Decontamination process affects negatively the adhesion of osteoblastic cells on implant surface

7JN0L ePOSTER BASIC RESEARCH

Background: The colonization, structure and bacterial biofilm on implant surfaces is influenced by implant surface roughness, chemical composition, hydrophobic properties, surface electrical charge and energy. Moderate rough implants show higher rates of re-osseointegration when compared to maCHINAd ones. Decontamination with different solutions was unable to completely decontaminate implant surfaces and could induce changes in the chemical and physical properties, with partial re-osseointegration.

Aim/Hypothesis: The aim of this study is to investigate the behavior of osteoblastic cells in different moderate rough implants on decontaminated vs. uncontaminated surface.

Materials and Methods: Five types of implants with different macro and microstructure were investigated in this study: NaNOite (NT)/Biomet 3i; Osseotite (OT)/Biomet 3i; SLActive (SLA)/Straumann; Acqua (ACQ)/Neodent; Drive Neoporos (CM)/Neodent. The chemical-physical characteristics were investigated through surface chemical composition by energy disperses x-ray detector and wettability properties. Implants were contaminated by Aggregatibacter actinomycetemcomitans and decontaminated by different protocols: chlorhexidine, citric acid associated with EDTA and antimicrobial photodynamic therapy. After that, implants were investigated for adhesion (24 hours) or proliferation (72 hours) of osteoblastic cells (Saos-2) into two groups; experimental group (n = 15/type of implant; decontaminated implants) or control group (n = 5/type of implant; pristine implants). Scanning electron microscopy images were evaluated through Image J software.

Results: ACQ was found to be highly hydrophilic and NT was the most hydrophobic implant. NT and CM implants were composed by titanium pure when compared with ACQ, SLA and OT that showed others chemical compositions. Increased variation of Saos-2 cells adhesion and proliferation was observed on all experimental and control groups. Only CM type of implant showed statistic difference significant when compared areas uncontaminated and decontaminated in 24 hours (P = 0.0498; Tukey's multiple comparisons test). Controversially, in proliferation analysis in 72 hours, CM implant was the only implant that showed no significant difference between test and group (P = 0.2833; Tukey's multiple comparisons test). NT type showed the greater value of proliferation cells when compared with all types of implant surface (P = 0.0002; Tukey's multiple comparisons test).

Conclusions and Clinical Implications: All experimental groups (decontaminated implants) showed lesser cells attached on implant surface during 24 hours and 72 hours, adhesion and proliferation analysis, respectively, when compared to control group (uncontaminated implants). These findings suggest that decontamination surface were able to impair the counting of adhesion and proliferation cells, considering that re-osseointegration is difficult to obtain when the implant surface had bacteria presence and decontamination residual.

Acknowledgements: CAPES: Coordination for the Improvement of Higher Education Personnel.

Keywords: dental implants, implant surface, decontamination, osteoblasts, implant surface