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Five new formulations of water ice lollies with a high-phosphorus (low Ca) supplementation ratio were tested for their erosiveness of dental enamel or hydroxylapatite in vitro. Compared with the basic unsupplemented lolly, all five formulations that had been prepared with additional calcium and phosphorus, but in a low Ca/P ratio, as potential inhibitors of demineralisation, were associated with significantly less attack on dental mineral, as measured by the dissolution of calcium and phosphorus.

The composition and dental properties of eight different soft drinks, representing some of the most popular types used in the U.K., were examined. Demineralisation experiments were conducted on hydroxylapatite, the basic component of dental enamel, determining calcium dissolving by atomic absorption spectroscopy and phosphorus by UV/vis spectrophotometry. The titratable acid content of the drinks was found to give a better guide than their pH to their potential dental erosiveness. The sugars content, in their ready-to-drink form, varied from zero in a low-calorie product up to almost 14% in a black-currant drink, but using a technique with a relatively long contact time, and in the absence of intact dental plaque, the demineralising action on hydroxylapatite of the acids already in the drinks eclipsed the effects of the acid generated by oral micro-organisms from the sugars in the drinks. The pure citrus juices showed potentially the worst dental properties, followed by the orange and blackcurrant concentrates after dilution to their ready-to-drink form, with least demineralisation from the carbonated drinks, and a cola drink giving especially low figures.

The composition and dental properties of eight different soft drinks, representing some of the most popular types used in the UK, were examined. Demineralization experiments were conducted on hydroxylapatite, the basic component of dental enamel, determining calcium dissolving by atomic absorption spectroscopy and phosphorus by u.v. visual spectrophotometry. The titratable acid content of the drinks was found to give a better guide than their pH to their potential dental erosiveness. The sugar content, in their ready-to-drink form, varied from zero in a low-calorie product up to almost 14% in a blackcurrant drink, but using a technique with a relatively long contact time, and in the absence of intact dental plaque, the demineralizing action on hydroxylapatite of the acids already in the drinks eclipsed the effects of the acid generated by oral micro-organisms from the sugars in the drinks. The pure citrus juices showed potentially the worst dental properties, followed by the orange and blackcurrant concentrates after dilution to their ready-to-drink form, with least demineralization from the carbonated drinks, and a cola drink giving especially low values.

Boiled sweets formulated with Lycasin were compared with conventional sugar-base sweets. Incubated in media containing solutions of the sweets, mixed cultures of oral microorganisms produced less polysaccharide and acid, with significantly less demineralizing action on dental enamel and hydroxylapatite, from the Lycasin than from the sugar-base products. In comparison with these differences, the effects of changing the flavouring acid combination in the sweets were minor, but levels of citric and malic acids as high as 1.00% showed some inhibition of the activity of the oral microorganisms.

Fluoride is a key dentifrice ingredient for mitigating dental erosion and promoting remineralisation in tooth enamel. A dentifrice formulation (NaF/CL ‐ where C = Copolymer, L = Lactate), optimised for fluoride delivery, containing sodium fluoride, polyvinylmethylether–maleic anhydride (PVM/MA) copolymer and lactate ion at controlled pH of 6.2 is compared with six commercial dentifrices from European and US regulatory regions. The in vitro study utilised white light interferometry (WLI) and dynamic secondary ion mass spectrometry (DSIMS) to assess dental erosion resistance and remineralisation potential of the dentifrices. For WLI, polished enamel samples were immersed in dentifrice slurry (1:3 wt./wt. in artificial saliva, 2 min), brushed, washed in deionised water, acid challenged (1% citric acid, pH 3.8, 5 min), washed and air dried. Surface roughness and bulk tissue loss were measured. DSIMS samples for fluoride uptake were acid challenged (1% citric acid, pH 3.8, 5 min), rinsed, immersed in dentifrice slurry (1:3 wt./wt. in artificial saliva, 2 min), washed and air dried. DSIMS samples for 44Ca uptake were prepared similarly but with 44Ca‐doped artificial saliva. The NaF/CL dentifrice provided highest protection against dental erosion, with highest fluoride and 44Ca uptake in all treatment groups (n = 5 per group). Dentifrices containing other fluoride salts and/or ingredients known to inhibit fluoride uptake (e.g., polyphosphates, sodium lauryl sulfate), performed significantly worse. [ABSTRACT FROM AUTHOR]

