The erosive effect of pomegranate juice on enamel: An in vitro study.

AIM: Dental erosion is a chemical-mechanical process that leads to the loss of dental hard tissues. This study aimed to investigate the effect of pomegranate juice on the enamel. METHODS: Enamel blocks were randomly divided into three groups: deionized water, cola, and pomegranate juice. The blocks were immersed in the solutions four times a day for 14 days, and stored in artificial saliva for the remaining period. The surface hardness was measured on days 7 and 14. The surface structures of the demineralized blocks were observed via scanning electron microscopy (SEM), and the depth of demineralization was observed via confocal laser scanning microscopy (CLSM). The pH, calcium, and phosphorus levels of the three solutions were analyzed. RESULTS: The microhardness values of the blocks in the pomegranate juice and cola groups decreased with the increase in the demineralization time. The blocks in the pomegranate juice group exhibited large fractures in the enamel column, whereas those in the cola group had pitted enamels with destruction of the interstitial enamel column. Compared with cola group, fluorescent penetration increased in pomegranate juice (P < 0.01). The pH of cola (2.32 ± 0.09) was lower than that of pomegranate juice (3.16 ± 0.16). Furthermore, the calcium content in pomegranate juice was significantly higher than that in cola (P < 0.01). Alternatively, the concentration of phosphorous in cola was significantly higher than that in pomegranate juice (P < 0.01). CONCLUSION: These findings indicate that pomegranate juice can cause enamel demineralization with an erosive potential comparable to that of cola.

Dental erosion following clopidogrel administration in a dog: A case-based study.

A 10-year-old neutered male Chihuahua presented with unilateral dental erosion that occurred after several months of oral medications mixed with honey. A pH test was performed on all oral medications administered to the dogs to determine the cause of enamel erosion. Among the medications, the only acidic medication was clopidogrel (pH 2.65). To evaluate the effect of clopidogrel on the tooth surface under the same conditions as in the present patient, an additional preliminary study was designed in which two extracted teeth of another dog were immersed in a clopidogrel-honey mixture or only in honey. After a 3-week soaking of the extracted tooth in the clopidogrel-honey mixture, field-emission scanning electron microscope analysis revealed a rougher surface, whereas energy-dispersive X-ray spectroscopy analysis showed a reduced Ca/C ratio compared to the control tooth. In this case, prolonged exposure of the tooth surface to clopidogrel may be a cause of dental erosion.

The effect of location/site on polished human enamel after mechanical and chemical wear.

OBJECTIVE: To compare profilometry and microhardness of polished occlusal and buccal human enamel following a mechanical and chemical wear regime. METHODS: Enamel from polished human molars were sectioned into buccal and occlusal surfaces and randomly allocated into two groups (n = 10) and then exposed to 0.3 % citric acid at pH 2.7 for 10, 20, 40 and 60 mins each followed by abrasion with non-fluoridated toothpaste for 240 strokes in a reciprocating brushing machine. A white light profilometer with a spot size of 12 um measured mean step-height following each cycle. Microhardness indentations were conducted following the final cycled 60 mins erosion/abrasion using 0.01, 0.02, 0.1, 0.5 and 2.5 kgf indentation load. Statistical disparity were evaluated using a two-way ANOVA and post-hoc Sidak's multiple comparisons tests at α = 0.05. RESULTS: After erosion/abrasion, the mean (SD) step-heights on occlusal and buccal surfaces were not significantly different until 60 mins, when occlusal surfaces exhibited greater step-heights, 32.9 µm (2.8) and 31.1 µm (1.8) and p = 0.02, respectively. Buccal and occlusal microhardness was statistically lower following erosion/abrasion at loads of 0.01 kgf (p = 0.0005) and 0.02 kgf (p = 0.0006) but no significant differences were observed in the microhardness between the surfaces at any loads. CONCLUSION: The occlusal and buccal surfaces were not statistically different for microhardness or step height suggesting the susceptibility to wear is not related to the anatomy and structure of the tooth and is more likely related to other factors such as the environment. CLINICAL SIGNIFICANCE: The study emphasizes that a notable difference in wear between occlusal and buccal enamel surfaces emerges only after prolonged exposure to simultaneous chemical and mechanical stress. This finding necessitates a preventive dental approach that accounts for both the duration of exposure and environmental factors.

