Salem Alshara1, Frank Lippert, George J Eckert, Anderson T Hara. 1. Oral Health Research Institute, Department of Preventive and Community Dentistry, Indiana University School of Dentistry, 415 N. Lansing Street, Indianapolis, 46202-2876, IN, USA.
Abstract
OBJECTIVES: This study was conducted in order to investigate the mode of action and the whitening effect of whitening dentifrices. MATERIAL AND METHODS: Two hundred fifty-six bovine enamel specimens (10 × 10 mm(2)) were prepared, partially stained, and assigned into eight groups (n = 32): six whitening dentifrices, one nonwhitening and deionized water (negative control), and further divided in two subgroups (n = 16), according to the test model: chemical (dentifrice slurry treatment only) or chemo-mechanical (slurry + toothbrushing). Specimens were treated with dentifrice slurries 2 ×/day for 1 min and toothbrushed or not, according to each model. In between dentifrice treatments, specimens were artificially stained for 5 h. This protocol was repeated for 5 days and enamel color changes (∆E) were measured after each day (days 1-5). The abrasive level of the dentifrices was determined following the ISO11609 guidelines. RESULTS: In the chemo-mechanical model, the whitening action of all dentifrices was observed after day 1, being higher than the negative control group (p < 0.05). In days 2-5, nonsignificant changes in color were observed for all groups (p > 0.05). Differences on ∆E among dentifrices were observed, and they seemed to correlate well with their abrasive level (r(2) = 0.80). In the chemical model, no significant differences were observed among groups (p > 0.05), with ∆E remaining constant throughout the study. Higher ∆E values were observed in the chemo-mechanical model compared to the chemical (p < 0.05). CONCLUSIONS: All tested dentifrices were effective in whitening stained enamel and their mode of action showed to be mainly mechanical (toothbrushing abrasion). CLINICAL RELEVANCE: The abrasive level of dentifrices seems to determine its whitening effectiveness.
OBJECTIVES: This study was conducted in order to investigate the mode of action and the whitening effect of whitening dentifrices. MATERIAL AND METHODS: Two hundred fifty-six bovine enamel specimens (10 × 10 mm(2)) were prepared, partially stained, and assigned into eight groups (n = 32): six whitening dentifrices, one nonwhitening and deionized water (negative control), and further divided in two subgroups (n = 16), according to the test model: chemical (dentifrice slurry treatment only) or chemo-mechanical (slurry + toothbrushing). Specimens were treated with dentifrice slurries 2 ×/day for 1 min and toothbrushed or not, according to each model. In between dentifrice treatments, specimens were artificially stained for 5 h. This protocol was repeated for 5 days and enamel color changes (∆E) were measured after each day (days 1-5). The abrasive level of the dentifrices was determined following the ISO11609 guidelines. RESULTS: In the chemo-mechanical model, the whitening action of all dentifrices was observed after day 1, being higher than the negative control group (p < 0.05). In days 2-5, nonsignificant changes in color were observed for all groups (p > 0.05). Differences on ∆E among dentifrices were observed, and they seemed to correlate well with their abrasive level (r(2) = 0.80). In the chemical model, no significant differences were observed among groups (p > 0.05), with ∆E remaining constant throughout the study. Higher ∆E values were observed in the chemo-mechanical model compared to the chemical (p < 0.05). CONCLUSIONS: All tested dentifrices were effective in whitening stained enamel and their mode of action showed to be mainly mechanical (toothbrushing abrasion). CLINICAL RELEVANCE: The abrasive level of dentifrices seems to determine its whitening effectiveness.
Authors: Ghada AlOtaibi; Majed S AlMutairi; Mofareh Z AlShammari; Mohammed AlJafar; Turki F AlMaraikhi Journal: J Family Med Prim Care Date: 2020-07-30