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[Effects of tobacco on rat gingival fibroblats attaching to titanium].

PURPOSE
The study was designed to observe the effects of the smokeless tobacco extract(ST) on the attachment,morphology,structure and proliferation of rat gingival fibroblasts(RGFs) to titanium in vitro.


METHODS
RGFs were obtained from explants of rat normal gingival tissues by using tissue-explant technique.The origin of cells was identified by immunochemistry of vimentin and cytokeratin. RGFs to titanium were cultured in the presence of ST at various concentration,the attachment and growth of cells attached to titanium were measured by MTT method, immunofluorescence was used to detect and analyze the shapes of RGFs attached to titanium.Statistical analysis was performed using SPSS13.0 software package for one-way ANOVA.


RESULTS
Immunochemical study showed that vimentin was expressed in RGFs while cytokeratin was negative,which indicated that RGFs were originated from mesoblastoma.With the increasing of ST concentration,the attachment,spreading shape and proliferation of RGFs in all groups decreased in a concentration-dependent manner.The difference between ST group and control group was statistically significant(P<0.05).


CONCLUSIONS
ST can inhibit the attachment,spreading shape and proliferation of RGFs, suggesting that smoking may have influence on the long result of oral implant operation.