Effect of gum chewing on plaque accumulation

The purpose of this investigation was to test the effect of chewing gum sweetened with either sorbitol (LG) or sucrose (SG) on the growth of plaque on tooth enamel surfaces. Nineteen dental students, in a balanced crossover design, chewed the two gums for 5 days without normal oral hygiene practices. The control treatment was a 5-day non-chewing (NG) phase. A period of 9 days was allowed for normal hygiene between test phases. The chewing regimen required 20 minutes of use of one stick of chewing gum immediately after meals or snacks. The average number of sticks chewed was 3.8/day. Pre- and post-treatment plaque scores were recorded by two examiners using a Modified Navy Plaque Index (PLI) from 0 to 9 along each of four surfaces to assess six Ramfjord teeth. Pre-treatment mean PLI scores for the 3 test treatments were, NG = 2.0, LG = 1.9 and SG = 1.9. Post-treatment mean PLI scores were, NG = 3.6, LG = 3.3 and SG = 3.3. ANOVA of pre- and post-treatment scores revealed no significant differences between treatments. Post-treatment scores of the 2 chewing gums were then pooled, independent of sweetener. ANOVA of these data revealed chewing gum (LG + SG = 3.3) to cause significantly less plaque accumulation than no gum (NG = 3.6). In a no oral hygiene environment, plaque accumulation during use of sorbitol chewing gum or sucrose chewing gum was statistically the same. However, chewing gum, irrespective of sweetener, caused significantly less plaque accumulation than no chewing.     

Plaque growth while chewing sorbitol and xylitol simultaneously with sucrose flavored gum

In a recent study, sorbitol flavored chewing gum was found neither to increase nor decrease the normal rate of plaque formation, whereas high plaque scores were obtained with sucrose gum during 4 days of no mechanical tooth cleaning. The aim of the present study was to see if chewing sorbitol or xylitol flavored gum together with sucrose gum would affect the growth rate of plaque and whether chewing of xylitol flavored gum could reduce the amount of already formed plaque. Twenty-seven dental students refrained from mechanical oral hygiene measures from Monday to Friday morning for 3 weeks. The students were randomly divided into three groups. A three time crossed-over double-blind approach was used. During each test period one group chewed a combination of one piece sorbitol and one piece sucrose flavored gum five times per day, the second group correspondingly chewed xylitol and sucrose flavored gum, while the third group served as a no hygiene control group. After each test period the students in the control group chewed one piece of xylitol gum every 15 minutes for 2.5 hours. The participants started out each week with clean teeth and were at the end of each test period scored for visible plaque on the facial, mesial and lingual surfaces of their teeth. There was somewhat more plaque after 4 days of chewing sucrose-sorbitol and sucrose-xylitol gum combinations than after no oral hygiene alone. There was no difference between the two test treatments. The 2.5-hour chewing of xylitol flavored gum after the no oral hygiene period did not result in a reduction of the 4-day-old plaque.     

Prevention of plaque growth with chewing gum containing chlorhexidine acetate

The purpose of the study was to assess the anti-plaque effect of chlorhexidine (CHX) in chewing gum. The 0.80 g pieces of test gum contained 5 mg chlorhexidine acetate with or without a hydrogen peroxide releasing agent. The gum base with flavouring agents but containing neither CHX nor H2O2 was used as a control. 12 dental hygiene students volunteered to participate in the 3 x crossed-over double blind clinical trial. During the 4-day test periods, no other oral hygiene measures were allowed than chewing 2 pieces of gum at the time for approximately 10 min, 5 times daily. Between test periods, meticulous mechanical oral hygiene measures were practised for 3 days. At the beginning and at the end of each test period, the quantity of plaque was assessed using the plaque index, plaque wet weight, and the area of plaque on the tooth surface as criteria. The results indicated that both CHX gums completely inhibited the increase in plaque index and plaque weight. With regard to area of plaque, the difference between the 2 test gums and the control gum was less marked but still present. The test persons subjectively assessed the gum base to have a poor cleansing effect but also the least unpleasant taste. It was concluded that use of both the chlorhexidine gum and the gum-containing chlorhexidine in addition to the hydrogen peroxide releasing agent had an excellent plaque growth inhibiting effect during the 4-day test periods.     

