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Aim: To evaluate the long-term outcome of a mother-child project in which mothers (n=173) with high counts of salivary mutans streptococci were randomly assigned to daily chewing gums containing xylitol (A), chlorhexidine/ xylitol/sorbitol (B), or sodium fluoride/xylitol/sorbitol (C) for one year, when the child was between 6 and 18 months., Methods: 140 of the off-springs were re-examined at the age of 10 years and 204 children of mothers with low counts of salivary mutans streptococci three months after delivery served as positive controls (D). Caries was scored in the young permanent dentition on enamel (noncavitated) and dentine (cavitated) levels., Results: The long-term attrition rate was 15%. The overall caries prevalence in the combined groups at 10 years of age was 31% (21% non-cavitated; 17% cavitated) with a mean DS of 0.7 (SD 1.3). No significant differences were found between the three experimental groups (A-C), or when compared with the control group. A statistically significant (p<0.05) positive relationship between the levels of salivary mutans streptococci at 18 months of age and the caries experience at the age of 10 years was disclosed for all groups combined., Conclusion: No beneficial longterm effects of maternal xylitol gum exposure on their children's dental health were demonstrated when compared with gums containing chlorhexidine and fluoride.

Purpose: The purpose of this study was to examine the effects of xylitol gum (XG) on the acquisition pattern of 39 bacterial species, including mutans streptococci (MS), in infants., Methods: Ninety-seven mothers (MS counts > 10(5) CFU/ml) were randomly divided into 4 groups and received: (1) XG (4.2 gm/day); (2) XG (6 months after baseline exams); (3) sorbitol gum (4.2 gm/day); or (4) no gum. Groups 1 and 3 chewed gum 3 times a day for 9 months. Microbiota of plaque and saliva samples from the mother-child pairs were analyzed by culturing and via checkerboard DNA-DNA hybridization., Results: MS was isolated from 33% of the predentate infant (< or =5 months old) baseline saliva samples and from 41% of the saliva and 65% of the plaque samples at the final visit. At baseline, positive responses to "mother's checking of baby's food temperature using baby's spoon" and "starting a bottle after stopping breast-feeding" were significant predictors (P = .009 and P < .001, respectively) of infant's total streptococci counts. At the final visit (9 months later), there were no significant differences between treatment groups for infants' 39 microbial plaque species, including MS., Conclusions: Maternal use of xylitol gum did not result in statistically significant differences in the microbial plaque composition of 9- to 14-month-old infants.

Background: The authors conducted a systematic review of original studies that was designed to assess the impact of polyol-containing chewing gum on dental caries compared with the effect with no chewing gum., Review Methods: The authors searched MEDLINE, The Cochrane Library and Google Scholar up to May 2008 to identify peer-reviewed articles that compared polyol-containing chewing gum with no chewing gum. The authors extracted study characteristics, data on incremental dental caries and quality by consensus. Data on prevented fraction (PF) were pooled across studies., Results: The results of 19 articles with data from 14 study populations showed that the use of xylitol, xylitol-sorbitol blend and sorbitol were associated with mean PF (95 percent confidence interval) of 58.66 percent (35.42-81.90), 52.82 percent (39.64-66.00) and 20.01 percent (12.74-27.27), respectively. For the sorbitol-mannitol blend, it was 10.71 percent (-20.50-41.93), which was not statistically significant. Sensitivity analyses confirmed the robustness of the findings., Clinical Implications: Although research gaps exist, particularly on optimal dosing and relative polyol efficacy, research evidence supports using polyol-containing chewing gum as part of normal oral hygiene to prevent dental caries.

