Previous studies have suggested that if either sugar-free or sucrose-containing chewing gum is chewed after acidogenic meals or snacks, the plaque pH response to the latter is reduced and the potential for remineralisation of experimental white spot caries lesions is enhanced. This study has compared the effects of both gums on plaque pH (measured by the sampling technique) in 10 subjects who chewed the gums after standard acidogenic challenges (sucrose rinse, cupcake, and fried chicken dinner). The results showed that while both gums can significantly reduce the acid response, sugar-free gum appears more effective.

Previous plaque-pH telemetry studies Imfeld, (Karger Press 1983) and Maiwald (Zahn-Mund-Kieferheilkd, 70: 1982) reported the acidogenicity of various foods and dietary patterns to estimate potential cariogenicity. To avoid patient discomfort, improve compliance, and avoid electrode shorting problems, we simplified our telemetry method and compared it to our previously published model. A removable partial prosthesis with a glass electrode set in the approximal space in the gap left by a missing first molar was used in 2 subjects. In the modlfied method (MM) subjects suspended oral hygiene for 3 days, the prosthesis was installed on the 3rd day, accumulated plaque was spread on the electrode and covered with gauze to avoid removal. For comparison, the same subjects wore the prosthesis in the mouth (PM) during plaque accumulation. 24 test sessions compared the plaque pH response to 4 treatments: a 10% sucrose rinse (SR), a 10% sorbitol rinse (SO) a snack roll with marmalade and coffee (SN), and SN followed by gum chewing (SN+G). pH curves were similar and selected time intervals (baselines and minimas) showed no differences in mean pH response between the 2 methods. The new method improved participation, reduced the number of “failed” runs and showed Stephan curves comparable to conventional methods.

Previous plaque-pH telemetry studies reported the acidogenicity of various foods and dietary patterns to estimate potential cariogenicity. To avoid patient discomfort, improve compliance, and minimize electrode malfunctions, we have simplified our telemetry method and compared it to our previously published model. A removable partial prosthesis with a glass electrode set in the approximal space left by a missing first molar was used in 2 subjects. In the modified method, subjects suspended oral hygiene for 3 days, the prosthesis was then installed on the 3rd day, and accumulated plaque was spread on the electrode and covered with gauze for retention. In comparative tests, the same subjects wore the prosthesis in the mouth during plaque accumulation. Test sessions compared the plaque pH response to 4 treatments: a 10% sucrose rinse, a 10% sorbitol rinse, a snack roll with marmalade and coffee, and the snack followed by gum chewing. Overall, pH curves were similar (mean baselines and minimas) and no significant differences in mean pH response were noted between the 2 methods.

The modified method improved subject participation, demonstrated greater reliability, and showed Stephan curves comparable to conventional methods.

Saliva stimulation by gum chewing has been reported (Br. Dent. J. 167: 6:204-2085, 1989) to neutralize plaque acidity. To attempt to confirm these findings with different methodoIogy, we compared the plaque pH response to bread with honey followed by sucrose or sorbitol sweetened gum chewing for 20 minutes. Bread and honey was chosen as previous work in our laboratory found this a “worst case” challenge in terms of the extent and duration of the pH decline. The study design was: 4 subjects x 2 repIicates x 3 treatments: food (F), food followed by sorbitol chewing gum (F+SO), and food followed by sucrose chewing gum (F+SU). Subjects accumulated plaque for 3 days, a partial prosthesis with a glass electrode was set in the approximal space in the gap left by a missing first molar, and the accumulated plaque spread on the electrode. pH was monitored for 150 min: Baseline (0-10), food (11-30), + Gum Chewing (31-50), post chew monitoring (51-150).

ANOVA showed: No differences at baseline, (0.01 for either gum vs. no gum during, and post chew, and p(0.06 for sugar vs. ORBIT sugarfree gum post chew. PH data was also converted to cH areas F:1703, F+SO:53, F+SU156. While the post chew pH curves were not identical for sucrose vs. sorbitol chewing gums, both neutralized plaque acidity probably due to a common salivary action.

