Effect of xylitol chewing gum on salivary Streptococcus mutans in preschool children

Dental caries remains a significant problem for poor children in the United States. One strategy for treating dental caries is to suppress streptococcus mutans, the chief pathogen responsible for the disease. The purpose of this study was to evaluate the effect of xylitol gum in salivary S. mutans levels in preschool children. Sixty-one children were randomly assigned into the xylitol group and the control group. The xylitol group chewed gum sweetened only with xylitol (XyliFresh100%, Hershey Food Corporation, U.S.A.) three times a day for three weeks. S. mutans counts were tested using the Dentocult-SM Strip Mutans-test (Orion Diagnostica, Finland) at baseline and after three weeks. The shift from higher S. mutans scores to lower was greater in the xylitol group than in the control group (p;lt0.05). This study supports the suggestion that chewing xylitol gum may reduce salivary S. mutans levels. Xylitol chewing gum may provide a feasible caries prevention method for preschool children.     

Maintaining mutans streptococci suppression with xylitol chewing gum

BACKGROUND: One strategy for treating dental caries is to suppress oral mutans streptococci, or MS, with chlorhexidine, or CHX, mouthrinse. Oral MS levels, however, tend to quickly return to baseline values without further intervention. In this clinical study, the authors evaluated the effect of xylitol chewing gum on MS regrowth. METHODS: The authors selected 151 subjects with elevated oral MS levels (> or = 105 colony-forming units per milliliter, or CFU/mL, of paraffin-stimulated saliva). Subjects rinsed with 0.12 percent CHX gluconate mouthrinse twice daily for 14 days. The authors then randomly assigned the subjects to one of three groups. Those in the test group (n = 51) chewed a commercial xylitol gum three times daily for a minimum of five minutes each time for three months. The placebo group subjects (n = 50) used a commercial sorbitol gum, and the control group subjects (n = 50) did not chew gum. The authors estimated MS load on the dentition using paraffin-stimulated saliva samples. The authors serially diluted the samples, plated them on selective media and incubated them anaerobically; they then enumerated the colonies under a stereomicroscope. RESULTS: MS levels were not significantly different between the three groups at baseline (mean log CFU/mL +/- standard deviation: 5.4 +/- 0.7, 5.4 +/- 0.8, 5.2 +/- 0.7, respectively) nor after CHX therapy (2.7 +/- 0.8, 3.1 +/- 1.1, 3.0 +/- 1.1, respectively). After three months of gum chewing, the test group subjects had significantly lower salivary MS levels (3.6 +/- 1.2) than did the placebo (4.7 +/- 1.2) or control (4.4 +/- 1.3) group subjects. CONCLUSIONS: Xylitol chewing gum appears to have the ability to prolong the effect of CHX therapy on oral MS. CLINICAL IMPLICATIONS: Maintaining long-term caries-pathogen suppression is feasible with currently available commercial products and can be expected to result in significant caries inhibition.     

咀嚼木糖醇口香糖后牙菌斑pH值的变化趋势

目的:接触法测定咀嚼木糖醇口香糖后牙菌斑原位pH值的变化趋势。方法:在9名志愿者停止口腔卫生措施48h后,采用pH微电极测定其菌斑原位pH值作为基线,再含漱0.1kg/L蔗糖溶液后测定即刻、3、8、13、20、30、40min时的菌斑pH值,然后分别咀嚼蔗糖口香糖和木糖醇口香糖,测定以上相同时间点、相同位点的菌斑pH值。结果:受试者含漱0.1kg/L蔗糖溶液和咀嚼蔗糖口香糖后,3~13min时降到最低值,此后菌斑pH值缓慢回升,至30~40min时与基线水平无显著性差异。而咀嚼木糖醇口香糖后,菌斑pH值呈上升趋势,3min时达最高,13min后pH值逐渐接近基线水平(与基线水平无显著性差异)。木糖醇口香糖组与蔗糖口香糖组、0.1kg/L蔗糖溶液组相比,pH值下降幅度在不同时间点均有显著性差异。结论:咀嚼木糖醇口香糖可以升高牙菌斑pH值,有促进釉质再矿化的功效。     

The effect of sugar alcohols on plaque and saliva level of Streptococcus mutans

The usage of sucrose substitutes such as polyols in snack-type foods is a logical and practical means of reducing caries incidence without perturbing normal dietary eating patterns. S. mutans and L. casei can ferment mannitol and sorbitol, but are inactive towards xylitol. This ability of these cariogenic organisms to ferment the hexitols does not seem to be of concern when gums containing them are used at the normal rate. However, when hexitol gum usage is excessive, the S. mutans levels may increase. In contrast to the hexitols, excessive usage of gums sweetened with xylitol caused a significant decrease in the levels and proportions of S. mutans in saliva and plaque. While this effect on S. mutans may be an indirect one, this finding provides added evidence for the superiority of xylitol as a sucrose substitute in dentistry.     

