Changes in Inflammatory Mediators in Peri-Implant Fluid After Implant Insertion

Background: Endosseous dental titanium implants have revolutionized restorative dentistry and have made a significant impact on improved patient care. The aim of this study was to compare and evaluate the influence of the placement technique on periodontal health. Methods: A baseline examination was performed in patients with submerged and non-submerged titanium implants, including an evaluation of plaque index (PI), gingival index (GI), periodontal probing depth (PD), clinical attachment level (CAL), and bone level, as well as histamine and arachidonic acid metabolite concentrations, in the peri-implant: crevicular fluid. Examinations were repeated after 12, 24, and 36 months. Results: Bone loss was significantly higher in the submerged group relative to the non-submerged group at 3 years (P<0.01), with a slight increase at 24 months. All clinical parameters were significantly higher in the submerged group relative to the non-submerged group at 24 and 36 months (P <0.05 for PI; P<0.01 for GI, PD, and CAL). The mean levels of histamine and other inflammatory mediators were significantly higher, whereas 15(S)-hydroxy-5,8,11,13-eicosatetraenoic acid concentrations were significantly reduced in the submerged group, with a high correlation with periodontal indices at 24 and 36 months (P<0.001). Conclusion: This longitudinal study suggested that submerged implants present a number of risks for periodontal complications compared to non-submerged implants, which can be evidenced by inflammatory mediator variations in the peri-implant crevicular fluid. J Periodontol 2009;80:297-306.