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.

Differential cytokine expressions affect the severity of peri-implant disease.

OBJECTIVE: This study assessed gene expression by quantitative polymerase chain reaction of inflammatory- [interleukin (IL)-12, tumor necrosis factor-alpha (TNF-alpha), IL-4, and IL-10] and osteoclastogenesis-related factors [receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG)] in sites exhibiting different severities of peri-implant disease. MATERIAL AND METHODS: Peri-implant soft tissue biopsies (n=48) were harvested from healthy implant (HI), mucositis (MC), initial peri-implantitis (IP) and severe peri-implantitis (SP) sites. RESULTS: IL-12 and TNF-alpha mRNA levels were higher in SP, followed by IP and MC (P <0.05). IL-4 was higher in HI, followed by MC, SP and IP (P <0.05). IL-10 was the lowest in HI, while no differences were detected among the diseased groups (P>0.05). OPG mRNA levels were higher in HI, followed by IP, SP and MC, whereas RANKL was increased as the peri-implantitis severity increased (P<0.05). The highest OPG/RANKL ratio was observed in HI and the lowest in SP (P<0.01). CONCLUSION: These findings suggest that expressions of inflammatory- and osteoclastogenesis-related factors may play an important role in the onset and severity of the peri-implant diseases.