Saliva stimulation by gum chewing has been reported to neutralize plaque acidity. We compared the plaque pH response to bread with honey followed by sucrose-or sorbitol-sweetened gum chewing for 20 minutes. Bread and honey was chosen as previous work in our laboratory found this a worst case challenge in terms of the extent and duration of the pH decline. The study design was factorial with: 4 subjects x 2 replicates x 3 treatments. Each subject received each of the 3 treatments: food (bread and honey), food followed by sorbitol chewing gum, and food followed by sucrose chewing gum. Subjects accumulated plaque for 3 days on a partial prosthesis with a glass electrode set in the approximal space in the gap left by a missing first molar. Plaque pH was monitored for 150 min: baseline (0-10), food (11-30) + gum chewing (31-50), post-chew monitoring (51.150).

ANOVA of mean plaque pH showed no difference between treatments at baseline. Significantly higher pH levels (p(0.01) were shown with both gums compared to no gum during the chew and post chew phases. Plaque pH data compared to no gum during the chew and post-chew phases. Plaque pH data were also converted to absolute acid values (cH). Food alone produced 1703 (mol/min; food followed by sucrose gum produced 156 (mol/min. While the post-chew pH curves were not identical for sucrose vs. sorbitol chewing gums, both neutralized plaque acidity, probably due to the induced salivary action (J Clin Dent 3:75-78, 1992.)

Recent publications have suggested that chewing sorbitol- or sucrose-containing gum after a snack or meal can reduce development of caries by neutralizing dental plaque acids at interproximal sites in the dentition. To confirm these findings four volunteers wore appliances containing a miniature pH electrode. After plaque accumulation, subjects ingested a bowl of sugar-coated cereal with milk and 20 minutes later chewed a sorbitol-containing gum, a sucrose-containing gum, or did not chew anything for 20 minutes. After exposure to the cereal, the plaque pH fell within 20 minutes from approximately 6.4 to 4.8. Sorbitol gum caused the pH to rise to 5.5, while the sucrose gum caused the pH to rise to only 5.1. After cessation of chewing, the pH in all cases dropped to 4.5 or lower. No statistically significant difference could be shown between plaque pH changes with the various protocols. Gum chewing after eating caused only a transient elevation in plaque pH.

The aim of the study was to compare three methods for pH measurements of human dental plaque, i.e. the telemetric, the microtouch and the sampling method, after consumption of starchy food products. All volunteers (N=10) were equipped with a partial lower telemetry prosthesis incorporating a miniature glass pH-electrode. They refrained from tooth brushing for 3 days. Four products were tested: 1) soft bread, 2) potato chips, 3) 5% starch solution, and 4) 5% sucrose solution. pH of plaque was measured using the three methods simultaneously at various time points after consumption. The results demonstrated that the pH at the 10-min measurements were in mean 1.5 units lower for the telemetric method than for the sampling method and 1.0 units lower than for the microtouch method. The sampling method was hardly able to differentiate starch from sucrose solution or soft bread from potato chips. The microtouch and telemetric methods were able to rank the four test products. The maximum pH decrease was lower and more quickly reached for the two mouth rinse solutions, while the soft bread and potato chips showed a somewhat lower pH recovery. We therefore conclude that there were biq differences in pH level between the three methods and that the two starch food products were easily fermented in dental plaque. This investigation was supported by the Swedish Medical Research Council, - Patentmedelsfonden for Odontologisk Profylaxforskning and the Swedish Dental Association.

Chewing gum for 20 min after meals and snacks promotes remineralization of experimental enamel lesions, whether the gum be sweetened with sucrose or sorbitol [Caries Res 1990;24:405]. Parallel reductions in plaque pH response have been reported using telemetry; this study aims to reinvestigate the potentially beneficial response to chewing gum after acidogenic challenges, using a plaque sampling technique. Plaque pH responses were recorded at intervals over 60 min in 10 volunteers after (A) a sugary snack (cupcake) alone; (B) a snack followed by sugar-free gum (20 min); (C) a snack followed by sugared gum; (D) a 10% sucrose mouth-rinse; (E) a rinse followed by sugar-free gum, and (F) a rinse followed by sugared gum.

Analysis of variance showed significant treatment effects with gum for snack, rinse, minimum pH, .and cH Area. Significant (p (0.05) differences were: minimum pH, A vs. B, A vs. c, D vs. E, D vs. F; cH area, A vs. B, D vs. E. The results tend to confirm that with two levels of prior acidogenic challenge, both sugared and sugar-free gum may reduce plaque pH.