Plaque-growth inhibiting effect of chewing gum containing urea hydrogen peroxide

The plaque-reducing effect of a chewing gum containing hydrogen peroxide was assessed. 12 dental hygienist students participated in a double-blind 3 x randomly crossed-over study. During the 4-day test periods, from Monday to Friday, no oral hygiene measures were allowed other than chewing 2 pieces of gum for approximately 10 min 5 x daily. The 800 mg pieces of gum were V6+regular (V6+) containing 0.4 g sorbitol and 6.3 mg hydrogen peroxide, V6 placebo gum (PLAC) containing 0.45 g sorbitol and no hydrogen peroxide, and only the gum base (GB) as a negative control. The quantity of plaque was assessed using the plaque index and the visible plaque index, and by scraping "all" plaque off the teeth in half the mouth during 2.5 min for determination of plaque wet weight. With all 3 measurements, chewing of the hydrogen peroxide-releasing gum (V6+) resulted in significantly lower plaque increments, from Monday to Friday, than chewing of the gum base (P less than 0.05). Chewing of the V6 placebo gum (PLAC) resulted in plaque scores which differed from neither those recorded after use of the hydrogen peroxide releasing (V6+) nor the placebo (GB) gums. The observed plaque-growth inhibiting effect of the hydrogen peroxide-releasing chewing gum in the present study was found to be of limited clinical significance.     

Effects of sugared and sugar-free chewing gum on the accumulation of plaque and debris on the teeth

Abstract The aim of this study was to determine the effects of sugar-free and sugar-containing gums on plaque formation, established plaque and salivary debris. Plaque accumulating during three 5-day periods was recorded in a group of 10 students who, in the absence of normal oral hygiene methods, chewed sugar-free or sugar-containing chewing gum or did not chew gum. In a second group of 10 students the effect of chewing the two types of gum on 3-day accumulations of plaque was recorded. Finally, the wet weight of liquorice debris present in saliva with and without gum chewing, was recorded. During the no chewing periods distinct and significant differences in the amounts of plaque accumulating at different sites were apparent. Both types of chewing gum significantly and comparably reduced plaque accumulation during the 5-day period. The chewing gums also significantly reduced established plaque on many tooth surfaces. Salivary debris was significantly reduced by 50% after chewing gum. It was noted that plaque removal occurred primarily from sites remote from the gingival margin and interdental areas and therefore it was concluded that the observed effects of chewing gum on plaque would not be reflected in a reduction in gingival inflammation.     

The effect of chewing xylitol gum on the plaque and saliva levels of Streptococcus mutans

Eating foods containing sucrose between meals can be highly cariogenic. The use of sucrose substitutes that provide the hedonistic appeal of sucrose, yet are not fermented by the plaque flora to the low pHs that are associated with caries, is a reasonable approach to caries control. Xylitol, a sweet-tasting pentitol, has been reported to cause about an 80% reduction in caries increment when chewed in a gum. The present investigation was designed to determine whether the chewing of xylitol gums affected the salivary and plaque levels of S mutans and lactobacilli. The chewing of xylitol gums for four weeks caused a significant reduction in saliva levels and plaque proportions of S mutans compared with pretreatment values. The levels were also significantly reduced to values obtained by chewing either sorbitol or fructose sweetened gum. The chewing of various gums had no significant effect on the proportions of lactobacilli in the plaque. These findings suggested that the small amounts of xylitol used (about 5 gm) resulted in a suppression of S mutans.     

Optimal dosage of chlorhexidine acetate in chewing gum

In a previous study, 800 mg pieces of sorbitol-flavored gum, each piece containing 5 mg chlorhexidine (CHX) acetate, when chewed 2 at the time 5 x daily, were found to have an excellent plaque growth inhibiting effect. The aim of Trial 1 of the present study was to assess whether chewing only 2 x daily, 2 pieces of the same concentration CHX gum for about 10 min would be as effective. 6 dental students participated in the 3 x randomly crossed over double-blind clinical trial. During the 5-day chewing periods, no other oral hygiene measures were allowed. The Hibitane Dental (HD) rinse was used as a positive and the gum base containing neither CHX nor the sweetening agent as a negative control. At the end of each test period, recordings were made for the plaque index (PII), the plaque wet weight (PWW) and the relative area of plaque covered tooth surface (plaque area %). Chewing of CHX gum twice daily inhibited plaque growth as effectively as the HD rinse. The aim of Trial 2 was to assess the antiplaque effect of lower concentration CHX gums with, hopefully, a less unpleasant taste. For this trial, 8 dental students were recruited to chew 2 x daily during 6-day periods two 800 mg pieces of sorbitol-flavored gum, each piece now containing either 5 mg, 4 mg or 3 mg CHX acetate. The effect of these dosages did not differ from the effect of the HD rinse.(ABSTRACT TRUNCATED AT 250 WORDS)     

