Efficacy of different "in-office" desensitizing treatment methods: An in vitro SEM analysis

To evaluate, in vitro, the obliteration of dentin tubules promoted by different desensitizing methods, before and after pH cycling.

Human dentin blocks of 4x4 mm were randomly divided into: control group (n = 20): no treatment; Group GH (n = 20): surface treatment with a solution containing glutaraldehyde (5.1%), HEMA (36.1%), sodium fluoride (NaF), and deionized water; Group NP (n = 20): surface treatment with a calcium phosphate gel containing nanostructured hydroxyapatite crystals, NaF and NK; and Group ARG (n = 20): surface treatment with a paste containing CaCO3 and 8% arginine. After treatment, 10 samples of each group were evaluated in scanning electron microscopy (SEM) while another 10 were included in a pH cycling procedure for 48 hours, and then analyzed in the SEM. All SEM images were evaluated by three calibrated examiners regarding dentin tubular obliteration. Mann-Whitney and Kruskal-Wallis tests were used for data analysis (P < 0.05).

The GH, NP, and ARG groups promoted immediate obliteration higher than the control group (P < 0.05) with NP and ARG groups superior to GH group (P < 0.05). After pH cycling, an increase in tubular obliteration in the GH group was observed, which was similar to the NP and ARG groups (P > 0.05), even though all groups promoted higher obliteration than the control group (P < 0.05). All treatments were effective in a tubular obliteration.