In Vitro assessment of dentin erosion after immersion in acidic beverages: surface profile analysis and energy-dispersive X-ray fluorescence spectrometry study

Energy drinks alter the surface morphology and roughness of composites, fissure sealants and titanium: An in vitro study

Objectives

The influence of energy drinks on dental materials are relatively under addressed. Our aim was to investigate the effect of energy drinks on dental materials used intraorally in young individuals. Commonly used preventive, restorative, and orthodontic materials were tested in vitro.

Methods

The effect of two commercially available energy drinks (HELL, BURN) was investigated on different dental materials: machined, anodized Titanium (grade 5: Ti6Al4V) and composites (Grandio Seal, VOCO; Filtek Z250, 3M ESPE; Estelite SQ, TOKUYAMA). The roughness (Ra) and morphological changes were examined by atomic force microscopy (AFM) and scanning electron microscopy (SEM).

Results

AFM and SEM revealed significant differences in the Ra and morphology of the samples. AFM results for the machined and anodized titanium samples showed that the two energy drinks modified the surface roughness differently; BURN changed the roughness of machined samples significantly, while anodized discs were not altered significantly by the two energy drinks. In case of composite samples there was no significant difference for the Estelite SQ, relative low differences for the Filtek Z250 and significant changes in the morphology and surface roughness of Grandio Seal.

Significance

On all tested materials, changes in the surface roughness and morphology were more or less detected, proving energy drinks do in fact have a harmful effect. It can be concluded that material erosion depends on the material composition and particle arrangement. Where the surface is characterized by a regular, uniform particle arrangement, energy drinks are less able to influence the roughness, while for samples where the surface is rich in aggregates, the material erodes the surface much more easily.

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Consumption of energy drinks is increasing amongst children and young individuals.

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Preventive, restorative, and orthodontic materials used in young individuals are affected by energy drinks.

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Roughness and morphological change of dental materials is observed in case of Hell and Burn impact.

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Burn damages more titanium, fissure sealant and composite materials.

In vitro comparison of the erosive potential of four different wines on human dental enamel

Background/Aim: This study aimed to investigate the erosive potential of wines derived from Anatolia on human teeth in vitro. Material and Methods: In this study two red (Öküzgözü, Boğazkere) and two white (Sultaniye, Narince) wines, citric acid and distilled water were used to investigate erosive effects. The pH, titratable acidity, iron and calcium ion levels of the groups were measured. Each group included 10 specimen and they were exposed to 25 ml of wine sample for 5 seconds, artificial saliva for 10 seconds for 10 times. The initial and the final phosphate concentrations were measured by the UV spectrophotometer and the difference between the measurements was calculated. One sample was examined under a scanning electron microscope and the data were analyzed statistically using One-way ANOVA and Pearson correlation test. Results: Mineral loss and erosive lesion depth values were ranged from highest to the lowest Sultaniye, Boğazkere, Öküzgözü and Narince, respectively. Correlation between mineral loss and pH was statistically significant (p<0.01). However, there was no correlation between the iron and calcium ion level and mineral loss. Conclusions: All the investigated wines have pH values below the critical value for enamel dissolution while Sultaniye was significantly more erosive than the others. There is a negative correlation between pH and erosive potential of the wine. Within the limits of this in vitro study, it can be expected that a regular consumption of wines might cause dental erosion.

ToF-SIMS Analysis of Demineralized Dentin Biomodified with Calcium Phosphate and Collagen Crosslinking: Effect on Marginal Adaptation of Class V Adhesive Restorations

