Objective:To observe the inhibition of Chinese gallnut on bacteria in plaque biofilms by the use of artificial mouth.Methods:Water extract of Chinese Gallnut was prepared and liquid media two-fold dilution method was used to determine the minimal inhibition concentration(MIC)of the drug on S.mutans,A.viscosus,S.sanguis and S.oralis.Individual bacteria plaque biofilms in artificial mouth were created.The inhibition of Chinese gallnut on the bacteria in plaque biofilms was studied by colony counting.Results:In bacteria suspension gallnut water extract inhibited the growth of the four kinds of bacteria.The MIC of the extract on S.mutans,A.viscous and S.sanguis was 64 mg/ml,that on S.oralis 8 mg/ml.The plaque biofilms formed by the four kinds of bacteria could be inhibited by 2 mg/ml-128 mg/ml of the extract dose-dependently.At the highest tested conentration(128 mg/ml)the gallnut water extract could not completely clear up the colonyforming unite(CFU)of the becteria.Conclusion:Chinese gallnut water extract can inhibit the growth of bacteria in suspension and in plaque biofilms,the bacteria in biofilms may have stronger resistance to the extract.

Irrigation is one of the most important steps of root canal preparation. This study evaluated the dentin micro-hardness changes irrigated by Chinese nutgall solution and other irrigants, and investigated the influence of each irrigant on root canal dentin hardness. The results showed that all kinds of solution decreased the micro-hardness of root canal dentine. Chinese nutgall solution group did not significantly decrease the dentine micro-hardness with concentration increased over time.

Objective: To observe the effects of Chinese nutgalls ex tr acts on the secretion of IL-6 from monocytes induced by lipopolysaccharide (LPS ) of Porphyromonas gingivalis (Pg). Methods:Monocytes ob tained by separating human blood cells were stimulated with LPS of Pg at 25 ?g/ml, radioimmunoassay (RIA) was used to examine the effect of Chinese nutgal ls extracts at the concentrations of 6.25-100 ?g/ml on the secretion of IL-6 in the supernatant of the cell culture. Results:Chinese nutgalls extracts at the concentrations(?g/ml) of 6.25,12.50, 25.00 ,50.00 and 100.00 inhibited IL-6 secretion from monocytes by(%) 34.6,46.4,48.5,52.7 and 54.9 res pectively.Conclusions:Extracts from Chinese nutgalls may inhibit the secretion of IL-6 from monocyte induced by LPS of Pg in a dose-depend ent manner.

Objective:To observe the effects of gallnut water extract on the vitality of plaque biofilms.Methods:The oral plaque biofilms were obtained through bonding the enamel fragments to the bucca of the mindibular first molar for 24 h.The two groups of the biofilms were treated by gallnut water extract at 6 mg/ml and saline(control) for three minutes respectively.The effect of gallnut water extract on the vitality of plaque biofilms was observed by Ethidium bromide/Fluorescein diacetate (EB/FDA) staining and confocal laser scan microscope(CLSM).Results:All specimens had early biofilm formed,The percent vitality of the plaque biofilms treated with gallnut water extract and the control was 37.10?9.63 and 60.78?7.60 respectively(P