Koutouzis T, et al. - Researchers evaluated implants connected to either convex or concave final abutments at the time of implant placement for the peri-implant tissue levels over a 1-year period. They allocated 28 patients with one missing maxillary premolar to receive one single implant with abutment of either convex or concave emergence shape, in this randomized, double-masked, controlled clinical study. At the time of implant placement, final prosthesis delivery and 12 months following implant placement, they collected clinical and radiographic data. Outcomes do not support any effect of abutment macro-design on peri-implant mucosa margin position changes over time.