麦芽糖醇口香糖对青少年牙菌斑的抑制效果

目的评价麦芽糖醇口香糖控制青少年牙菌斑集聚水平的临床效果。方法将30名13～15岁龋易感受试者随机分为A、B、C组,根据分组分别每天咀嚼麦芽糖醇口香糖、木糖醇口香糖、胶母基口香糖5次,每次10 min。采用改良Quigley-Hein菌斑指数记录法分别于基线、4周时检查受试者的菌斑指数情况。应用SPSS 17.0软件对数据进行统计分析。结果咀嚼口香糖4周后,3组受试者的菌斑指数都有明显下降,与基线相比的差异有统计学意义（P=0.000、0.000、0.006）;3组菌斑指数变化间的差异也有统计学意义（P=0.015）,组间两两比较结果表明,A组与B组菌斑指数变化间的差异无统计学意义（P=0.687）,而A组与C组、B组与C组菌斑指数变化间的差异有统计学意义（P=0.019、0.007）。结论麦芽糖醇口香糖对青少年牙菌斑的抑制效果与木糖醇口香糖相似。     

Prevention of sucrose-induced demineralization of tooth enamel by chewing sorbitol gum

Measurements were made of the effect of chewing sorbitol gum on the intra-oral demineralization induced by rinsing with 10% sucrose solutions. Blocks of bovine enamel were covered with a layer of Streptococcus mutans IB1600, and mounted on palatal appliances that were worn by five subjects for defined periods of time. Enamel demineralization was determined by following changes in iodide penetrability (delta Ip) of the enamel surfaces. Delta Ip increased to a maximum of about 15 units between 30 and 45 min, while the pH of the S. mutans plaque dropped to below 4 by 15 min. Plaque pH returned to 4.9 by 60 min. Chewing sorbitol gum after the sucrose rinse minimized further increases in delta Ip and brought about a more rapid return of the S. mutans plaque pH toward neutrality. The effect of chewing gum was greater when chewing was initiated earlier so that, when gum was given at five min after the sucrose rinse, demineralization was only 37% of that obtained without gum. The findings confirm earlier reports on the effect of gum on plaque pH, and directly demonstrate the profound protective effects that chewing sorbitol gum can have on tooth enamel.     

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.     

2种胶姆糖对菌斑pH值的影响

目的：观察咀嚼2种胶姆糖后口腔菌斑pH值的变化情况.方法：选择8例健康受试者（年龄23～27岁,男4例,女4例）参加3次试验,每次实验开始前停止刷牙24h,在使用10%的蔗糖溶液漱口前以及漱口后5、10、15、20min,用Beetrode pH微电极测量口腔菌斑的pH值,作为基线值.1周后先测量静息pH值,再用蔗糖溶液漱口,1min后给予无糖胶姆糖咀嚼,在5、10、15、20min时间点,分别测量非咀嚼侧的菌斑pH值.1周后重复上述实验,胶姆糖改为含茶多酚胶姆糖.应用SPSS10.0统计软件包对数据进行单因素方差分析和SNK分析.结果：与基线值比较,咀嚼2种胶姆糖都能有效防止由于含漱蔗糖水导致的菌斑pH值下降,并使pH值维持在静息pH值以上.2种胶姆糖之间无显著性差异（P＞0.05）.结论：咀嚼2种胶姆糖均能防止菌斑pH值下降,减少患龋危险.     

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.     

