Does apico-coronal implant position influence peri-implant marginal bone loss? A 36-months follow-up randomized clinical trial.
Publication date: Available online 12 November 2018
Source: Journal of Oral and Maxillofacial Surgery
Author(s): Hilario Pellicer-Chover, Maria Peñarrocha-Diago, Amparo Aloy-Prosper, Luigi Canullo, Miguel Peñarrocha-Diago, David Peñarrocha-Oltra
Preserving peri-implant bone and reducing the exposure of rough implant surface might influence long-term outcomes of implant therapy. The aim of this study was to compare peri-implant clinical and radiological parameters after crestal and subcrestal dental implant placement at 36 months of follow-up.
Material and methods
A randomized clinical trial involving partially edentulous patients in need of an implant-supported, partial fixed dental prosthesis or a single crown was carried out. The patient was randomized according to the implant insertion depth: test group (implants placed approximately 2 mm below the bone crest) or control group (implants placed at bone crest level). The patients were evaluated 6, 12, 24 and 36 months after prosthetic loading. Peri-implant marginal bone loss was the primary outcome and the following secondary outcomes were registered: coronal bone changes, plaque index, probing depth, modified bleeding index, retraction and width of the peri-implant mucosa, and peri-implant health condition. Implant survival and success rates after 36 months of follow-up were calculated.
The study comprised 128 patients (83 men and 45 women – mean age 54.4±12.2 years) and a total of 265 implants (133 in the control group and 132 in the test group). There were no statistically significant differences in the peri-implant clinical parameters. After three years of follow-up, 53.4% of the crestal implants and 25.8% of the subcrestal implants presented marginal bone loss, with a mean exposed rough surface of -0.2±0.3 mm and -0.09±0.1 mm, respectively (p=0.001). The overall success rate was 99.6%.
Crestal and subcrestal implants showed similar clinical outcomes three years after prosthetic loading. Significant differences were observed in the radiological parameters, showing subcrestal implants less peri-implant marginal bone loss.