta-analysis. Midfacial KG thickness (weighted mean difference (WMD) = 1.34 mm, P < 0.0001), marginal gingiva height (WMD = 0.30 mm, P = 0.01), papilla height (WMD = 0.18 mm, P = 0.003), bone level (WMD = 0.34 mm, P < 0.00001) and probing depth (WMD = -0.22 mm, P = 0.002) demonstrated statistically difference in comparison of PS and PM implants. The result of width of KG (P = 0.92), PES score (P = 0.73), plaque index (P = 0.97) and sulcus bleeding index (P = 0.78) showed no statistical difference. Conclusion: Meta-analysis showed better performance of midfacial KG thickness, marginal gingiva height and papilla height in PS implant than that in PM implants. No statistically difference was found in width of KG and PES score between PS implants and PM implants.