This study aimed to assess the effect of biomodification before adhesive procedures on the tooth-restoration interface of class V restorations located in caries-simulated vs. sound dentin, and the quality of dentin surface by time-of-flight secondary ion mass spectrometry (ToF-SIMS). Class V cavities located on cervical dentin were prepared on the buccal surfaces of extracted human molars under the simulation of intratubular fluid flow. Two dentin types, i.e., sound and demineralized by formic-acid, were biomodified with 1% riboflavin and calcium phosphate (CaP) prior to the application of a universal adhesive (Clearfil Universal Bond) in etch and rinse or self-etch mode, and a conventional micro hybrid composite (Clearfil APX). Restorations were subjected to thermo mechanical fatigue test and percentages of continuous margins (% CM) before/after fatigue were compared. Bio modification of dentin surfaces at the molecular level was analyzed by Time-of-Flight Secondary Mass Spectometry (ToF-SIMS). % CM were still significantly higher in tooth-restoration interfaces on sound dentin. Meanwhile, biomodification with riboflavin and CaP had no detrimental effect on adhesion and in carious dentin, it improved the % CM both before and after loading. Etching carious dentin with phosphoric acid provided with the lowest results, leading even to restoration loss. The presence of molecule fragments of riboflavin and CaP were detected by ToF-SIMS, evidencing dentin biomodification. The adhesive interface involving carious dentin could be improved by the use of a collagen crosslinker and CaP prior to adhesive procedures.

Effect of acidic beverages on surface roughness and color stability of artificial teeth and acrylic resin

PURPOSE

The aim was to evaluate the effect of four acidic beverages on the roughness (Ra) and color change (ΔE_ab) of two brands of artificial teeth and a heat-polymerized acrylic resin (HPAR) for use in a prosthetic base.

MATERIALS AND METHODS

All materials were divided into 5 groups, according to the used acidic beverage (artificial saliva - control, red wine, orange juice, coke-based, and lemon juice-based soft drink). The immersion process was divided into two stages: T1 - immersion in the acidic solutions for 10 minutes for 14 days; T2 - after T1, the samples were immersed in grape juice for 14 days. The Ra of the samples was evaluated in a rugosimeter and the ΔE_ab in a spectrophotometer, before and after the immersions. The analysis of variance of one (ΔE_ab) and two factors (Ra) and Tukey were performed (α=.05).

RESULTS

There was a statistical difference for roughness after immersion (T1) for Trilux and Tritone teeth, regardless of the acid solution. For Trilux teeth, all acid solutions increased Ra (P<.05). For Tritone teeth, only the coke-based soft drink did not statistically change Ra. Grape juice (T2) altered Ra only of artificial teeth (P<.05). The color was changed for all materials, after T1 and T2.

CONCLUSION

In general, the acidic solutions changed the Ra and ΔE_ab of HPAR and artificial teeth after T1. The grape juice altered the roughness only of the artificial teeth, promoting a clinically acceptable color change in the materials.

Glass Fiber Reinforced Composite Orthodontic Retainer: In Vitro Effect of Tooth Brushing on the Surface Wear and Mechanical Properties

Fiber reinforced composites (FRCs) are metal free materials that have many applications in dentistry. In clinical orthodontics, they are used as retainers after active treatment in order to avoid relapse. However, although the modulus of the elasticity of FRCs is low, the rigidity of the material in the form of a relatively thick retainer with a surface cover of a flowable resin composite is known to have higher structural rigidity than stainless steel splints. The aim of the present study is to measure load and bending stress of stainless steel wires, as well as flowable resin composite covered and spot-bonded FRC retainer materials after tooth brushing. These materials were tested with a three point bending test for three different conditions: no brushing, 26 min of brushing, and 60 min of brushing. SEM images were taken before and after different times of tooth brushing. Results showed that stainless steel was not significantly affected by tooth brushing. On the other hand, a significant reduction of values at maximum load at fracture was reported for both FRC groups, and uncovered FRCs were most affected. Concerning maximum bending stress, no significant reduction by pretreatment conditions was reported for the materials tested. SEM images showed no evident wear for stainless steel. Flowable resin composite covered FRCs showed some signs of composite wear, whereas spot-bonded FRCs, i.e., without the surface cover of a flowable resin composite, showed signs of wear on the FRC and exposed glass fibers from the FRC’s polymer matrix. Because of the significant changes of the reduction of maximum load values and the wear for spot-bonded FRCs, this technique needs further in vitro and in vivo tests before it can be performed routinely in clinical practice.

