Effect of Anti-infective Mechanical Therapy on Clinical Parameters and Cytokine Levels in Human Peri-implant Diseases

Background: The objectives of this study were to clinically and immunologically assess the effects of mechanical anti-infective therapies for mucositis and peri-implantitis and to compare the levels of cytokines in untreated and treated peri-implant diseased sites to healthy ones.

Methods: Titanium dental implants were assigned to one of the following groups: healthy (n = 10) = control; mucositis (n = 10) = mechanical debridement using abrasive sodium carbonate air-powder and resin curets; and peri-implantitis (n = 20) = open surgical debridement using abrasive sodium carbonate air-powder and resin curets. Visible plaque accumulation, marginal bleeding, bleeding on probing, suppuration, and probing depth were assessed at baseline for all groups and at 3 months after therapies for diseased groups. At these times, the total amounts of interleukin (IL)-4, -10, and -12, tumor necrosis factor-alpha (TNF-alpha), receptor activator of nuclear factor-kappa B ligand (RANKL), and osteoprotegerin (OPG) in the peri-implant crevicular fluid (PICF) were measured by enzyme-linked immunosorbent assay.

Results: At 3 months, the anti-infective treatments resulted in a significant improvement in all clinical parameters for mucositis and peri-implantitis (P <0.05). Moreover, the total amounts of TNF-alpha in PICF were significantly higher in untreated diseased implants compared to healthy ones, and the OPG/RANKL ratio was higher for healthy implants than for untreated peri-implantitis (P <0.05). TNF-alpha levels were significantly reduced for both diseased groups (P <0.05), achieving the same level as the healthy group at 3 months after therapies (P >0.05).

Conclusion: The proposed anti-infective therapies may locally modulate the levels of TNF-alpha and the OPG/RANKL ratio and improve clinical parameters around peri-implant tissues.