Investigation of oral malodor prevention by dentifrices as measured by VSC reduction

Abstract

The oral malodor reduction efficacy of dentifrices containing stannous fluoride (SnF₂) or zinc plus arginine (Zn/Arg) was evaluated using a halimeter to measure volatile sulfur compounds (VSCs) in two randomized, controlled, single-blind, cross-over pilot clinical trials. Study 1 (N= 16) had five 1100 ppm F dentifrices and five treatment periods: negative control (NC): 0.243% sodium fluoride (NaF); SnF₂A: 0.454% SnF₂+ pyrophosphate; SnF₂B: 0.454% SnF₂+ sodium hexametaphosphate; SnF₂C: 0.454% SnF₂+ citrate; and SnF₂D: experimental 0.454% SnF₂with increased bioavailable Sn. Study 2 (N= 16) had four 1450 ppm F dentifrices and four treatment periods: NC: 0.1% NaF + 0.76% sodium monofluorophosphate; Zn/Arg: NaF + zinc + arginine; SnF₂E: 0.454% SnF₂+ 0.078% NaF + sodium hexametaphosphate; SnF₂F: 0.454% SnF₂+ 0.078% NaF + citrate. Each period took 96 h; baseline (day 0) morning to day 4 morning. Subjects brushed 2x/day with the treatment dentifrice. VSC levels were measured in the morning, prior to morning brushing, on days 0 and 4. Changes in VSC scores from day 0 to day 4 were assessed using a mixed-model analysis of covariance for cross-over studies. In study 1, SnF₂dentifrices B, C and D showed statistically significant reductions (31.3%, 24.8%, 34%, respectively) in VSC scores versus baseline (p< 0.001); the benefits of these treatments versus NC and SnF₂dentifrice A were statistically significant (p⩽ 0.001). In study 2, SnF₂dentifrices E and F showed statistically significant reductions (31.2%, 22.1%, respectively) in VSC scores versus baseline (p⩽ 0.010); the benefits of these treatments versus NC and the Zn/Arg dentifrice were statistically significant (p⩽ 0.035). The Zn/Arg dentifrice showed a significant increase of 35.2% (p< 0.001) in VSC scores versus baseline. These studies demonstrated that SnF₂dentifrices can provide significant oral malodor reductions, but the benefit is formulation dependent. The presence of SnF₂is not sufficient to ensure efficacy. The Zn/Arg dentifrice increased VSC levels, indicating greater malodor.Clinical Trial Numbers: 20190429 and 20191028.

Keywords: SnF2 dentifrice; VSCs; halimeter; oral malodor; single-blind cross-over clinical trial; zinc/arginine dentifrice.