Maltodextrin is a hydrolysate of cornstarch and has been widely used in the food industry associated with sucrose. The addition of starch can increase the cariogenic potential of sucrose; however, there are sparse data regarding the cariogenicity of sucrose associated with maltodextrin. Therefore, the aim of this study was to test in situ if maltodextrin could increase the cariogenic potential of sucrose. This was an in situ, randomized, crossover, split-mouth, and double-blind study. Volunteers wore palatal appliances containing bovine enamel blocks for 2 periods of 14 days. They dripped the following solutions on the enamel blocks 8 times per day: deionized distilled water (DDW), maltodextrin (M), sucrose + maltodextrin (S+M), or sucrose (S). At the end of each experimental period, biofilms were collected and analyzed for microbiological (mutans streptococci, lactobacilli, and total microorganisms counts) and biochemical (calcium, inorganic phosphate, fluoride, and insoluble extracellular polysaccharides concentrations) compositions. The enamel demineralization was assessed by microhardness. Treatments S and S+M resulted in a lower inorganic composition and higher concentration of insoluble extracellular polysaccharides in the biofilms, and higher enamel mineral loss compared to DDW and M. It can be concluded that the cariogenic potential of sucrose is not changed when this carbohydrate is associated with maltodextrin (dextrose equivalent 13-17). [ABSTRACT FROM AUTHOR]

Carbonated beverages are becoming immensely popular among individuals. These drinks are one of the major contributing factors which lead to the dissolution of apatite crystals of enamel. Study the effects of different carbonated drinks on the labial surface of enamel and its esthetic outcomes. The objective differences of various drinks are examined and evaluated under SEM. Twelve extracted anterior teeth were selected and thoroughly cleansed for debris and disinfected by sodium hypochlorite for 24 hours. Distributed into four groups, these samples were submerged into different carbonated drinks (Pepsi, carbonated juice-Big Apple, Sports drink-Sting, control group-natural saliva) each for 5min, in 4 cycles per day (6 hours apart) for 15 days. The samples from the control group were exposed to natural saliva during experimentation. Throughout the experiment the samples were stored in Saline (0.9% W/V NaCl). This storage medium was changed on daily basis and in each cycle a new chilled (at 3-4°C) bottled drink was used. Samples were dried under a lamp keeping a safe distance of 15cm, coated with Aurum (gold) foil to be examined under the JSM- 5200 Scanning Electron Microscope (JEOL, Tokyo, Japan) at 20kV and were then photographed at different magnitudes. The SEM images show rough enamel surface which is due to the acidic content (phosphoric acid and citric acid) of Pepsi, carbonated drink and sports drink. As the samples were immersed in (NaOCl) for 24 hours, it is expected that micro pores noticed in the images from control group were developed due to this initial immersion. It is reported that NaOCl create 3-8 micron pores on the surface of tooth after immersion. It was concluded acidic soft drinks induce roughness on the enamel, which eventually reduces the mechanical and physical properties of the structure. These changes in physical properties render the enamel more vulnerable to staining, fracturing and developing of caries. [ABSTRACT FROM AUTHOR]

This study aimed to examine the surface characteristics of erosive enamel in extracted human teeth by scanning electron microscopy. Morphologic changes in naturally eroded enamel depend on the stages of dental erosion. In its early stages, the enamel surfaces show a honeycomb appearance due to the dissolution of enamel rod ends. In its advanced stages, the erosive process involves the underlying dentin and the eroded dentin shows exposed dentinal tubules and the dentinal matrix may be exposed due to the dissolution of the peri- and intertubular dentin. Evidence of remineralization is seen at the early stage of natural dental erosion. [ABSTRACT FROM PUBLISHER]

Aim: This study evaluates erosive potential of commonly used beverages, medicated syrup, and their effects on dental enamel with and without restoration in vitro. Materials and Methods: Test medias used in this study included carbonated beverage, noncarbonated beverage, high-energy sports drink medicated cough syrup, distilled water as the control. A total of 110 previously extracted human premolar teeth were selected for the study. Teeth were randomly divided into two groups. Test specimens were randomly distributed to five beverages groups and comprised 12 specimens per group. Surface roughness (profilometer) readings were performed at baseline and again, following immersion for 14 days (24 h/day). Microleakage was evaluated. The results obtained were analyzed for statistical significance using SPSS-PC package using the multiple factor ANOVA at a significance level of P < 0.05. Paired t-test, Friedman test ranks, and Wilcoxon signed ranks test. Results: For surface roughness high-energy sports drink and noncarbonated beverage showed the highly significant difference with P values of 0.000 and 0.000, respectively compared to other test media. For microleakage high-energy sports drink had significant difference in comparison to noncarbonated beverage (P = 0.002), medicated syrup (P = 0.000), and distilled water (P = 0.000). Conclusion: High-energy sports drink showed highest surface roughness value and microleakage score among all test media and thus greater erosive potential to enamel while medicated syrup showed least surface roughness value and microleakage among all test media. [ABSTRACT FROM AUTHOR]