Background: The multiple functions of saliva play a significant role in the prevention of dental caries., Methods: Chewing gum is known to stimulate salivary flow, and the results of studies of the role of stimulated saliva in the oral clearance of food particles, neutralization of dental plaque acids and reduction of the incidence of dental caries have been reported. The author reviews the results of these clinical caries trials., Results: Seven clinical trials have evaluated the impact of chewing gum on caries incidence. These studies have shown that chewing sugar-free gum after meals results in a significant decrease in the incidence of dental caries and that the benefit is due to stimulating salivary flow rather than any chewing gum ingredient., Conclusions: Stimulating salivary flow through the chewing of sugar-free gum after meals has been shown to reduce the incidence of dental caries., Clinical Implications: Practical measures for stimulating salivary flow after meals or snacks should be considered in caries prevention programs.

The aim was to evaluate the effect of xylitol and probiotic chewing gums on salivary mutans streptococci (MS) and lactobacilli (LB). The material consisted of 80 healthy young adults (21-24 years) who volunteered after informed consent. They were assigned by random into one of four parallel study groups: A, probiotic gum group; B, xylitol gum group; C, probiotic + xylitol gum group; and D, placebo gum group. The gums were taken three times daily after meals, and the intervention period was 3 weeks. The probiotic gums contained two strains of Lactobacilli reuteri (ATCC 55730 at a dose of 1 x 10(8) CFU/gum and ATCC PTA 5289 at a dose of 1 x 10(8) CFU/gum), and each pellet of the xylitol gum contained approximately 1.0 g xylitol as single sweetener. Pretreatment and posttreatment samples of stimulated whole saliva were collected and quantified for MS and LB with chair-side kits. A statistically significant reduction (p < 0.05) of salivary MS was displayed in group A and B after the intervention when compared with baseline. A similar but nonsignificant tendency was seen in group C. No alterations of salivary LB was demonstrated in any group. In conclusion, daily chewing on gums containing probiotic bacteria or xylitol reduced the levels of salivary MS in a significant way. However, a combination of probiotic and xylitol gums did not seem to enhance this effect.

Background: The author compared the caries-inhibitory action of sorbitol- and xylitol-sweetened chewing gum and assessed the role of these products in caries prevention., Types of Studies Reviewed: The author reviewed studies including randomized field trials with substantial numbers of participants and observational studies. He did not review case studies. He found studies through a MEDLINE search and by hand searching., Results: When compared with sugar-sweetened gum, sorbitol-sweetened gum had low cariogenicity [corrected] when it was chewed no more than three times per day. Xylitol-sweetened gum was noncariogenic in all of the protocols tested. Some studies claimed that xylitol-sweetened gum had an anticariogenic effect, though these claims need further study. There also is good evidence that when mothers of infants and young children chew xylitol-sweetened gum, it will block transmission of mutans streptococci from mother to child., Clinical Implications: The evidence is strong enough to support the regular use of xylitol-sweetened gum as a way to prevent caries, and it can be promoted as a public-health preventive measure. Chewing xylitol-sweetened gum, especially for patients who like chewing gum, can be fitted readily into a regimen that includes frequent fluoride exposure, good oral hygiene and regular dental appointments.

Aim: To investigate the use of polyol-containing chewing gums in a day-care centre (kindergarten) setting as a means to affect the growth of mutans streptococci and dental plaque., Design: Over a period of six months, 123 five-year-old children chewed xylitol (X group), sorbitol (G group), or did not chew gum (C group). Consumption of xylitol, and sorbitol was 4.5 to 5.0 g per day and subjects consumed in five supervised daily chewing episodes four at the day-care centres and one at home., Methods: Interproximal dental plaque was sampled at baseline and after six months for a laboratory study of mutans streptococci counts. The Quigley & Hein plaque index procedure was used. Interviews and questionnaires elucidated the acceptability of the programme., Results: Parents and kindergarten personnel regarded the programme as an important, additional procedure to promote better oral health. The children regarded the use of chewing gum as a pleasurable experience. Compared with groups G and C, there was a statistically significant reduction of mutans streptococci in the interproximal plaque in the X group. The Quigley & Hein plaque index scores tended to decrease in the X group, while no such trend was observed in the G group., Conclusions: Habitual use of relatively small daily quantities of polyol-containing chewing gum by young children may be regarded as an important additional caries-preventive procedure in a combined day-care centre and home setting. Especially xylitol-containing chewing gum may significantly reduce the growth of mutans streptococci and dental plaque which may be associated with dental caries.