Ultrastructural changes in the cemento-enamel junction caused by acidic beverages: An in vitro study

The present in vitro study was aimed at evaluating the morphological changes in the cemento-enamel junction (CEJ) after exposure to acidic beverages using the scanning electron microscopy (SEM). The initial pH and titratable acidity (TA) was analyzed from follow groups: (I) Coca cola, (II) orange juice, (III) Cedevita, (IV) Red Bull, (V) Somersby cider, and (VI) white wine. The CEJ samples (n = 64), obtained from unerupted third molars, were allocated to one control (artificial saliva, n = 16) and six experimental groups (n = 8). The experimental samples were immersed in beverages (50 ml) for 15 min, three times daily, 10 days, and in artificial saliva between immersions. SEM analysis was performed in a blind manner, according to scoring scale. One-way ANOVA and Tukey's post hoc tests, as well as Kruskal-Wallis and Mann-Whitney U test used for statistical analysis. The pH values of the acidic beverages ranged from 2.65 (Coca cola) to 3.73 (orange juice), and TA ranged from 1.90 ml (Coca cola) to 5.70 ml (orange juice) of NaOH to reach pH 7.0. The SEM analysis indicated statistically significant differences between the control samples and those immersed in acidic beverages. The Groups IV, I, and II, showed the highest CEJ damage grade while those of the Group VI were the lowest. All the tested acidic beverages caused morphological changes in the CEJ with a smaller or larger exposure of dentine surface, and were not always related to the pH or TA of acidic beverages.

An In Situ Evaluation of the Protective Effect of Nano Eggshell/Titanium Dioxide against Erosive Acids

OBJECTIVES

Enamel erosion caused by high consumption of acidic drinks poses a significant public health concern. This study was aimed to determine the protective effect of eggshell-titanium dioxide composite (EB@TiO2) against erosive acids on tooth enamel.

METHODS

Twenty prepared bovine tooth enamel specimens were randomly assigned to 5 sample groups (n=4): (1) unexposed tooth enamel; (2) exposed tooth enamel + HCI; (3) exposed tooth enamel + HCI + Colgate toothpaste; (4) exposed tooth enamel + HCI + Sensodyne toothpaste; and (5) exposed tooth enamel + HCI + EB@TiO2. The mean roughness value (R rms) of the exposed and unexposed tooth was measured with atomic force microscope (AFM). Scanning electron microscope (SEM) and Raman spectroscopy techniques were used to evaluate the surface morphology and changes. ANOVA was used to analyze the mean square roughness (R rms) values for all specimens. Bonferonni correction was used to identify the mean differences among the 5 groups (α=0.05). The R rms values measured for the unexposed and exposed specimens in HCI alone were statistically significant (P < 0.05).

RESULTS

No significant differences were found for the unexposed and exposed specimens in HCI + toothpaste and EB@TiO2. The tooth enamel specimens exposed to HCI + Sensodyne had the highest R rms values, while specimens exposed to HCI + EB@TiO2 had the lowest R rms values.

CONCLUSIONS

This study confirms that the investigated toothpaste provides protection against acidic substances. The study results further suggests that EB@TiO2 could be used to provide enhanced protection for tooth enamel.

Analysis of the bond interface between self-adhesive resin cement to eroded dentin in vitro