This randomized, double-blind, crossover study in 8 subjects compared the effects of sucrose and sorbitol chewing gums on plaque pH, both alone and following an acidogenic challenge. After 3-6 days of plaque accumulation, subjects chewed one piece of sorbitol or sucrose gum for 10, 15, or 20 minutes alone or following consumption of a cream-filled cookie. Plaque pH was recorded for 2 hours using indwelling pH wire-telemetry (Park et .al. Am J Dent, 3: #5, 1990), and the area of the curve below pH 5.5 and the lowest pH reached were determined. The results indicated that: (1) chewing sucrose gum alone produced a significantly (p<0.05) greater acidogenic response than sorbitol gum (i.e., 4779 vs. 0 area units below pH 5.5 and 4.62 vs. 5.98 minimum pH); (2) sorbitol gum mediated the pH response significantly more than a sucrose gum (i.e., 84 vs. 3792 area units below pH 5.5. and 5.62 vs. 4.82 minimum pH following gum chewing); (3) the longer both gums were chewed, the greater the reduction in area under 5.5 and the higher the pH minimum.

This study demonstrates that sorbitol and sucrose gums do not affect plaque DH responses comparably.

The aim was to study the effects of different pasta products on pH of human interdental plaque in vivo and to compare these to in Sweden traditionally used starch-containing food products. The degree of hydrolysis in saliva was also studied.

In total 10 subjects participated, who refrained from toothbrushing for 3 days, pH of plaque was studied, using the so called touch method before and at various points after consumption. Ten products were tested: 1) Spagetti, 2) macaroni, 3) spaghetti with high content of fibre, 4) pasta porridge, 5) potato, 6) rice, 7) bread, 8) sweetened bread, 9) glucose tablet and 10) 10% sucrose solution. Saliva samples were collected at three occasions after the intake for analysis of low molecular weight carbohydrates (maltose and maltotriose).

The sucrose solution resulted in the greatest pH drop followed, in order, by the glucose tablet, sweetened bread, bread and potato. All pasta products induced smaller pH falls and gave, together with rice, similar results. Comparing the degree of hydrolysis in saliva, significant differences were obtained between bread and spaghetti at 6 min after the intake. Only small differences were found at the other time points.

In conclusion, all starch-containing food products were easily fermented in dental plaque, but the pasta and the rice to a lesser extent than the bread and potato.

The objective of this study was to evaluate the effect of chewing sorbitol gum on plaque pH following the ingestion of acidogenic fast-food meals. Plaque pH response was monitored using an indwelling wire-telemetry system in five adult panelists. From a pilot study with 12 fast-food meals, the most acidogenic breakfast, lunch and dinner were selected for this study. In the first test, the fasted, resting plaque pH was recorded for 5 minutes; panelists ingested the selected meals for 10 minutes, rinsed thoroughly with 50 ml of tap water, and the pH response was monitored for the remainder of a 2-hour period. In the second test series, the same procedures were followed through the post-meal ingestion rinse. After the pH response to the meal was monitored for 5 minutes, the panelists chewed a sorbitol gum for 15 minutes in their usual manner and the panelists were encouraged to move the gum around their mouth, however, it appeared as if they favored the side of their mouth without the partial denture. The pH response was monitored for the balance of the 2-hour period. All panelists ate the test foods, with and without the chewing gum, according to a randomized-block test design. The results indicated that the use of sorbitol gum significantly raised the plaque pH, prevented the subsequent pH drops after the fast-food meal ingestion and reduced the pH curve area under 5.5.

The purpose of this study was to determine the effect of chewing a sorbitol gum (Trident) for 10 minutes on interproximal plaque pH changes following ingestion of selected sucrose- or starch-containing foods. The snacks containing predominantly sucrose (and/or simple sugars) were chocolate bar, cream-filled cupcakes, cream-filled sandwich cookie, cherry pie and raisins. The snacks containing predominantly starch were oat cereal, granola bars, pretzels, potato chips and corn chips. Plaque pH responses were monitored using an indwelling wire-telemetry system in five adult panelists. The test design involved two sets of 5 x 5 Latin square randomization in which each set consisted of two series of tests. In the first series of tests, the fasted, resting plaque pH was recorded for 5 minutes, panelists ingested the designated snacks for 2 minutes, and the pH response was monitored for the remainder of a 2-hour period. In the second series of tests, the same procedure was followed through the snack ingestion. After the pH response to the snack was monitored for 15 minutes, the panelists were asked to chew one stick of sorbitol gum for 10 minutes and the pH response was then monitored for the balance of the 2-hour period. Results indicated that both the sugar- and starch-containing snacks tested in this study caused significant decreases in interproximal plaque pH. Chewing a sorbitol gum after ingestion of the snacks significantly reduced the demineralizing potential of the plaque. The chewing of sorbitol gum following the ingestion of snacks can be recommended as an adjunct to other caries-preventive oral hygiene measures.