Effect on plaque growth of xylitol and sucrose-containing chewing gums

Two experiments tested the effects of xylitol or sucrose-containing chewing gums on plaque formation. In the first experiment the 18 subjects maintained their normal dietary habits, and in the second they received a sucrose-free diet during the 3-day experimental periods. Plaque formation was assessed gravimetrically and/or planimetrically. When the dietary habits were not altered, neither the sucrose nor the xylitol-containing chewing gums had significant effects on the plaque scores. When sucrose was almost eliminated from the diet, plaque formation was significantly higher in the sucrose than in the xylitol and the placebo groups. Although plaque formation was lower in the xylitol group than in the placebo group, the differences were not statistically significant.     

Sugar alcohols: what is the evidence for caries-preventive and caries-therapeutic effects?

The most widely used sugar alcohols are: xylitol, sorbitol, mannitol, maltitol, lactitol and the products Lycasin and Palatinit. It is often claimed that xylitol is superior to the other sugar alcohols for caries control. This paper examines clinical studies on the caries-preventive and therapeutic effects of sugar alcohols with emphasis on sorbitol and xylitol. It is concluded that chewing sugar-free gum 3 or more times daily for prolonged periods of time may reduce caries incidence irrespective of the type of sugar alcohol used. It may be sufficient to do this only on school days. Sucking xylitol-containing candies or tablets may have a similar effect as chewing xylitol chewing gum. Clinical trials suggest greater caries reductions from chewing gums sweetened with xylitol than from gums sweetened with sorbitol. However, the superiority of xylitol was not confirmed in 2 out of 4 clinical trials comparing the caries-preventive effect of xylitol- with sorbitol-sweetened gums. The caries-preventive effects of polyol-containing gums and candies seem to be based on stimulation of the salivary flow, although an antimicrobial effect cannot be excluded. There is no evidence for a caries-therapeutic effect of xylitol. These conclusions are in line with those of recent reviews and with the conclusions of the Scientific Committee on Medicinal Products and Medical Devices of the EU Commission.     

Fluoride and urea chewing gums in an intra-oral experimental caries model

The aim of the present investigation was to evaluate the effect of sugar-free chewing gums containing fluoride (F) and urea in an intra-oral experimental caries model. Placebo chewing gums (without any active ingredient) and no gum served as controls. Fifteen subjects participated in a cross-over, single-blind study. Demineralised enamel and dentine blocks were embedded in circular plastic discs and bonded to the buccal surfaces of the lower canines and first premolars. The discs were removed and analysed using transversal microradiography after each of the six 4-week periods during which the subjects used either test or placebo products or no product. The results revealed that frequent use of sugar-free chewing gum is sufficient to inhibit further demineralisation of previously demineralised enamel and dentine specimens in the oral cavity. Comparing F, urea and placebo gums, the data showed that there was little or no difference between the products, except for an inhibitory effect on the chewing side of the dentition after using F chewing gums.     

The effects of sugar-free chewing gums on dental plaque regrowth: a comparative study

Sugar-free chewing gum has been claimed to be a useful means of reducing dental plaque accumulation. The incorporation of additives, such as enzymes, abrasives and divalent metal ions, into gum formulations might improve their antiplaque activity, particularly at the buccal and lingual surfaces of the teeth. OBJECTIVES: The aim of this study was to investigate the plaque inhibitory effects of three sugar-free chewing gums each containing lactoperoxidase (LP), micro granules of silicon dioxide (SD), and zinc gluconate (ZG). METHODS: The study was an observer-masked, randomized cross-over design balanced for carryover effects, involving 12 healthy volunteers in a 4-day plaque regrowth model. An additive-free (AF) gum served as positive/negative control for occlusal and smooth surfaces, respectively. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced chewing their allocated product. Gum chewing was one piece chewed for 30min 4 times a day. On day 5, subjects were scored for disclosed plaque. RESULTS: There were no significant differences in antiplaque activity of the gums tested, neither for the smooth nor for the occlusal surfaces (P=0.447 and P=0.418, respectively). Similar results were obtained for the anterior and posterior sites of smooth surfaces (P>0.05), and for the lower and upper sites of occlusal surfaces (P=0.451 and P=0.53, respectively). CONCLUSIONS: These findings suggest that the chewing gums containing LP, SD and ZG would provide no plaque inhibitory effects on smooth surfaces. The gums containing these additives, therefore, should not be recommended as adjuncts to mechanical oral hygiene.     

