The authors thank all the authors who responded to their requests and provided useful information that made it possible to complete this systematic review and meta-analysis.

Purpose: To evaluate the influence of connective tissue graft on the soft tissue thickness and aesthetics around single implants placed in the aesthetic zone of the maxilla. Materials and methods: Forty-two patients with indications for single implant placement in the aesthetic zone were randomly allocated into two groups: the implant group (implant insertion) and the implant + connective tissue graft group (implant insertion and placement of a 1.50-mm-thick connective tissue graft). Clinical evaluations were performed at baseline, 4 months after surgery (prior to prosthetic reconstruction) and 1 year after crown placement to assess tissue thickness at the crestal aspect and the buccal aspect, buccal defects, keratinised tissue width and proximal bone resorption. Aesthetics were assessed using the pink aesthetic score index, and postoperative discomfort and pain tests were also performed. Results: Only the implant + connective tissue graft group presented a significant increase in tissue thickness at the buccal aspect, with 2.36 ± 0.94 mm at baseline, 3.35 ± 1.00 mm after 4 months and 3.23 ± 0.77 mm after 1 year (P < 0.05), whereas no change was observed in the implant group. The difference between the two groups was significant after 4 months and 1 year (P < 0.05). The implant + connective tissue graft group also showed a greater reduction in buccal defects after 1 year compared to the implant group (Δ −0.50 ± 0.70 mm and Δ −1.80 ± 1.30 mm, respectively; P < 0.05). After 1 year, a significant intergroup difference in proximal bone resorption was observed, with the implant + connective tissue graft group showing less bone resorption compared to the implant group (0.75 ± 0.20 mm and 0.92 ± 0.30 mm, respectively; P < 0.05). Conclusions: Placement of a connective tissue graft simultaneous to single implant insertion in the anterior maxillary region can increase the thickness of the peri-implant mucosa and reduce proximal bone resorption.