咀嚼木糖醇口香糖对牙面菌斑原位pH值的影响

目的通过对牙面菌斑原位pH值的动态检测，观察咀嚼木糖醇口香糖对牙菌斑pH值的影响。方法采用受试者自身对照的试验方法，选择9名健康成人志愿者为受试对象，用pH微电极在口内测定菌斑的原位pH值。在测定受试者牙面48小时成熟菌斑的基线pH值之后用10％的蔗糖溶液漱口，测定漱口后即刻、3、8、13、20、30、40分钟后菌斑的pH值，然后分别咀嚼蔗糖口香糖和木糖醇口香糖，测量相同时间点、相同位点牙菌斑的pH值。结果用10％的蔗糖溶液漱口后牙菌斑pH值迅速下降至5．5以下，咀嚼蔗糖口香糖后牙菌斑pH值也有下降。但下降幅度较小，在即刻、3、8分钟三个时点二者之间有显著性差异（P〈0．05）。咀嚼木糖醇口香糖后牙菌斑的pH值没有下降，在即刻、3、8、13、20分钟五个时点的pH值明显高于咀嚼蔗糖口香糖后的pH值（P〈0．05）。结论咀嚼木糖醇香糖不会导致口腔中牙菌斑pH值的下降，有助于釉质再矿化。     

Long-term xylitol consumption and mutans streptococci in plaque and saliva

The effect of 4 to 6 years of habitual use of xylitol gum (greater than or equal to 2 times per day) on the viable counts of mutans streptococci in both plaque and saliva was evaluated in a cross-sectional study of participants of the Ylivieska xylitol study (Finland, 1982-1984). Paraffin-stimulated saliva was collected first, whereafter the remaining plaque was collected from all available tooth surfaces and pooled. The habitual xylitol consumers (n = 15) had less plaque than the controls (n = 21). The total viable counts of mutans streptococci in the plaque collected from the habitual xylitol users were about 10% of those determined in controls (p less than 0.01). The salivary mutans streptococci levels were relatively high in both habitual xylitol consumers and controls, as determined using a plate count and with an adhesion-based assay; no significant differences were detected between these groups. Thus, habitual xylitol consumption appeared not to be associated with a reduction in the total numbers of mutans streptococci in saliva. The plaque and the mutans streptococci were, however, more loosely bound to the tooth surfaces of the habitual xylitol users. The results of the plate count and the adhesion-based assay for salivary mutans streptococci were in good agreement for both habitual xylitol consumers and the controls. This suggests that it was the accumulation of plaque rather than the adhesiveness of mutans streptococci that was affected by the habitual consumption of xylitol.     

The effect of xylitol on Streptococcus mutans in children

A study was performed on 91 second-grade students from the Los Angeles Unified School District to test the effects of xylitol chewing gum on Streptococcus mutans in the saliva. Saliva was collected from students and tested for the first time using the new University of California, Los Angeles, monoclonal antibody testing method. Students found to have moderate or high levels of salivary S. mutans were administered four tablets/day of xylitol gum for three weeks. The levels of S. mutans in the saliva of children in the high caries index subgroup decreased by 61.7 percent. Xylitol can be dispensed in a public school setting by school nurses and can be a very safe, efficient and inexpensive preventative measure for children at high risk for dental caries.     

Long-term effect of xylitol chewing gum on dental caries

About 85% (n = 269) of the subjects who participated in the Ylivieska follow-up studies on the effect of xylitol chewing gum on dental caries during 1982-84 or 1982-85 were re-examined in 1987 for the analysis of possible long-term preventive effects. Further caries reduction was found 2 or 3 yr after the discontinuation of the use of xylitol. The effect was especially marked in girls; the reduction in caries increment in the post-use years was 60% for the 2-yr users, suggesting that more pronounced caries reduction was associated with the most regular use of xylitol. In teeth erupting during the first year of the use of xylitol gum the long-term preventive effect was greater than in other teeth. Several explanations are suggested: lasting effect of the microbiological changes in the mouth, bacterial colonization on newly erupted teeth by organisms other than S. mutans, and/or thorough maturation of the teeth under favorable physico-chemical circumstances. The results suggest that the value of xylitol in caries prevention depends on the timing of the treatment in relation to the development of the dentition.     

