Whitening efficacy and removal of extrinsic tooth stain of sodium phytate-containing whitening toothpaste: a randomized controlled trial.

Objective: The study aimed to evaluate the whitening efficacy and removal of extrinsic tooth stain of sodium phytate-containing whitening toothpaste, as well as to evaluate participant satisfaction.

Methods: A total of eighty participants were recruited for this randomized, triple-blind controlled trial and were randomly assigned to either the test group (toothpaste containing 0.875% sodium phytate, ST) or the control group (toothpaste without sodium phytate, CT). Tooth color was assessed using a VITA spectrophotometer and changes in exogenous tooth stains were evaluated using the Lobene Index, which were conducted at baseline, as well as at 2, 3, and 4 weeks. Additionally, participants' self-assessment of tooth color were evaluated through an aesthetic numerical analogue scale. Statistical tests were conducted appropriately, and the significance level was established at α = 0.05.

Results: This study demonstrates that the b-value of the index teeth in the ST group was significantly lower (p < 0.05) than that of the CT group, while the △WI values were significantly higher (p < 0.05) at both the 3-week and 4-week time points. Additionally, the a-value of the index teeth in the ST group was significantly lower (p < 0.05) compared to the CT group, and the L-value of the index teeth in the ST group was significantly higher (p < 0.05) than that of the CT group after 4 weeks. The differences in color between the two treatments, as analyzed by the CIELAB (ΔE), were not statistically significant. Similarly, no significant differences were observed in the changes of the Lobene Index or in participant satisfaction regarding tooth color between the two groups. A comparative analysis of the subjects in the ST group at the 3-week and 4-week marks revealed that the L-value of the index tooth at 4 weeks was significantly higher than that at 3 weeks (p < 0.001), while the b-value was significantly lower at 4 weeks compared to 3 weeks (p < 0.001).

Conclusion: Brushing teeth with sodium phytate-containing whitening toothpaste for a duration of three weeks demonstrates notable whitening effects, which significantly increase over time. However, after four weeks, the sodium phytate-containing toothpaste shows minimal efficacy in removing extrinsic tooth stains.

Clinical Significance: Sodium phytate may be incorporated into toothpaste as a whitening agent.