The purpose of this work was to study the effect of chewing a sorbitol-sweetened gum on whole and parotid salivary flow rates, and on the cemental plaque pH response to a sucrose rinse challenge, in subjects with low salivary flow. The results show that chewing a flavoured sugarless gum significantly increases salivary flow rates in individuals with dry mouth. Additionally, chewing the sorbitol-sweetened gum effectively prevents the fall in cemental plaque pH generally seen in response to a sucrose challenge. This indicates that chewing a sorbitol-sweetened gum provides a palliative and possibly a protective benefit for people who suffer from dry mouth.

Significant advances have been made in the research to establish a reliable means to evaluate the cariogenic potential of foods. Reasonable test systems are being developed, and through collaborative studies it is likely that a scheme for testing foods will be developed. How such a scheme will be used to produce benefits for oral health should and will be the focus of considerable debate. Various issues need to be addressed. The most reasonable immediate goal in this area would be the global acceptance of the interproximal plaque pH test as a means to produce non-acidogenic products.

After recent modifications in the composition of cariogenic chewing gum, a gum that is non-cariogenic and may even have caries-prevention action has been developed by industry. The authors of this chapter express the hope that it can be taken as an example of what could be done with other cariogenic confections or baked goods by industry. The chapter reviews the history of chewing gums, with discussion of chewing gums containing the following: phosphate reagents; acid-neutralising agents, enzyme blocking agents ( vitamin K, chlorophyll, furadoxyl), fluoride, Different non-cariogenic sweetners are discussed: saccharine; sugar alcohols. The possibility of using chewing gum to prevent or treat diseases of the gums is briefly discussed.

The objective of this study was to evaluate the effect of chewing sorbitol gum on plaque pH following the ingestion of acidogenic fast-food meals. Plaque pH response was monitored using an indwelling wire-telemetry system in five adult panelists. From a pilot study with 12 fast-food meals, the most acidogenic breakfast, lunch and dinner were selected for this study. In the first test, the fasted, resting plaque pH was recorded for 5 minutes; panelists ingested the selected meals for 10 minutes, rinsed thoroughly with 50 ml of tap water, and the pH response was monitored for the remainder of a 2-hour period. In the second test series, the same procedures were followed through the post-meal ingestion rinse. After the pH response to the meal was monitored for 5 minutes, the panelists chewed a sorbitol gum for 15 minutes in their usual manner and the panelists were encouraged to move the gum around their mouth, however, it appeared as if they favoured the side of their mouth without the partial denture. The pH response was monitored for the balance of the 2-hour period. All panelists ate the test foods, with and without the chewing gum, according to a randomized-block test design. The results indicated that the use of sorbitol gum significantly raised the plaque pH, prevented the subsequent pH drops after the fast-food meal ingestion and reduced the pH curve area under 5.5.

Interproximal plaque pH responses to five different meals were investigated in this study. All meals were found to be acidogenic, with pH challenges lasting well over one hour. The effects of chewing one sorbitol and two different types of sucrose-containing gum for 20 minutes after the meal were examined. All three types of gum reversed the acid challenge of the meal and resulted in an interproximal pH level that is considered ‘safe for teeth’. This study indicates that meals can be very acidogenic and that, in addition to normal preventive dental procedures, chewing gum for 20 minutes after meal consumption should be considered, to reduce the cariogenic challenge to the teeth.

Indwelling interproximal plaque pH telemetry was used to compare pH responses to five normal meals and one lowly-acidogenic meal with and without a sweet at the end of the meal. Four volunteers with a mean age of 27 years were fitted with wire-telemetric appliances containing glass pH microelectrodes on mandibular first permanent molars. Fasting plaque, age 4-7 days, was used for all tests. Test sessions consisted of meal consumption during a 20-minute period followed by a 600 minute test period. ANOVA* and Duncan’s multiple range test was used to analyze pH responses (area, cH minimum) for all meals with and without desserts. Statistically significant differences existed for all measurements at p< .001. Duncan’s multiple range test however, indicated that the only different group was the low carbohydrate meal without dessert - ham, diet soda and lettuce salad which produced a minimum’ pH of 5.2 = 1.2. All other responses, were not significantly different.

