Sodium fluoride and chlorhexidine effect in the inhibition of mutans streptococci in children with dental caries: a randomized,double‐blind clinical trial

Objective: We aimed to compare the effect of sodium fluoride and chlorhexidine on salivary levels of mutans streptococci (MS), in a double‐blind, randomized clinical trial. Methods: Thirty‐five healthy volunteers, aged 4–8 years, with at least one active carious lesion and no previous history of allergies were selected to participate in the study. A gel formulation containing either 1.23% sodium fluoride or 1% chlorhexidine was topically administered to the dentition every 24 h for 6 consecutive days. Salivary MS levels were measured at baseline (D1) and on the 6th (D6), 15th (D15), and 30th (D30) days. For microbiological analysis, Mitis Salivarius‐Bacitracin agar medium was used. Results: Difference between treatments was only verified on D6. On the last day of treatment 1% chlorhexidine gel was significantly more effective than fluoride (P = 0.0000). The use of sodium fluoride did not cause a statistically significant variation in salivary MS levels throughout the duration of the study. Following treatment, a subsequent increase in MS counts between D6 and D15 (P = 0.0001) was observed with chlorhexidine. Conclusion: A 6‐day treatment with a 1% chlorhexidine gel was effective in reducing salivary MS; there was a significant MS increase once treatment was suspended. The use of 1.23% sodium fluoride under the same regimen was not able to reduce salivary MS levels. Our results suggest repeated treatment with 1% chlorhexidine as a means for maintaining low salivary MS levels in children with dental caries.     

Effect of xylitol gum on the level of oral mutans streptococci of preschoolers: block-randomised trial

Objectives: To assess the influence of xylitol chewing gum consumption on mutans streptococci level of 3–4 years old Japanese preschoolers. Methods: 248 participants were examined regarding caries‐related factors at baseline and were followed up at 6, 9, and 12 months after the baseline: assessors were blinded, subjects were open labelled and blocked parallel randomised; 142 were selected to use xylitol gum for 3 months (from months 6 to 9) and 106 were controls. Results: 161 participants were analysed (xylitol n = 76, control n = 85). Nineteen caries‐related variables, including xylitol gum consumption, were analysed for any association with the main outcome, plaque mutans streptococci scores development within the intervention period, by logistic regression. Six showed statistically significant associations by univariate analysis (P < 0.05). However, only xylitol gum consumption remained a significant negative association (P < 0.05) by multiple analyses. Interestingly, over 10% xylitol group children experienced diarrhoea, which was larger than previous investigations. Conclusion: Xylitol gum is effective in avoiding increased plaque mutans streptococci in young children.     

Effects of xylitol, xylitolsorbitol, and placebo chewing gums on the plaque of habitual xylitol consumers

Xylitol reduces plaque but the reduction mechanism is largely unknown. The main aim of the present study was to determine whether the xylitol-induced reduction in the amount of plaque and the number of mutans streptococci could be demonstrated in subjects with (presumably) high levels of xylitol-resistant (X^R; not inhibited by xylitol) mutans streptococci acquired following previous xylitol consumptions. 37 healthy dental students participated in the double-blind study. All subjects had been uncontrolled, habitual consumers of xylitol-containing products for at least 1 yr before the study, A 1-month washout period was followed by a 2-week test period during which either xylitol, xylitol-sorbitol or unsweetened chewing gum base was chewed 3–5 × a day. Plaque and saliva samples were collected at baseline and at the 2-week point for determination of the amount of plaque, microbiological variables, and hydrolytic enzymes. Mixtures of xylitol and sorbitol seemed to perform equally well with respect to reduction in the amount of plaque but not the number of mutans streptococci. Thus, polyols were the active ingredients of chewing gums able to modulate the amount of plaque and its microbial composition. Xylitol reduced plaque with a mechanism which appeared not to be associated with the study-induced changes in the proportion (%) of mutans streptococci in plaque, the number of salivary mutans streptococci, the proportion of X^R strains in plaque or saliva, or the hydrolytic enzyme activities of plaque.     

Thirty-nine-month xylitol chewing-gum programme in initially 8-year-old school children: a feasibility study focusing on mutans streptococci and lactobacilli

