In vitro study of dentin hypersensitivity treated with Nd:YAG laser / 西安交通大学学报(医学版)

ABSTRACT

ABSTRACTObjective To observe the structural changes of dentin irradiated with NdYAG laser under dif-ferent parameters and the changes of calcium-phosphorus ration,and evaluate the optimal parameters of NdYAG laser in treating dentin hypersensitivity (DH).Methods The model of dentin hypersensitivity was established by acid etching method.Samples were irradiated with NdYAG laser under different parameters.The morphological alterations of the dentin surfaces and Ca-P ratio were examined with scanning electron microscopy (SEM)combined with energy dispersive X-ray microanalysis.Results Compared with those in the control group,dentinal tubules could be blocked partially or totally with no cracks in A-C (30 mj,5 Hz),(30 mj,10 Hz)and (50 mj,5 Hz)groups. Dentinal tubules could be entirely blocked but with cracks in D (50 mj,10 Hz)and E (80 mj,5 Hz)groups.Dentin was carbonized in F (80 mj,10 Hz)group.Compared with that in the control group,Ca-P ratio was decreased sig-nificantly (P <0.05).Conclusion The suitable energy parameter of NdYAG laser in treating dentin hypersensi-tivity is (30 mj,10 Hz)and (50 mj,5 Hz).