Risco absoluto de sensibilidade com e sem Ativação sônica de um gel dessensibilizante previamente ao clareamento de consultório

Abstract

This clinical trial evaluated the effect of sonic activation of a desensitizing gel on ocurrance of in office bleaching associated sensitivity. 31 patients had their maxilar anterior teeth divided into left and right, according with sonic activation (AS) or not (SS) of desensitizing gel. Before bleaching, a desensitizing gel containing 5% potassium nitrate and 2% sodium fluoride (Desensibilize KF2%, FGM, Joinville/SC, Brazil) was applied. Sonic activation was made with a sonic device (Smart, FGM, Joinville/SC, Brazil), applied 15 seconds on tooth in AS side then, 15 seconds in other sites (lips, marginal gingive, pre-molar) to blind the participant, until each tooth in the AS side had received 30 seconds of activation. After sonic activation, desensitizing gel were removed only from the AS side, in the SS side it remained in rest until complete 10 minutes as recommended by fabricant. Once the desensitizing gel were removed from both sides, gingival tissues were isolated with a lightcured resin barrier (Top Dam, FGM, Joinville/SC, Brazil). 35% hidrogen peroxide gel (Whiteness HP Maxx, FGM, Joinville/SC, Brazil) was used in two bleaching sessions of 45 minutes. Enamel craze lines presence was also evaluetad by transilumination. Changes in color were evaluated with aid of two shade guides and spectrophotometer. Tooth sensitivity was registered by a sensitivity diary, answered by the patient in a 48h period after each bleaching session. Absolute risk of sensitivity was compared by McNemar test (a=5%). Color alteration was assessed by changes in shade guide units (DSGU) and by ΔE value, wich were compared by t Student test (a=5%). No significant difference between treatments was observed about tooth sensitivity prevalence, with 93% occurrence (p=1,00) for patients of both treatments (AS and SS). Also, no difference to the color alteration for both treatments, showing a Vita Classical DSGU mean of 6,35 for both (p=0,87). Enamel craze lines’s presence was observed of more than 70% of bleached teeth for both sides. After two bleaching sessions, the use of desensitizing gel with or without sonic activation did not reduced the prevalence nor sensitivity intensity. The use of desensitizing gel with or without sonic activation did not reduce in office dental bleaching eficacy.