Results of this study indicate that five different normal meals with and without dessert and a low carbohydrate meal with dessert all produce significant interproximal plaque pH responses. Prolonged acid challenges do not differ if dessert is included unless the meal is extremely low in carbohydrate.

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.

The purpose of this study was to determine the effect of chewing a sorbitol gum (Trident) for 10 minutes on interproximal plaque pH changes following ingestion of selected sucrose- or starch-containing foods. The snacks containing predominantly sucrose (and/or simple sugars) were chocolate bar, cream-filled cupcakes, cream-filled sandwich cookie, cherry pie and raisins. The snacks containing predominantly starch were oat cereal, granola bars, pretzels, potato chips and corn chips. Plaque pH responses were monitored using an indwelling wire-telemetry system in five adult panelists. The test design involved two sets of 5 x 5 Latin square randomization in which each set consisted of two series of tests. In the first series of tests, the fasted, resting plaque pH was recorded for 5 minutes, panelists ingested the designated snacks for 2 minutes, and the pH response was monitored for the remainder of a 2-hour period. In the second series of tests, the same procedure was followed through the snack ingestion. After the pH response to the snack was monitored for 15 minutes, the panelists were asked to chew one stick of sorbitol gum for 10 minutes and the pH response was then monitored for the balance of the 2-hour period. Results indicated that both the sugar- and starch-containing snacks tested in this study caused significant decreases in interproximal plaque pH. Chewing a sorbitol gum after ingestion of the snacks significantly reduced the demineralizing potential of the plaque. The chewing of sorbitol gum following the ingestion of snacks can be recommended as an adjunct to other caries-preventive oral hygiene measures.

Paraffin -or unflavoured chewing gum is routinely administered after carbohydrate challenges to stimulate salivary’ flow which increases clearance and neutralizes plaque acids during in viva pH testing. This study compares an unflavoured gum base (GB) to a peppermint flavored sorbitol chewing gum (Extra) for their effects on stimulating saliva flow and interrupting the increased acidity (pH) and ionized plaque calcium (pCa) induced by a glucose challenge. Six subjects wore maxillary Hawley appliances with pH, and pCa sensors for the study. Swallowing was recorded by pressure sensor or patient signals (AADR Abs 998, 1986). Ten minutes after a sugar rinse, subjects chewed Extra or GB for five minutes. All parameters were then monitored for 10 minutes. During chewing, Extra returned plaque pH to higher mean value than GB (p ( .001l). Post chew Extra elevated plaque pH to above baseline (7.4 vs 6.9 GB) and maintained a pH, which was significantly higher (p <..001) throughout monitoring. GB did not return to baseline pH following chewing, and there were no differences in the number of swallows, or pCa levels between the two groups.

A flavoured sweetened chewinq gum (Extra) increased saliva stimulation and neutralized plaque acid levels compared to baseline and an unflavoured gumbase.

The effects of chewing a flavoured or unflavoured gum after a carbohydrate challenge were studied using saliva stimulation, plaque pH and ionized calcium as monitoring parameters. A commercially available sorbitol chewing gum (CG) stimulated a significant greater number of swallows (p(0.05, n=6) than an unflavoured gum base (GB) during five minutes chewing protocol. After chewing was stopped, no differences were observed. Plaque pH measurements were made using multiple iridium oxide electrodes positioned in interproximal posterior sites of the maxillary arch. Results showed that chewing either GB or CG for five minutes after a 5% glucose rinse reversed the acid challenge to plaque. CG was significantly more effective (p(0.001) in its ability to maintain plaque pH during the ten minutes after chewing was stopped. No significant differences in ionized calcium levels were observed at interproximal sites during and after chewing CG or GB. Results suggest that saliva stimulated by chewing limits the duration of acidogenic challenge to maxillary interproximal sites. A flavoured/sweetened masticatory stimulant was more effective in stimulating saliva flow and reversing acidogenic effects of a glucose rinse than an unflavoured stimulant.

