The effect of adding calcium lactate to xylitol chewing gum on remineralization of enamel lesions

The purpose of the study was to determine whether adding calcium lactate to chewing gum containing xylitol enhances remineralization of enamel surfaces using an early caries lesion model. Enamel slabs were cut from human extracted sound teeth and artificial subsurface lesions created within each. Half the enamel slabs were used as controls and stored in a humidifier while half were mounted into oral appliances worn by 10 volunteers (22-27 years old, 2 males and 8 females) in a three-leg trial, during which they wore the appliance without chewing gum, chewed gum containing xylitol + calcium lactate or chewed gum containing only xylitol 4 times a day for 2 weeks. Calcium concentrations in the enamel surfaces of control and test slabs were measured by X-ray spectrometry and degrees of remineralization were calculated. The mean degree of remineralization was greater after chewing xylitol-Ca gum (0.46 +/- 0.10) than after no gum (0.16 +/- 0.14) or after chewing xylitol gum (0.33 +/- 0.10) (p < 0.01). In conclusion, chewing gum containing xylitol + calcium lactate could enhance remineralization of enamel surface compared to chewing gum containing only xylitol or no gum chewing.     

Acid resistance of enamel subsurface lesions remineralized by a sugar-free chewing gum containing casein phosphopeptide-amorphous calcium phosphate

The aim of this clinical study was to investigate the acid resistance of enamel lesions remineralized in situ by a sugar-free chewing gum containing casein phosphopeptide-amorphous calcium phosphate nanocomplexes (CPP-ACP: Recaldent). The study utilized a double-blind, randomized, crossover design with two treatments: (i) sugar-free gum containing 18.8 mg of CPP-ACP, and (ii) sugar-free gum not containing CPP-ACP as control. Subjects wore removable palatal appliances with insets of human enamel containing demineralized subsurface lesions and chewed the gum for 20 min 4 times per day for 14 days. After each treatment the enamel slabs were removed and half of each lesion challenged with acid in vitro for 8 or 16 h. The level of remineralization was determined using microradiography. The gum containing CPP-ACP produced approximately twice the level of remineralization as the control sugar-free gum. The 8- and 16-hour acid challenge of the lesions remineralized with the control gum resulted in 65.4 and 88.0% reductions, respectively, of deposited mineral, while for the CPP-ACP-remineralized lesions the corresponding reductions were 30.5 and 41.8%. The acid challenge after in situ remineralization for both control and CPP-ACP-treated lesions resulted in demineralization underneath the remineralized zone, indicating that the remineralized mineral was more resistant to subsequent acid challenge. The results show that sugar-free gum containing CPP-ACP is superior to an equivalent gum not containing CPP-ACP in remineralization of enamel subsurface lesions in situ with mineral that is more resistant to subsequent acid challenge.     

Effect of addition of citric acid and casein phosphopeptide-amorphous calcium phosphate to a sugar-free chewing gum on enamel remineralization in situ

Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) has been shown to remineralize enamel subsurface lesions in situ. The aim of this study was to investigate the effects of CPP-ACP in a fruit-flavoured sugar-free chewing gum containing citric acid on enamel remineralization, and acid resistance of the remineralized enamel, using an in situ remineralization model. The study utilized a double-blind, randomized, crossover design with three treatments: (i) sugar-free gum (2 pellets) containing 20 mg citric acid and 18.8 mg CPP-ACP, (ii) sugar-free gum containing 20 mg citric acid alone, (iii) sugar-free gum not containing CPP-ACP or citric acid. Ten subjects were instructed to wear removable palatal appliances, with 4 half-slab insets of human enamel containing demineralized subsurface lesions and to chew gum (2 pellets) for 20 min 4 times per day for 14 days. At the completion of each treatment the enamel half-slabs were removed and half of the remineralized lesion treated with demineralization buffer for 16 h in vitro. The enamel slabs (remineralized, acid-challenged and control) were then embedded, sectioned and subjected to microradiography to determine the level of remineralization. Chewing with gum containing citric acid and CPP-ACP resulted in significantly higher remineralization (13.0 +/- 2.2%) than chewing with either gum containing no CPP-ACP or citric acid (9.4 +/- 1.2%) or gum containing citric acid alone (2.6 +/- 1.3%). The acid challenge of the remineralized lesions showed that the level of mineral after acid challenge was significantly greater for the lesions exposed to the gum containing CPP-ACP.     

