In Vitro Evaluation of the Efficacy of Different Over-the-Counter Products on Tooth Whitening

This in vitro study evaluated the whitening effect of four different over-the-counter products compared with a 10% carbamide peroxide (CP) bleaching gel. Specimens obtained from bovine incisors were stained in a tea solution and randomly divided into six groups according to the product used (n=10): CT: conventional toothpaste (negative control); CWT: Crest 3D White toothpaste; CWR: Crest 3D White mouth rinse; CWS: Crest 3D White strips; DW: Dazzling White (paint-on gel); and OP: Opalescence PF 10% CP (at-home bleaching gel, positive control). Over-the-counter products and 10% CP were used according to the manufacturer's recommendations. Color measurements were performed according to the CIELab system using spectrophotometer after staining, and after 4 and 8 weeks of the treatment procedure. The ∆E, ∆L, ∆a, and ∆b values were calculated. The data obtained were analyzed by repeated-measures ANOVA. Tukey's test for multiple comparisons was applied (p<0.05). All groups, except CWT, were effective in tooth whitening in comparison with conventional toothpaste. There was no significant difference in tooth whitening between CWT and CT (p=0.93). CWS, DW and OP groups presented significantly higher color changes than the CWR group. DW and CWS showed similar tooth whitening to OP.

Este estudo avaliou o efeito branqueador de quarto produtos disponíveis comercialmente em comparação com um gel branqueador contendo 10% de peróxido de carbamida (PC). Amostras obtidas de incisivos bovinos foram tingidas numa solução de chá e distribuídas aleatoriamente em seis grupos, de acordo com o produto utilizado (n=10): CT: dentifrício convencional (controle negativo); CWT: dentifrício Crest 3D White; CWR: solução para enxague Crest 3D White; CWS: tiras branqueadoras Crest 3D; DW: gel branqueador Dazzling White e OP: Opalescence PF com 10% de PC (gel branqueador para uso doméstico, controle positivo). Os produtos comerciais e PC a 10% foram usados de acordo com as instruções dos fabricantes. Foram feitas medidas de cor com o sistema CIELab com espectrofotômetro, imediatamente após o tingimento, e após 4 e 8 semanas do tratamento. Foram calculados os valores de ∆E, ∆L, ∆a e ∆b. Os dados obtidos foram analisados por ANOVA para medidas repetidas. Foi aplicado o teste de Tukey para comparações múltiplas (p<0,05). Com exceção do Grupo CWS, todos os grupos foram efetivos para o branqueamento dental na comparação com o dentifrício convencional. Não houve diferença significativa no branqueamento dental entre CWT e CT (p=0,93). Os grupos CWS, DW e OP apresentaram mudanças de cor significativamente maiores que o grupo CWR. Os grupos DW e CWS produziram branqueamento similar a OP.

Salivary clearance of sugar before and after insertion of fixed partial dentures.

Background: The development of carious lesions is dependent on the presence of acid-producing microflora in the mouth. The activity of these plaque bacteria is dependent on sugar, which diffuses from the saliva following carbohydrate intake. The sugar serves as a substrate for fermentation, producing organic acids that demineralize tooth enamel. Elimination of the sugar from the mouth is accomplished by dilution with newly secreted saliva, a process generally referred to as sugar clearence. Objectives: Determine if fixed partial prosthodontic treatment affects the length of salivary sugar clearance. Materials and methods: Fifteen male subjects age between 21 and 32, and requiring 10 porcelain fixed partial dentures were included in this study. Before receiving their dentures, the subjects, rinsed with a 10% sucrose solution for 30 seconds then gave saliva samples. The prpcedure was repeated one month after the dentures were put in place. The length of sugar clearance was calculated. Results: Salivary sugar was cleared in 14.89±0.89 minutes before the denture application and in 18.86± 0.90 minutes after denture treatment. The initial sucrose concentration was 113.63±1.29 mmol/L before the dentures and 142.99±10.82 mmol/L after the dentures. Conclusion: The use of fixed partial dentures does not affect the time required to clear salivary sugar or the level of the initial sucrose concentration.