Streptococcus mutans in plaque and saliva and the development of caries

Abstract— Plaque samples from 10 different tooth surfaces of 10 schoolchildren with Varied Caries experience (DFS 10-33) were collected five times during 2.5 years. The samples were examined with an immunofluorescent technique for identification and enemeration of Sreptococcus mutans scrotypes C/e/f and d/g. At each sampling occasion the children were scored for caries. A Stimulated saliva sample was also collected and the number of S. mutans per ml salva was determined. The salva level of S. Mutans was Shown to reflect the prevalence and proportion of this microorganism on theselected surfaces. Five surfaces carried S. nutans at each sampling. Four of these surfaces showed progressive caries. S. mutans infection was also found to precede the development of incipient caries on four surfaces. Eighty percent of the surfaces that stayed sound were only transiently carrriers of S. mutans in mainly very low numbers. Serotype c/e/f dominated in prevalence and proportion on the surfaces with a history of caries during the study.     

The effect of chlorhexidine acetate/xylitol chewing gum on the plaque and gingival indices of elderly occupants in residential homes

AIM: A randomised, controlled, double-blind, clinical trial was conducted to investigate the effect of a chlorhexidine acetate/xylitol gum (ACHX) on the plaque and gingival indices of 111 elderly occupants in residential homes. A gum containing xylitol alone (X) and a no gum (N) group was included. Participants' opinions about chewing gum were also investigated. METHODS: Subjects chewed 2 pellets, for 15 min, 2x daily for 12 months. RESULTS: In the ACHX group, the plaque and gingival indices significantly decreased (p<0.001) over the 12 months. In the X group, only the plaque score significantly decreased (p<0.05) and in the N control group, both indices remained high and did not change significantly. The acceptance of both chewing gums was high but more participants in the ACHX group felt that the gum kept their mouth healthy (p<0.05). The effect of the ACHX gum on plaque and gingival indices was significantly greater than for the X gum. CONCLUSION: The long-term use of a chlorhexidine acetate/xylitol chewing gum may therefore support oral hygiene routines for an elderly dependent population.     

Genotypes of Streptococcus mutans in saliva versus dental plaque

OBJECTIVE: The aim of this study was to investigate whether genotypes of Streptococcus mutans strain can be detected as effectively in saliva samples as in plaque samples from buccal surfaces and occlusal surface fissures of permanent first molars. DESIGN: The study included 20 school children aged 6-7 years who were positive for mutans streptococci. Samples of stimulated saliva and of dental plaque on buccal surfaces and occlusal surface fissures of permanent first molars were collected. Samples were cultivated in MSB agar. Up to nine isolates compatible with mutans streptococci were obtained and identified by means of biochemical tests. All isolates identified as S. mutans were genotyped by arbitrarily primed polymerase chain reaction. RESULTS: A total of 28 genotypes of S. mutans were isolated: 23 in saliva samples, 23 in buccal surface plaque samples, and 16 in plaque samples from occlusal surface fissures. CONCLUSIONS: Although, saliva sampling did not reveal all genotypes isolated, it was equally as effective as plaque sampling from the buccal surfaces of permanent first molars, and more effective than plaque sampling from fissures on their occlusal surfaces.     

The effect of chewing urea-containing gum on plaque acidogenic and alkaligenic parameters

The aim of this double-blind crossover study was to determine the effect of chewing urea-containing gum on selected microbiological plaque properties. Eleven subjects chewed either urea-containing or urea-free placebo gum 3 times daily, each for 4 weeks, with at least a 4-week separation between regimes. After each chewing regime, plaque was sampled from all available surfaces, and inoculated into media indicative of acid or base production. In addition, interdental pH measurements were taken using touch Beetrode electrodes following sucrose and sorbitol mouthrinses, and sucrose mouthrinses followed by urea rinse, urea gum, or placebo gum. No significant differences in plaque acidogenic and alkaligenic properties were found between the urea and placebo gum regimes. Urea rinsing, urea gum and placebo gum all reduced the depth and duration of the pH fall following a sucrose mouthrinse. They also enhanced a rise in pH above the resting pH, but although urea gum produced a larger increase than placebo gum, the difference was not significant.     