Remineralization of enamel subsurface lesions by sugar-free chewing gum containing casein phosphopeptide-amorphous calcium phosphate.

Casein phosphopeptide-amorphous calcium phosphate nanocomplexes (CPP-ACP) exhibit anticariogenic potential in laboratory, animal, and human in situ experiments. The aim of this study was to determine the ability of CPP-ACP in sugar-free chewing gum to remineralize enamel subsurface lesions in a human in situ model. Thirty subjects in randomized, cross-over, double-blind studies wore removable palatal appliances with six human-enamel half-slabs inset containing sub-surface demineralized lesions. The appliances were inserted immediately before gum-chewing for 20 min and then retained for another 20 min. This was performed four times per day for 14 days. At the completion of each treatment, the enamel half-slabs were paired with their respective demineralized control half-slabs, embedded, sectioned, and subjected to microradiography and densitometric image analysis, for measurement of the level of remineralization. The addition of CPP-ACP to either sorbitol- or xylitol-based gum resulted in a dose-related increase in enamel remineralization, with 0.19, 10.0, 18.8, and 56.4 mg of CPP-ACP producing an increase in enamel remineralization of 9, 63, 102, and 152%, respectively, relative to the control gum, independent of gum weight or type.     

Effects of various forms of calcium added to chewing gum on initial enamel carious lesions in situ

The purpose of this randomized, cross-over in situ study was to determine the effects of 4 chewing gums on artificial caries-like subsurface lesions. Two chewing gums (1 with zinc citrate and 1 without) contained dicalcium phosphate (3.9%), calcium gluconate (1.8%) and calcium lactate (0.45%), 1 chewing gum contained casein phosphopeptide-amorphous calcium phosphate nanocomplexes (0.7%), and another one contained no calcium. Fifteen subjects without current caries activity (7 male, 8 female; mean age: 27.5 +/- 2.5 years) wore removable buccal appliances in the lower jaw with 4 bovine enamel slabs with subsurface lesions. The appliances were inserted immediately before gum chewing for 20 min and then retained for an additional 20 min. This was performed 4 times per day. Every subject chewed 4 different chewing gums over 4 periods of 14 days each. During a fifth period (control) the subjects only wore the appliances without chewing gum. At completion of each period the enamel slabs were embedded, sectioned and subjected to transversal microradiography. With regard to change of mineral loss and of lesion depth no significant differences could be found between chewing gums containing calcium and calcium-free chewing gums. Moreover, the chewing gum groups and the control group did not differ significantly if adjustments were made for baseline values (p > 0.05; ANCOVA). Under the conditions of the present study it may be concluded that the use of chewing gum offers no additional remineralizing benefit to buccal tooth surfaces, even if the chewing gum contains calcium compounds.     

Effects of a chewing gum containing phosphoryl oligosaccharides of calcium (POs-Ca) and fluoride on remineralization and crystallization of enamel subsurface lesions in situ

Objectives

Manufacturers are adding fluoride (F) to calcium-containing chewing gums to further promote enamel remineralization. The aim of this study was to assess the effect of a chewing gum containing phosphoryl oligosaccharides of calcium (POs-Ca) and fluoride on remineralization of enamel subsurface lesions, in a double-blind, randomized controlled in situ trial.

Methods

Thirty-six volunteer subjects wore removable buccal appliances with three different insets of bovine enamel with subsurface demineralized lesions. For 14 days the subjects chewed one of the three chewing gums (placebo, POs-Ca, POs-Ca + F), three times a day. After each treatment period, the insets were removed from the appliance, embedded, sectioned, polished and then subjected to laboratory tests; mineral level was determined by transverse microradiography (TMR; n = 36), and hydroxyapatite (HAp) crystallites were assessed by synchrotron radiation wide-angle X-ray diffraction (WAXRD; n = 13). Data were analysed by t-test or Wilcoxon rank-sum test with Bonferroni corrections at 0.05 significance level.