Erosion is a highly prevalent condition known as a non-carious lesion that causes progressive tooth wear due to chemical processes that do not involve the action of bacteria. Speckle images proved sensitive to even minimal mineral loss from the enamel. The aim of the present study was to investigate the use of laser speckle imaging analysis in the spatial domain to quantify shifts in the microstructure of the tooth surface in an erosion model. 32 fragments of the vestibular surface of bovine incisors were divided in for groups (10 min, 20 min. 30 min and 40 min of acid etching) immersed in a cola-based beverage (pH approximately 2.5) twice a day during 7 days to create an artificial erosion. By analyzing the laser speckle contrast map (LASCA) in the eroded region compared to the sound it was observed that the LASCA map shifts, proportionally to the acid each duration, by: 18%; 23%; 39% and 44% for the 10 min; 20 min; 30 min and 40 min groups, respectively. To the best of our knowledge, this is the first study to demonstrate the correlation between speckle patterns and erosion progression. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate the effectiveness of dentifrices containing high concentrations of sodium fluoride (NaF) and casein phosphopeptide-amorphous calcium phosphate cream plus fluoride (CPP-ACPF) in prevention of the erosion in a simulated oral environment study model. Subjects and Methods: Fifteen flat human enamel specimens were polished and half of the surfaces were protected with adhesive tape. Initial Knoop microhardness (KHN) and surface roughness (SR) were measured, and specimens were assigned to four groups: Control (placebo toothpaste - G1); CPP-ACPF (G2), NaF 1450 ppm (G3), and NaF 5000 ppm (G4). Enamel surfaces were brushed 3 times daily in association with demineralization-remineralization cycles (5s in cola drink + 5s in artificial saliva/10 cycles/twice daily) and the specimens were maintained in a salivary flow simulator apparatus. After 14 days, KHN and SR were measured again, and the enamel surfaces were analyzed by scanning electronic microscopy (SEM). Statistical Analysis Used: Data were analyzed using the two-way ANOVA and Student-Newman- Keuls multiple range test (α =0.05). Results: All the tested groups presented a decrease in KHN after 14 days (P < 0.05). There was no statistical significance among materials tested. Significant increase in SR was observed for all groups. SEM analysis showed morphological alterations with honeycomb structures in enamel surfaces in the four experimental groups. Conclusions: It was concluded that tooth brushing with dentifrices with high concentration of NaF and CPP-ACPF cream was not able to prevent enamel erosion in simulated oral environment. [ABSTRACT FROM AUTHOR]

The article discusses whether the prevention of dental caries can benefit substantially from the development of functional foods or foods with components that may provide a health benefit beyond basic nutrition. Some of the natural food constituents and plant extracts with anticaries properties include tea, cocoa, cranberry, apple, grapes and wine, coffee and raisins. Several benefits of artificial sweeteners, dairy products as well as probiotics in preventing caries are highlighted.

The aim of this study was to evaluatethe erosive potential of orange juice modified with food-approved additives: 0.4 g/l of calcium (Ca) from calcium lactate pentahydrate, 0.2 g/l of linear sodium polyphosphate (LPP) or their combination (Ca+LPP) were added to a commercially available orange juice (negative control, C-). A commercially available calcium-modified orange juice (1.6 g/l of calcium) was the positive control (C+). These juices were tested using a short-term erosion in situmodel, consisting of a five-phase, single-blind crossover clinical trial involving 10 subjects. In each phase, subjects inserted custom-made palatal appliances containing 8 bovine enamel specimens in the mouth and performed erosive challenges for a total of 0 (control), 10, 20, and 30 min. Two specimens were randomly removed from the appliances after each challenge period. Enamel surface microhardness was measured before and after the clinical phase and the percentage of surface microhardness change (%SMC) was determined. Before the procedures, in each phase, the subjects performed a taste test, where the juice assigned to that phase was blindly compared to C-. Overall, C+ showed the lowest %SMC, being the least erosive solution (p < 0.05), followed by Ca+LPP and Ca, which did not differ from each other (p > 0.05). LPP and C- were the most erosive solutions (p < 0.05). Taste differences were higher for C+ (5/10 subjects) and Ca (4/10 subjects), but detectable in all groups, including C- (2/10 subjects). Calcium reduced the erosive potential of the orange juice, while no protection was observed for LPP. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Excessive consumption of acidic drinks and foods contributes to tooth erosion. The aims of the present in vitro study were twofold: (1) to assess the erosive potential of different dietary substances and medications; (2) to determine the chemical properties with an impact on the erosive potential. We selected sixty agents: soft drinks, an energy drink, sports drinks, alcoholic drinks, juice, fruit, mineral water, yogurt, tea, coffee, salad dressing and medications. The erosive potential of the tested agents was quantified as the changes in surface hardness (ΔSH) of enamel specimens within the first 2 min (ΔSH2–0 = SH2 min − SHbaseline) and the second 2 min exposure (ΔSH4–2 = SH4 min − SH2 min). To characterise these agents, various chemical properties, e.g. pH, concentrations of Ca, Pi and F, titratable acidity to pH 7·0 and buffering capacity at the original pH value (β), as well as degree of saturation (pK − pI) with respect to hydroxyapatite (HAP) and fluorapatite (FAP), were determined. Erosive challenge caused a statistically significant reduction in SH for all agents except for coffee, some medications and alcoholic drinks, and non-flavoured mineral waters, teas and yogurts (P < 0·01). By multiple linear regression analysis, 52 % of the variation in ΔSH after 2 min and 61 % after 4 min immersion were explained by pH, β and concentrations of F and Ca (P < 0·05). pH was the variable with the highest impact in multiple regression and bivariate correlation analyses. Furthermore, a high bivariate correlation was also obtained between (pK − pI)HAP, (pK − pI)FAP and ΔSH. [ABSTRACT FROM PUBLISHER]

