The Mineralization Al Effect Of Lemon Essential Oil And Other Natural Products On Tooth In Vitro

Objective:Caries is a disease of chronic progressive, a dynamic processes which occur chemical demineralization and remineralization alternately. If the whole process of remineralization dominated, demineralization area were repaired.Our group lead in series of studies about lemon extract in2004.The main ingredient is limonene (LIM) and we found that they can inhibit common oral cariogenic bacteria, early adhesion, acid production and polysaccharide cariogenic virulence factors production.Tea polyphenol(TP) and Chlorhexidine (CHX) is antimicrobial agent.The research aims to evaluate the effectiveness of LEO、LIM、TP and CHX of dental caries from the perspective of the mineralization and to evaluate whether the synergistic effect with NaF, providing a theoretical basis for natural product research.Methods:1.Sample preparation of artificial caries:Prepare enamel and root dentin samples with bovine incisors, placed in demineralization solution for96hours to form artificial caries specimens.2.The experiment group:Negative control; Positive control:1mg/ml NaF; Experimental groups:4.5mg/mlLEO;4.5mg/mlLEO+lmg/mlNaF;21mg/mlLIM;21mg/mLIM+lmg/ml NaF;2mg/ml TP;2mg/ml TP+1mg/ml NaF;2mg/mlCHX.3.pH cycling experiment Each group of samples were immersed in demineralization solution14h, test solution2h and remineralization solution8h at37℃.Each two have ultrasonic vibration in a buffer solution5min before treatment. The whole pH cycle lasted8days.Observation indexes:Use the release value of calcium, phosphorus ions the surface of a sample of calcium and phosphorus atom percentage and ratio of calcium and phosphorus the surface microhardness recovery value and hydroxyproline concentration as the index to evaluate the effect of mineralization.Results:1.The release value of calcium, phosphorus ions in demineralization solution Enamel: LEO, LIM, TP and CHX compared with the negative control group (P>0.05). Dentin: LEO group of calcium release value was lower than control group(P <0.05);calcium, phosphorus ions:LIM, TP and CHX groups compared with the negative control group, the difference was not statistically significant (P>0.05).2.Surface microhardness:LEO, LIM, TP and CHX groups of enamel and dentin specimen compared with the negative control group, the difference was not statistically significant (P>0.05).3. Ca/P:Enamel:LIM, TP and CHX were higher than the negative control group (P<0.05); LEO group compared with the negative control group, the difference was not statistically significant (P>0.05). Dentin:LEO, LIM, TP and CHX were higher than that of the negative control group, the difference was statistically significant (P<0.05).4.Hydroxyproline concentration in remineralization solution:LEO, LIM and CHX group were lower than the negative control group(P<0.05); TP group compared with the control group, the difference was not statistically significant (P>0.05).5.Combined with NaF:We haven’t found that the combined application of each experimental group and NaF have a synergistic effect(P>0.05).Conclusions:1. LIM, TP and CHX can promote remineralization in bovine enamel;2. LEO has the inhibitory effect of dentin demineralization;3. LEO, LIM, TP and CHX can promote dentin remineralization;4. LEO, LIM and CHX have the inhibitory effect of collagen matrix degradation;5. LEO, LIM, TP and CHX found no inhibitory effect of enamel demineralization;6. LEO, LIM combined with NaF were not found the synergistic effect.7. Compared with the surface microhardness testing, spectral analysis is a more sensitive indicator of the mineralization.