Results

Chewing POs-Ca and POs-Ca + F gums resulted in 21.9 ± 10.6 and 26.3 ± 9.4 (mean ± SD) percentage mineral recovery, which was significantly higher than that of placebo gum (15.0 ± 11.4) (p < 0.05). Chewing POs-Ca + F gum resulted in 24.9 ± 5.4 (mean ± SD) percentage HAp crystallites recovery, which was significantly higher compared to POs-Ca (16.0 ± 4.1%) or placebo (11.1 ± 4.8%) gums (p < 0.05).

Conclusions

Addition of POs-Ca to the chewing gum resulted in significant remineralization of enamel subsurface lesions. Although POs-Ca + F gum was not superior in TMR recovery rate when compared with POs-Ca gum, WAXRD results highlighted the importance of fluoride ion bioavailability in the formation of HAp crystallites in enamel subsurface lesions in situ (NCT01377493).     

Remineralization of enamel subsurface lesions by chewing gum with added calcium

Objectives

Chewing sugar-free gum has been shown to promote enamel remineralization. Manufacturers are now adding calcium to the gum in an approach to further promote enamel remineralization. The aim of this study was to compare the remineralization efficacy of four sugar-free chewing gums, two containing added calcium, utilizing a double-blind, randomized, crossover in situ model.

Methods

The sugar-free gums were: Trident Xtra Care, Orbit Professional, Orbit and Extra. Ten subjects wore removable palatal appliances with four human-enamel half-slab insets containing subsurface demineralized lesions. For four times a day for 14 consecutive days subjects chewed one of the chewing gums for 20 min. After each treatment the enamel slabs were removed, paired with their respective demineralized control slabs, embedded, sectioned and mineral level determined by microradiography. After 1-week rest the subjects chewed another of the four gums and this was repeated until each subject had used the four gum products.

Results

Chewing with Trident Xtra Care resulted in significantly higher remineralization (20.67 ± 1.05%) than chewing with Orbit Professional (12.43 ± 0.64%), Orbit (9.27 ± 0.59%) or Extra (9.32 ± 0.35%). The form of added calcium in Trident Xtra Care was CPP–ACP and that in Orbit Professional calcium carbonate with added citric acid/citrate for increased calcium solubility.

Conclusions

Although saliva analysis confirmed release of the citrate and calcium from the Orbit Professional gum the released calcium did not result in increased enamel remineralization over the normal sugar-free gums. These results highlight the importance of calcium ion bioavailability in the remineralization of enamel subsurface lesions in situ.     

Effect of casein phosphopeptide - amorphous calcium phosphate containing chewing gum on salivary concentration of calcium and phosphorus: An in-vivo study

Aim: Caries clinical trials of sugar-free chewing gum have shown that the gum is noncariogenic and in fact has anticariogenic effect through the stimulation of saliva. Sugar-free gums, therefore, may be an excellent delivery vehicle for safe and effective additive, capable of promoting enamel remineralization. Casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) nanocomplexes incorporated into sugar-free chewing gum have shown to remineralize enamel subsurface lesions in situ. So this study was conducted to evaluate the effect of CPP-ACP containing sugar-free chewing gum on salivary concentration of calcium and phosphorous. Materials and Methods : Unstimulated saliva from each 24 selected subjects was collected. Then each subject was given two pellets of chewing gum containing CPP-ACP and asked to chew for a period of 20 min, after which saliva samples were collected from each individual. Once all the samples were collected they were assessed for calcium and phosphorous concentration using affiliated reagent kits and photometer. Statistical Analysis Used: Data obtained were analyzed using student's paired t test. Results: Significant difference was found in the calcium and phosphorus concentration of saliva before and after chewing CPP-ACP containing chewing gum. Conclusions: Chewing of CPP-ACP containing chewing gum showed a significant increase in the salivary concentration of calcium for a prolonged period of time hence it may help in the remineralization of tooth surfaces.     

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.     

