David Schneider1, Lukas Witt1, Christoph H F Hämmerle1. 1. Center for Dental and Oral Medicine and Cranio-Maxillofacial Surgery, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, University of Zurich, Zurich, SwitzerlandCenter for Dental and Oral Medicine and Cranio-Maxillofacial Surgery, University of Zurich, Zurich, Switzerland.
Abstract
PURPOSE: The aim of this study was to investigate the influence of the crown-to-implant length ratio (c/i ratio) on the implant survival, changes of the marginal bone level (MBL) and the occurrence of biological and technical complications. MATERIAL AND METHODS: This cross-sectional retrospective study included all patients with implants in the posterior segments supporting single crown restorations with a minimum follow-up of 5 years. All patients were questioned and examined clinically and radiographically. The technical and biological c/i ratio and the MBL were measured on digitized periapical radiographs. The following outcome parameters in relation to the c/i ratio and the co-factors were statistically analyzed: implant survival rate, MBL, occurrence of technical and biological complications. For statistical analysis, regression, correlation and survival analyses were applied (P<0.05). RESULTS: Seventy patients (mean age of 50.7 years [range 19.8-76.6 years]) with a total of 100 implants (24 Straumann type, 76 Brånemark type) were included in this study. The mean follow-up period was 6.2 years (range 4.73-11.7 years). Six implants failed during the follow-up period, yielding a cumulative survival rate of 95.8% at 5 years in function. The mean technical c/i ratio was 1.04 (±0.26, range 0.59-2.01). The mean biological c/i ratio was 1.48 (±0.42, range 0.82-3.24). No statistically significant influence of the technical and biological c/i ratio was found on the implant survival, MBL and occurrence of technical and biological complications. When adjusted for the biological c/i ratio, smoking was the only co-factor significantly associated with implant failure and biological complications. CONCLUSION: In the present study, the c/i ratio did not influence the clinical performance of implants supporting single crown restorations in the posterior segments of the jaw within the range tested.
PURPOSE: The aim of this study was to investigate the influence of the crown-to-implant length ratio (c/i ratio) on the implant survival, changes of the marginal bone level (MBL) and the occurrence of biological and technical complications. MATERIAL AND METHODS: This cross-sectional retrospective study included all patients with implants in the posterior segments supporting single crown restorations with a minimum follow-up of 5 years. All patients were questioned and examined clinically and radiographically. The technical and biological c/i ratio and the MBL were measured on digitized periapical radiographs. The following outcome parameters in relation to the c/i ratio and the co-factors were statistically analyzed: implant survival rate, MBL, occurrence of technical and biological complications. For statistical analysis, regression, correlation and survival analyses were applied (P<0.05). RESULTS: Seventy patients (mean age of 50.7 years [range 19.8-76.6 years]) with a total of 100 implants (24 Straumann type, 76 Brånemark type) were included in this study. The mean follow-up period was 6.2 years (range 4.73-11.7 years). Six implants failed during the follow-up period, yielding a cumulative survival rate of 95.8% at 5 years in function. The mean technical c/i ratio was 1.04 (±0.26, range 0.59-2.01). The mean biological c/i ratio was 1.48 (±0.42, range 0.82-3.24). No statistically significant influence of the technical and biological c/i ratio was found on the implant survival, MBL and occurrence of technical and biological complications. When adjusted for the biological c/i ratio, smoking was the only co-factor significantly associated with implant failure and biological complications. CONCLUSION: In the present study, the c/i ratio did not influence the clinical performance of implants supporting single crown restorations in the posterior segments of the jaw within the range tested.
Authors: Douglas R Monteiro; Emily V F Silva; Eduardo P Pellizzer; Osvaldo Magro Filho; Marcelo C Goiato Journal: World J Clin Cases Date: 2015-01-16 Impact factor: 1.337
Authors: Jakub Hadzik; Maciej Krawiec; Konstanty Sławecki; Christiane Kunert-Keil; Marzena Dominiak; Tomasz Gedrange Journal: Biomed Res Int Date: 2018-05-16 Impact factor: 3.411