Introduction: For optimal dental implant esthetics the transition of a circumferential implant platform to a proper cervical anatomy has been emphasized. This transition is facilitated by the macro-design of the transmucosal portion of the abutment-restoration complex at the provisional and final stages of implant prosthetic therapy. There is limited information from human studies assessing the impact of abutment macro-design on peri-implant tissue dimensional changes. Aim: The aim was to evaluate the peri-implant tissue levels over a 1-year period for implants connected to either convex or concave final abutments at the time of implant placement. Methods: Twenty-eight patients with one missing maxillary premolar randomly allocated to receive one single implant with abutments of different emergence shape configuration. Patients of the CX Group had abutments with convex emergence shape and patients of the CV Group had abutments with concave emergence shape. Clinical and radiographic data collected at the time of implant placement (T0), final prosthesis delivery (T1) and 12 months following implant placement (T2). Results: There was 0.42-0.55mm more bone remodeling occurred in the CX group. Soft tissue thickness was 21-37% greater in the CV group. There was a statistically significant moderate correlation between buccal bone thickness and recession T0-T2. No statistically significant difference found in recession between the two groups. Conclusion: A concave abutment configuration was associated with less bone remodeling and had greater horizontal soft tissue thickness. However, no difference was seen in the amount of recession between the two groups. Bone thickness was found to be the most significant factor for gingival recess.