Remineralization and acid resistance of enamel lesions after chewing gum containing fluoride extracted from green tea

Background: The aim of this study was to evaluate enamel remineralization and the acquisition of acid resistance by using sugar‐free chewing gum containing fluoride extracted from green tea. Methods: Forty‐five volunteers participated in a crossover, double‐blind study and wore intraoral appliances with human demineralized enamel. Subjects chewed fluoride chewing gum (FCG: 50 μg fluoride) or placebo gum. Remineralization and acid resistance were evaluated using the mineral change value (ΔZ, in vol%·μm). Fluoride concentrations in saliva and remineralized enamel were analysed. Results: The peak salivary fluoride concentration was 3.93 ± 1.28 ppm (mean ± SD). The elevated salivary fluoride concentration resulted in a higher fluoride concentration of 656 ± 95 ppm in the remineralized region versus 159 ± 26 ppm for placebo gum (p < 0.001). After remineralization, the ΔZ of the FCG group was higher than that of the placebo gum group. After an acid challenge, ΔZ of the FCG group was lower than the placebo gum group. Both ΔZ were statistically significant. Conclusions: FCG produced a superior level of remineralization and acid resistance, as compared to the placebo gum. The in situ results suggest that regular use of FCG is useful for preventing dental caries.     

Remineralization of enamel subsurface lesions in situ by the use of three commercially available sugar-free gums

Background.  Commercially available sugar-free chewing gums have been claimed to provide oral health benefits.
Aim.  The aim of this randomized, double-blind crossover in situ study was to compare the efficacy of three commercially available sugar-free chewing gums: Trident White, Orbit, and Orbit Professional, in remineralizing enamel subsurface lesions in situ .
Design.  Specimens containing enamel subsurface lesions were sectioned into test and control half-slabs with the test half-slabs inserted into removable palatal appliances. For each test chewing period, subjects were randomly allocated one of three test gums. Subjects ( n  = 10) chewed the randomly allocated gum for a 20-min period four times per day for 14 days. Each subject chewed all three test gums, with a 7-day washout period between crossovers. After each 14-day cycle, test and control half-slabs were paired, embedded in resin, sectioned, and subjected to microradiography to determine remineralization.
Results.  The gum TW produced significantly greater remineralization (18.4 ± 0.9%) than Orbit (8.9 ± 0.5%) and Orbit Professional (10.5 ± 0.9%).
Conclusion.  The superior remineralization activity of the TW gum in situ was attributed to the presence of casein phosphopeptide–amorphous calcium phosphate nanocomplexes.     

Effect of a xylitol and fluoride containing toothpaste on the remineralization of human enamel in vitro

The aim of this study was to examine the effect of a fluoride and xylitol containing toothpaste on the remineralization of human enamel using Quantitative Light-induced Fluorescence (QLF). Human extracted teeth were cut longitudinally into three or four parts, and artificial subsurface lesion windows (2 mm x 3 mm) were created by immersion in demineralizing solution. Each enamel sample (n = 7) was treated for 3 min at 25 degrees C twice a day for consecutive 14 days with the slurry of a silica-based toothpaste 1) without F- and xylitol (blank), 2) with 500 ppm F- and 3) with 500 ppm F- and 5% xylitol toothpaste. In addition, we measured the remineralization ability of a commercially available toothpaste 4) with 500 ppm F-. The average fluorescence loss F (%) and lesion size (mm2) were determined with QLF. Another variable, delta Q, which was defined as the fluorescence loss integrated over the lesion size (%, mm2), was calculated. The results showed that the combination of 500 ppm F- and 5% xylitol toothpaste significantly (P < 0.05) recovered both the size and delta Q compared to the other groups. These findings suggested that inclusion of xylitol in fluoride toothpaste might be useful to enhance the remineralization in vivo.     

Influence of salivary macromolecules and fluoride on enamel lesion remineralization in vitro