The purpose of the study was to assess the outcome of school-based oral health education (OHE) and a sugar-free chewing gum program on the oral health status of children in terms of reduced caries increment and gingival bleeding over a period of 2 years. Nine primary schools randomly chosen from one district were divided into three groups: OHE group (Group E), sugar-free chewing gum in addition to OHE group (Group G), and the control group (Group C). All children of grade 1 (aged 6-7 years) were recruited (n = 1342). After 2 years, 1143 children remained in the study group at follow-up. The overall drop-out rate was about 15%. Data on dental caries and gingival bleeding were collected by clinical examination. The results showed that the mean increment of DMFS in Group G was 42% lower than in groups E and C (P < 0.05). The mean increments in F-S were higher in Groups G and E than in Group C (P < 0.01). The gingival bleeding scores were statistically significant among the three groups. Compared to Group C, the mean increment in bleeding scores of Group G was 71% lower (P < 0.01) and in Group E 42% lower (P < 0.05). The school-based OHE programs had some positive effect improving children's oral hygiene; in certain circumstances children may benefit from using polyol-containing chewing gum in terms of reduced dental caries.

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.

Objectives: The aim of this 3-year community intervention trial was to determine the caries preventive effect of sugar-substituted chewing gum among Lithuanian school children, and to assess compliance with the instructions for gum use., Methods: A total of 602 children, aged 9-14 years, from 28 school classes in five secondary schools in Kaunas, Lithuania, were given a baseline clinical and radiographic caries examination. The schools were randomly allocated to receive one of the following interventions: sorbitol/carbamide gum; sorbitol gum; xylitol gum; control gum; and no gum. Children in the four active intervention groups were asked to chew at least five pieces of gum per day, preferably after meals. The children were reexamined clinically after 1, 2 and 3 years, and radiographically after 3 years. Self-reported compliance was monitored anonymously four times during the study., Results: A total of 432 children were available at the 3-year clinical follow-up examination. The crude mean 3-year caries increments (DMFS--all stages of lesion formation) were 11.8 for the sorbitol/carbamide gum group; 9.0 for the sorbitol gum group; 8.1 for the xylitol gum group; 8.3 for the control gum group; and 12.4 for the no gum group. The adjusted 3-year caries increments were statistically significantly lower in the sorbitol gum group, the xylitol gum group and the control gum group than in the no gum group, whereas no statistically significant difference was seen between the no gum group and the sorbitol/carbamide gum group. Adjusted 3-year caries increments in the xylitol gum group and the sorbitol gum group did not differ statistically significantly from the caries increments in the control gum group. Compliance with the study protocol was better in School C (xylitol gum) than in the other schools. In all schools, compliance decreased over time., Conclusion: The results indicate that the caries preventive effect of chewing sugar-free gum is related to the chewing process itself rather than being an effect of gum sweeteners or additives, such as polyols and carbamide.

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.

The objective of this investigation was to evaluate the effect on dental caries experience of using carbamide polyol chewing gum as a supplement to standard oral hygiene procedures for schoolchildren in a developing country (Madagascar). In 1994, grades 1 and 4 children of demonstration schools were allocated to experimental and control groups; all children participated in a school-based oral health education programme, including daily toothbrushing supervised by the classroom teacher. At grade 1, the test group (n = 125) also used chewing gum (V6: 55.5 per cent sorbitol, 4.3 per cent xylitol, 2 per cent carbamide) three times a day. At grade 4, one test group (n = 177) had chewing gum three times a day and an additional test group (n = 74) had chewing gum five times a day. The control groups included 117 children at grade 1 and 209 at grade 4. Dental caries was registered in 1994 and 1997 according to the Recording System for the Danish Child Dental Services. In grade 1 children, the preventive effect of the total DMFS was not statistically significant except for occlusal caries (-0.65 DMFS, P < 0.01). In the grade 4 test groups, non-significant reductions of dental caries experience were found when compared with controls. The present community trial indicates that the use of polyol chewing gum may be considered a supplement to the control of occlusal dental caries in young primary schoolchildren, particularly in developing countries with limited resources for dental care.