The subsurface lesion in erosive tooth wear.

OBJECTIVES: This study compared the surface change on natural and polished enamel exposed to a joint mechanical and chemical wear regimen. METHODS: Human enamel samples were randomly assigned to natural (n = 30) or polished (n = 30) groups, subjected to erosion (n = 10, 0.3% citric acid, 5 min), abrasion (n = 10, 30 s), or a combination (n = 10). Wear in the form of step height was measured with a non-contact profilometer, and surface changes were inspected with SEM on selected sections. Data was normalised and underwent repeated measures MANOVA, accounting for substrate and erosive challenge as independent variables, with Bonferroni correction for significant post hoc interactions. RESULTS: After four cycles, polished samples had mean step heights of 3.08 (0.40) µm after erosion and 4.08 (0.37) µm after erosion/abrasion. For natural samples, these measurements were 1.52 (0.22) µm and 3.62 (0.39) µm, respectively. Natural surfaces displayed less wear than polished surfaces under erosion-only conditions (p<0.0001), but the difference disappeared with added abrasion. SEM revealed a shallow subsurface layer for polished surfaces and natural ones undergoing only erosion. However, natural surfaces exposed to both erosion and abrasion showed deeper subsurface changes up to 50 µm. CONCLUSION: Natural enamel, when exposed to erosion alone, showed less wear and minimal subsurface alterations. But with added abrasion, natural enamel surfaces saw increased wear and notable subsurface changes compared to polished ones. CLINICAL SIGNIFICANCE: The pronounced subsurface lesions observed on eroded/abraded natural enamel surfaces highlight how combined wear challenges may accelerate tooth tissue loss.

Avaliação do potencial erosivo de bebidas ácidas / Evaluation of the erosive potential of acid drinks

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Susceptibility of fluorotic enamel to dental erosion-abrasion.

Dental hard tissue conditions can be of pre- or post-eruptive nature, such as enamel fluorosis and erosive tooth wear (ETW), respectively. Dental enamel fluorosis is caused by the chronic and excessive intake of fluoride during enamel development, leading to increased fluoride concentration and increased porosity. ETW has become a common clinical condition and often impairs dental function and aesthetics. This in vitro study tested the hypothesis that fluorotic enamel presents different susceptibility to dental erosion-abrasion. It consisted of a 3×3×2 factorial design, considering a) fluorosis severity: sound (TF0), mild (TF1-2), moderate (TF3-4); b) abrasive challenge: low, medium, and high; and c) erosive challenge: yes or no. A total of 144 human teeth were selected according to the three fluorosis severity levels (n=48), and subdivided into six groups (n = 8) generated by the association of the different erosive and abrasive challenges. Enamel blocks (4×4 mm) were prepared from each tooth and their natural enamel surfaces subjected to an erosion-abrasion cycling model. After cycling, the depth of the lesions in enamel was assessed by profilometry. ANOVA showed that the three-way and two-way interactions among the factors were not significant (p > 0.20). Enamel fluorosis level (p=0.638) and abrasion level (p = 0.390) had no significant effect on lesion depth. Acid exposure caused significantly more enamel surface loss than water (p < 0.001). Considering the limitations of this in vitro study, fluorosis did not affect the susceptibility of enamel to dental erosion-abrasion.

Millennial drinks: acidity, fluoride content, and enamel softening.

