Clinical evaluation of Light activated In-office bleaching when pretreatment with desensitizing agent containing Tricalciumphosphate

Objectives: The aim of this clinical randomized controlled split-mouth study was to evaluate the effect of pretreatment with desensitizing agent containing Tricalciumphosphate (TCP) to shade changes and tooth sensitivity (TS) during bleaching procedure.
Methods: This split-mouth design was performed on canine tooth of 15 patients, with pretreatment of TCP agent (Clinpro™ White Varnish with TCP) before bleaching in one hemi-arch but not in the other. The application of distill water and CCP-ACP (toothmousse, GC Corp, Japan) was used as negative and positive control applied on canine tooth of the other hemi-arch, respectively. Then all teeth were bleached with 30% Hydrogenperoxide (Me too!, Acteon (Thailand) Co., Ltd, Thailand) for 3 applications of 15 min per each session under full mode of blue light activation. Tooth sensitivity (TS) was determined by VAS score during the bleaching procedure. Tooth color was immediately evaluated after completing the treatment by digital spectrophotometer (Vita Easyshade, Vita, USA) as color parameters; L*, a* and b*, and subjectively using VITA Classic shade guide. △E and TS were analyzed by using using Wilcoxon Mann-Whitney U test and Chi-square test respectively.
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Results: The significant shade changes (△E = 3.03-4.89, P < 0.05) was noticed in both hemi-arches. However, the △E of TCP and CCP-ACP pretreatment group was lower than the one without but not significantly different (P>0.05). The tooth sensitivity significantly reduced on canine tooth with application of TCP (P < 0.05).
Conclusions: The pretreatment with TCP before starting bleaching may help to reduce tooth hypersensitivity during bleaching procedure and did not affect the shade changes.