Habitual xylitol gum-chewing may have a long-term preventive effect by reducing the caries risk for several years after the habitual chewing has ended. The goal of this report was (1) to determine if sorbitol and sorbitol/xylitol mixtures provide a long-term benefit, and (2) to determine which teeth benefit most from two-year habitual gum-chewing - those erupting before, during, or after habitual gum-chewing. Children, on average 6 years old, chewed gums sweetened with xylitol, sorbitol, or xylitol/sorbitol mixtures. There was a "no-gum" control group. Five years after the two-year program of habitual gum-chewing ended, 288 children were re-examined. Compared with the no-gum group, sorbitol gums had no significant long-term effect (relative risk [RR], 0.65; 95% confidence interval [c.i.], 0.39 to 1.07; p < 0.18). Xylitol gum and, to a lesser extent, xylitol/sorbitol gum had a long-term preventive effect. During the 5 years after habitual gum-chewing ended, xylitol gums reduced the caries risk 59% (RR, 0.41; 95% c.i., 0.23 to 0.75; p < 0.0034). Xylitol-sorbitol gums reduced the caries risk 44% (RR, 0.56; 95% c.i., 0.36 to 0.89; p < 0.02). The long-term caries risk reduction associated with xylitol strongly depended on when teeth erupted (p < 0.02). Teeth that erupted after 1 year of gum-chewing or after the two-year habitual gum use ended had long-term caries risk reductions of 93% (p < 0.0054) and 88% (p < 0.0004), respectively. Teeth that erupted before the gum-chewing started had no significant long-term prevention (p < 0.30). We concluded that for long-term caries-preventive effects to be maximized, habitual xylitol gum-chewing should be started at least one year before permanent teeth erupt.

To determine the effect of chewing sugar-free gum on caries incidence, the authors conducted a randomized clinical study. A total of 1,402 children in Puerto Rico, in grades 5 through 7 at baseline, completed the study. They were randomized by classroom into a control group or chewing gum group; those in the gum group were instructed to chew sugar-free gum for 20 minutes after each of three meals a day. Clinical and radiographic evaluations were performed at baseline and after two and three years. The results show that all subjects and high-risk subjects, respectively, in the gum group developed 7.9 percent and 11.0 percent fewer decayed, missing or filled surfaces than subjects in the control group. Based on these findings, the authors concluded that chewing sorbitol-based sugar-free gum after eating significantly reduces the incidence of dental caries.

The aim of this study was to test the hypothesis that the chewing of xylitol- or xylitol/sorbitol-containing chewing gum reduces plaque formation and the acidogenic potential of dental plaque. Thirty healthy volunteers aged from 19 to 28 yrs were randomly allocated to one of three test groups, chewing either xylitol-, xylitol/sorbitol-, or sucrose-sweetened gums. A three-day plaque accumulation period of no oral hygiene was instituted prior to and at the termination of the chewing gum program, which lasted 33 days. Plaque quantity was assessed on the basis of protein content of individual plaque samples collected by a standardized technique. Acidogenic potential of individual baseline and test plaque samples was assessed by the quantity of various organic acids formed from D-(U-14C)glucose. Identification of extracellular and intracellular metabolites was performed by HPLC. Statistical evaluation of data was performed according to paired comparisons of individual baseline and post-chewing data. Plaque formation, acidogenic potential, and glycolytic profiles were similar at baseline and after the gum-chewing periods. Also, there was no intracellular accumulation of glycolytic metabolites within the plaque bacteria to indicate the inhibition of glycolysis. The study thus leads to the conclusion that, in young adults with low caries experience, exposure of the oral cavity to acceptable doses of xylitol or xylitol and sorbitol has no effect on the microbial deposits on the teeth.