The purpose of this study was to evaluate the bonding interface between a self-adhesive resin cement to in vitro eroded dentin. Seventy-two third molars were used and divided into two groups: sound dentin and in vitro eroded dentin. The in vitro erosion was performed following a demineralization protocol, in which the specimens were immersed in a demineralizing solution for 2 minutes per cycle and remineralizing solution for 10 minutes per cycle for 9 days. Both groups were submitted to four dentin surface treatments: control group (without any treatment), 2% chlorhexidine, 20% polyacrylic acid, and 0.1 M EDTA (n = 9). Blocks of resin-based composite were bonded with RelyX U200 self-adhesive resin cement applied on the pretreated dentin surfaces. The teeth were sectioned into beams (1mm²) and submitted to microtensile bond strength testing to evaluate the bond strength of self-adhesive resin cement to dentin after 24 hours and 8 months of immersion in artificial saliva. Three specimens of each group were longitudinally cut and evaluated using confocal laser scanning microscopy to analyze the dentin/cement interface. Eroded dentin showed higher bond strength values when compared to sound dentin for the 2% chlorhexidine group (p = 0.03), 24 hours after adhesion. When considering eroded dentin, the 0.1M EDTA group showed higher bond strength values with a statistically significant difference only for the control group (p = 0.002). After 8 months of storage, the present results showed that there was no statistically significant difference between the two substrates for all experimental groups (p>0.05). Analysis of the microscopy confocal showed different types of treatments performed on dentin generally increased tags formation when compared to the control group. The eroded dentin showed a significant increase in density and depth of resinous tags when compared to sound dentin. The storage of samples for 8 months seems to have not caused significant degradation of the adhesive interface.

In vitro effect of energy drinks on human enamel surface

Abstract Introduction Energy drinks (ED) possess low pH and citric acid in their composition, making them potentially erosive beverages that can contribute to the high dental erosion rates found currently in the general population and also in young people. Objective To evaluate the mean pH and titratable acidity of commercial ED and the influence of a brand of ED on the superficial microhardness of human enamel. Material and method Ten commercial ED were selected and the pH of two lots of each ED with and without gas was obtained. Acid titration was conducted with the addition of NaOH aliquots until the pH 7 was reached. Eighteen human enamel specimens were allocated in three groups (N=6), Red Bull (RB), Red Bull Light (RBL) and distilled water (C), submitted to an acid challenge with the ED, six consecutive times, with 12 hours intervals, during three days. Knoop microhardness was measured before and after the acid challenge. Result All ED brands tested presented low pH levels ranging from 2.1 to 3.2. Regarding titratable acidity, it was found that the amount of base required promoting the neutralization of the solutions ranged from 1200μL to 3750μL. Samples of human enamel in the RB and RBL groups submitted to the acid challenge presented significantly decreased Knoop microhardness when compared with the group C. Conclusion All ED examined have potential to promote mineral loss due to the low pH and high titratable acidity. The ED analyzed promoted significant mineral losses on the dental enamel surface.

Do Dietary Habits Influence Trace Elements Release from Fixed Orthodontic Appliances?

The objective was to investigate the effect of dietary habits on the release of Cr and Ni ions from orthodontic appliances by hair mineral analysis. Patients (N = 47) underwent electronic questionnaire survey to investigate the effect of dietary habits on Cr and Ni levels in hair. The research was carried out on hair sampled at the beginning and in the 4th, 8th, and 12th months of the treatment. The content of Cr and Ni in the collected samples was determined by ICP-OES. The study showed that consumption of acidic dietary products may have the effect on increasing the release of Cr and Ni ions from orthodontic appliances. The release of Cr from orthodontic appliances in patients who consumed fruit juice, coffee, yoghurt, and vinegar was higher. The coefficients enabling comparison of metal ions release pattern at a given sampling points were defined. The comparison of the coefficients yielded the information on the possible magnification of metal ions released as the result of the additional factor consumption of acidic food or drink that intensifies metal ions release. The following magnification pattern was found for chromium: coffee (7.57 times) > yoghurt (2.53) > juice (1.86) > vinegar (1.08), and for nickel: vinegar (2.2) > coffee (1.22) > juice (1.05). Yoghurt did not intensify the release of nickel. Concluding, orthodontic patients should avoid drinking/eating coffee, yoghurt, fruit juices, and vinegar.

Harmful Effect of Beer on Bovine Enamel Microhardness - In Vitro Study

This study aimed to evaluate the effect of beers on the bovine enamel microhardness. Fifty rectangular (1 x 3 x 1 mm–height x width x thickness) enamel specimens were obtained from permanent bovine incisors, and divided into five groups (n = 10) according to the treatment employed: Saliva, Coke, Brahma, Heineken, and Budweiser. Microhardness (Knoop) were obtained before; after 5, 30 and 60 min of immersion in each solution. The data were analyzed using repeated two-way ANOVA and Tukey´s test (p<0.05). Coke decreased the microhardness in all immersion times, and Heineken, showed low values after 60 minutes. Beers tested have low potential to cause enamel erosion when compared to Coke.