AIM: To investigate the use of xylitol-containing chewing-gums in public elementary schools as a means to affect the growth of salivary and plaque mutans streptococci and salivary lactobacilli. DESIGN: Over a period of 24 months, 750 8- to 9-year-old children chewed xylitol (X group; n = 255) or xylitol-sorbitol (XS group; n = 264) gum on school days (454 days over 2 years), or chewed no gum at all (C group; n = 231). Consumption of xylitol in the X and the XS groups was 6.6 and 5.4g per day, respectively. Use of gum took place at school in four daily episodes of which three were supervised by teachers. Following the 24-month chewing-gum period, the subjects were re-examined after 15 months (total follow-up period: 39 months) at which time an extraneous comparison group (ExC; n = 117) was also examined. The numbers of subjects examined after 39 months were: X, 239; XS, 248; C3 217. METHODS: Salivary and plaque levels of mutans streptococci and the salivary levels of aerobically cultured aciduric bacteria (mostly representing lactobacilli) were determined using the Orion Diagnostica Dentocult SM and LB test kits, respectively. RESULTS: There were statistically significant differences after 24 and 39 months between the two xylitol chewing-gum groups and the C group with regard to salivary and plaque mutans streptococci and salivary lactobacilli: the use of xylitol-containing chewing-gums significantly reduced these bacterial scores. The reductions were statistically more significant in the X group than in the XS group. The bacterial scores of groups C and ExC were similar. CONCLUSIONS: Long-term use of xylitol-containing chewing-gum can reduce the growth of mutans streptococci in saliva and dental plaque, and lactobacilli-type bacteria in saliva, even if xylitol is used only on school days. The results also suggest that xylitol gum use can have a long-term, delayed growth-retarding effect on these micro-organisms, since reduced bacterial growth was still observed 15 months following the termination of xylitol use. The results indicate a close biochemical relationship between xylitol and mutans streptococci, and suggest that a similar relationship may exist regarding aerobically cultured aciduric bacteria present in saliva.     

Salivary mutans streptococci and dental caries in three-year-old children after maternal exposure to chewing gums containing combinations of xylitol,sorbitol, chlorhexidine,and fluoride

The aim of this study was to evaluate the effect of maternal use of chewing gums containing combinations of xylitol, sorbitol, chlorhexidine, and fluoride on salivary mutans streptococci (MS) counts and caries prevalence in the mothers' 3-year-old children. After screening 416 women with newborn babies, 173 mothers with high counts of salivary MS were randomly assigned into 3 experimental chewing gum groups containing (A) xylitol (n=61), (B) chlorhexidine/xylitol/sorbitol (n=55), and (C) sodium fluoride/xylitol/sorbitol (n=57). Mothers with low or medium MS counts formed a reference group (D) without any intervention (n=232). The participants in the experimental groups were instructed to chew one piece of the gum for 5 min 3 times a day. The chewing regimen started when the child was 6 months old and was terminated 1 year later. The outcome measures were salivary MS counts and caries prevalence at the age of 3 years. Bacterial enumeration was carried out with a chair-side technique and caries (defs) was scored by clinical examination. Medium and high counts of salivary MS were found in 13%, 16%, and 22% in groups A, B, and C, respectively. The mean defs was 0.1 in group A, 0.2 in group B, and 0.4 in group C. The differences concerning salivary MS and caries were not statistically significant. The MS counts and caries prevalence in children of mothers with low MS counts (group D) were similar to those found in groups A and B. In conclusion, lower but non-significant levels of salivary MS and dental decay were observed in 3-year-old children to mothers who used high-content xylitol gums compared with those who used lower amounts of xylitol. The efficiency of this type of targeted intervention in a low-caries community may be questioned.     

他克莫司含漱液治疗糜烂型口腔扁平苔藓的随机单盲对照研究

目的：评价他克莫司含漱液治疗糜烂型口腔扁平苔藓(OLP)的临床疗效。方法：采用随机单盲对照开放设计,将62例糜烂型OLP患者分为治疗组和对照组,治疗组采用他克莫司含漱液,对照组采用地塞米松含漱液,同时记录2组VAS和REU分值,使用SPSS17.0软件包对数据进行统计学分析,在用药4周和12周时分别评定疗效。结果：用药后4周和12周,2组VAS和REU分值均低于基线水平(P<0.01),2组疗效差异无显著性(χ²=0.295、0.413,P>0.01)。用药后4周,治疗组REU分值低于对照组,差异显著(P<0.01)。结论：他克莫司含漱液治疗糜烂型OLP安全可靠且起效快,可在临床推广使用。     

Xylitol disturbs protein synthesis,including the expression of HSP‐70 and HSP‐60, in Streptococcus mutans

Xylitol, a natural sugar alcohol and a caries‐preventive carbohydrate sweetener, inhibits xylitol‐sensitive wild‐type Streptococcus mutans but also selects for its natural xylitol‐resistant mutants. The aim of the work was to verify the influence of xylitol on heat shock proteins HSP‐60 (GroEL‐like) and HSP‐70 (DnaK‐like) in xylitol‐sensitive and xylitol‐resistant strains. Cells from fresh isolate S. mutans 123.1 were grown at 37°C and constant pH 7.0. The cell culture was stressed by raising the temperature to 43°C or adding xylitol (4% final). Cell proteins labeled with a cocktail of ¹⁴C‐amino acids were analyzed by SDS‐PAGE and autoradiography whereas HSP‐60 and HSP‐70 were visualized using Western immunoblotting. In both xylitol‐sensitive and xylitol‐resistant strains, heat stress was associated with an increase of both HSP‐60 (63 kDa) and HSP‐70 (71 kDa) and a decrease in the intensity of a number of other protein bands compared with cells maintained at 37°C. Exposure to xylitol but not to other polyols induced a decrease of both these heat shock proteins in the xylitol‐sensitive strain but did not modify them in the xylitol‐resistant mutant. It also decreased all protein bands above 60 kDa together with a 53 kDa protein and increased the amount of 57‐, 50‐ and 40‐kDa proteins in the xylitol‐sensitive strain whereas the proteins of the xylitol‐resistant strain remained unchanged. The results suggest that xylitol is a strong metabolic inhibitor that disturbs protein synthesis and reduces the expression of HSP‐70 and HSP‐60 proteins in the wild‐type xylitol‐sensitive S. mutans but not in the xylitol‐resistant natural mutant strain.     

