ABSTRACT
OBJECTIVES: To evaluate the effectiveness of sodium bicarbonate dentifrices in reducing gingivitis and tooth abrasiveness and improving tooth gloss, as compared to a conventional fluoride/silica-containing dentifrice. METHODS: In this double-blinded, randomized clinical study with a paralleled design, 73 healthy adult volunteers (age, 18-39 years), with more than 20 teeth were selected and randomly allocated to the following groups: a control group, a 35% baking soda group, and a 65% baking soda group. Professional plaque controls were provided to all subjects and the same control dentifrice was used for 14 days. At baseline, all subjects received an assigned dentifrice and were instructed to brush three times daily. The tooth gloss and gingival bleeding index were measured at baseline, 45, and 90 days. For measuring surface roughness, toothbrushes were replaced with electronic tooth-brushing machines, and the bovine specimen was brushed via 10,000 horizontal shuttle movements. The surface roughness was measured by a confocal laser scanning microscope (CLSM; Carl Zeiss, LSM-5 Pascal, Germany) Each variable was analyzed by the paired t-test, and change in each variable among groups was analyzed by analysis of variance (ANOVA). Reliability of the gloss was analyzed by an intra-class correlation coefficient. RESULTS: Compared to the controls, the 65% sodium bicarbonate dentifrice group showed significant improvement with regard to the tooth gloss for 90 days as well as a significant inhibitory effect on gingivitis; the 35% sodium bicarbonate dentifrice group, however, showed no inhibitory effect on gingivitis. The relative roughness of the tooth surface in the dentifrices of both the sodium bicarbonate dentifrice groups was significantly low. Further, there was no significant difference with the distilled water group. CONCLUSIONS: The sodium bicarbonate dentifrice has an inhibitory effect on gingivitis. Further, this dentifrice showed low abrasiveness and a glossing effect on teeth.
Subject(s)
Adult , Humans , Dentifrices , Gingivitis , Hemorrhage , Sodium Bicarbonate , Tooth , Volunteers , WaterABSTRACT
Purpose: Bicarbonate (HCO-3) is an alkaline and buffering substance found in dentifrices, which could improve the anti-caries effect of fluoride (F). However, HCO-3 could reduce the formation of calcium fluoride-like (CaF2), the most important product of F reactivity with enamel, whose formation is higher in low pH. The aim of this in vitro study was to evaluate if HCO-3 interferes with the reactivity of F with human enamel. Methods: Five dentifrice formulations were evaluated: placebo of F and HCO-3 (pH 7.0); HCO-3 (pH 9.0); F (pH 7.0); F (pH 9.0) and F+HCO-3 (pH 9.0). F dentifrices contained NaF and all dentifrices were silica-based. The concentrations of total F (TF), CaF2 and firmly bound F (FA, fluorapatite-like) formed in enamel after 1-min reaction with dentifrice slurries (1:3) were determined. Results: The formation of TF, CaF2 and FA was reduced in 22.1 %, 47.9 % and 4.8 %, respectively, by the presence of HCO-3 in the dentifrice formulation. Conclusion: This in vitro data suggest that addition of HCO-3 to a dentifrice may interfere with the reactivity of F with enamel, reducing mainly the concentration of CaF2 formed.
Objetivo: O bicarbonato (HCO-3 ) é uma substância alcalina e tamponante encontrada em dentifrícios, que poderia melhorar o efeito anticárie do fluoreto (F). No entanto, HCO-3 poderia reduzir a formação de fluoreto de cálcio (CaF2), o mais importante produto da reatividade do F com esmalte, cuja formação é maior em baixo pH. O objetivo deste estudo foi avaliar in vitro se o HCO-3 interfere na reatividade do F com o esmalte humano. Metodologia: Cinco formulações de dentifrícios foram avaliadas: placebo de F e HCO-3(pH 7,0); HCO-3 (pH 9,0); F (pH 7,0); F (pH 9,0) e F+HCO-3 (pH 9,0). Os dentifrícios fluoretados continham NaF e todos continham sílica como abrasivo. As concentrações de F total (FT), CaF2 e F firmemente ligado (FA, tipo flúorapatita) formadas no esmalte após 1 minuto de reação com as suspensões dos dentifrícios (1:3) foram determinadas. Resultados: A formação de FT, CaF2 e FA foram reduzidas em 22,1 %; 47,9 % e 4,8 %, respectivamente, pela presença de HCO-3 na formulação do dentifrício. Conclusão: Os resultados in vitro sugerem que a adição de HCO-3 a um dentifrício pode interferir com a reatividade do F com o esmalte, principalmente reduzindo a concentração de CaF2 formado no esmalte.