Purpose of this study was to evaluate the acidogenic potential of five different well-balanced meals and assess the effect of chewing gum after a meal. Five representative meals were provided to 3 volunteers for measurement of acidogenic potential using indwelling wire-telemetric appliances containing glass pH microelectrodes. One selected meal was provided to 5 volunteers for comparing the acid challenge with and without the use of sorbitol (Extra®) and sucrose (Doublemint®) chewing gums for 20 minutes at the end of the meal. Plaque pH responses were continuously recorded for 120 minutes after a 20 minute meal in each recording session. All five meals resulted in plaque responses below pH 4.5 and did not recover to resting values in the next 120 minute period. The grand mean for minimum pH for the 5 meals was 4.21 + 0.16. ANOVA for subjects and meals by minimum pH and pH below pH 5.7 showed no statistically significant differences. Comparison of one meal with and without gum chewing after the meal resulted in complete reversal of the acid challenge to the resting pH. These pH values did not drop below pH 5.7 during the remainder of the recording session (100 minutes). The t-test for pH below pH 5.7 with and without gum chewing was significantly different (p<.001). The results indicate that all five well-balanced meals produced prolonged acid challenges to the dentition. Using one representative meal, the acid challenge can be rapidly reversed and maintained near the resting pH by chewing sorbitol or sucrose gum for 20 minutes following the meal. This study was supported by the Ctr. for Clin. Stud., NIH/NIDR, grant BP50 DE07010 and the Wm. Wrigley Jr. Company.

The primary aim of this study was to rank several foods (apple drink, caramel, chocolate, cookie, skimmed milk powder, snack cracker, and wheat flake) according to their plaque pH response as monitored in a panel of 12 volunteers by the plaque sampling method for comparison with data previously reported with other methods used to access cariogenisity potential. Secondary experiments (using subsets of the panel of subjects) were undertaken in an attempt to elucidate some of the reasons for the observed plaque pH changes. Oral carbohydrate retention was measured at a single time period after food use as total anthrone-positive carbohydrate material, and as specific acidogenic sugars by gas-liquid chromatography after gel-exclusion chromatography. The concentrations of acid anions in the plaque fluid after food consumption were measured by isotachophoresis eight min after food use. According to the plaque pH response, apple-flavored fruit drink and chocolate were the most acidogenic foods and skimmed milk powder the least acidogenic. There were significant correlations (p ( 0.05) between plaque pH data and lactate-plus-acetate concentrations in plaque fluid, but the correlations between the pH data and any of the carbohydrate retention parameters were not significant.

The ‘purpose of these studies was to determine the effect of changing the time interval between food ingestion and chewing a sugarless gum as well as the duration of gum chewing on plaque acidogencity.

The indwelling pH electrode model idenified by the ADA Foods, Nutrition and Dental Health programme was used. In the first study, the panelists were used in all items (pretzel, potato chips, corn chips and granola bar) in a latin square design. Plaque pH curves of 3-7-day-old plaque were recorded for two hours. The panelists than repeated the test design at a later date except they chewed a sorbitol-containing gum for a 10-minute period 15 minutes following food ingestion. The second study was identical except the gurn chewing period was 15 minutes (rather than 10) after a 5-minute (rather than 15) post ingestion period. Parameters monitored included area of the pH curve below 5.5, lowest pH attained, maximum pH drop and time below pH 5.5. The data indicate that when the gum was chewed for a longer time period and chewing was started 10 minutes sooner after the food-ingestion, the area, under pH S.S was reduced by a significantly larger percentage (89 vs 65%). minimum pH attained was significantly higher (1.32 vs 0.38 pH units) and maximum pH drop was significantly reduced (1.18 vs 0.36 pH units). Time under pH 5.5 was numerically but not significantly reduced by reducing the time interval between ingestion of food and the chewing of the sorbitol-containing gum. The results indicate that when the gum was chewed closer to food ingestion and for a longer time period, significantly reduced cariogenic challenge from each of the foods were observed over the two-hour monitoring periods.

Adequate salivary flow is important for patient comfort and maintenance of oral health. Xerostomia, or dry mouth, is a common clinical complaint. Masticatory and gustatory activity can stimulate salivary flow from functional salivary tissue and the use of sugarless mints and gums have been recommended to individuals who complain of xerostomia, but there are minimum clinical data. A clinicial study assessing the effect of salivary flow rates and dental plaque pH of a sorbitol-sweetened chewing gum in subjects with the complaint of xerostomia. Statistically significant stimulated whole mouth and parotid salivary flow rate increases were found when compared to unstimulated whole mouth and parotid salivary flow rates. Chewing of the sorbitol sweetened gum also effectively reduced the drop in pH seen following the exposure to a fermentable carbohydrate. The findings of this present study indicate that chewing of a sorbitol-sweetened gum may be of benefit to patients with the complaint of xerostomia.

