Background. The authors undertook a study to measure how the addition of amorphous calcium phosphate (ACP) to a professionally dispensed 16 percent carbamide peroxide equivalent bleaching gel affects tooth color and dentinal hypersensitivity.
Methods. The authors assigned two groups to use either the test gel containing ACP or a control gel. Both groups used their respective products for three hours daily for 14 days. At checkpoints during the treatment period, the authors studied tooth color, gingival health and three measures of hypersensitivity. They performed double-blinded clinical measurements on days three, seven, 14 and on the fifth day post-treatment.
Results. The test group demonstrated significantly lower (P < .05) mean thermal sensitivity scores compared with baseline (day 14: 0.21 versus 0.31; fifth posttreatment day: 0.06 versus 0.18). Tactile sensitivity also was substantially lower (P < .05) for test subjects (day 14: 0.26 versus 0.48; fifth posttreatment day: 0.06 versus 0.19). Furthermore, at the conclusion of the study, twice as many subjects were free of thermal sensitivity (test group, 80 percent, compared with control group, 40 percent; P < .001) and there was a similar significant (P < .001) percentage difference for tactile sensitivity. Both groups demonstrated equivalent and significant tooth color enhancement as compared with baseline (control: –7.73 shade change versus test: –8.12; P < .05).
Conclusions. This study demonstrates that ACP could be added to a 16 percent carbamide peroxide equivalent bleaching gel and result in a significant reduction of clinical measures of dentinal hypersensitivity, both during and after treatment.
Clinical Implications. The results of this study offer evidence in support of clinical decisions to treat patients with bleaching gel containing ACP when uncompromised tooth whitening efficacy is desired, yet dentinal hypersensitivity may be a concern.
