Marginal Bone Levels and Soft Tissue Conditions Around Single-Tooth Implants with a Scalloped Neck Design: Results of a Prospective 3-Year Study

Abstract

Scalloped implants were developed to better maintain marginal bone. Therefore, this study evaluated marginal bone levels (MBLs) and soft tissue around single implants with scalloped necks in the esthetic zone prospectively over a 3-year period. MBLs were compared to those of conventional flat-platform implants at 1 and 3 years. Patients received anterior single-tooth implants and were divided into two groups; the test group included implants with a scalloped neck design and the control group included conventional rough-surface implants with external hex. MBLs were compared radiographically at 1 and 3 years after crown insertion. For the test group, soft and hard tissue assessments were made at six different time points, beginning at abutment connection. Mesial and distal interproximal papillae and probing depths were assessed clinically. Data were analyzed with the Student t test and repeated measures analysis of variance on ranks (P < .05). Twenty-four patients (17 men, 7 women) took part; each group included 12 implants. The test group had significantly more marginal bone resorption than the control group at each time point (P < .001). With respect to changes in MBL values over time, a significant difference was detected between groups mesially (P < .001) but not distally. Statistical analyses demonstrated obvious significant increases with time (P < .001) in bone resorption and mesial papilla index. A significant increase over time in probing depths was demonstrated distally (P = .003) but not mesially. The scalloped implant did not stabilize interproximal bone remodeling and caused more bone loss than conventional implants. Soft tissue levels were not maintained around the scalloped implants.