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.     

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.     

Clinical study to evaluate the effects of three marketed sugarless chewing gum products on plaque pH, pCa, and swallowing rates

The purpose of this study was to determine the ability of three commercially available chewing gums (Extra, Trident, and CareFree) to stimulate saliva flow and reverse the plaque acid and ionized calcium levels induced by a glucose challenge. Electrodes to measure pH and pCa were situated in a Hawley appliance. When the Hawley appliance was in place, the electrodes were inserted into three day old plaque at maxillary interproximal sites. A pressure sensor, located in the posterior center of the Hawley appliance, was used to record swallowing rates. After baseline values were determined, the test procedure consisted of first administering a 5% glucose challenge solution followed by a 10 minute challenge effect period, a 5 minute gum chewing or product period, and finally a 10 minute product effect period after the test gum was discarded. An ANOVA was used to compare the ability of each chewing gum to stimulate saliva and cause a return of the plaque acid and/or ionized calcium to baseline levels following product discard. The three chewing gum products varied in both time and level of pH attained while neutralizing plaque acidity (p less than .05) induced by the glucose rinse. No significant differences were found between the chewing gums for the pCa data and swallowing rates. All chewing gum products stimulated swallowing and effectively reversed plaque pH and pCa changes caused by the glucose rinse.     

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.     

Growth of plaque while chewing sucrose and sorbitol flavoured gum

The aim of the study was to assess the claimed toothcleansing effect of sorbitol and sucrose flavoured chewing gums. A total of 24 dental students participated in a double-blind, four times crossed over clinical trial during which each student chewed both types of gum for 4 days each. No other means to clean the teeth were allowed during the test periods. Two 4-day periods of no oral hygiene and no chewing were used as controls indicating the normal growth rate of plaque. The results confirmed earlier observations that sorbitol flavoured gum does neither increase or decrease plaque formation. Chewing of sucrose gum, however, was found to promote the growth rate of plaque. The cleansing effect of the gums was also tested on the plaque formed during the 4-day no-oral-hygiene periods. In this part of the study the chewing of 10 pieces of sorbitol flavoured gum during a time period of 3 h did not significantly reduce the plaque scores, while the sucrose flavoured gum, correspondingly used, again resulted in a statistically significant increase in the amount of bacterial deposits. Because of the rapid reaction of the plaque to sucrose flavoured gum, so-called sugarless substitutes were recommended for those who insist on chewing.     

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.     

咀嚼口香糖对含漱蔗糖溶液后牙菌斑原位pH值的影响

目的：观察咀嚼含糖口香糖和含木糖醇口香糖对牙菌斑原位pH值变化的影响。方法：选择10名健康青年志愿者，采用受试者自身对照的临床试验方法，分别检测受试者含漱蔗糖溶液后咀嚼含糖口香糖和含木糖醇口香糖50min内牙菌斑pH值的动态变化。牙菌斑原位pH值的测定采用pH微电极接触法在口内直接测量。结果：含漱蔗糖溶液后5min开始咀嚼口香糖20min，可以明显提高牙菌斑pH值，使pH较快恢复至静止水平。咀嚼初期使用含糖口香糖牙菌斑pH无明显变化，而使用含木糖醇口香糖在咀嚼初期就可以明显提高牙菌斑pH至7．30。结论：含漱蔗糖溶液后，咀嚼无糖口香糖对牙菌斑的酸性产物产生明显的缓冲作用，提高菌斑pH值的作用较咀嚼含糖口香糖迅速而有效。     

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.     

Effect of sorbitol sweetened breath mints on salivary flow and plaque pH in xerostomic subjects

The purpose of this study was to assess the effect of a sorbitol sweetened breath mint on salivary flow and plaque pH in subjects suffering from xerostomia. The breath mints effectively increased whole and parotid salivary flow rates during a 10-minute test period. Additionally, the mints reduced the acidogenic effect of a 10% sucrose rinse, as measured by changes in plaque pH. This change was presumably caused by the sialogogic action of the mints. The efficacy of sorbitol sweetened breath mints as a palliative, and possibly therapeutic aid for individuals with xerostomia compares favorably with the results of an earlier study similarly testing the effects of sorbitol sweetened chewing gum.     