The aim of this study was to investigate the influence of salivary macromolecules on enamel lesion remineralization in the presence or absence of fluoride. Paraffin-stimulated whole saliva was centrifuged, and the supernatant was dialyzed in 1,000 molecular-weight cutoff dialysis tubes, first against a phosphate buffer and then against a mineral solution containing Ca and phosphate. Artificial subsurface lesions of human enamel, created in pH 4.5 acetate buffer, were remineralized for 28 days in 4 remineralizing solutions: group C--mineral solution as a control; group S--mineral solution + dialyzed saliva; group F--mineral solution + 1 ppm F; group SF--mineral solution + dialyzed saliva + 1 ppm F. Changes in relative mineral concentration in the lesions were assessed by transverse microradiography. The results showed statistically significant mineral gains in the lesion body in groups C (DeltaZ = 3,254 +/- 1,562% x microm) and SF (DeltaZ = 2,973 +/- 1,349% x microm), but not in groups S (DeltaZ = 5,192 +/- 1,863% x microm) and F (DeltaZ = 4,310 +/- 1,138% x microm) compared with the baseline group (DeltaZ = 5,414 +/- 461% x microm). It was also found that the mineral density at the surface layer in group F (75.0 +/- 15.7%) was greater than that in the baseline group (30.1 +/- 12.3%) with statistical significance, but not in group SF (39.9 +/- 16.5%). It was concluded that the macromolecules inhibited lesion remineralization fundamentally but that these molecules, in the presence of fluoride, seemed to play an important role in the continuation of remineralization by reducing mineral gains at the surface layer.     

The anticariogenic effect of sugar-free gum containing CPP-ACP nanocomplexes on approximal caries determined using digital bitewing radiography

This study investigated, using digital bitewing radiography, the progression and regression of approximal caries in adolescent subjects chewing a sugar-free gum containing 54 mg CPP-ACP relative to the identical gum without CPP-ACP. 2,720 subjects from 29 schools were randomly assigned to one of the two gums and were instructed to chew their assigned gum for 3 x 10 min/day, with one session supervised on school days, over the 24-month study period. Standardized digital bitewing radiographs were taken at the baseline and 24-month clinical examinations for each subject. The radiographs, scored by a single examiner, were assessed for approximal surface dental caries at both the enamel and dentine level. Surface level transitions were scored using a transition matrix. Caries progression or regression was analysed using proportional-odds ordered logistic regression modelling of the transition scores at the tooth surface level. There was a statistically significant difference in the frequency distributions of the transition scores between the two gum groups (OR = 0.82, p = 0.03). For subjects chewing the CPP-ACP gum the odds of a surface experiencing caries progression were 18% less than those of a surface experiencing caries progression for subjects chewing the control gum. In conclusion, the 54 mg CPP-ACP sugar-free gum significantly slowed progression and enhanced regression of approximal caries relative to a control sugar-free gum in a 24-month clinical trial.     

微量元素矿化液再矿化效果的体内研究

目的　选择体外实验证实具有较强的促进釉质早期龋再矿化作用的微量元素矿化液 ,评价其在体内的脱矿及再矿化效果。方法　制备含 2mm× 2mm正常和人工龋釉质块的可摘口内装置 ,将其置于受试者口内 ,采用激光共聚焦技术观察罗丹明B荧光染料渗透进入多孔釉质荧光量的多少 ,量化受试者在使用不同矿化液前后的再矿化效果 ,用ΔZa、ΔZb 及ΔZ(Zb 与ΔZa 的差值 )来表示 ,具体包括测釉质块荧光量的面积 (Areaofthefluorescentlesion ,A)、总的荧光量 (totalfluorescence ,TF)及病损的平均荧光量 (averagefluorescent,AF) 3个共聚焦参数。结果　受试者口内装置经含氟矿化液和微量元素矿化液处理后脱矿釉质块的共聚焦参数ΔZa 与处理前的ΔZb 相比差异有显著性 (P <0 0 5) ,尤以微量元素组明显。其激光共聚焦结果为 ,ΔZ :A =(- 50 4± 8 1 ) μm2 ,TF =- 2 7 8± 3 8,AF =- 91 5± 8 9,说明微量元素矿化液在体内仍能获得比单纯含氟矿化液更好的促进早期龋再矿化的效果。结论　微量元素矿化液有完善现有含氟矿化液防治早期龋的潜力 ,为临床的进一步应用奠定基础 ,为脱矿和再矿化研究提供了新方法     

Effect of chewing gum containing sodium bicarbonate on human interproximal plaque pH