Initial dental erosion - the very first tooth surface changes caused by short-term acidic exposures before any tissue loss is observed - has been studied using in vitro and in situ/in vivo protocols. This paper describes the events that should be considered when modelling initial erosion, the available protocols and their strengths and limitations. In vitro initial erosion models can provide relevant information about the erosive outcome. However, the published studies vary considerably regarding the erosive parameters used, and few of these studies have been validated. On the other hand, relevant in situ/in vivo studies are available that have studied the effect of salivary pellicle and preventive treatments on initial erosion, as well as the changes in salivary pH following exposure to acid solutions. Guidelines for good methodology in modelling initial erosion are proposed. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The advantages, limitations and potential applications of available methods for studying erosion of enamel and dentine are reviewed. Special emphasis is placed on the influence of histological differences between the dental hard tissue and the stage of the erosive lesion. No method is suitable for all stages of the lesion. Factors determining the applicability of the methods are: surface condition of the specimen, type of the experimental model, nature of the lesion, need for longitudinal measurements and type of outcome. The most suitable and most widely used methods are: chemical analyses of mineral release and enamel surface hardness for early erosion, and surface profilometry and microradiography for advanced erosion. Morphological changes in eroded dental tissue have usually been characterised by scanning electron microscopy. Novel methods have also been used, but little is known of their potential and limitations. Therefore, there is a need for their further development, evaluation, consolidation and, in particular, validation. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The influence of beverage composition on the measurement of erosive potential is unclear. The aim of this study was to evaluate whether beverage composition influences the measurement of erosive potential and to evaluate the influence of exposure in small and large volumes. Eleven beverages were included: water (control), 3 alcopops, 2 beers and 5 soft drinks. For each beverage 15 bovine enamel samples were used: 5 for chemical and 10 for profilometric analysis. After exposure to the beverages (63 min) the resulting solutions were analyzed for Ca and inorganic phosphorus (Pi) content. The samples for optical profilometry were submersed sequentially in 500 ml or in 1 ml of the drinks for 3, 6, 9, 15 and 30 min (total 63 min). For some of the beverages high baseline concentrations of Ca (energy drink) or Pi (cola drink, cola lemon drink, beer, beer lemon) were found. Some of the beverages showed a good correlation between the chemical methods. Profilometry (both for 1 and 500 ml) showed generally lower enamel losses than the chemical methods. Lower enamel losses were found for the profilometry 1 ml compared to the profilometry 500 ml only for the cola drinks. It can be concluded that the composition of the beverages had a significant effect on the determination of the erosive potential with chemical analyses. Drink composition also influenced the effect of small versus large exposure volumes, indicating the need for standardization of exposure parameters. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Aim. This study evaluated the action of an antihistamine-containing syrup (Claritin D) on enamel that was subsequently submitted or not to applications of fluoride dentifrice. Methods. Two hundred sixty-four slices ( n = 44 per subgroup) prepared from exfoliated primary molars were evaluated in hardness tests. Six subgroups were submitted to different treatments for 10 days. The controls underwent pH cycling with (positive control) or without (negative control) three daily immersions in fluoride dentifrice/distilled water slurry. The test subgroups related to daytime use of the antihistamine syrup underwent pH cycling and two 5-min applications of Claritin D, coupled or not to the three daily immersions in the fluoride slurry. The subgroups related to nocturnal use of the syrup were submitted to the same procedures of daytime subgroups, respectively, but with one of the applications of Claritin D lasting for 8 h. Results. The median hardness values obtained after use of the syrup were significantly lower than the initial ones. Equivalent values for subgroups submitted to fluoride applications in addition to treatment with the syrup were significantly higher. Conclusion. It was concluded that the antihistamine-containing syrup reduced the hardness of primary enamel and that, in this experiment, the use of fluoride dentifrice was able to diminish this erosive effect. [ABSTRACT FROM AUTHOR]