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。     

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.     

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.     

In vivo measurements of sulcal plaque pH after topical applications of sorbitol and sucrose in rats fed sorbitol or sucrose

To test whether adaptation to sorbitol could be observed in rat plaque, we made pH measurements of rat sulcal plaque in vivo, following topical application of 10% sorbitol solution. Rat pups were inoculated orally with S. mutans 6715 and fed diet MIT 305 (5% sucrose) for 16 days. Baseline sulcal plaque pH response of these rats to topical application of 10% sorbitol solution was measured. One group of 16 rats was then fed 20% sucrose in the diet, and a second group 20% sorbitol. After 13 days' feeding of the experimental diets (four days were used for accommodation to dose, and nine days at the 20% level for sorbitol), there was a significantly greater (p less than 0.01) drop in pH following topical application of 10% sorbitol in this group than in the sucrose-fed group. There was no difference in the pH response of the two groups to topical application of a 10% sucrose solution when tested six days later. The sulcal enamel caries score was significantly higher (p less than 0.001) in the sucrose group, but buccal enamel scores were similar in both groups. Adaptation in rat plaque took place, and could be measured in vivo as an increased drop in sulcal plaque pH following topical application of sorbitol. It is not clear whether this adaptation was primarily due to selection of sorbitol-fermenting micro-organisms, or, more likely, by induction of sorbitol-specific enzymes. Relative to the sucrose-containing diet, the sorbitol diet was hypocariogenic, even under experimental conditions.     

咀嚼麦芽糖醇口香糖对牙菌斑原位pH值的影响

目的探讨咀嚼麦芽糖醇口香糖后牙菌斑原位pH值的变化趋势。方法将30名13～15岁龋易感儿童随机分为3组，即麦芽糖醇口香糖组（A组）、木糖醇口香糖组（B组）、胶母口香糖组（C组）。通过微电极原位接触法对牙菌斑pH值进行检测，观察咀嚼口香糖4W前后菌斑pH值的变化趋势。结果三组受试者分别在咀嚼口香糖后，菌斑pH值于各个时间点均呈上升趋势，约20min达到最高值，随后仍保持高于基线值水平。咀嚼口香糖4周后，三组各时间点牙菌斑pH值均上升，与咀嚼前比较具有显著性差异（P〈0．05）；三组间在各个时间点pH值上升幅度（△pH）比较具有显著性差异（P〈0．05）。结论麦芽糖醇口香糖对牙菌斑pH值的作用同木糖醇口香糖一样较为明显。     

In vivo measurements of sulcal plaque pH in rats after topical applications of xylitol, sorbitol, glucose, sucrose, and sucrose plus 53 mM sodium fluoride

In two series of experiments, Sprague-Dawley-derived rats were infected orally with cariogenic micro-organisms and fed caries-promoting diets. By means of an antimony electrode, resting pH values were measured in the mesial sulcus of the maxillary left first molar. 100 or 200 microL of the test solutions were applied, and the change in pH (delta pH) was recorded for three min. Test solutions were: (a) 10% sucrose, 10% glucose, 10% sorbitol, or 10% xylitol; (b) 0%, 10%, 20%, or 40% sucrose; (c) 0%, 3%, 7%, or 10% sucrose; and (d) 10% sucrose, 10% sucrose + 53 mmol/L NaF (1000 ppmF-), or 10% sucrose + 53 mmol/L NaCl. Experimental design was a 4 X 4 Latin square (a, b, c) or a cross-over design (d). Solutions of sucrose and glucose gave significantly greater decreases in pH than did sorbitol or xylitol. pH fall was maximal for 10% sucrose and significantly less for 40% sucrose during the three-minute experimental period. For sucrose solutions ranging in concentration from 3 to 10%, pH fall was highest after application of 10% sucrose when plaque was previously rinsed with water, but this pH fall did not differ significantly from that obtained using a 7% sucrose solution. Adding 1000 ppmF- to a 10% sucrose solution caused an increase in pH. Rinsing the teeth to remove saliva resulted in significantly lower resting pH values. The results of these experiments are in agreement with the results of human plaque pH measurements.     