A previous clinical trial showed that long-term use of saliva-stimulating polyol (xylitol and sorbitol) chewing gums was associated with arrest of dental caries in young subjects. After a 20-22-month intervention (when the subjects were 8 years old), a total of 23 primary teeth with extensive dentin caries lesions whose surface in clinical examination was found to be totally rehardened (remineralized) could be removed because the teeth were near their physiologic exfoliation time. These teeth were subjected to histologic, microhardness, and electron microscopic tests. The majority of the specimens had been remineralized from the surface by a non-cellular-mediated process within the remaining collapsed, organic extracellular matrix associated with the remaining dentinal surface. Many of the underlying dentinal tubules were filled with a matrix that had been subsequently mineralized. Dental microanalyses showed that the topmost (outer) 20-microm-thick rehardened layer of the lesions exhibited the highest Ca:P ratio, which leveled off at a depth of approximately 150 microm. The rehardened surface layer (normally <0.1 mm in thickness) was significantly (P < 0.001) harder than sound dentin and nearly as hard as sound enamel. Although the main source of the mineral present in the rehardened layer was most likely of salivary origin, some extracellular remineralization was probably mediated by odontoblasts. The results complete the dinical diagnoses of the original trial and suggest that regular use of polyol chewing gums may induce changes in dentin caries lesions, which in histologic and physiochemical studies show typical characteristics of rehardening and mineralization.

The prevalent use of chewing gum has prompted interest in its dental effects. Important defining aspects are the ability to use sugar substitutes in gum manufacture and the prolonged stimulation of a protective flow of saliva. The main sugar substitutes used are sorbitol and xylitol. Because it is not fermented by oral bacteria, xylitol is considered to be non-cariogenic, and while sorbitol in solution can be fermented slowly by mutants streptococci, chewing sorbitol-sweetened gum does not cause a fall in plaque pH. Effects of chewing sugar-free gum on the ability of plaque to form acid from sucrose are equivocal, although the tendency is for the plaque acidogenicity to be reduced with the use of xylitol gum for 2-3 weeks, due to its inhibitory effects on mutants streptococci. Gum-chewing also stimulates a protective salivary flow when used after an acidogenic stimulus, and may enhance salivary function, especially in subjects with low flow rates. Sorbitol and xylitol gums have similar beneficial effects in promoting enamel remineralisation in short-term in-situ experiments. Clinical trials indicate that xylitol gum has a useful anticaries role, superior to the effects of sorbitol gum. In conclusion, both sorbitol and xylitol chewing gums are non-cariogenic in contrast to sugared gum, and exhibit beneficial anticaries properties through salivary stimulation. In addition, xylitol's antibacterial properties seem likely to lead to caries reductions superior to the more modest reductions with sorbitol gum.

A double-blind 3-treatment crossover design employing a 6-day trial period with out mechanical oral hygiene measures was used to compare dental plaque formation following use of chlorhexidine (CHX) acetate-, xylitol-, and sorbitol-containing chewing gum. Fourteen dental students were assigned a random ordering of the chewing gum products and received professional tooth cleaning at the start of trial periods. For each trial period, subjects were instructed to use 5 pieces of the unlabeled chewing gum daily (containing 5.0 mg CHX acetate/piece; 0.8 xylitol/piece; or 1.0 g sorbitol/piece). Two pieces of chewing gum were used following each morning and evening meal and one piece following the noon meal. The subjects were instructed to use the products for 20 minutes at each occasion. A 7-day washout-period between trial periods was used. The Turesky modification of the Quigley and Hein index was used to assess plaque formation. Differences between treatments were evaluated using a repeated measures ANOVA with Newman-Keuls multiple comparisons. The CHX-containing chewing gum showed significantly reduced plaque values (0.7 +/- 0.4) compared to the sorbitol-(2.7 +/- 0.4; P < 0.01) and xylitol-product (1.7 +/- 0.3; P < 0.01). Furthermore, the CHX-product significantly reduced plaque levels compared to the study subjects' regular plaque control routines (1.3 +/- 0.04; P < 0.05). The xylitol-product exhibited significantly lower plaque-values than the sorbitol-product (P < 0.01). Our results suggest that regular use of CHX-containing chewing gum appears useful to control dental plaque formation.