This in vitro study aimed to evaluate the acidity and fluoride content of beverages commonly consumed by millennials and the enamel-softening effect of these drinks on tooth enamel. The study included 13 beverages in 4 categories: energy (sports) drink, flavored sparkling water, kombucha, and other (an unsweetened iced tea, a vegetable-fruit juice blend, and a soft drink). The acidity was measured with a pH/ion meter, and the fluoride concentration was measured with a combined fluoride electrode coupled to the meter (n = 10 measurements per beverage). The Vickers hardness number of extracted molars was measured before and after a 30-minute immersion in 4 representative beverages via 2 immersion protocols (n = 10 per beverage per protocol): (1) immersion in the beverage only and (2) immersion alternating between the beverage and artificial saliva every other minute. The pH and fluoride concentrations of the beverages ranged from 2.652 to 4.242 and from 0.0033 to 0.6045 ppm, respectively. One-way analysis of variance (ANOVA) revealed that all differences between beverages in pH values were statistically significant, as were the majority of differences in fluoride concentrations (P < 0.001). The beverages and the 2 immersion methods significantly affected enamel softening (2-way ANOVA, P = 0.0001 to 0.033). The representative energy drink (pH 2.990; 0.0102 ppm fluoride) caused the greatest enamel softening followed by the representative kombucha (pH 2.820; 0.2036 ppm fluoride). The representative flavored sparkling water (pH 4.066; 0.0098 ppm fluoride) caused significantly less enamel softening than the energy drink and kombucha. A root beer (pH 4.185; 0.6045 ppm fluoride) had the least enamel softening effect. All tested beverages were acidic and had a pH below 4.5; only some contained fluoride. Flavored sparkling water, likely due to its higher pH, caused less enamel softening than the tested energy drink and kombucha. The fluoride content of kombucha and root beer lower their enamel-softening effects. It is imperative that consumers be aware of the erosive potential of beverages they consume.

Damage from Carbonated Soft Drinks on Enamel: A Systematic Review.

The present study was conducted to analyze the erosive potential of the ever-increasing consumption of carbonated drinks on the dental surface. To identify relevant studies, a comprehensive search was conducted on PubMed, Scopus, and Web of Science covering the last 5 years (2018-2023) using the following Boolean keywords: "soft drinks AND tooth". Finally, a total of 19 studies were included. The initial search provided a total of 407 items. Nineteen records were finally involved in the inclusion phase, seven of which were in vivo and twelve in vitro. An abuse of carbonated acid substances leads to an increase in the possibility of dental erosion with consequent structural disintegration and reduction of the physical and mechanical properties of the enamel. There is thus greater bacterial adhesion on rougher surfaces, determined by the erosive process, and therefore a greater risk of caries. The pH of most commercialized carbonated drinks is lower than the critical pH for the demineralization of the enamel. Carbonated drinks' pH and duration of exposure have different deleterious effects on enamel.

The erosive effect of various drinks, foods, stimulants, medications and mouthwashes on human tooth enamel.

Two forms of non-carious dental disorder - erosive tooth hard tissue loss and dental erosion - have been increasingly observed in recent years. Dental erosion is the chemical loss of dental hard substances caused by exposure to acids not derived from oral bacteria. Mechanical forces from, for example, the tongue, the cheeks or toothbrushing, increase loss of partly-demineralized tooth surfaces and the cumulative loss of dental hard tissue is defined as erosive tooth wear (ETW). Dental hard tissue losses which occur because of very frequent acid exposure, such as through increased vomiting, but without mechanical stress, are also assigned to tooth erosion. Without prior softening, practically no loss of enamel takes place due to abrasion with the modern Western diet. The present work is a continuation of earlier work. A total of 226 beverages, food, stimulants as well as medicines and mouthwashes were tested for their erosive potential on premolars and deciduous molars covered with a human pellicle. The influence of temperature, phosphate and calcium was also investigated in additional experiments. The change in hardness before and after immersion in the respective test substance was measured and the erosive potential was classified. For each test product, we determined pH and other properties which were possibly related to erosive potential. There were considerable and sometimes surprising differences between the tested products. The addition of phosphate did not influence the erosive potential of the liquids, but calcium did. A modified erosion scheme is presented, which incorporates these and other new findings.

Erosive effects of commercially available alcoholic beverages on enamel.

This study aimed to investigate the effects of four alcoholic beverages on enamel erosion. Fifty enamel specimens were randomly allocated into the following five groups (n=10): group 1, water as negative control; group 2, red wine; group 3, white wine; group 4, distilled spirit; and group 5, beer. The specimens were immersed in the respective solution for a 16 h demineralization, followed by an 8 h remineralization in artificial saliva. Cyclic de- and re-mineralization were performed for 8 days. Surface roughness, microhardness and morphology of the enamel specimens were studied after the cycling. The results were analyzed by One-way ANOVA and Dunnett's post-hoc test (p<0.05). All investigated beverages showed an erosive effect on enamel. White wine had the highest erosive potential whereas distilled spirit had the least.

