Treatment outcome of two adjacent implant crowns with different implant platform designs in the aesthetic zone: a 1-year randomized clinical trial

P>Aim To evaluate the peri-implant tissues in patients with two adjacent implant crowns in the aesthetic zone, treated with either two adjacent implants with a scalloped platform or with a flat platform. Material and methods Forty patients were randomly allocated to: (1) a "scalloped implant group": 20 patients treated with two adjacent implants with a scalloped platform, and (2) a "flat implant group": 20 patients treated with two adjacent implants with a flat platform. Clinical and radiographic examinations were performed during a 1-year follow-up period to assess hard and soft tissue changes. Results The scalloped implant group showed significantly more marginal bone loss (scalloped: 2.7 +/- 1.4 mm, flat: 0.9 +/- 0.8 mm) and more inter-implant bone crest loss (scalloped: 1.8 +/- 1.4, flat: 1.0 +/- 0.9 mm) than the flat implant group. There was no significant difference between the groups with regard to the papilla index and patients' satisfaction. Conclusion After 1 year of function, there was more bone loss around scalloped implants than around flat implants. With regard to the presence of papilla, there were no differences between the groups. With both applied implant designs, it is difficult to establish a predictable and harmonious aesthetic result, especially regarding the peri-implant mucosa. Patients were very satisfied with the aesthetic outcome of the adjacent implants irrespective of the treatment concept applied.