Evaluation of the Effects of Different Desensitizing Agents and Lasers and Their Combinations on Human Dentine Tubules: An In-vitro Analysis

Objectives: Treatment of dentinal hypersensitivity by occluding exposed dentinal tubules is achieved by several materials and methods. Various treatment modalities have been proposed for dentin hypersensitivity, but to date, no single agent or form of treatment has been found effective.The aim of this study is to evaluate the in vitro effects of different office type desensitizing agents and different kind of laser alone or in combination with together on human dentine tubules by using scanning electron microscopic (SEM) and Atomic Force Microscopy (AFM) analysis.
Methods: Eighty four dentine specimens obtained from freshly extracted impacted third molars were included and divided into seven groups. Group 1 (Control), Group 2 (Gluma Desensitizer), Group 3 (Teethmate Desensitizer), Group 4 (Nd:YAG laser), Group 5 (Er:YAG), Group 6 (Gluma + Er:YAG laser), Group 7 (Teethmate Desensitizer + Er:YAG laser) respectively, evaluate under SEM. Samples will examine using a scanning electron microcope at x2000, x1000 and x500 magnification. Total of twelve photographs from samples will take for each group. The number of open, partially occluded and total visible (open+partially occluded) dentin tubules will counte on each photograph. Atomic Force Microscopy (AFM) has been used to further substantiate the blocking mechanism. The data will analyze by one-way ANOVA and Dunnett-C tests.
Results: SEM and AFM analysis presented occlusion of dentin tubules in all treatment groups, but more prominent occlusion was observed in the combined treatment group. Groups were compared with each other the number of the occluded dentinal tubules per 100 µm2 revealed statistically significant better differences in laser groups ( p < 0.05). Group 7 demonstrated significantly more tubule occlusion when compared to all other groups. Compared to the partial or total closure of tubules, Groups 3, 4, 5 and 6 were better than group 2 ( p < 0.05).
Conclusions: The results of this study have shown that all applied treatment options were effective in the occluding of dentinal tubules, more succesfull occlusion was observed in the combined treatment group. Although all laser treatments can be effective in the treatment of dentinal hypersensitivity, desensitizing agents are much less damaging to the dentin surface compared with laser.