The in vitro Effect of Dentifrices With Activated Charcoal on Eroded Teeth.

AIM: The objective of this research was to compare the abrasive potential of dentifrices containing activated charcoal with those of a conventional dentifrice on the development of erosive tooth wear (ETW) in vitro. METHODS: Enamel and dentin samples were divided into toothpastes (n = 12): group (G)1-Colgate Triple Action (1450 ppm F) (positive control); G2-Colgate Natural Extracts (1450 ppm F); G3-Colgate Luminous White Activated Carbon (1450 ppm F); G4-Oral-B Whitening Therapy Charcoal (1100 ppm F); G5-Oral-B 3D White Mineral Clean (1100 ppm F); G6-Curaprox Black Is White (950 ppm F); and G7-erosion only (no abrasion, negative control). All samples were submitted to erosive pH cycles and G1 to G6 to abrasive challenges (15 seconds) using toothpastes' slurries plus 45 seconds of treatment for 7 days. The final profile was overlaid to the baseline one for the ETW calculation (µm). The data were subjected to analysis of variance/Tukey or Kruskal-Wallis/Dunn tests (P < .05). RESULTS: Oral-B 3D White (13.0 ± 1.0, 9.37 [1.36] µm), Oral-B Whitening Therapy (15.1 ± 1.2, 8.58 [1.71] µm), and Colgate Luminous White (13.6 ± 1.0, 7.46 [0.94] µm) toothpastes promoted the greatest enamel and dentin wear. On the other hand, Colgate Triple Action (12.2 ± 1.2, 5.30 [1.26] µm), Colgate Natural Extracts (10.8 ± 1.1, 4.16 [1.11] µm), and Curaprox Black Is White (11.5 ± 1.5, 4.06 [0.92] µm) toothpastes promoted lower wear values, similar to erosion only (4.16 [0.94] µm) in the case of dentin but not enamel (7.1 ± 0.8 µm). CONCLUSIONS: Toothpastes containing charcoal combined with pyrophosphate may have a high abrasive effect on eroded tooth surfaces. Many patients influenced by digital marketing use toothpastes containing activated charcoal with the aim of bleaching their teeth. However, care should be taken when using these products, as they may have a high abrasive effect.

Erosion-Driven Enamel Crystallite Growth Phenomenon at the Tooth Surface In Vitro.

The erosion of tooth enamel is a common oral disease. The erosion pattern and location and the effects of nanoscale chemical composition on the erosion susceptibility of enamel have been well documented. However, the enamel remineralization accompanied by erosion and its underlying physicochemical mechanisms still remain poorly understood. Here, using rat molars selected for its good relevancy to human teeth, we investigated the remineralization behavior of the outermost enamel surface at the nanoscale level during erosion in diluted hydrochloric acid solutions. While particles on the outermost enamel surface that represent the termination of crystallites protruding to the surface from the near-surface core eroded by acid-attack, the lateral-growth of the particles (i.e., the main remineralization picture of the surface enamel) occurred concurrently. Ionic analyses indicate that the particle growth is driven by the local increase in pH near the eroding enamel surface as a result of the combination of the PO43- and CO32- released from the enamel surface with H+. As the pH increases eventually to the equilibrium pH level (∼5.5), a local supersaturation of solute ions is induced, resulting in particle growth. A simple growth model based on the experimental results together with an assumption that the particle growth is a diffusional process suggests that the particle growth rate is controlled by the degree of supersaturation and accommodation site for solute ions, which are affected by the pH of solution eroding the enamel surface. The remineralization mechanism presented by our study can explain how the enamel on being acid-exposed or tooth decay progress by beverage or food can naturally remineralize in the oral cavity and how remineralization can foster different surface topology at the nanoscale, depending on the pH value of etchant before the dental filling material is applied.

Effect of air-abrasion pretreatment with three bioactive materials on enamel susceptibility to erosion by artificial gastric juice.

