The effect of triangular cross‐section neck design on crestal bone stability in the anterior mandible: A retrospective study with a 5‐year follow‐up

Abstract

AbstractObjectivesThe objective of this study, which included a 5‐year follow‐up, was to compare peri‐implant soft tissue health, crestal bone loss (CBL), and buccal bone thickness (BBT) around triangular cross‐section neck (TN) or round neck (RN) implants, using cone‐beam computed tomography.Materials and MethodsThis study was initially designed as a prospective 1‐year randomized controlled study and then extended with a 5‐year retrospective evaluation of clinical and radiographic records. In the initial 1‐year study, a total of 20edentulous patients receiving 40 implants with similar diameters were randomly assigned to the RN or TN groups using a split‐mouth design. Pocket probing depths (PPD), plaque index (PI), and gingival index (GI) were recorded at postoperative month 12. CBL and BBT at three levels (0, −2, and −4 mm) were evaluated 1 year after insertion. Five years after insertion, PPD, PI, GI, CBL, and BBT were recorded as patients were recalled for clinical and radiographic monitoring.ResultsNineteen patients completed the study. After 5 years, no significant differences in PPD, PI, and GI scores and BBT values between the two groups (p > .05). The mean ± SD CBL values at the final follow‐up visit were −0.71 ± 0.69 mm for TN and −1.03 ± 0.86 mm for RN (p < .01).ConclusionsThese results suggest better crestal bone preservation using implants with TN when compared to RN after a 5‐year follow‐up. However, TN showed similar results to RN regarding peri‐implant soft tissue health and BBT.