The effect of 2-year chewing-gum use on the caries rates of primary teeth was studied in a combined school and home program in a sample of 510 initially 6-year-old subjects with high caries experience, low availability of fluoride, and difficult access to dental care. The gum, formed into either sticks or pellets, comprised either xylitol, sorbitol, or mixtures thereof. The gum was chewed for 5 min under supervision five times a day during the school year, and for variable times during nonschool days. Seven groups were studied. One group received no gum; two xylitol gum groups received either pellet or stick gum as did, two sorbitol gum groups, and two groups received either of two types of xylitol/sorbitol pellet gum. The response variable was the development of a frank carious lesion detectable by physical loss of enamel and probable extension to the dentin for those surfaces of primary teeth that were not cavitated at baseline. Caries rates associated with the use of each of the gum types were compared to the caries rates in the no-gum group. The usage of all polyol gums resulted in a significant decrease of the caries onset rate (p < 0.05). The caries onset risk for a primary surface in the xylitol pellet and the sorbitol pellet groups was 35 and 44% of that in the no-gum group (relative risk, 0.35; 95% confidence interval, 0.21-0.59; relative risk, 0.44; 95% confidence interval, 0.30-0.63, respectively). The caries onset risk in the xylitol stick gum group was 53% of that in the no-gum group (relative risk, 0.53; 95% confidence interval, 0.39-0.72), which was marginally (p = 0.1520) lower than in the sorbitol stick gum group (relative risk, 0.70; 95% confidence interval, 0.52-0.94). The usage of both xylitol/sorbitol mixtures in pellet form was associated with a caries onset rate comparable with the usage of the xylitol stick gum. The largest caries risk reduction was observed in the group receiving xylitol pellet gum.

Dental caries is a pandemic infectious disease which can affect the quality of life and consumes considerable health care resources. The chewing of xylitol, sorbitol, and even sugar gum has been suggested to reduce caries rates. No clinical study has simultaneously investigated the effectiveness of these gums when compared with a group receiving no chewing gum. A 40-month double-blind cohort study on the relationship between the use of chewing gum and dental caries was performed in 1989-1993 in Belize, Central America. One thousand two hundred and seventy-seven subjects (mean age, 10.2 years) were assigned to nine treatment groups: one control group (no supervised gum use), four xylitol groups (range of supervised xylitol consumption: 4.3 to 9.0 g/day), two xylitol-sorbitol groups (range of supervised consumption of total polyols: 8.0 to 9.7 g/day), one sorbitol group (supervised consumption: 9.0 g/day). The gum use during school hours was supervised. Four calibrated dentists performed the caries registrations by means of a modified WHO procedure. The primary endpoint was the development of an unequivocal caries lesion on a non-cavitated tooth surface. Compared with the no-gum group, sucrose gum usage resulted in a marginal increase in the caries rate (relative risk, 1.20; 95% confidence interval,0.96 to 1.49; p = 0.1128). Sorbitol gum significantly reduced caries rates (relative risk 0.74; 95% confidence interval, 0.6 to 0.92 ; p = 0.0074). The four xylitol gums were most effective in reducing caries rates, the most effective agent being a 100% xylitol pellet gum (relative risk, 0.27; 95% confidence interval, 0.20 to 0.36; p = 0.0001). This gum was superior to any other gum (p < 0.01). The xylitol-sorbitol mixtures were less effective than xylitol, but they reduced caries rates significantly compared with the no-gum group. DMFS analyses were consistent with these conclusions. The results suggest that systematic usage of polyol-based chewing gums reduces caries rates in young subjects, with xylitol gums being more effective than sorbitol gums.