OBJECTIVE: The purpose of the study was to investigate the protective effect of three in-office preventive treatments with bioactive materials against enamel erosion induced by artificial gastric juice similar to that found in gastroesophageal reflux disease (GERD) patients. The treatments included air-abrasion of enamel with a fluoride-containing bioactive glass (BioMinF®), Bioglass 45S5 (ProSylc) and nano-hydroxyapatite (MI Pearls) to test enamel susceptibility following an erosive challenge. METHODS: Enamel surface loss was evaluated using confocal microscopy, while changes in enamel surface roughness and morphology were also investigated after the treatments. SEM and EDS were used to observe formation of apatite crystals on enamel and to detect alterations in mineral composition. In Group 1 (negative control) the specimens did not receive any treatment; Group 2 specimens (positive control) treated with 0.4 % SnF2, while in Groups 3-5 enamel was air-abraded with BioMinF®, ProSylc and MI Pearls, respectively. RESULTS: All the experimental groups reduced significantly enamel surface loss compared to the negative control group (p < 0.05), except for the MI Pearls treatment (p > 0.05). The most protective behavior against erosion presented the treatment with SnF2. BioMinF induced the larger amount of apatite crystals on the enamel surface, followed by ProSylc. SIGNIFICANCE: BioMinF and ProSylc treatments may be beneficial against dental erosion induced by gastric juice in GERD patients, while MI Pearls treatment may not suitable for this indication. Both materials promote formation of apatite crystals on enamel in acidic conditions protecting the surface from the erosion. The tested treatments may be useful in GERD patients who cannot comply with at-home therapies with SnF2.

Effect of pH and titratable acidity on enamel and dentine erosion.

OBJECTIVES: The relative effect of pH and titratable acidity on tooth erosion remains unclear. We determined the effect of both properties on in vivo salivary pH recovery and on enamel and dentine early erosion in situ. METHODS: Solutions simulating acidic beverages with different pHs (2.5 or 3.5) and titratable acidities (0, 25, or 100 mM citric acid) were tested. In an in vivo study (n = 20 participants), the salivary pH was determined before, during, and up to 2 min after exposure to the tested solutions. In situ, 12 participants exposed enamel and root dentine slabs to the tested solutions simulating a beverage consumption; early erosion was assessed by percentage of surface hardness loss (%SHL). Groups were compared by ANOVA (p < 0.05). RESULTS: Saliva pH was lower after exposure to solutions at pH 2.5, irrespective of titratable acidity; pH recovery took longer for solutions with higher titratable acidities, irrespective of their pHs. In situ, the highest %SHL was observed for the solution with lower pH and higher titratable acidities. The addition of citric acid increased the %SHL by 2.5-3 times in enamel, and at least 5 times in dentine. CONCLUSIONS: Both pH and titratable acidity may play a role on the erosive potential of acidic beverages. CLINICAL RELEVANCE: Acidic beverages with lower pHs promote erosion by an initial acid etching of the surface; those with a higher titratable acidity slow down the salivary pH recovery. Both properties contribute to the overall erosive potential.

The neutralizing effect of mouth rinsing with alkaline electrolyzed water on different regions of the oral cavity acidified by acidic beverages.

PURPOSE: Acids contained in foods and drinks are involved in the initiation and progression of dental erosion which causes tooth wear. The authors evaluated the neutralizing activity of alkaline electrolyzed water (AEW) in vitro and in vivo. METHODS: The neutralizing ability of AEW against eight beverages was investigated in vitro. Furthermore, in an in vivo study, the effect of mouth rinsing with AEW on the pH of the oral cavity acidified with acidic beverages was examined. Following mouth rinsing, the oral pH was measured using a pH meter with a micro pH-sensor at the cervical surface of the mandibular teeth and the surface of soft tissues. RESULTS: Regarding the neutralizing ability, the higher the pH of the AEW, the lower the volume required for neutralization of the tooth surface. Changes in the pH by mouth rinsing with AEW and purified tap water (PTW) were analyzed. The degree of increase of pH with AEW was greater than with PTW at almost all sites. CONCLUSION: These results suggest that AEW has the potential to prevent the initiation and progression of dental erosion. Mouth rinsing with AEW could be a simple and effective way to prevent the initiation and progression of dental erosion and dental caries.

