The influence of mouthrinses with antimicrobial solutions on the inhibition of dental plaque and on the levels of mutans streptococci in children

The effect of daily mouthrinses on dental plaque accumulation and on salivary mutans streptococci was investigated in 200 children. The utilized solutions were: a placebo solution composed of mentholated deionized water (group I); 0.12% chlorhexidine gluconate associated to 0.05% sodium fluoride (group II); 0.2% chlorhexidine digluconate (group III), and 0.5% stevioside mixed with 0.05% sodium fluoride, with pH 3.4 (group IV). In order to verify the effect on plaque formation, the accumulation of plaque was assessed by means of the Löe12 index, at the beginning and at the end of the experiment, whereas the quantification of cariogenic streptococci was accomplished on three saliva samples collected at 3 different moments: before the first mouthrinse, 24 hours after the first mouthrinse and 1 week after the last mouthrinse. The mouthrinsing routine was carried out on a daily basis during 4 weeks. Five milliliters of solution were rinsed during 1 minute. The results revealed 4.10, 26.75, 41.20, and 5.91% of reduction in plaque accumulation for groups I, II, III, and IV, respectively. Comparisons between the groups as to plaque reduction revealed that groups II and III were significantly different from groups I (control) and IV (p < 0.05), but did not differ from each other. The solution utilized by group III was the least accepted by children and, as the solution utilized by group II, caused mild dental pigmentation. There were no statistically significant differences as to the levels of mutans streptococci, probably due to the low initial levels observed in each one of the four groups.Avaliou-se, num total de 200 crianças, o efeito de bochechos diários com solução placebo de água deionizada mentolada (grupo I); gluconato de clorexidina 0,12% associado ao fluoreto de sódio 0,05% (grupo II); digluconato de clorexidina 0,2% (grupo III) e esteviosídeo 0,5% associado ao fluoreto de sódio 0,05% pH 3,4 (grupo IV), sobre o acúmulo de placa dentária e o nível de estreptococos mutans salivares. Utilizando-se o índice de Löe12, o acúmulo de placa dentária foi avaliado no início e no final do experimento, enquanto os níveis de estreptococosmutans foram quantificados com o Caritest SM em 3 momentos: antes do primeiro bochecho, 24 horas após o primeiro bochecho e 1 semana após o último bochecho. O regime de bochechos foi diário, com 5 ml de solução, por 1 minuto, durante 4 semanas. Os resultados mostraram uma inibição do acúmulo de placa de 4,10%, 26,75%, 41,20% e 5,91% para os grupos I, II, III e IV, respectivamente. A comparação entre os grupos quanto a redução da placa revelou que os grupos II e III diferiram significantemente dos grupos controle (I) e IV (p < 0,05), mas não entre si. A solução do grupo III foi a de menor aceitação pelas crianças e, juntamente com a solução do grupo II, promoveu pigmentações dentárias suaves. Não se registrou diferença significante nos níveis de estreptococos mutans em nenhum grupo, provavelmente devido aos baixos valores iniciais observados em todos os grupos

In vitro quantitative evaluation of marginal microleakage in class II restorations confected with a glass ionomer cement and two composite resins

This study evaluated, in vitro, marginal microleakage in class II restorations confected with the glass ionomer cement Vitremer and with the composite resins Ariston pHc and P-60. The aims of the study were to assess the effect of thermocycling on those materials and to evaluate two methods utilized in the analysis of dye penetration. Sixty premolars divided in three groups were utilized; the teeth had proximal cavities whose cervical walls were located 1 mm below the cementoenamel junction. Half of the test specimens from each group underwent thermocycling; the other half remained in deionized water, at 37ºC. The specimens were immersed, for 24 hours, in a basic 0.5% fuchsin solution at 37ºC. For the analysis of microleakage, the specimens were sectioned in a mesio-distal direction, and the observation was carried out with the software Imagetools. The results were evaluated through the 2-way ANOVA and through the Tukey?s test. All groups presented marginal microleakage. The smallest values were obtained with Vitremer, followed by those obtained with the composite resins P-60 and Ariston pHc. There was no statistically significant difference caused by thermocycling, and the method of maximum infiltration was the best for detecting the extension of microleakage

Fluoride kinetics in saliva after the use of a fluoride-containing chewing gum

There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using the HappydentTM chewing gum, which contains 3.38 mg of fluoride as monofluorophosphate. Fifteen 7-9-year-old volunteers were instructed to chew the gum TridentTM (control) and HappydentTM on different days. Total saliva was collected for 3 minutes, at 0, 3, 6, 9, 15, 30 and 45 minutes after starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (Orion 96-09) after acid hydrolysis. The data were analyzed by two-way analysis of variance and by Tukey’s post hoc test (p < 0.05). The mean amounts ± sd (mg) of fluoride released in saliva were 0.276 ± 0.126 and 0.024 ± 0.014 for HappydentTM and TridentTM respectively. The fluoride amount in the saliva samples after the use of Happydent was significantly higher than after the use of TridentTM in all experimental periods, except after 30 and 45 minutes. The high fluoride presence in saliva after the use of Happydent may be significant to prevent dental caries and this should be evaluated in clinical researches. On the other hand, children at an age of risk for dental fluorosis should avoid the use of HappydentTM