Effect of xylitol and sucrose plaque on release of lysosomal enzymes from bones and macrophages in vitro

Plaque formed during a 5-day xylitol or sucrose chewing gum diet was used as an irritating agent in bone and macrophage culture. The release of hydrolytic enzymes was monitored. The contents of protein, DNA, and ATP were analyzed, to characterize plaque formed during different dietary periods. The release of glycosidases and phosphatases was lower in the presence of xylitol plaque when compared with sucrose plaque as an immediate reaction in macrophage cultures at 3 h and also in bone cultures at 3 days. The results indicate that xylitol plaque had a less irritating effect on macrophages and bones in vitro than sucrose plaque according to the parameters used in this study.     

Effect of sorbitol, xylitol, and xylitol/sorbitol chewing gums on dental plaque

The effect of sorbitol (SOR), xylitol (XYL), and the mixture XYL/SOR in chewing gums on dental plaque was studied in three groups of 7 adults (mean age 22.5 years). A fourth group of habitual users of sucrose-containing gums was used as a control. The study involved a 2-week, no-gum period followed by the use of the polyol gums for 2 weeks (10 gums/day in 5 2-gum doses). The daily consumption of XYL and SOR in the XYL and SOR groups was 10.9 g, whereas in the XYL/SOR group, 8.5 and 2.4 g of these polyols were used per day. At the end of the gum period the acidogenic response of the 48-hour plaque was tested using a 10-ml mouthrinse containing the polyols (10% w/v) present in the experimental gums, followed by a 10-ml rinse of 10% (w/v) sucrose solution. The plaque of the subjects who used XYL and XYL/SOR gums showed a significantly better ability to resist pH drops induced by the sucrose rinse than the plaque in the SOR gum group. No changes in resting pH values were observed in the XYL and XYL/SOR groups, whereas the use of SOR gum was associated with significantly lower pH values. The amount of plaque decreased in the XYL/SOR (24.3%) and the XYL (29.4%) groups, but increased in the SOR (48.3%) group, the changes in the SOR group differing significantly from those found in the other groups. The plaque and saliva levels of Streptococcus mutans generally increased in the SOR group, but decreased in groups which used XYL.     

Comparability and discriminating power of 4 plaque quantifications

Abstract This study was designed for analysis of the discriminating power of 4 different quantifications of supragingival plaque: (1) plaque wet weight (PWW); (2) the plaque index (PII); (3) the PLQ index measuring the coronal extension of plaque; (4) the area % of stained plaque. Different quantities of plaque were produced by adding chlorhexidine acetate (CHX), hydrogen peroxide (H₂O₂), or sucrose to experimental chewing gums. Total mean scores of 12 subjects in each of 3 test groups revealed that chewing of CHX gum resulted in the lowest plaque scores with all 4 quantifications and that the highest scores were recorded for the PWW or PII of the sucrose gum users. Chewing of the H₂O₂ gum produced as much plaque as the sucrose gum when evaluated according to the PLQ index and exceeded the sucrose gum scores when evaluated according to the area % index. The PWW discriminated best between low, medium and high plaque scores after chewing of both CHX, H₂O₂ and sucrose gums. PII scores 1 and 3 remained stable whereas the frequency of PII score 0 strongly decreased and that of score 2 strongly increased when going from gums producing low (CHX) and medium (H₂O₂) to large (sucrose) amounts of plaque. The PLQ index discriminated well between low and medium but poorly between medium and large amounts of plaque. The area % index functioned well when subjects with low (CHX) and medium (H₂O₂) plaque scores were subgrouped into those with <30%, 30–70% or > 70% of their tooth surfaces covered with stained plaque. After use of the sucrose gum, none of the 12 subjects exhibited area % scores in excess of 70%. Calculation of correlation coefficients between the 4 plaque quantifications revealed a strong correlation between PWW and PII, PWW and PLQ, and PII and PLQ recordings, whereas no significant correlation was found between PWW and area % recordings. It was concluded that the choice of a plaque quantification method is important for meaningful evaluation of clinical trials.     

Six-month polyol chewing-gum programme in kindergarten-age children: a feasibility study focusing on mutans streptococci and dental plaque

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.