Influence of crestal and sub-crestal implant position on development of peri-implant diseases: a 5-year retrospective analysis.

ABSTRACT

OBJECTIVES: The aim of the present study was to evaluate the influence of crestal and subcrestal implant position on development of peri-implant diseases. MATERIALS AND METHODS: The study was designed as a retrospective clinical and radiographic analysis. Implant-supported fixed dental prostheses were allocated in two groups with the shoulder (i) placed in sub-crestal level and (ii) placed at bone level. For each patient, the following clinical variables were assessed FMPS, FMBS, PlI, BOP, and PD. After prothesis delivery, an intraoral radiograph was obtained; this exam was performed also at 5 years of observation period. RESULTS: No statistically significant difference was found in terms of FMPS and FMBS at baseline and after 5 years follow-up (P < 0.05). A statistically significant difference was assessed between PD of control group and test group (P = 0.042). Patient-based analysis showed a 25.6% of peri-implant mucositis and 32.6% of peri-implantitis for implants placed with the shoulder in crestal position, while for implants inserted in sub-crestal position the percentage of peri-implant-mucositis and peri-implantitis were 19%; no statistically significant difference was found between groups after 5 years (P < 0.05). CONCLUSIONS: Within the limitation of the present study, the clinical and radiographic outcomes showed that the percentage of peri-implant mucositis and peri-implantitis was not statistically significant for both groups after 5 years follow-up. CLINICAL RELEVANCE The outcomes of present study clinically demonstrated that a deep position of implant shoulder did not provide any benefits. On the contrary, it may be considered a possible risk indicator for implant diseases.