The aim was to investigate the anti-caries properties of calcium glycerophosphate (CaGP) using an in vitro bacterial flow cell model. Four flow cells, inoculated from a chemostat containing a seven-organism bacterial consortium, were pulsed with sucrose twice daily, to provide an acidic challenge and pH-cycling conditions. Blocks of enamel and dentine were mounted in each flow cell. In a study on the effect of CaGP concentration, CaGP was pulsed into three of the flow cells, at the same time as the sucrose, to give concentrations of 0.10, 0.25 and 0.50%. Water was pulsed into the fourth flow cell with the sucrose. Microradiography revealed a significant dose response of decreasing demineralization as CaGP concentration increased. Reductions at 0.25 and 0.5% were significant when compared to the control. A second study investigated the effect of timing of CaGP pulsing, relative to sucrose, on enamel and dentine demineralization. CaGP (flow cell concentration 0.2%), was pulsed 1 h before, during or 1 h after the sucrose pulse; a water control was employed. In enamel, pulsing CaGP before the sucrose reduced demineralization significantly compared to concurrent pulsing, which in turn gave a significant reduction compared to pulsing after sucrose, which did not reduce demineralization significantly compared to the water control. In dentine, CaGP reduced demineralization significantly only when pulsed before the sucrose. The findings suggest that in vivo, the anti-caries potential of CaGP may be greater if it is applied before a cariogenic challenge. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether a tooth cream containing casein/calcium phosphate (CasCP) protects enamel against erosion. Sixty bovine enamel specimens were prepared for profilometry and distributed into five groups. Specimens were rinsed with artificial saliva interrupted by 1% citric acid (pH 2.3) for 30 s 6 times daily for 14 days. Group 1 (n = 12) was not treated (control); in group 2 (n = 12) CasCP was applied for 120 s twice daily; in group 3 (n = 12) 250 ppm fluoride as NaF was applied for 120 s twice daily; in group 4 (n = 12) CasCP was applied for 120 s, then 250 ppm fluoride for 120 s twice daily, and in group 5 (n = 12) amine fluoride (AmF) gel (12,500 ppm fluoride) was applied for 120 s twice daily. Differences between groups with respect to erosive enamel loss (profilometrically determined depth after 7 and 14 days) were tested by the Mann-Whitney test (α = 0.05). After 7/14 days’ erosive cycling, specimens treated with AmF gel showed significantly less enamel loss (18.5/35.5 μm; medians) than those treated with CasCP (25.5/46.9 μm), 250 ppm fluoride (25.0/ 40.9 μm), CasCP and 250 ppm fluoride (23.9/47.4 μm) or with no treatment (26.3/49.8 μm). It is concluded that highly fluoridated acidic AmF gel can protect enamel against erosion while CasCP, 250 ppm fluoride or a combination of CasCP and 250 ppm fluoride provide little protection. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Dental erosion involves dissolution of the hydroxyapatite fraction of enamel and dentine, so agents that reduce the dissolution rate of hydroxyapatite could find application in food products aimed at reducing erosion. This study was performed to test some common food ingredients and additives for their effect on the dissolution rate of hydroxyapatite in a citric acid solution representative of soft drinks. Pyrophosphate, tripolyphosphate and a linear chain polyphosphate (average 25 phosphate units) significantly reduced the hydroxyapatite dissolution rate by 35, 46 and 64%, respectively. Xanthan gum and carboxymethylcellulose significantly reduced the hydroxyapatite dissolution rate by 29 and 16%, respectively. The protective effect may be ascribed to the binding of condensed phosphate or to the formation of an adsorbed layer of gum at the hydroxyapatite surface. Several other common food additives had no statistically significant effect on the hydroxyapatite dissolution rate. Polyphosphate exhibited a considerable persistence of action, causing a reduction in the dissolution rate for 3 h after treatment. Tripolyphosphate was slightly persistent, and pyrophosphate and xanthan gum did not exhibit a substantial persistence of action. A solution containing polyphosphate and xanthan gum reduced the hydroxyapatite dissolution rate by 70% and exhibited a similar persistence of action to the solution containing only polyphosphate. These compounds are suggested to have potential as erosion-reducing agents in soft drinks. [ABSTRACT FROM AUTHOR]

