Bisphenol A Release from Orthodontic Clear Aligners: An In-Vitro Study

Bisphenol A (BPA) is a widely used synthetic compound that has been identified as an endocrine disruptor. It has been linked to adverse health effects such as developmental defects, infertility in both men and women, cardiovascular disease, and obesity. There has been increased interest in BPA’s effects on the developing fetus and data has revealed that doses below the presumed safe dose can produce harmful effects. Orthodontic clear aligner therapy is a popular treatment modality that involves the patient wearing sets of plastic aligners up to 22 hours per day for the duration of treatment. The BPA release from these aligners was rarely investigated. The objective of this study was to detect, quantify, and compare the amount of BPA released by 3 popular brands of orthodontic aligners in artificial saliva, artificial gastric fluid, and ethanol. Equal amounts of SmileDirectClub®, Invisalign®, and Essix Ace® aligners were placed in sterile glass vials and submerged in 5.5mL artificial saliva, artificial gastric fluid, and ethanol. Samples were incubated at 37°C and 1 mL aliquots were removed at various time points. Samples were prepared and analyzed using high performance liquid chromatography tandem mass spectrometry. BPA was released from all three brands of aligners with great variability. Peak BPA concentrations were detected in artificial saliva; Smile Direct Club® produced 5.0 ng/mL after 20 days, Invisalign® released 3.5ng/mL after 24 hours, and Essix Ace® released 6.3ng/mL after 10 days of incubation in artificial saliva. There was no significant difference in BPA concentration between the 3 types of aligners in the 3 media. When comparing time points, there was a significant increase of BPA release in the first 24 hours after incubation compared to the baseline (p<0.001). There is potential BPA release from orthodontic aligners. There was no significant difference in the amount of BPA released between the three types of aligners at any time point. The majority of BPA release occurred during the first 24 hours.

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Migration of fluoride ions from the permanent teeth into saliva in children with glass ionomer cement restorations: An in vitro study

Vojnosanitetski pregled ◽

10.2298/vsp1303279a ◽

2013 ◽

Vol 70 (3) ◽

pp. 279-283

Author(s):

Mirjana Apostolovic ◽

Biljana Kalicanin ◽

Marija Igic ◽

Olivera Trickovic-Janjic ◽

Dusan Surdilovic ◽

...

Keyword(s):

Artificial Saliva ◽

Fluorine Content ◽

In Vitro Study ◽

Vitro Study ◽

Permanent Teeth ◽

Glass Ionomer ◽

Fluoride Solution ◽

Low Concentration ◽

Significant Difference

Bacground/Aim. Glass ionomer cements (GIC) belong to the group of polycarboxyl cements, and one of the principal characteristics of these materials is their anticariogenic potential of fluorine release into saliva and enamel-dentin substance. The aim of this study was to examine the content of released fluorine from GIC restorations (Fuji IX, GC, Japan) of young permanent teeth in the medium of artificial saliva and similar releases in the same medium by the restorations of these teeth treated with a low concentration fluoride solution. Methods. We examined 12 premolars exctracted from orthodontic reasons. The GIC restored teeth were divided into the group treated daily with low concentration fluoride solution (334 ppm) and the control, not treated group. The samples of artificial saliva were analyzed for fluorine ion content using an ion selective electrode. Results. Our comparative analysis of the mean values using the Student?s t-test demonstrated a statistically significant difference in fluorine ion concentration in artificial saliva of fluoridated and non-fluoridated teeth with GIC fillings after 14 and 21 days (p < 0.05), while the difference detected after 7 days was with no statistical significance. Conclusion. The results of this in vitro study indicated that low-concentration fluoride solutions could serve to refluoridate GIC fillings and contribute to an increased fluorine content in saliva. The process of refluoridation of GIC fillings should be advised 2-3 weeks after the restoration, since the release of fluorine from GIC fillings diminishes in time.

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Effects of a bleaching agent with calcium on bovine enamel

European Journal of Dentistry ◽

10.4103/1305-7456.137634 ◽

2014 ◽

Vol 08 (03) ◽

pp. 320-325 ◽

Cited By ~ 9

Author(s):

Larissa Alexandrino ◽

Yasmin Gomes ◽

Eliane Alves ◽

Hilton Costi ◽

Hervé Rogez ◽

...

Keyword(s):

