Effects Of Nickel Ions Out From Dental Ni-Cr Metal-ceramic Alloy On Glycolysis And Ureolytic Activity Of Actinomyces Naeslundii

BackgroundDental metal-ceramic alloys including Ni-Cr alloy are wildly used in clinic nowadays. But affected by the saliva the metal ceramic alloys in the patient's mouth will release some mental ions, which may cause the gingivitis or even discoloration of the gingival tissue.However, the key of development of periodontal disease is unbalance of oral microbial populations.But there is little known about the affects of dental alloys on oral ecological balance. Early effect of Pd-Ag alloy on aerobic and microaerophilic flora from healthy oral cavity was studied. The results indicate the existence of initial inhibitory effect of Pd-Ag alloys on aerobic flora in the mouth, which might give space for anaerobic strains to increase the growth. Presence of periodontal changes in a gingival crevice with Pd-Ag alloy crowns is probably due to anaerobic micro-organisms, as mostly anaerobic strains are responsible for periodontal disease. Other studies indicate the zincions can inhabit glycolysis of human oral microbes .Actinomyces strains are found in significant numbers in both supragingival and subgingival plaque and therefore have the potential to be important contributors to total plaque ureolysis. The hydrolysis of urea by ureases of oral bacteria in dental plaque can cause a considerable increase in plaque pH, which can inhibit the development of dental caries. There is also indirect evidence that urea metabolism may promote the formation of calculus and that ammonia release from urea could exacerbate periodontaldiseases.How about the affects of nickel ions released from Ni-Cr alloy on glycolysis and ureolytic activity of Actinomyces naeslundii?ObjectiveTo investigate the effects of nickel ions on ureolytic activity and glycolysis of Actinomyces naeslundii.MethodsActinomyces naeslundii WVU45 was grown in brain heart infusion (BHI) broth with different concentration levels of nickel ions. And pH and lactate dehydrogenase(LDH) were determined. The activity of urease was mensurated.ResultsNickel ions had no significant effect on pH and the output of LDH (P>0.05 ) ,but the activity of urease was promoted by nickel ions (P<0.05) .ConclusionNickel ions could enhance the ureolytic activity of Actinomyces naeslundii, and have no significant effect on glycolysis.