Interproximal wire-telemetric appliances were used in this study to obtain interproximal plaque pH data from the distal surface and salivary pH data from the buccal surface of lower mandibular molars. Five different test foods - a granola bar, a fruit bar, a Danish pastry, an apple and a jelly sandwich - were used as test food substances. The pH changes from these test foods were recorded continuously for 120-minute periods in each of five human volunteers. Subsequently, two separate series of test sessions were conducted using peppermint flavored sugarless gum or a grape flavored sugarless gum to observe the effects of chewing these gums for a ten-minute period on both the salivary and interproximal plaque pH. Dramatic pH drops were observed with test foods in interproximal with a varying rate of return toward the resting values. Minimum plaque pH values were similar for all test foods. Salivary pH values, however, differed markedly. Minimum pH values achieved for the salivary responses were not statistically different from the minimum plaque pH values for the fruit bar and apple. The other three test foods showed a higher minimum salivary pH level, which was statistically significant. Both peppermint and grape flavored chewing gums, chewed for a ten-minute period after ingestion of the challenge food, resolyed in a relatively rapid pH return, for both saliva and plaque, to the resting values. Salivary and plaque pH remained above a mean pH level of 6.4 during a 30-minute post chew recording period.

Saliva is known to be involved in plaque pH regulation: however, the degree of effect from stimulated saliva is not fully understood. This paper reports saliva flow rates during the use of chewing gum sweetened with sorbitol (CGsorb) or sucrose (CG Sucr) versus rates with breath mints (Msorb or Msucr). Correspondingly, interproximal plaque pH changes were followed during use of each stimulus alone and 15 min. after ingestion of a sucrose snack.

Parotid glands were cannulated in 4 subjects at about 2 h after meals. Duplicate runs were made for each stimulus, and secreted volumes were recorded at 1-min. intervals for 20 min. Flow rates varied by subject and by the physical form of the stimuli. CG The mean flow rates for CGsorb (0.30 ml/min) and CGsucr (0.33 ml/min) were not different, but were greater than flow rates with either breath mint. The corresponding rates for Msorb (0.13 ml/min) and Msucr (0.18 ml/min) were different from each other and higher and resting rates.

Five subjects were fitted with interproximal indwelling pH electrodes. After eating a sucrose snack, and waiting 15 min, the pH drop to - 4.00 was reversed to pH 5.5 within 8 min. with CGsorb and within 11 min. with CGsucr. The corresponding pH rises were 40 min. for Msorb and >60 min for Msucr Gum chewing further neutralized plaque acids to pH 7.0 within 14-18 min, while breath mints were ineffective.

The primary factor contributing to the acid-neutralizing benefit of chewing gum is its ability to deliver the natural protective qualities of saliva interproximally through mastication and the sweet stimuli.

Plaque acidity studies form a rational basis for providing partial evidence of Cariogenic potential incorporating features not reproduced by other tests (e.g. patterns of food use). Plaque pH data represent the summation of the effects of many microbial and physiological factors of relevance to cariogenic potential. Different plaque pH models may satisfy alternative test requirements, depending upon their performance characteristics, but parallelism exists among models, and between plaque pH test results and findings from other cariogenicity testing methods.

Criteria for selection of subjects and methodology are reviewed, and the validity of the use of pH in statistical procedures discussed. The analysis of organic acid concentration in plaque is relevant to cariogenicity, but the full significance of the acid spectrum is not fully elucidated. The relationship between pH and carious demineralization is no-linear, and plaque pH data should be used to compare foods in relation in internal standards. Finally, the effects of eating frequency, food sequences, and mixtures may modify the response to an individual food item and should be taken into account when one interprets the results of such tests.

The effects of chewing sorbitol-containing gum and paraffin upon human interproximal plaque pH responses after consumption of a jelly doughnut were investigated in this study. Prolonged plaque pH responses were observed following consumption of the jelly doughnut. Dramatic rises in pH resulted when sorbitol gum and paraffin were chewed 15 min after consumption of the doughnut. Ten minutes of chewing resulted in significantly higher (p ( 0.01) pH values than 5 min of chewing.