Background: Dental erosion is highly prevalent today, and acidic drinks are thought to be an important cause. The aim of the present investigation was to determine the erosive potential of a range of common beverages on extracted human teeth.Methods: The beverages were tested for their individual pHs using a pH meter. The clinical effects of the most erosive beverages were determined by the degree of etching and Vickers microhardness of enamel.Results: The results showed that many common beverages have pHs sufficiently low to cause enamel erosion. Lime juice concentrate (pH 2.1) had the lowest pH, followed by Coca-cola and Pepsi (both with pH 2.3) and Lucozade (pH 2.5). The erosive potential of these beverages was demonstrated by the deep etching of the enamel after five minutes. The Vickers Hardness of enamel was reduced by about 50 per cent in the case of lime juice (p < 0.001) and 24 per cent in the case of Coca-cola (p < 0.004). Addition of saliva to 50 per cent (v/v) of Coca-cola completely reversed the erosive effects on the enamel.Conclusions: Although only a few of the beverages with the lowest pHs were tested, the present study showed that the most acidic drinks had the greatest erosive effects on enamel. While saliva was protective against erosion, relatively large volumes were required to neutralize the acidity. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effects of salicylic–lactic (SL) acid conditioner on the shear bond strength of brackets. Fluoride releasing (Light-bond) and non-fluoride releasing (Enlight) composite adhesives were used after conditioning with 0·22% salicylic + 9% lactic acid or 34% phosphoric acid. Composite adhesives were light cured with either a halogen light curing (HLC) unit for 30–50 s or a plasma arc curing (PAC) unit for 4 s. The shear bond strength was measured with an Instron. Failure modes of debonded brackets were identified based on adhesive remnants on the bracket and tooth. Salicylic–lactic acid conditioning was found to provide adequate shear bond strength. Groups conditioned with SL acid were debonded mainly at the enamel–resin interface and comparatively clean enamel surface after debonding was observed than those conditioned with phosphoric acid. Using confocal laser scanning microscopic examinations, it was found that demineralization patterns between SL acid and phosphoric acid conditioned groups were not different when the same adhesive was used. The SL acid conditioner did not reduce the demineralization. Light-bond adhesive showed less demineralization than Enlight adhesive. The PAC unit can be recommended as an alterative to the HLC unit because it significantly reduces the irradiation time. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to evaluate the effects of various proteins onin vitrodemineralization of bovine enamel. From each of 100 bovine incisors two samples were prepared. The specimens were embedded in epoxy resin and polished up to 4000 grit. Subsequently, the specimens’ surfaces were partly covered with nail varnish, thus serving as control of sound enamel. The specimens were divided randomly into five groups (n = 40) and demineralized in a solution of constant composition (pH 5·0; 10 days). For each subgroup of specimens (n = 10) 4 L were taken and either low (50% of medium conc.), medium, or high (150%) concentrations of the proteins [human albumin (100% conc. = 7 mg L−1), mucin (577·5 mg L−1), immunoglobulin G (IgG) (46 mg L−1), casein isolated from bovine milk (1·2 g L−1)] or amino acid [l-Proline (7 mg L−1)] were added to 1 L of the demineralizing solution, whereas 1 L served as control. Mineral loss and lesion depth (LD) were evaluated from microradiographs of thin sections (110 μm) by a dedicated software package (TMR 1.24). No differences were found between the five control groups (P > 0·05;anova). Albumin,l-Proline, and IgG did not affect enamel demineralization, whereas the addition of both casein and mucin resulted in significant reductions of both mineral loss and LDs (P < 0·01; Tukey's test). Within the limitations of anin vitrostudy, the present investigation indicates that casein and mucin seem to affect enamel demineralization significantly. Thus, these proteins might be helpful as an additive to saliva substitutes or mouthwashes if the quality of saliva is altered. [ABSTRACT FROM AUTHOR]

To evaluate the enamel erosive potential of modified acidic soft drinks under controlled conditions in an artificial mouth.From each of 144 bovine incisors one enamel sample was prepared. Labial surfaces of the samples were ground flat, polished and covered with adhesive tape, leaving an exposed area. The samples were distributed among four (A–D) groups for treatment with A: Coca-Cola, B: Sprite; C: Sprite light, D: orange juice. Either 1.0 mmol l−1 calcium (Ca) or a combination (comb.) of 0.5 mmol l−1 calcium plus 0.5 mmol l−1 phosphate plus 0.031 mmol l−1 fluoride was added to the beverages. Samples of each group were subdivided into three subgroups (-original; -Ca and -comb.) for treatment with original and modified drinks. De- and remineralization cycles were based on a standard protocol described earlier. Surface loss of the specimens was determined using profilometry after test procedure.In all subgroups, loss of enamel was observed. The enamel loss recorded for the samples rinsed with original Sprite and original orange juice was significantly higher compared with all other solutions (P = 0.001). Lowest enamel loss was recorded for the original Coca-Cola group (P = 0.001). With the exception of Coca-Cola, demineralization with the modified beverages led to significantly lower losses compared with the respective original solutions.Modification of the test soft drinks with low concentrations of calcium or a combination of calcium, phosphate and fluoride may exert a significant protective potential with respect to dental erosion. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate dental erosion in 0.1 and 1.0% citric acid in vitro by several different methods and to assess the protective potential of experimentally formed salivary pellicle (24 h in vitro). Bovine enamel slabs were embedded in epoxy resin and polished. Erosion was performed in citric acid for 1, 5 or 10 min and recorded as microhardness loss, as changes of surface roughness (R(a), R(t) and R(zDIN)) and as calcium release. Additionally, erosive alterations were observed with scanning electron microscopy. Significant microhardness loss on non-pellicle-covered specimens was measured after 1-min exposure to 0.1% citric acid. Microhardness loss was time- and concentration-dependent. Salivary pellicle significantly inhibited both microhardness loss, except after 10-min immersion in 1.0% citric acid, and significantly reduced the increase of surface roughness. There were, however, no significant differences in calcium release between pellicle-covered and non-covered enamel. The results support the general conclusion that salivary pellicle effectively protects enamel surface against short-term erosion in organic acids. [ABSTRACT FROM AUTHOR]

