Soft‐tissue volume augmentation during early, delayed, and late dental implant therapy: A systematic review and meta‐analysis on professionally determined esthetics and self‐reported patient satisfaction on esthetics

The objective of the study was to assess the effect of soft-tissue volume augmentation during early, delayed, and late dental implant therapy in terms of professionally determined esthetics and self-reported patient satisfaction on esthetics. For this, a comprehensive electronic literature search was performed to identify randomized clinical trials (RCTs) and controlled clinical trials (CCTs) reporting professionally determined esthetic outcomes and self-reported patient satisfaction on esthetics (primary outcomes) during early, delayed, and late dental implant placement comparing soft-tissue volume augmentation to the absence of soft-tissue grafting (control) (PICO 1) or comparing various soft-tissue augmentation techniques, procedures, and materials (PICO 2). Secondary outcomes were mucosal thickness (MT), intra- and postoperative complications, marginal soft-tissue-level changes, keratinized tissue width, radiographic marginal bone levels, and clinical parameters for the diagnosis of peri-implant tissue health. The standard mean differences (SMD)/weighted mean differences (WMD) were estimated for the Pink Esthetic Score (PES), self-reported patient satisfaction assessed by Visual Analog Scale (VAS) and MT gain for PICO 1 and PICO 2 by employing a random effect model. Five RCTs were included for PICO 1, whereas 7 RCTs and 1 CCT addressed PICO 2. PICO 1: The SMD for the PES between autogenous soft-tissue grafting (SCTG) and the absence of grafting (control group) was 0.47; 95% CI [-0.15, 1.09; p = 0.14] based on 5 RCTs. The SMD for the VAS values for patient-reported satisfaction on esthetics in the SCTG and control group was 0.46; 95% CI [-0.12, 1.03; p = 0.12] (2 RCTs). The WMD for gain of MT amounted to 1.06 mm; 95% CI [0.81, 1.31; p = 0.00] in favor of the SCTG group (3 RCTs). PICO 2: The SMD for the PES comparing collagen-based matrices (CM group) to the SCTG group was -0.32; 95% CI: (-0.57, -0.07; p = 0.01), in favor of the SCTG group (5 RCTs and 1 CCT). The SMD for the VAS for patient-reported satisfaction on soft-tissue esthetics was 0.24; 95% CI: (-0.31, 0.78; p = 0.40) (2 RCTs comparing CM vs. SCTG). The WMD for gain of MT was -0.27 mm; 95% CI: (-0.36, -0.17; p = 0.00), significantly favoring the SCTG group (4 RCTs). Professionally and patient-assessed outcomes showed no substantial differences between autogenous soft-tissue grafting and the absence of grafting for early, delayed, and late implant placement. However, autogenous soft-tissue grafts led to significantly improved esthetic outcomes as assessed by professionals compared to soft-tissue substitutes. Patient-assessed outcomes, nevertheless, were similar regardless of the grafting material (i.e., SCTG or soft-tissue substitute). Therefore, autogenous soft-tissue grafting, though, resulted in a considerably higher gain in mucosal thickness compared to both the absence of soft-tissue grafting and the use of soft-tissue substitutes. Complications and adverse events were rarely reported by the included studies, thus suggesting that many trials underreport harms (e.g., complications).