Effect of Fluoride Varnish Combined with Er:YAG Laser on the Permeability of Eroded Dentin: An In Situ Study

This study evaluated the combined effect of fluoride varnish and Er:YAG laser on the permeability of eroded bovine root dentin. After initial erosive challenge followed by a remineralization period, the specimens were divided in two groups according to the treatment - fluoride varnish and non-fluoride varnish - and were subdivided according to the irradiation protocol: Er:YAG laser (100 mJ, 3 Hz, 12.8 J/cm2per pulse, non-contact and defocus mode) and non-irradiated. After a lead-in period, 7 volunteers wore a palatal device containing 4 specimens that were subjected to erosive challenges. At the first experimental phase, 4 volunteers used specimens treated with fluoride varnish and fluoride varnish+Er:YAG laser and 3 volunteers used specimens treated with non-fluoride varnish and non-fluoride varnish+Er:YAG laser. After a washout period, volunteers were crossed to treatments, characterizing a 2x2 crossover experiment. At the end of the experimental phase, the quantitative response variable was obtained by permeability analysis and the qualitative response by scanning electron microscopy (SEM). Two-way ANOVA and Tukey-Kramer's test revealed that specimens treated with fluoride varnish+Er:YAG laser showed the lowest permeability and a significant difference was found between this group and the others. When varnish (fluoride/non-fluoride) was applied in the absence of Er:YAG laser, higher permeability was found when compared to the laser-treated groups. SEM evaluations showed partially or completely obliterated dentinal tubules when specimens were treated with fluoride varnish+Er:YAG laser. It may be concluded that Er:YAG laser was able to control the permeability of eroded root dentin and the combination with fluoride varnish increased laser action.

Analysis of Dental Enamel Surface Submitted to Fruit Juice Plus Soymilk by Micro X-Ray Fluorescence: In Vitro Study

OBJECTIVE

This paper aimed to analyze the in vitro industrialized fruit juices effect plus soy to establish the erosive potential of these solutions.

MATERIALS AND METHODS

Seventy bovine incisors were selected after being evaluated under stereomicroscope. Their crowns were prepared and randomly divided into 7 groups, using microhardness with allocation criteria. The crowns were submitted to the fruit juice plus soy during 15 days, twice a day. The pH values, acid titration, and Knoop microhardness were recorded and the specimens were evaluated using X-ray microfluorescence (µXRF).

RESULTS

The pH average for all juices and after 3 days was significantly below the critical value for dental erosion. In average, the pH value decreases 14% comparing initial time and pH after 3 days. Comparing before and after, there was a 49% microhardness decrease measured in groups (p < 0.05). Groups G1, G2, G5, and G6 are above this average. The analysis by μXRF showed a decrease of approximately 7% Ca and 4% P on bovine crowns surface. Florida (FL) statistical analysis showed a statistically significant 1 difference between groups. Thus, a tooth chance to suffer demineralization due to industrialized fruit juices plus soy is real.

Susceptibility of restorations and adjacent enamel/dentine to erosion under different salivary flow conditions

OBJECTIVES

The aim of this study was to investigate the effect of erosion on direct tooth-coloured restorations and adjacent enamel/dentine under low and normal simulated salivary flow rates.

METHODS

Bovine enamel and dentine specimens were prepared (n=16) and restored with the following materials: resin composite (FiltekZ250), resin-modified glass ionomer cement (Fuji II LC), high-viscosity glass ionomer cement (Fuji IX), and conventional glass ionomer cement (Fuji II). They were submitted to in vitro erosion-remineralisation cycling simulating normal (0.5 ml/min) and low (0.05 ml/min) salivary flow rates, for 5 days. The restorative material, enamel and dentine substrates were assessed with optical profilometry for surface loss. Mixed-model ANOVAs were used for statistical comparisons (alpha=0.05).