In theory, calcium and phosphate in the plaque fluid exert a large influence on the demineralization of enamel surface. In order to know the effect of increasing the concentration of either of these factors, the following in vitro experiment was conducted. Three thin sections, about 150 μm thick, were cut out from each of 13 human premolars. All surfaces of the sections, except for the original enamel surface, were coated with nail varnish. These sections were immersed into one of two sets of demineralizing solutions for 1 week at 25°C. Each set, the 'calcium set' and the 'phosphate set', contained three solutions. The composition of these solutions differed mainly in calcium or phosphate concentrations. After 1 week, the degree of demineralization was determined by image analysis of contact microradiograms from each section. The subsurface demineralization in enamel was reduced by 95% by increasing the calcium concentration of the demineralizing solution from 7 to 21 mmol/l. A similar reduction (87%) was observed by increasing the phosphate concentration. However, the amount of phosphate needed was approximately 20 times more than that of calcium. The larger inhibitory effect that calcium has on enamel demineralization was related to the larger effect it has on the degree of saturation of the solution. Even though no statistically significant difference was found between the effect of calcium and phosphate on the demineralization of enamel (when the solutions had the same degree of saturation), the difference in the standard deviation of demineralization suggests the existence of some other factors which have an influence on the demineralization reaction. [ABSTRACT FROM AUTHOR]

To assess the erosive effect of a cola drink on enamel incorporating early salivary pellicles, 72 groups of human enamel slabs were immersed in fresh cola, with groups differing in that slabs were (1) incubated in whole or in clarified saliva, (2) under three regimes of frequency intake (1, 5 and 10 times/day); (3) immersed with or without agitation, and (4) the pellicle was incubated for 20 min, 6 or 24 h. Quantitative assessments were done over an 8-day interval using surface microhardness testing. Results for primary enamel showed a sharp decrease from baseline (344.2±32.4 Vickers Units; mean ±SD) to day 1 (268.9±36.8), and reached 155.2±68.6 on day 8. Results for permanent enamel were 350.8±42.2, 315.9±39.2, and 149.8±85.2. Microhardness was affected by agitation, level of intake and type of saliva, but not by the pellicle incubation interval nor the type of enamel. The joint effect of static baths and higher immersion frequency was the most important factor in decreasing hardness. [ABSTRACT FROM AUTHOR]

The capability of a soft drink or a juice to erode dental enamel depends not only on the pH of the drink, but also on its buffering effect. As the latter is the ability of the drink to resist a change of pH it may add to the effects of the actual pH. The aim of the present study was to compare the pH and the buffering effect of various soft drinks with their erosive effects and the solubility of apatite. In 18 soft drinks, mineral waters and juices available on the Danish market, pH and the concentrations of calcium, phosphate and fluoride were determined. The buffering effect was determined by titration with NaOH. Human teeth (n = 54) covered with nail varnish except for 3x4-mm windows were exposed to 1.5 liters of the drink for either 7 days or 24 h under constant agitation. The depth of the erosions was assessed in longitudinal sections. The depth was found to vary greatly from 3 mm eroded by the most acidic drinks and fresh orange juice to only slightly affected surfaces by most of the mineral waters. The dissolution of enamel increased logarithmically inversely with the pH of the drink and parallel with the solubility of enamel apatite. Orange juice, pH 4.0, supplemented with 40 mmol/l calcium and 30 mmol/l phosphate did not erode the enamel as the calcium and phosphate saturated the drink with respect to apatite. Generally, the lower the pH the more NaOH was necessary to bring the pH to neutrality. In particular the buffering effect of the juice was high. For all drinks, no effect of their low fluoride concentrations was observed. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop transverse microradiography (TMR) in order to quantitatively assess the influence of artificial saliva and orange juice on the erosion of bovine enamel. Bovine incisors were sectioned sagittally into two equal halves. Each half was coated with acid-resistant nail varnish except for a rectangular enamel window on the labial surface of the tooth. While both halves of each tooth were immersed in pure orange juice 6 times daily for a period of 5 min at each occasion making a total of 30 min per day, one half was stored in artificial saliva and the other half in deionized distilled water between exposures to orange juice and for the remaining 12 h overnight, for 24 days making a total of 12 h of exposure to orange juice. Sections bearing intact and eroded enamel surfaces were cut from each specimen and ground to 80 microm thickness, and TMR of the sections was made. Mineral loss was quantified from the microradiographs using two-step image analysis. Mineral loss was significantly greater in those specimens cycled in orange juice and de-ionized distilled water. TMR was used successfully to quantify the mineral loss by erosion in vitro, and it is envisaged that it will be useful for specimens used in intra-oral appliances during in situ trials. Artificial saliva saturated with respect to calcium and phosphate salts can possibly remineralize an erosive lesion and may reduce the degree of erosion. [ABSTRACT FROM AUTHOR]