Interproximal wire-telemetric plaque pH data were obtained from five volunteers after they ate milk chocolate bars, raisins, chocolate wafer cookies with cream filling, cupcakes with icing and cream filling, and cherry pies. All the foods produced rapid decreases in plaque pH for extended periods. In a second set of test sessions, volunteers chewed sugarless gum for 10 minutes, starting 15 minutes after they ate the snack food. In all cases, the gum chewing caused a rapid increase in plaque pH. The pH remained at a level considered safe for teeth for 30 minutes after chewing the gum.

It is generally accepted that the carious process is initiated and maintained by the presence of sugar and bacteria which decompose this sugar. The term ‘sugar’ means not only household sugar, i.e. the disaccharide sucrose, but all low-molecular carbohydrates. They are converted to acids by the microbial metabolism. Streptococcus mutans plays the greatest role in this. Food technologists and educators are challenged to reduce the sugar consumption particularly of children but also of adults to a reasonable level.

Significant advances have been made in the research to establish a reliable means to evaluate the cariogenic potential of foods. Reasonable test systems are being developed, and through collaborative studies it is likely that a scheme for testing foods will be developed. How such a scheme will be used to produce benefits for oral health should and will be the focus of considerable debate. Various issues need to be addressed. The most reasonable immediate goal in this area would be the global acceptance of the interproximal plaque pH test as a means to produce non-acidogenic products.

Main section summary 101-116: The fall in pH of interdental plaque after consumption of certain important dietary carbohydrates shows their highly acidogenic character. A summary of numerous investigations of the relationship of foods and caries reveals that in all reports it is the frequent consumption of sweets and snacks, mostly between meals, that coincides with a higher caries in the subjects. Snack foods certainly have a strong cariogenic potential because they combine the detrimental effects of high sugar content and high frequency of consumption. Representative examples of plaque pH telemetric evaluations of commonly sold confectionery products are presented in the chapter. A considerable reduction of the total sugar consumption would be desirable. A reduction of fermentable sugars contained in between-meal snacks and confectionery products seems a more feasible target to strive for.

By measuring the in vitro pH of plaque taken from humans and by applying the method of in vivo plaque pH telemetry, the plaque pH curve was plotted after sorbitol, xylitol and sucrose flavored gums had been chewed. The sucrose flavoured chewing gum has a sight pH reducing effect, whereas sorbitol and xylitol flavoured chewing gum did not. Furthermore, chewing gum not flavoured with sucrose is appropriate for neutralizing the low pH produced by sugar-containing foods. Thus, we can offer infer that chewing gum not flavoured by sucrose has a preventive effect.

The relative cariogenic potential of starch and starchy foods is an issue of importance and controversy. There is little question that starch can be degraded in the oral cavity to substances that can be fermented to acid by plaque bacteria. Starch has been shown to have significant cariogenic potential in the rat-model. The cariogenic potential of starch could be influenced by a large number of factors ranging from the processes used in food manufacturing to the interactions that are involved in salivary amylase production and function. The issue is complex, as starchy foods are usually never eaten in the absence of more rapidly fermentable carbohydrates. Also, the effect on caries of a mixture of highly and moderately metabolisable compounds is totally unknown.

A survey of the relationship between caries prevalence and the consumption of sugar and other foods by man has been interpreted to show that snack foods share importance with sucrose in caries causation. Support for this conclusion is found in animal experiments and some in vitro and in vivo tests.

Both glass and antimony electrodes were used to measure the effect of gum chewing and tooth brushing on the pH of dental plaques following 25 per cent glucose rinses. Two groups of six subjects substained from regular oral hygiene procedures from 3 days prior to tests to the end of each series of experiments. Two interproximal and one smooth-surface pH readings were taken in both maxillary quadrants. Chewing (10 minutes) and brushing (30 seconds) were restricted to the right quadrant. Readings were taken in most cases at 10 minute intervals. Brushing with and without water and by three brushing techniques were investigated. While pH values showed considerable variation by surface between subjects and within the same individual on different days, the following conclusions are supported by marked statistical significance. Brushing per se, with or without water, had little effect on plaque pH, In most subjects the chewing of gum* gave a marked, rapid, and sustained rise in pH. *Dentyne chewing gum