Esthetic outcome and alterations of soft tissue around single implant crowns: a 2-year prospective study

Objective: The aim of this prospective study was to assess the esthetic outcome and alterations of peri-implant soft tissue using tissue-level implants. Furthermore, the influencing factors, including grafting and gingival biotype, of esthetic outcome of peri-implant soft tissue were also evaluated. Materials and methods: Of 38 patients with single missing anterior tooth in maxilla were treated with a Straumann (R) Standard Plus SLA implant. Bone augmentation was performed in 24 patients. Follow-up was conducted at 12 and 24 months after definitive crowns placement. Esthetic outcome using the pink esthetic score/white esthetic score (PES/WES) and clinical parameters were evaluated. Results: The mean PES/WES value at baseline, 1-year, and 2-year examination was 13.79, 14.87, and 14.96. Significant improvement was found between baseline and 1-year examination (P < 0.01). And the improvement between 1-year and 2-year examination was not significant (P = 0.40). The mean PES changing value in patients with thick biotype was significantly higher than those with thin biotype at 2-year after definitive crowns placement (P = 0.03). Graft procedure had an unfavorable effect on mean PES value both at baseline and at follow-up (P < 0.01). No implants were lost at 2-year examination. Three patients experienced peri-implant infection. No significant difference was found with the passage of time in modified plaque index (mPI), probing pocket depth (PPD), and modified bleeding index (mBI). Conclusion: According to the present prospective clinical study, it can be concluded that it is feasible to use tissue-level implant to support single crowns in esthetic area. Favorable short-term esthetic outcome and stability of soft tissue around single implant crowns can be expected in patients with or without graft. However, graft procedures might have an unfavorable effect on the esthetic outcome. Gingival biotype can be considered as prognostic factor for esthetic outcome. RCTs with long-term follow-up are needed to provide evidence for the long-term stability of peri-implant soft tissue using tissue-level implant systems.