Influence of short-term sucrose exposure on plaque acidogenicity and cariogenic microflora in individuals with different levels of mutans streptococci

The aim was to study the short-term effect of a varying sucrose exposure on plaque acidogenicity and cariogenic microflora in two groups of subjects with different levels of mutans streptococci (MS). Eight subjects with low (<10(4)) and 8 with high (>10(6)) numbers of MS per millilitre saliva participated. Three 7-day test periods were conducted. During two of these, the subjects rinsed either 5 or 10 times daily with 10% sucrose; the third period without any mouth rinses served as control. The subjects refrained from oral hygiene during the last 3 days of each test period. On day 7, the following parameters were measured: plaque pH after a sucrose rinse, numbers of MS, Streptococcus sanguis and lactobacilli in saliva, percent MS in plaque and plaque index. The results revealed that plaque acidogenicity was more pronounced for the high-MS group compared to the low-MS group after all three test periods, i.e. lower resting pH, deeper pH falls and a lower final pH. For both groups, the greatest pH-lowering capacity of plaque was found after the period with 10 sucrose rinses/day. An increase in bacterial counts was noted for both groups during the test periods with the 5- and 10-time rinse regimen; this increase was larger for the high-MS group compared to the group with low MS counts. The highest plaque index was, irrespective of the test period, found for the high-MS group.     

The efficacy of a fluoride chewing gum on salivary fluoride concentration and plaque pH in children

OBJECTIVES: The purpose of this study was therefore to study the influence of different chewing times on the salivary F concentration and on the recovery of plaque pH directly after a sucrose rinse on both the chewing and the non-chewing side. METHODS: For this purpose, one piece of sugar free chewing gum was chewed to 10 healthy subjects (aged 8-10 years, 5 male and 5 female children). Subjects refrained from toothbrushing for 3 days. On the fourth day, they rinsed for 1 min with 10 microl of a 10% sucrose solutions. After 8 min, chewing gum was given and started to chew for either 5, 10, 20, 30, 45 min or control (sucrose rinse). Thus, altogether six test sessions were repeated at one week intervals. Measurements of F concentration in saliva and pH of approximal plaque were carried out at two contralateral sites for up to 60 min. RESULTS: Higher salivary F concentrations were found on the chewing side than on the non-chewing side (expressed as) (p<0.05). But, the difference between the chewing and the non-chewing side was not obvious for the plaque pH (expressed as AUC) (p>0.05). Therefore, this study showed that: (1) the F concentrations in saliva after chewing a F containing chewing gum had only small numerical differences among the various chewing times, with the exception for 5 min. All chewing time periods showed statistically significant differences between chewing and non-chewing side. (2) The prolonged chewing time increased the plaque pH recovery after a sucrose rinse (p<0.05) but there was no statistically significant difference on both of the chewing and non-chewing side (p>0.05). CONCLUSION: The results of this study indicated that a prolonged chewing time was favorable to the plaque pH recovery after a sucrose rinse and, to a certain extent, to the salivary fluoride concentration. Also it was shown that the F concentration in saliva was strongly dependent on which side the subject chewed on.     

