Soft tissue cell adhesion to titanium abutments after different cleaning procedures: preliminary results of a randomized clinical trial.

OBJECTIVES: A randomized controlled trial was performed to assess soft tissue cell adhesion to implant titanium abutments subjected to different cleaning procedures and test if plasma cleaning can enhance cell adhesion at an early healing time. STUDY DESIGN: Eighteen patients with osseointegrated and submerged implants were included. Before re-opening, 18 abutments were divided in 3 groups corresponding to different clinical conditions with different cleaning processes: no treatment (G1), laboratory customization and cleaning by steam (G2), cleaning by plasma of Argon (G3). Abutments were removed after 1 week and scanning electron microscopy was used to analyze cell adhesion to the abutment surface quantitatively (percentage of area occupied by cells) and qualitatively (aspect of adhered cells and presence of contaminants). RESULTS: Mean percentages of area occupied by cells were 17.6 ± 22.7%, 16.5 ± 12.9% and 46.3 ± 27.9% for G1, G2 and G3 respectively. Differences were statistically significant between G1 and G3 (p=0.030), close to significance between G2 and G3 (p=0.056), and non-significant between G1 and G2 (p=0.530). The proportion of samples presenting adhered cells was homogeneous among the 3 groups (p-valor = 1.000). In all cases cells presented a flattened aspect; in 2 cases cells were less efficiently adhered and in 1 case cells presented filipodia. Three cases showed contamination with cocobacteria. CONCLUSIONS: Within the limits of the present study, plasma of Argon may enhance cell adhesion to titanium abutments, even at the early stage of soft tissue healing. Further studies with greater samples are necessary to confirm these findings.

Systemic risk factors for peri-implant bone loss: a systematic review and meta-analysis.

The aim of this study was to determine the influence of patient-related systemic risk factors (systemic disease, genetic traits, chronic drug or alcohol consumption, and smoking status) on peri-implant bone loss at least 1 year after implant installation and prosthetic loading. An electronic search was performed of MEDLINE, EMBASE, and The Cochrane Central Register of Controlled Trials up to January 2012. One thousand seven hundred and sixty-three studies were identified. After applying a three-stage screening process, 17 articles were included in the qualitative analysis, but only 13 in the quantitative analysis, since smoking was a common exposure. The meta-analysis of these 13 studies (478 smokers and 1207 non-smokers) revealed a high level of heterogeneity and that smoking increases the annual rate of bone loss by 0.164 mm/year. Exposure to smoking had a harmful effect on peri-implant bone loss. However, the level of evidence for oral implant therapy in patients with systemic conditions is very low. Future studies should be improved in order to provide more robust data for clinical application.