Reducing mutans streptococci and caries development by Lactobacillus paracasei SD1 in preschool children: a randomized placebo-controlled trial

Objective: To examine a reducing effect of Lactobacillus paracasei SD1 on MS and caries in preschool children.

Materials and methods: A total of 124 children, aged 1.5–5 years old, participated and were randomly assigned to the probiotic or control group. The probiotic group received L. paracasei SD1-milk and the control group received standard-milk once daily for 3 months. MS/lactobacilli were enumerated and the caries score was examined. Association between probiotic consumption and bacterial level, or caries progression was assessed by a multivariate logistic regression. This study was registered at the Thai-Clinical-Trials-Registry (TCTR20140903001).

Results: Probiotic was found to be a factor associated with the MS level. Children in the probiotic group had a significantly lower risk of an increase in the MS level than in the control group after receiving the probiotic milk at 3- and 4-months with p?p?=?.040, respectively. Probiotic significantly reduced the risk for caries compared to the control group (p?=?.016). There were no adverse effects or non-compliance reported in either group.

Conclusions: Consumption of milk powder containing L. paracasei SD1 resulted in a reduction of both salivary MS and delayed new caries development, and the strain is safe for use in young children. Results suggest that L. paracasei SD1 may be an alternative way for caries prevention in young children.     

Comparison of the effects of cetylpyridinium chloride with an essential oil mouth rinse on dental plaque and gingivitis - a six-month randomized controlled clinical trial

Objective: To compare the effects of an experimental mouth rinse containing 0.07% cetylpyridinium chloride (CPC) (Crest Pro‐Health^®) with those provided by a commercially available mouth rinse containing essential oils (EOs) (Listerine^®) on dental plaque accumulation and prevention of gingivitis in an unsupervised 6‐month randomized clinical trial. Material and Methods: This double‐blind, 6‐month, parallel group, positively controlled study involved 151 subjects balanced and randomly assigned to either positive control (EO) or experimental (CPC) mouth rinse treatment groups. At baseline, subjects received a dental prophylaxis procedure and began unsupervised rinsing twice a day with 20 ml of their assigned mouthwash for 30 s after brushing their teeth for 1 min. Subjects were assessed for gingivitis and gingival bleeding by the Gingival index (GI) of Löe & Silness (1963) and plaque by the Silness & Löe (1964) Plaque index at baseline and after 3 and 6 months of rinsing. At 3 and 6 months, oral soft tissue health was assessed. Microbiological samples were also taken for community profiling by the DNA checkerboard method. Results: Results show that after 3 and 6 months of rinsing, there were no significant differences (p=0.05) between the experimental (CPC) and the positive control mouth rinse treatment groups for overall gingivitis status, gingival bleeding, and plaque accumulation. At 6 months, the covariant (baseline) adjusted mean GI and bleeding sites percentages for the CPC and the EO rinses were 0.52 and 0.53 and 8.7 and 9.3, respectively. Both mouth rinses were well tolerated by the subjects. Microbiological community profiles were similar for the two treatment groups. Statistically, a significant greater reduction in bleeding sites was observed for the CPC rinse versus the EO rinse. Conclusion: The essential findings of this study indicated that there was no statistically significant difference in the anti‐plaque and anti‐gingivitis benefits between the experimental CPC mouth rinse and the positive control EO mouth rinse over a 6‐month period.     

A preliminary randomised double‐blind placebo‐controlled clinical trial of hydroxyzine for treating sleep bruxism in children

This is a randomised placebo‐controlled clinical trial investigating the efficacy of hydroxyzine for treating parent‐reported sleep bruxism in children. Participants of this trial were 30 patients randomly allocated to one of the two groups in a ratio of 1:2. One group received hydroxyzine and the other group received placebo. The outcome measures were Visual Analogue Scale test and Clinical Global Severity scale. Assessments occurred at baseline and at the end of week 4. The side effects of drugs were assessed using a checklist. The number of children in the hydroxyzine and placebo groups was 21 and 9, respectively. The mean age of children in the hydroxyzine and placebo groups was 8·4(s.d. = 3·3) and 6·5(s.d. = 1·5) years, respectively. Hydroxyzine more than placebo decreased bruxism score (3·8 versus 2·2). No serious adverse effect was reported. Current evidence support that hydroxyzine is effective and well tolerated for treating bruxism in children.