Artificial Saliva ◽

In Vitro Study ◽

Negative Control ◽

Double Blind ◽

Tristimulus Colorimetry ◽

Mean Values ◽

Significant Difference ◽

Bovine Enamel ◽

Bleaching Treatment

ABSTRACT Objective: This in vitro study analyzed the effects of a bleaching treatment containing 35% hydrogen peroxide (HP) with or without calcium on bovine enamel, using the Knoop hardness number (KHN), tristimulus colorimetry (TC), and scanning electron microscopy. Materials and Methods: Forty-five specimens were randomly divided into groups (n = 5), which included artificial saliva (negative control [NC]), 35% HP (positive control [PC]), and 35% HP Blue Calcium (HP Blue). The specimens were subjected to three bleaching sessions. During the sessions, the specimens were immersed in artificial saliva at 37°C. Before and after bleaching, KHN tests were conducted using a force of 25 gf for 5 s. TC was performed using the CIE-L*a*b* system and readouts were obtained at the following 4 time points: Before the bleaching treatment; after the first session, the second session, and the third session. The specimens were dehydrated and coated with gold, and the photomicrographs were analyzed in a double-blind manner with a LEO microscope. Results: Using one-way analysis of variance and Tukey's test (P < 0.05), a statistically significant difference was identified between the initial and final mean KHNs of the NC and PC groups, while the initial and final mean KHNs were not significantly different in the HP Blue group. The final mean values of ⋄E, ⋄L, and ⋄b of the PC and HP Blue groups were significantly higher than the initial values (P < 0.01 for both). The photomicrographs revealed no differences among the groups. Conclusions: Therefore, treatment with HP Blue prevented changes in the KHN without reducing the efficacy of bleaching.

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Tensile Strength of Novel Nonabsorbable PTFE (Teflon®) versus Other Suture Materials: An In Vitro Study

International Journal of Dentistry ◽

10.1155/2019/7419708 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5

Author(s):

José Arce ◽

Alondra Palacios ◽

Daniel Alvítez-Temoche ◽

G. Mendoza-Azpur ◽

Percy Romero-Tapia ◽

...

Keyword(s):

Tensile Strength ◽

Immersion Time ◽

Artificial Saliva ◽

In Vitro Study ◽

Test Machine ◽

Suture Materials ◽

Polyglactin 910 ◽

Significant Difference ◽

Failure Point

Objective. To compare the in vitro tensile strength of sutures used in implant surgery according to the type of thread and the immersion time in artificial saliva. Methods. For the development of the study, three suture materials were used: polyglactin 910 (PG), black silk (BS), and Teflon (PTFE) 4-0; 150 samples were used, which were divided among each type of suture and then subdivided into five groups of 10 according to the various immersion times (baseline, 3, 7, 14, and 21 days) in artificial saliva. A universal test machine was used to measure the tensile strength at a speed of 25 cm/min, stretch each sample until the material fails, and record the maximum strength in Newtons (N). Finally, the failure point of the samples was evaluated at 10× increase using a stereromicroscope (Leica Biosystems). Results. When analyzing the tensile strength of the various groups of sutures, it was evidenced that PG maintained its strength, which was lowest at baseline and highest at 21 days. When performing the statistical inference of PG and PTFE, it was found that the force necessary to achieve detachment was not statistically significant (p<0.05). However, it was shown that the force necessary to achieve rupture in the BS group was statistically significant (p=0.001). Conclusion. To sum up, when comparing the in vitro tensile strength of PG, BS, and PTFE sutures at baseline and 3, 7, 14, and 21 days, there was no statistically significant difference. This indicates that all sutures used present sufficient performance that remains resistant as time progresses.

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A Comparative Evaluation of Static Frictional Resistance Using Various Methods of Ligation at Different Time Intervals: An In Vitro Study

International Journal of Dentistry ◽

10.1155/2015/407361 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Amanpreet Singh Natt ◽

Amandeep Kaur Sekhon ◽

Sudhir Munjal ◽

Rohit Duggal ◽

Anup Holla ◽

...

Keyword(s):

Stainless Steel ◽

Artificial Saliva ◽

In Vitro Study ◽

Frictional Resistance ◽

Static Friction ◽

Significant Difference ◽

Dry Conditions ◽

The Mean ◽

Time Periods

Aim. To compare and evaluate the static frictional resistance offered by the four different types of ligation methods in both dry and wet conditions and at different durations when immersed in artificial saliva.Material and Methods. Alastik Easy to Tie modules, Super Slick Mini Stix elastomeric modules, Power “O” modules, and 0.009″Stainless Steel ligatures were used to compare the static friction using maxillary canine and premolar Preadjusted Edgewise brackets with 0.022″× 0.028″slot and 0.019″× 0.025″stainless steel wires.Results. The mean frictional resistance for Alastik modules was the lowest and that of Stainless Steel ligatures was found to be highest among the four groups compared and the difference among the four groups was statistically significant (P<0.005). The mean static frictional resistance in all groups under dry conditions was lower than that under wet conditions. No statistical significant differences were found when the groups were compared at different time periods of immersion in artificial saliva.Conclusion. This study concludes that the Alastik modules showed the lowest mean static frictional forces compared to any other ligation method, though no significant difference was found for different time periods of immersion in the artificial saliva.

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Assessment of Bisphenol A Release by Orthodontic Aligners : In Vitro Study

Integrative Journal of Medical Sciences ◽

10.15342/ijms.7.278 ◽

2020 ◽

Vol 7 ◽

Author(s):

Intissar El Idrissi ◽

Houda Bouchafra ◽

Fatima Zaoui ◽

Amine Cheikh ◽

Moulay Abbes Faouzi ◽

...