The effect of xylitol and chlorhexidine acetate/xylitol chewing gums on plaque accumulation and gingival inflammation

Chewing gums may be suitable vehicles for the delivery of xylitol (X) and chlorhexidine acetate (CHX), both of which can aid oral health. The aim of this study was to determine the clinical effectiveness of chewing gums containing X or a combination of X and CHX in a double-blind, randomised, cross over, 5-day clinical trial, with a 9-day washout period in a group of participants over 40 years old. After professional tooth cleaning, 8 subjects (mean age 51.3+/-10.4 years) used in a random order 2 pieces of ACHX (a liquorice flavoured CHX/X) gum, 2 pieces of BCHX (a chocolate mint flavoured CHX/X), 2 pieces of X (a liquorice flavoured X gum) and 1 piece of ACHX. Gums were chewed 2x daily for 15 min and volunteers refrained from all other oral hygiene procedures. Data were analysed using Friedman nonparametric analysis of variance. Plaque indices for chewing 2 pieces of ACHX gum (0.78+/-0.15) and BCHX gum (0.52+/-0.15) were significantly lower (p<0.0006) than for X gum (1.57+/-0.08). The gingival index was significantly greater (p<0.05) for X containing gum than for the other chewing regimes. The subjects' attitudes to the gums were also assessed by structured questionnaires which showed that all gums were easy to chew, did not adhere to dentures, teeth or restorations and that the subjects preferred to chew 2 pellets rather than 1.     

Oral biochemical status and depression of Streptococcus mutans in children during 24- to 36-month use of xylitol chewing gum

Plaque and whole saliva samples were collected from initially 11- to 12-year-old children randomly chosen from two groups which participated in a 2- to 3-year field trial designed to test the efficacy of xylitol chewing gums in caries prevention. No initial differences were observed between the groups with regard to the plaque levels of Streptococcus mutans, but at the end of the 2-year xylitol gum regimen, the levels were smaller (p less than 0.05) in children using xylitol gum than in control children. In a similar follow-up study on children who were considered to be at high risk with regard to dental caries and who continued the study over a 3rd year, the xylitol-consuming subjects showed at the end of the study significantly smaller (p less than 0.004) salivary S. mutans counts than the control children. These effects were achieved after using up to 3 xylitol gums/day (daily xylitol dose per child was 7-10 g). Salivary flow rate and several salivary chemical parameters did not change.     

Long-term effect of xylitol gum use on mutans streptococci in adults

Many studies have shown the effects of chewing xylitol gum on mutans streptococci (MS) over short- and long-term periods in children; however, few studies have addressed long-term periods in adults. The objective of this investigation was to examine for 6 months the effects of chewing xylitol gum on MS in saliva and plaque in 127 adults (mean age 28.0 years). The participants were assigned to three groups according to gum type, in part taking preference for flavor into account and in part at random: xylitol (XYL), maltitol (MAL) and control (CR); 33, 34 and 27 subjects in each group, respectively, completed the trial. Daily gum use of the XYL and MAL groups was 7.9 and 7.1 g, respectively. MS levels, which declined significantly in saliva (p < 0.05) and plaque (p < 0.001) in the XYL group after 6 months, exhibited a significant increase in plaque in the MAL group (p < 0.001). Differences in relative changes of MS levels in plaque during the experimental period were significant between the XYL group and the CR (p < 0.05) and MAL groups (p < 0.001). Differences in relative change of amount of plaque during the experimental period were not statistically significant between the groups. The present study demonstrated that chewing xylitol gum for 6 months continued to inhibit the growth of mutans streptococci in adults.     

Effect of a fluoride-containing varnish on Streptococcus mutans in plaque and saliva

Abstract – The effect of topical application of a fluoride-containing varnish, Duraphat®, on the level of Streptococcus mutans in saliva and in dental plaque was investigated in schoolchildren. Samples of saliva and pooled buccal plaque were taken before varnish application and 4, 10 and 21 d after treatment. Fluoride varnish treatment with or without a preceding dental prophylaxis had no significant effect on the plaque and salivary levels of S. mutans. The findings suggest that the caries-reducing effect of fluoride varnish cannot be explained by an alteration of the incidence of 5. mutans in dental plaque or in saliva.