Sixty 11- to 15-year-old children wearing fixed orthodontic appliances were given chewing gums containing polyol for daily use after meals and snacks, to study whether the chewing of gums that contained slowly fermentable polyols (xylitol and sorbitol) affects the amount of dental plaque and the number of mutans streptococci present in plaque and saliva. The 60 subjects were randomly divided into four groups, each of which was provided with a supply of 1.35 gm pellet-shaped gums for a period of 1 month, as follows: (1) xylitol; (2) sorbitol; (3) xylitol-sorbitol mixture I (3:2); and (4) xylitol-sorbitol mixture II (4:1). In each group, two pellets with a total initial gum mass of 2.7 gm (maximum polyol dose per day: 10.5 gm), were used six times a day. The fresh and dry weight of dental plaque, collected at baseline and 28 days later from incisors, canines, and premolars from the area between gingival margin and the bracket, reduced in all groups, but most significantly (by 43% to 47%) in children receiving xylitol gum. The plaque and saliva levels of mutans streptococci did not change in the sorbitol group, but was significantly (in most cases) reduced by 13% to 33% in groups that received gum containing xylitol. Provided that the quantity of dental plaque and the plaque and salivary levels of mutans streptococci can be regarded as risk factors in dental caries, these results suggest that regular use of polyol gum--and especially gum that contains xylitol as the predominant sweetener--can reduce the caries risk in young patients wearing fixed orthodontic appliances.

The purpose of this paper is to report clinical observations on the stabilisation of dentine caries in two chewing gum studies carried out in young subjects. One study focused on the permanent dentition of 1,277 initially 10-year old subjects, while the other study was carried out on 510 initially 6-year old subjects and focused on the primary dentition. In both trials, several chewing gum formulas containing dietary polyols (xylitol and sorbitol, or their combinations) were used for up to 40 months (10-year olds) or up to 24 months (6-year olds). The daily consumption level of both polyols was up to 10.7 g per subject, used normally in 5-minute chewing episodes 3 to 5 times per day. Supervised chewing in schools lasted 5 min per episode, and for variable times during non-school days. Rehardening of dentine caries lesions was observed clinically by experienced, blinded examiners using sharp dental explorers and fibre optic light. After 40 months (permanent dentition) or after 18 months (primary dentition), rehardening (caries arrest) generally occurred more frequently in subjects who used polyol gums than in subjects who did not receive gum as part of the programmes, or who received sucrose gum. Arrest or non-progression of dentine caries was most frequently observed in subjects who used 100 per cent xylitol gums or mixtures of xylitol and sorbitol, but the differences between gums were not consistently significant. However, the usage of 100 per cent xylitol pellet-shaped gum was more frequently associated with arrest of dentine caries than other treatments. These results and previous studies suggest that high-xylitol chewing gum usage can retard or arrest even rampant dentine caries in conditions where effective restoration and prevention programmes have not been instituted, and can also provide additional protection against further caries development during full implementation of restorative procedures by holding the lesion in a non-progressive condition.

Intra-oral remineralisation of experimental caries-like lesions in human enamel, as determined by polarised light microscopy and quantitative microradiography, was promoted to a similar extent (% fall in delta Z, 18.6 and 19.0) by chewing a sorbitol or sorbitol/xylitol (3:1)-sweetened gum for 20 min after each of three meals and two sugary snacks daily. The results suggest that reported differences in the properties of the two sweeteners do not affect their ability to enhance remineralisation due to salivary stimulation.