A Comparative Study Of Er,Cr:YSGG Laser And Duraphat On Acid Resistance And Remineralization Of Enamel

Objective:Dental caries refers to a chronic disease caused by inorganic demineralization and decomposition of organic matter caused by acid production of certain bacteria,which causes the destruction of dental hard tissue.If not diagnosed and treated in time,it will gradually develop into pulp and periapical diseases,which will reduce the quality of life.Therefore,early prevention and treatment of dental caries is particularly important.Enhancing the acid resistance of enamel and re-mineralizing early demineralized enamel by some methods are of great significance for the treatment of dental caries.Er,Cr:YSGG laser has been widely recognized since 1998 when it was first licensed by the Food and Drug Administration of the United States.Nowadays,it is widely used in oral in vitro experiments and clinical treatment.CO₂ laser,argon laser,Nd:YAG laser and other lasers have been proved to enhance the anti-caries ability of enamel.However,whether Er,Cr:YSGG laser can enhance the anti-caries ability of enamel,whether there is difference in the anti-acid and re-mineralization ability between Er,Cr:YSGG laser and Duraphat,which is the most commonly used anti-caries drug in clinic,is still unknown.In this study,Er,Cr:YSGG laser was used to irradiate the face of the teeth to compare the local use of Duraphat.The anti-caries effect of the laser caries detection pen?DIAGNOdent pen?was evaluated in vitro.The results provide theoretical basis for Er,Cr:YSGG laser in anti-caries of enamel.Methods:Experiment 1.?1?48 fresh extracted premolars were selected for orthodontic reduction.The specimens were randomly divided into four groups,12 in each group.?2?Anti-acid experiment:DIAGNOdent was used to detect the initial values?DD values?of each group before operation,but the control group was not treated.In the experimental group 1³,laser irradiation was applied to the enamel surface,Duraphat coating,laser irradiation combined with Duraphat coating respectively;all specimens were put into demineralization solution for 7 days;after 7 days,the experiment stopped,DD values were recorded and analyzed statistically.Experiment 2.?1?50 fresh extracted premolars were selected for orthodontic reduction.Two samples were randomly selected as original samples.The remaining samples were randomly divided into four groups,12 in each group.?2?Demineralization:all specimens were put into the demineralization solution for 24 hours,then stopped demineralization after 9days,and recorded the DD value after demineralization;?3?Remineralization experiment:the control group was not treated,the experimental group 1³ was laser irradiated enamel surface,Duraphat coating,laser irradiation combined with Duraphat coating;all specimens were put into the prepared artificial saliva,and the samples were taken out 72 hours later,After drying,the DD values after remineralization were measured and analyzed statistically;Two samples were randomly selected from each group and scanned under electron microscope.Results:Experiment 1 After demineralization,the DD values of the experimental groups decreased compared with the control group,with statistical significance?P<0.05?;there was no significant difference in DD values between the laser group and the Duraphat group?P>0.05?;the DD values of the laser combined with Duraphat group were the smallest after demineralization,with statistical significance?P<0.05?.Experiment 2.After remineralization,the DD values of each group decreased,except for the control group before and after remineralization without statistical difference?P>0.05?,the other three experimental groups before and after remineralization had statistical significance?P<0.05?;The DD values after remineralization from small to large were:laser combined with dolefluoride group,laser group,control group,the difference was statistically significant?P<0.05?;under electron microscopy,the control group was not clear.The enamel surface of the laser group was damaged,and the other two groups showed remineralization.Conclusion:?1?Er,Cr:YSGG laser can enhance the acid resistance of enamel at a certain power,and there is no statistical difference between Er,Cr:YSGG laser and Duraphat alone.?2?Er,Cr:YSGG laser combined with dolefluoride at a certain power can play a synergistic role in the acid resistance of enamel.?3?There is insufficient evidence for the remineralization of demineralized enamel by Er,Cr:YSGG laser alone.It is suggested that the parameters of Er,Cr:YSGG laser should be adjusted later for further study.?4?At a certain power,Er,Cr:YSGG laser combined with dolefluoride can enhance the effect of dolefluoride in early demineralized enamel remineralization.