There are several causes of erosion - acidic foods and drinks have been implicated and reducing their erosive potential would seem an important area of research. Calcium-citrate-malate (CCM) appeared to have potentially useful properties as an anti-erosion additive. The study aims were to test the ability of an intra-oral enamel slab system to measure erosion and to compare the erosive potential of a citric acid-based orange juice drink either with or without added CCM and a positive and negative control. Eleven adults wore an upper removable appliance for four periods each of 6 days. Each appliance held two enamel slabs which were inserted into the test drinks for 15 min 4 times a day for 6 days. Loss of enamel was quantified by profiling casts of the enamel slabs taken before and after the test period. Loss of enamal was greatest during exposure to a diet phosphoric acid-based cola drink (p < 0.001) but was similar during exposure to the two citric acid-based orange drinks, with or without CCM, and distilled water. The loss of surface enamel measured from a scanning electron micrograph agreed well with the measurement obtained by profilometry. It can be concluded that (a) the intra-oral enamel slab system was able to discriminate between drinks in their erosive potential, and (b) it was not possible to determine if CCM had any potential for reduction in erosion in an acid beverage as the level of erosion observed for both the critic acid-based orange drinks was not statistically significantly different from that observed with distilled water. [ABSTRACT FROM AUTHOR]

Studies assessing the erosive potential of soft drinks have employed long time intervals of immersion that may not accurately depict the impact of frequent soft drink consumption on enamel. This in vitro study assessed the effect of a cola drink on enamel, replicating an actual drinking pattern. Six groups of 4 human enamel slabs were immersed (5 min each bath) in fresh cola drink, with immersions taking place with or without agitation, and under 3 regimes of frequency intake (low intake, 1 immersion/day; medium, 5/day; high, 10/day). Quantitative assessments of surface erosion were done over an 8-day interval using surface microhardness testing (Vickers). Results showed a sharp decrease from baseline (mean value 352.1 Vickers Hardness Number, SD 32.5) to day 1 (269.3, SD 41.0) and then continued decreasing throughout the assay, although less markedly, to reach 204.5, SD 45.4 on day 8. Microhardness decreased regardless of frequency regime, except on day 8, on which slabs from the low intake group were harder (233.2, SD 25.0) than slabs from the high intake group (169.8, SD 49.5; p < 0.05). Results from the ANOVA on the factorial experiment indicated that the role of agitation was statistically significant (d.f. = 1, F = 7.2, p = 0.020) while the level of intake was of borderline significance (d.f. = 2, F = 3.2, p = 0.075). The main effect resulting from the joint roles of agitation and intake indicated that there was an important interaction between the two variables (d.f. = 3, F = 4.5, p = 0.023). [ABSTRACT FROM AUTHOR]

Dental erosion is caused by acidic solutions which come into contact with the teeth. Because the critical pH of dental enamel is approximately 5.5, any solution with a lower pH value may cause erosion, particularly if the attack is of long duration, and repeated over time. Saliva and salivary pellicle counteract the acid attacks but if the challenge is severe, a total destruction of tooth tissue follows. Ultrastructural studies have shown that erosive lesions are seen in prismatic enamel as characteristic demineralization patterns where either the prism cores or interprismatic areas dissolve, leading to a honeycomb structure. In aprismatic enamel the pattern of dissolution is more irregular and areas with various degrees of mineral loss are seen side by side. In dentin the first area to be affected is the peritubular dentin. With progressing lesions, the dentinal tubules become enlarged but finally disruption is seen also in the intertubular areas. If the erosion process is rapid, increased sensitivity of the teeth is the presenting symptom. However, in cases with slower progression, the patient may remain without symptoms even though the whole dentition may become severely damaged. Regarding the role of causative agents, present data does not allow the ranking of different acids with regard to their potential of causing erosion. Neither is there consensus as to how effective fluorides are in preventing the progression of erosive lesions, or how the chemical and structural factors of tooth tissue in general might modify this pathological process. [ABSTRACT FROM AUTHOR]