Study on Occluding Effect of Er:YAG Laser Irradiation with Different Parame-ters on Human Dentinal Tubules
Objective To evaluate the occluding effect of Er:YAG laser irradiation on human dentinal tubules.Methods Complete and caries-free human premolars were selected to prepare 80 neck dentin samples,which were randomly assigned to 5 groups:blank control group,40 mJ laser irradiation group(group A),60 mJ laser irradiation group(group B),80 mJ laser irradiation group(group C)and 100 mJ laser irradiation group(group D).The laser irradiation groups were further divided by frequency of laser irradiation:1 exposure groups(group A1,B1,C1 and D1),2 exposures groups(group A2,B2,C2 and D2)and 4 exposures groups(group A4,B4,C4 and D4),12 groups in total.There were 5 sample surfaces in each group.The dentin samples of the blank control group were not treated.The dentin surface morphology of each group was observed with scanning electron microscopy(SEM).The occlusal condition of dentin tubule was analyzed with image analysis software,and the occlusal rate of dentin tubule was worked out.Results The Er:YAG laser of different parameters blocked the dentin tubule to different degrees.2 or 4 times 60-80 mJ irradiation was used to seal most of the dentin tubules,and the surface was smooth.The results of image analysis software showed that,compared with that of the blank control group and Al group,the open area of dentin tubule in other laser irradiation groups decreased more remarkably(P＜0.05).When the laser energy was 40 mJ,the occlusion rate of dentin tubule of group A1,A2 and A4 appeared a tendency of decrease(P＜0.05).Under the laser energy of 60,80 and 100 mJ,the occluding rates of dentin tubule in groups B1,Cl and D1 were significantly lower than those in group B2,C2,D2,B4,C4 and D4(P＜0.05).Conclusions The YAG laser irradiation of 60-80 mJ for 2-4 times will effectively block dentin tubules,which is a relatively appropriate dose parameter for Er:YAG laser desensitization.
NETL
NSTL
万方数据