Erosive potential of commonly available vapes: a cause for concern?

Objectives Relatively little is known about the erosive potential of vape products, an important consideration for dental health. This study analysed flavoured vapes with potentially low pH, including fruit and drink flavours.Methods The pH of 45 purposefully selected vapes was measured undiluted in triplicate. Serial dilution was conducted on the most erosive product to investigate if/when the erosive potential pH of 5.5 was reached. One of the most erosive samples was tested, undiluted and diluted, after four months of opening. Content analysis of the vape labels determined ingredients, place of manufacture, product usage instructions and health warnings.Results Eighty-four percent of undiluted vape samples had a pH below 5.5. Erosive potential was not predicted by the flavour, with orange and cola samples higher than anticipated (pH 3.56-6.23 and 5.04-5.63, respectively). Products that were predicted to be non-acidic such as vanilla showed considerable variation ranging from pH 4.69-5.63. Freshly opened or stored samples did not reach a non-erosive potential pH of 5.5 or above, even when diluted to represent concentrations used when vaped. Labels were not detailed enough to ascertain which ingredients were contributing to acidity or buffering capacity or to allow consumers to identify the least harmful products in terms of oral health.Conclusions Present labelling of commercially available vapes does not allow consumers to ascertain the erosive potential and possible dental damage that may be inflicted by their use. More effective labelling and/or health warnings are required to educate consumers and dental health professionals on these products.

The effect of 1,450 and 5,000 ppm sodium fluoride on polished dentin after citric acid erosion using change in step height.

PURPOSE: To measure step height change, using profilometry on dentin, after pre-treatment with sodium fluoride at 1,450 and 5,000 ppm and then erosion with citric acid. . METHODS: Dentin specimens (n= 150), sectioned from the coronal aspect of extracted human molars were randomly divided into three groups of 60 samples each and fully immersed in deionized water (control), or solutions of NaF with 1,450 ppm (F1450) or 5,000 ppm (F5000) for 3 minutes and then artificial saliva (not containing proteins) for 30 minutes. The samples were eroded for 10, 15, 20 or 25 minutes in 0.3% citric acid at pH 2.7. The mean step height change was calculated using confocal non-contact white light laser profilometry. . RESULTS: The mean (SD) step height for the control group at 25 minutes of acid exposure was 9.08 µm (± 0.74), for the F1450 fluoride group 8.74 µm (± 0.58) and for F5000 group 7.01 µm (± 0.56) µm, respectively. There were no statistically significant differences between the control group to the F1450 at any immersion times, whereas at F5000 there were statistically significant differences at all times (P< 0.0001). Within the limitations of this in vitro study, step height in dentin increased with time of exposure to citric acid and 5,000 ppm of sodium fluoride significantly reduced step height with artificial saliva. CLINICAL SIGNIFICANCE: 5,000 ppm NaF better protected dentin in an erosion model than concentrations commonly found in toothpastes.

Safety and In Situ Antierosive Effect of CaneCPI-5 on Dental Enamel.

The sugarcane cystatin (CaneCPI-5) was recently cloned and showed strong binding force to dental enamel and protection against initial erosion. However, evaluations on its safety and efficacy in a situation closer to the clinical condition are necessary. In the present study we analyzed 1) the cytotoxicity of CaneCPI-5 on human gingival fibroblasts (HGFs); 2) the ability of CaneCPI-5 to reduce enamel erosion and erosion+abrasion in situ. In part 1, HGFs were treated with CaneCPI-5 (0.025, 0.05, 0.1, 0.5 or 1.0 mg/mL) or no treatment (control). The cytotoxicity was assessed after 60 s and 24 h by mitochondrial activity (MTT), confocal microscopy, and hematoxylin/eosin staining. In part 2, 15 volunteers participated in a double-blind crossover protocol consisting of 3 phases, according to the following treatments: 1) 0.1 mg/mL CaneCPI-5; 2) SnCl2/NaF/AmF (Elmex; positive control); 3) water (negative control). The volunteers wore an appliance containing 4 bovine enamel specimens for 5 d. Each day, the specimens were individually treated with 50 µL of the tested solutions per 60 s and then subjected to erosive challenges (0.1% citric acid, pH 2.5, for 90 s, 4 times per day). After the first and last erosive challenge each day, 2 samples were abraded (toothbrushing, 15 s). Enamel wear was measured by contact profilometry. One or two-way analysis of variance (ANOVA)/Tukey's or Sidak's tests (P < 0.05) were applied. Regardless of the concentration and the experimental time, CaneCPI-5 did not decrease the cell viability compared to the negative control (P < 0.05). Erosion+abrasion led to significantly greater wear compared to erosion only. For both conditions, the lowest wear was found for SnCl2 and CaneCPI-5, which did not differ significantly from each other, but showed significant protection when compared to the negative control. In conclusion, CaneCPI-5 is safe on HGFs and reduces enamel erosive wear to the same extent as a commercial solution used to control erosive tooth wear (ETW).

