Effect of in-office desensitizing paste containing 8% arginine and calcium carbonate and Er:YAG laser on dentinal tubules: a scanning electron microscope examination

The aim of this study was to evaluate the occluding effect of Erbium:Yttrium-Aluminum-Garnet (Er:YAG) laser and a desensitizing paste containing 8% arginine andcalcium carbonate for in-office application (Colgate® Sensitive Pro-Relief?) alone orin combination on human dentinal tubules by Scanning Electron Microscope (SEM).Fourty dentine specimens obtained from extracted impacted 3rd molars wereincluded in this study and were divided into 4 groups each containing 10 dentinespecimens. 40 specimens were processed with 1% citric acid to eliminate the smearlayer and expose dentinal tubule orifices. No treatment was applied to the dentinesamples in group I which served as the control group. Samples in group II wereirradiated with Er:YAG laser (30 hz, 60 mj/pulse, 10 seconds) and in-officedesensitizing paste containing 8% arginine-calcium carbonate was applied to thesamples in group III.In group IV, a combination of in-office desensitizing pastecontaining 8% arginine-calcium carbonate followed by Er:YAG laser was applied to thesamples. All the dentinal samples were evaluated with SEM for dentinal tubularocclusion and surface morphology.Intergroup comparisons showed that the diameters and the number of the opendentinal tubules, and a maximum number of values obtained as tubules number per100 ?m2 were observed in group I, group III, group II and group IV in decreasingorder. The results obtained in this study showed that all treatment alternatives wereable to occlude and narrow dentinal tubules. On the other hand, a more pronouncedocclusion was obtained in the combined treatment group whereas no statisticallysignificant difference was noted in the group with Er:YAG laser only and thecombined treatment group.Our results indicate that Er:YAG laser only group and the combined treatmentgroup can occlude tubules partially and totally, and therefore these treatmentmodalities may reduce patients? hypersensitivity symptoms.