The effect of chewing sorbitol gum containing sodium bicarbonate on interproximal plaque pH was determined by use of an ion-sensitive field-effect transistor (ISFET) electrode system with four human volunteers. Plaque pH was lowered by 2 min of chewing of a sucrose-containing toffee. After 20 min, either sodium bicarbonate or control gum was chewed for 10 min, and the pH was followed for an additional 20 min. The minimum pH after toffee chewing was elevated by both the control gum (4.5 +/- 0.3 to 5.2 +/- 0.5) and the sodium-bicarbonate-containing product (4.3 +/- 0.3 to 6.1 +/- 0.6) to levels which were significantly different (p less than 0.01). The rate of rise in pH was 2.6 times faster with the gum containing buffer compared with the control gum. In comparison with the control gum, the sodium bicarbonate gum caused the pH to remain at a higher level, approximately 0.5 pH units, for 20 min after gum chewing. The addition of sodium bicarbonate to gum containing sorbitol markedly enhanced its capacity to cause and maintain an elevation of interproximal plaque pH previously lowered by exposure to fermentable carbohydrate. Sodium bicarbonate may be useful in products designed to reduce the acidogenic challenge to the teeth following food ingestion.     

The use of low-tack chewing gum for individuals wearing orthodontic appliances

A clinical study was carried out to determine the acceptability of a sugar-free, low-tack chewing gum by orthodontic patients undergoing fixed appliance treatment. Twenty-five orthodontic and 25 non-orthodontic control subjects were questioned on their preference between regular-tack and low-tack chewing gum. The orthodontic subjects showed a strong preference for the low-tack gum compared with the regular-tack gum. It was concluded that low-tack, sugar-free chewing gum can be used by orthodontic patients to increase saliva flow, with the potential to promote remineralization and help reduce white spot lesion formation related to fixed orthodontic appliances. This gum should also be of value in patients being treated for xerostomia who are wearing a partial denture.     

Delivery of active agents from chewing gum for improved remineralization

Most surrogate measures of caries were developed to test products containing fluoride, typically at relatively high and closely controlled oral concentrations. However, since the primary mechanism for the remineralization of early enamel caries lesions by chewing gum is through stimulation of saliva, delivering Ca and Pi to the demineralized enamel lesion, established methods may lack the sensitivity to detect the additional benefit of an active agent without the strong remineralizing potential of fluoride. Issues related to the release of active agents from the gum matrix, dilution in the saliva, and limited oral retention time, along with taste, safety, regulatory, and cost concerns, impose further limitations. This paper reviews the efficacy of some active agents used in chewing gum for improved remineralization and includes results from in situ testing of calcium-containing gums, including calcium lactate, tetracalcium phosphate/dicalcium phosphate anhydrous, calcium citrate/encapsulated phosphate, and a calcium lactate/sodium phosphate blend. Despite promising in vitro data from these agents, they did not provide consistently superior results from in situ testing. There is a need to develop better predictive in vitro models for chewing gum, as well as improved sensitivity of in situ models to discriminate relatively small amounts of remineralization against a background of high biological variability.     

Anticaries potential of a fluoride mouthrinse evaluated in vitro by validated protocols

This blind and randomized study tested in vitro, using validated protocols, the anticaries potential of an experimental fluoride mouthrinse. One-hundred enamel slabs, half sound and half with caries-like lesions (carious), all with known surface microhardness (SMH), were submitted to 3 treatment groups: A) a placebo mouthrinse (negative control); B) a positive control mouthrinse containing 0.05% NaF; and C) an experimental formulation containing 0.05% NaF and cetylpyridinium chloride as an antibacterial substance. To evaluate the formation of F products on enamel, sound (n=10) and carious (n=10) slabs were treated with the formulations during 10 min and loosely and firmly-bound F formed in enamel were determined after extraction with alkali and acid, respectively. To evaluate the inhibition of enamel demineralization, sound enamel slabs (n=10) were treated with the mouthrinse formulations 2x/day during 1 min and subjected to a pH-cycling regimen simulating a cariogenic challenge (demineralization). To evaluate enamel remineralization, the carious slabs (n=10) were submitted to the treatments 3x/day and subjected to a pH-cycling model simulating a remineralizing condition. After 8 days, enamel SMH was determined again and the percentage of SMH loss or SMH recovery was calculated for the sound and carious slabs, respectively. The experimental formulation was superior to the negative control (p<0.05) and equivalent to the positive control (p>0.05) in the formation of F products in enamel, and in the inhibition of enamel demineralization and enhancement of remineralization. These data suggest that the tested experimental fluoride mouthrinse has anticaries potential.     

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。