Adhesion Of Porphyromonas Gingivalis On Various Dental Implant Abutment Materials In Vitro

Objective: The study is to compare the porphyromonas gingivalis adhesion on 5different abutment materials under saliva-within culture or saliva-without culture. By analyzing the adhesion amount of porphyromonas gingivalis on 5 different abutment materials, we may provide a better guidance when selecting abutment materials in clinical practice.Methods:All samples, including pure titanium(Ti), zirconium oxide(Zr), cobalt chromium alloy(Cc),cast ceramics(Cz), titanium alloy(Al), were grinded and polished by silicon carbide sandpapers in same size. The atomic force microscopy(AFM) were used to observe the morphology of the surface of different materials, and the detection of surface roughness. Use contact angle to measure instrument detection of surface wettability. After ultrasonic cleaning and high-pressure steam sterilization,put the specimens into the P.g bacterium suspension, anaerobic culture for 4 hours in37℃.Then use MTT assay to detect the absorbance value of P.g on the specimens of each group, use plate count method to calculate the colony forming units(CFU/ml) of the bacterium solution. All data were processed by SPSS19.0 statistical software.Results:(1)Using one-way ANOVA to analyse the surface roughness values(Ra) of the 5group samples, results showed that the values of the 5 groups had no significant statistical differences(P>0.05).(2)Using one-way ANOVA to analyse the surface contact angle of the 5 groups,the results were the same when saliva-within culture or saliva-without culture showed that 5 groups of different materials’ surface contact angle had statistical differences(P<0.01).(3)Under saliva-without culture, both MTT assay showed: significant differences between Ti with Cc and with Cz group(P<0.01), Zr with Cc and with Cz group(P<0.01).Under saliva-without culture, plate count method showed:significant differences between Zr group with Cz group(P<0.01),.(4)Under saliva-within culture, both MTT assay and plate count method showed:statistical differences between Ti group and Cc group(P<0.05), significant differences between Zr group and Cc group(P<0.01).(5) Same material under different environmental conditions, the amount of P.g adhesion was more when saliva-within, compared to saliva-without, but no statistically differences(P>0.05).Conclusions:(1)In vitro early adherence of porphyromonas gingivalis to the Cc surface was significantly greater than Ti, Zr. The anti-P.g early adhesion activity of Ti and Zr was better than Cc.(2)The early adherence of the porphyromonas gingivalis on Zr was similar to that on Ti in vitro.(3)Artifical saliva didn’t influence the early adherence of porphyromonas gingivalis to the same abutment surfaces in vitro.