Minimally Invasive Single Implant Treatment (M.I.S.I.T.) based on ridge preservation and contour augmentation in patients with a high aesthetic risk profile: one-year results.

Abstract

To evaluate the 1-year outcome of Minimally Invasive Single Implant Treatment (M.I.S.I.T.) based on ridge preservation and contour augmentation in patients with a high aesthetic risk profile. Periodontally healthy non-smoking patients with a failing tooth in the anterior maxilla (15-25) were selected. All were in need of a single implant and demonstrated high risk for aesthetic complications given mid-facial recession at the failing tooth and/or a buccal bone dehiscence and/or a thin-scalloped gingival biotype. Patients without mid-facial recession (NRG) received flapless tooth extraction and ridge preservation using a collagen-enriched bovine-derived xenograft, flapless installation of a bone condensing implant with variable-thread design (4-6 months later), a provisional screw-retained crown and connective tissue graft (CTG) inserted in the buccal mucosa (3 months later) and a permanent crown (3 months later). Patients with mid-facial recession (RG) were treated similarly, yet they received a CTG at the time of ridge preservation. All patients were treated by an experienced periodontist using a microsurgical approach. Primary outcome variables included papillary and mid-facial recession. Clinical parameters, pink (PES) and white aesthetic score (WES) were considered secondary outcome variables. Fifty patients (25 females, 25 males; mean age 39, range 19-81; 42 in NRG and 8 in RG) met the selection criteria and consented to the treatment. Forty-seven could be examined at 12 months and all implants survived. Mean bone loss amounted to 0.48 mm (range 0.00-1.80) at 12 months. Papillary recession was minimal in both groups at 12 months (mean ≤ 0.3 mm), as was mid-facial recession in the NRG (mean 0.1 mm). Twelve patients in the NRG even demonstrated coronal migration of the mucosal margin following CTG and needed adaptation of the provisional crown to induce soft tissue retraction. Due to CTG at the time of ridge preservation in the RG, mid-facial soft tissue gain amounted to 0.9 mm at 12 months, hereby eliminating 2/3rd of the initial recession. PES and WES were favourable pointing to 10.9/14 and 8.2/10 respectively. This short-term prospective study offers a proof of principle of M.I.S.I.T. in patients with a high aesthetic risk profile.