RESUMO
PURPOSE: To evaluate the effect of nanohydroxyapatite ( nHAP) associated with photobiomodulation (PBM) in the control of dentin hypersensitivity (DH). (C-Shape It). METHODS: 32 subjects with 83 hypersensitive teeth were randomized into four groups (N =8) : GPlacebo - simulated PBM (without light emission) followed by the application of nHAP-free toothpaste; GLaser - PBM followed by the application of nHAP-free toothpaste; GnHAP - simulated PBM followed by the application of nHAP; GLasernHAP - PBM followed by the application of nHAP. A visual analogue scale (VAS) was used to measure DH after a tactile and evaporative stimulus. DH evaluations were performed at four times: baseline, 1st, and 2nd treatment sessions, and 1 month. A questionnaire was used to evaluate the risk factors associated with DH intensity. Mixed-design ANOVA followed by Tukey test and logistic regression were used. RESULTS: The mechanical stimulus showed a significant reduction in DH in all experimental groups (P< 0.05) at the 2nd treatment session. For the evaporative stimulus, the GLasernHAP group presented a significant reduction in DH at the 1st treatment session (P< 0.05). Intragroup analysis showed that only the GnHAP group showed regression of DH at 1 month for the two applied stimuli. The variables of parafunctional habits, diets rich in acidic drinks and anxiety had significant relationships with the intensity of DH (P< 0.05). CLINICAL SIGNIFICANCE: The use of nHAP and application of PBM to laser are effective in the control of dentin hypersensitivity. However, their association did not enhance the desensitizing effect.