RESULTS

Low-salivary flow significantly increased surface loss for all tested substrates (p<0.05), except FiltekZ250. Surface loss (mean±SD, in micrometres) under low-salivary flow was significantly higher in enamel (19.75±4.27) and dentine (23.08±3.48) adjacent to FiltekZ250 compared to Fuji II LC (16.33±2.30 and 20.47±2.58, respectively) and Fuji IX (15.79±2.41 and 20.63±2.34, respectively). Restoration surface degradation was significantly lower for Fuji II LC (2.17±0.73) than for both Fuji II (13.03±6.79), and Fuji IX (16.74±7.72) under low-salivary flow condition; whereas FiltekZ250 exhibited no meaningful surface loss (-0.35±0.19).

CONCLUSION

Limited to these in vitro conditions, low-salivary flow promoted higher erosive conditions for teeth and restorations. Some fluoride-containing restorative materials may reduce erosive wear on adjacent enamel and dentine. FiltekZ250 resisted erosive surface loss. Fuji II LC showed both reduced acid degradation and protection of adjacent dental surfaces to erosion.

CLINICAL SIGNIFICANCE

Patients at risk for erosion and in need of restorations may benefit from fluoride-containing restorative materials that resist erosive degradation. The data of this study suggest that resin-modified glass ionomer may be a suitable restoration for patients at higher risk of erosion with low exposure to fluoride.

Supplementation of an orange juice with dietary proteins to prevent enamel and dentin erosion

Protein supplementation may be an alternative to reduce the erosive potential of acidic drinks. The aim of this in vitro study was to evaluate the erosive potential of an orange juice modified by dietary proteins. A commercially available orange juice was added 0.2 g/L casein, 2.0 g/L ovalbumin and their combination. The juice with no additives and a commercially available calcium-modified juice were used as negative and positive controls, respectively. Human enamel and dentin specimens (n=11) were tested in an erosion-remineralization cycling model. Enamel was analyzed by surface microhardness and profilometry, whilst dentin by profilometry only. Statistical analyses were performed using one-way ANOVA followed by Tukey's test (p<0.05). Calcium-modified juice showed the lowest erosive potential for both analyses (p<0.05). For enamel, the protein-added groups did not differ from each other (p>0.05) and showed significantly lower enamel loss compared to negative control (p<0.05). Regarding surface microhardness, casein showed the highest values compared to negative control (p<0.05). For dentin, none of the protein-added groups showed lower values of surface loss compared to negative control (p>0.05). In conclusion, for enamel the protein-modified orange juices presented reduced erosion of enamel, with casein showing a trend for better protection. For dentin, no reduction in the erosive potential was observed for the tested protein-modified orange juices.

Nanoscratch testing for the assessment of enamel demineralization under conditions simulating wine erosion

BACKGROUND

Erosive tooth wear and dentinal hypersensitivity are common problems affecting professional wine tasters. By using nanoscratch testing, the aim of this in vitro study was to assess enamel softening under conditions simulating 10 one-minute episodes of wine erosion.

METHODS

Ten enamel specimens were bathed in artificial saliva for 2 hours before being eroded for 10 episodes, with each episode comprising one minute of wine erosion followed by one minute of remineralization in artificial saliva. Nanoscratches were placed with a spherical tip (20 μm radius) in a nanoindenter under a load of 100 mN at baseline (stage 1), after a one-erosion episode (stage 2) and after 10-erosion episodes (stage 3).

RESULTS

There were significant effects of erosion stages on both scratch depth (p<0.001) and surface roughness (p<0.001). Post hoc tests showed significant differences in both scratch depths and surface roughness between stages 1 and 3 (p<0.001), and between stages 2 and 3 (p<0.01).

CONCLUSIONS

Enamel softening occurs at an early stage of wine tasting, emphasizing the need to implement early preventive strategies in professional wine tasters. Further research elucidating the fundamental mechanisms involved in early stages of erosion has the potential to lead to development of more effective preventive strategies.