Effects Of Lemon Essential Oil On Caries Development In Rats

Objective:Dental caries is one of the disease which affect the health of humans,but now there have no kind of ideal drugs to prevent dental caries. In recent years, natural medicine research to prevent dental caries is getting more and more attention by scholars. Our team was the first at home and abroad to carry out the series of research about Lemon essential oil dealing with dental caries.We find out that Lemon essential oil have the effects of antibacterial in causing caries.Bellow the MIC,it has the effects of inhibit bacteria early adhesion, acid yield, yield extracellular polysaccharide, and other caries virulence factors. The experiment based on the previous studies, use caries rats models in the real biological environment,to evaluate the prevent cavities efficiency of the Lemon essential oil and it’s primary components of limonene objectivly.Methods:1. The LEO and composition analysis:Use the Water-steam distillation extract the essential oil,measurement LEO components chromatogram-mass spectrogram total ion current chromatogram (TIC) in a given GC-MS. According to the search NIST2008spectral library, by peak area normalization method for quantitative analysis of the various components and evaluate of the relative content.2. LEO and its main component LIM control dental caries animal experimental study(1) Create rats caries disease model:The Wiste rats, Male and female half and half, fed Keyes2000#and5%surose in drinking water until the end of this experiment.(2) The experiment group, positive control group:0.12%CXH; The experimental group:4.50mg/mL LEO group,10.50mg/mL1IM group; negative group:distilled water.(3) The experiment process:after inoculation S. sobrinus, treatments rat with different drugs,for5weeks, twice a day. At the end of the experiment, acquisition saliva of the rats, dilution and coated plate. Finally, ether anesthesia rats to death, prepare jaw bone specimen. (4) Observe index:Use the S.sobrinus level, Keyes scores, DIAGNOdent as the index to evaluate the effect of dental caries prevention drugs.Results:(1) From the the lemon GC-MS total ion chromatogram (TIC), were detected in more than100peaks were identified, of which40peaks accounted for93.95percent of the total volatile oil content. The main ingredient is the limonene.(2) The MIC of LEO、LIM to s.sobrinus: The MIC of LEO to s.sobrinus is4.50mg/mL The MIC of LIM to s.sobrinus is21.00mg/mL.(3) S. sobrinus level:at the end of experiment, compare with the negative control group, two experimental groups and positive control group,total CFU,both S.sobrinus and S.sobrinus ratio decline differ to the extent. Only S.sobrinus CFU had statistical significance(P<0.05), Compared to the positive group, the two experimental groups and the negative control group total CFU、S.sobrinus CFU and S.sobrinus ratio all has statistical significance(P<0.05); Compared between groups, LEO,LIM total CFU、S.sobrinus CFU and S.sobrinus ratio has no statistical significance (P>0.05)(4) Keyes scores:in the smooth surface caries, two experimental groups and positive control group are displayed inbibitional effect in rat caries extent and caries numbers compared to the negative group, and has statistical significance(P<0.05), Positive groups there was no statistically significant difference compared with LEO (P>0.05); Positive control compared with LIM group, the difference was statistically significant (P<0.05). LEO group compared with LIM group, there was no statistically significant difference (P>0.05); In the pit and fissure caries, compared to the negative group, two experimental groups and positive control group are displayed keyes scores reduction at different degrees, and has statistical significance (P<0.05) At different grades carries,LEO has a lower scores compared to LIM but has no statistical significance(P>0.05).(5). DIAGNOdent indication:In the smooth surface caries diagnosis, compared to the positive control group,experimental groups displayed the indication increase, and has statistical significance(P<0.05).LIM has a higher indication compared to LEO,but has no statistical significance((P>0.05).Compared to the negative group,two experimental groups and positive control group are displayed lower indication and has statistical significance(P<0.05).Conclusions:1. LEO extracted by steam distillation, Terpene compounds are the main component, account for78.85%of the total content.2. LEO, LIM has inbibitional effect on cariogenic bacteria S.sobrinus.3. In rat model of caries disease, LEO, LIM does not affect oral microecological balance.4. In rat model of caries disease,LEO and LIM has inbibitional effects on smooth surface caries and pit and fissure caries under MIC concentration.But LEO has a more better effect. We infer that there have some more effective components in LEO,or the components in LEO has synergistic effect.