Effect of Acid Beverage on the Microhardness of Primary Tooth Enamel In Vitro.

Purpose: To assess the effects of a soft drink, a soybean-based apple juice and strawberry juice on the superficial and deep microhardness of primary tooth enamel.
Methods: Sixty primary teeth were divided according to the beverages and a control group (artificial saliva). Immersion cycles were carried out under agitation (five minutes three times a day over 60 days). Superficial microhardness measurements were taken after seven, 15, 30, 45, and 60 days. Teeth were cut for deep microhardness evaluation. Analysis of variance and Tukey's test (95 percent confidence interval) were used for data analysis. Teeth were scanned by electron microscopy for quantitative analysis.
Results: The soybean drink led to a significant decrease in the superficial microhardness ( P <0.05) at all tested times. The decrease for the strawberry juice was steeper than for the soybean drink and the soft drink significantly decreased the superficial microhardness at all times. The soybean drink recorded lower surface deep microhardness values while the juice presented similar results to the soybean drink at a depth of up to 200 µm. There was a gradual and statistically significant increase at a depth of up to 300 µm with the soft drink. Scanning electron microscopy evaluation showed that all beverages had gradual demineralization, being evident on the 60th day; the soft drink showed the greatest overall loss of enamel.
Conclusion: All beverages affected the microhardness of primary teeth enamel. The soft drink was the most harmful to enamel among the assessed beverages.

Erosive Potential of Bottled Salad Dressings.

PURPOSE: A previous clinical study showed that the prevalence of erosive toothwear in vegetarians is statistically significantly higher than in nonvegetarians, due to the consumption of vinegar and other acidic foodstuffs. To adequately inform patients, this study investigated the erosive potential of bottled salad dressings available in Switzerland and compared it with that of orange juice. Materials and Methods: One hundred enamel samples of bovine teeth were divided into ten groups. Samples were placed in 1 of 9 bottled salad dressings or orange juice (Granini) for 2 min. Afterwards, they were rinsed with Zürich tap water for 30 s, followed by abrasion with a toothbrush for 20 brush strokes and a toothpaste-saliva mixture. Erosive/abrasive enamel wear was determined with contact profilometry after 40 cycles. Results: The enamel wear (median/IQR) caused by Tradition Sauce Balsamique (9.5 µm/5.3 µm), M-Classic Dressing Italiano (10.9 µm/12.3 µm), Betty Bossi Balsamico Dressing (9.4 µm/4.5 µm) and Thomy Balsamico Vinaigrette Dressing (14.2 µm/6.5 µm) was statistically significantly higher than that caused by orange juice (2.4 µm/0.8 µm). Enamel wear caused by M-Classic Dressing French Joghurt (0.2 µm/0.2 µm) and Coop Qualité & Prix French Dressing (1.2 µm/1.0 µm) was statistically significantly lower compared to that of orange juice. Conclusions: The pure balsamico vinegar-based dressings (Italian type) showed a statistically significantly higher erosive potential than orange juice, whereas dressings containing calcium-rich products (enriched with milk and/or cream) (French-type) caused lower enamel wear than orange juice. The study shows that some bottled dressings have erosive potential even higher than orange juice and patients should be informed accordingly.