Effects of frequent mouthrinses with palatinose and xylitol on dental plaque

The aim was to evaluate the effects of frequent mouthrinses with palatinose, xylitol and a mixture of palatinose and xylitol on plaque pH, plaque formation and cariogenic microorganisms. 15 subjects refrained from toothbrushing during 3 test periods and rinsed 15 × daily for 4 d with 10 nil of: (1) 50% palatinose, (2) 37.5% palatinose+ 12.5% xylitol, or (3) 50% xylitol. A contrast period with no mouthrinses was also carried out. The 4 periods were carried out in a randomized order with a cross–over design. After the 4–day periods, 3 parameters were measured: (1) plaque pH during the first 30 min after a mouthrinse with palatinose, a mixture of palatinose and xylitol or xylitol alone, directly followed by a 2nd rinse with 10% sucrose; (2) number of mutans streptococci and lactobacilli in plaque and saliva; (3) plaque index. The most pronounced pH drop for the sugar substitutes was found when rinsing with 50% palatinose after the palatinose period, and the least pH drop with 50% xylitol after the xylitol period. The sucrose rinse gave similar pH fall after all 4 periods. The microbial data showed no differences between the 4 periods, but the mutans streptococcus counts in saliva decreased after the xylitol period in contrast to the 3 other periods. Regarding the plaque index, xylitol gave lower scores compared to the other 3 periods.     

Effect of xylitol-containing chewing gums on interdental plaque-pH in habitual xylitol consumers

OBJECTIVE: The aim was to investigate the effect of high and low amounts of xylitol on the interdental plaque-pH, directly and after sucrose challenge, in schoolchildren with habitual consumption. MATERIAL AND METHODS: The study group consisted of 11 healthy children (10-15 years) with low caries risk and the experiment had a single-blind crossover (Latin square) design. After a 2-week run-in period with a daily 4.0 g xylitol intake, the children were subjected to single-dose exposures of chewing gums with (i) paraffin (CTR; no xylitol), (ii) low-dose xylitol (LX; 2.0 g xylitol), and (iii) high-dose xylitol (HX; 6.0 g xylitol) in a randomized order separated by a washout period of 1 week. Samples of chewing-stimulated whole saliva were collected prior to and after the experimental period for determination of bacterial counts. The outcome measures were in situ plaque-pH (micro-touch method) and area under the pH curve (AUC). RESULTS: The AUC was significantly greater (p < 0.05) in the HX group compared to the LX and control groups during the first 5 min after chewing. After a 10% sucrose rinse, the interdental plaque-pH dropped in all groups but the HX regimen displayed significantly less reduction 0-5 min after chewing (p < 0.05). No significant alterations of the total viable counts or mutans streptococci levels in saliva were disclosed during the 4-week experimental period. CONCLUSIONS: The present results suggested that a high single dose of xylitol had a short and limited beneficial effect on interdental plaque-pH in habitual xylitol consumers, while a low single dose, resembling normal chewing gum use, did not differ from the control.     

The effect of a dentifrice containing chlorhexidine and zinc on plaque, gingivitis, calculus and tooth staining

Abstract. In this 6 months randomized, stratified double-blind parallel study, plaque, gingivitis, calculus formation and tooth staining were assessed in 208 participants. The participants either used a 0.12% chlorhexidine rinse and a gum care dentifrice (positive control) or a placebo rinse and the gum care dentifrice (control) or the placebo rinse and an experimental dentifrice containing 0.4% chlorhexidine and 0.34% Zn²⁺ (experimental group). After 6 months product use, all groups had less plaque, less gingivitis and all developed calculus and tooth staining. For the positive control group and for the experimental group, significant reductions in plaque and gingivitis (gingival index and number of bleeding sites) were seen compared with the control group. Significantly more calculus developed in the positive control group, while the experimental group was not different from the control group. Finally, tooth staining was significantly higher for the groups using chlorhexidine containing products compared with the control group. The experimental dentifrice users however did develop significantly less staining compared with the positive control. It is concluded that the experimental dentifrice will contribute to a significant improvement in oral hygiene with less staining compared with using a 0.12% chlorhexidine rinse.