Keyword(s):

Bisphenol A ◽

High Performance ◽

Artificial Saliva ◽

In Vitro Study ◽

Scientific Data ◽

Vitro Study ◽

Technological Advances ◽

Clear Aligner ◽

To Receive

Background : In orthodontic practice, for several years we have witnessed the rise of orthodontics for adults who are particularly concerned about their appearance and who most often refuse conventional metal multi-brackets. Technological advances and new materials currently allow patients to receive orthodontic treatments with invisible devices, namely orthodontic aligners. Although the thermoplastic materials that make up these aligners are biocompatible, they are not inert; In order to protect the health of our patients, it has been proposed to demonstrate a possible release of bisphenol A (BPA) by orthodontic aligners and to determine its concentration through an in vitro study. Methods : Our sample consisted of 10 new orthodontic aligners "SCHEU Dental Clear Aligner®" and 10 aged orthodontic aligners from the same supplier recovered after an average stay in the mouth of 15 days. Each aligner was immersed in 30 ml of artificial saliva. Samples were taken regularly for 2 weeks to monitor a possible release of bisphenol over time by high performance liquid chromatography (HPLC).Results : Interpretation of the chromatograms of bisphenol samples in new and aged aligners did not show traces of bisphenol for up to 8 weeks.Conclusion: Further research with a larger sample and a longer duration will lead to more conclusive results since current scientific data report effects at very low doses.

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Long-Term Sorption and Solubility of Zirconia-Impregnated PMMA Nanocomposite in Water and Artificial Saliva

Materials ◽

10.3390/ma13173732 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3732

Author(s):

Saleh Zidan ◽

Nikolaos Silikas ◽

Julfikar Haider ◽

Julian Yates

Keyword(s):

Artificial Saliva ◽

Statistical Tests ◽

In Vitro Study ◽

Acrylic Resin ◽

High Impact ◽

Control Group ◽

Denture Base ◽

Significant Difference ◽

Zirconia Nanoparticles

Exposure of denture base acrylic resins to the oral environment and storage media for extended periods of time results in sorption of saliva or water, leading to a reduction in physical properties and thus clinical service life. The purpose of this in vitro study was to assess the sorption and solubility of high-impact heat-polymerised denture base acrylic resin (HI PMMA) impregnated with zirconia nanoparticles after being stored for 180 days in distilled water (DW) and artificial saliva (AS). The specimens were divided into six groups for each storage medium, according to the concentration of zirconia nanoparticles (0, 1.5, 3.0, 5.0, 7.0, and 10.0 wt.%). Data were statistically analysed for sorption and solubility using one-way and two-way ANOVA statistical tests. Sorption in DW and AS for all groups containing zirconia showed sorption values lower than the control group at 90 days, though not significantly different (p > 0.05) compared to the control group. For both the DW and AS groups, the lowest solubility value was measured in the group containing 3 wt.% zirconia, however, there was no significant difference compared to the control group except when observing 10 wt.% zirconia in AS, which showed a significantly higher solubility (p < 0.05). High-impact PMMA, impregnated with low concentrations of ZrO2, showed the lowest sorption and solubility in both media, but was not significantly different compared to pure HI PMMA.

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Bond strength of orthodontic adhesives to dry and saliva-moistened enamel – a comparative in vitro study

Archives of Materials Science and Engineering ◽

10.5604/01.3001.0013.2388 ◽

2019 ◽

Vol 2 (96) ◽

pp. 79-84

Author(s):

T. Stefański ◽

A. Kloc-Ptaszna ◽

L. Postek-Stefańska

Keyword(s):

Composite Materials ◽

Bond Strength ◽

Artificial Saliva ◽

In Vitro Study ◽

Clinical Situation ◽

Cyanoacrylate Adhesive ◽

Significant Difference ◽

Materials Research ◽

Mandibular Third Molars

salivamoistened enamel. Design/methodology/approach: One hundred twenty stainless steel brackets were bonded to human mandibular third molars with six materials: Enlight LC® (Ormco Corp), Grengloo® (Ormco Corp), Light Bond® (Reliance Orthodontic Products), Charisma® (Heraeus Kulzer), SmartBond® (Gestenco), and Transbond XT® with MIP® primer (3M Unitek). One half of the specimens in each group (n=10) was bonded to dry enamel, while the other half to saliva-moistened enamel. Bond strength testing was performed with a wire loop loading technique after 30-min incubation in artificial saliva. Failure mode was evaluated using adhesive remaining index (ARI). Findings: No significant differences in bond strength to dry enamel were noted for all composite materials (p>0.05). SmartBond exhibited significantly greater bond strength to moistened enamel (7.10 ± 1.47 MPa) and comparable with other composite materials to dry enamel. Composite materials demonstrated significantly reduced bond strength to saliva-moistened enamel (p<0.001), except for Transbond MIP, whose bond strength was not significantly decreased by saliva contamination (p=0.089). There was not statistically significant difference between bond strength of SmartBond and Transbond to saliva contaminated enamel. A higher incidence of cohesive failures was noted for all materials. Research limitations/implications: Composite light-cured materials provide adequate bond strength to dry enamel. Cyanoacrylate adhesive provides sufficient bond strength only under moist conditions. Transbond XT+MIP has sufficient bond strength to either dry or saliva-moistened enamel. Practical implications: The study evaluated the bonding strength of orthodontic brackets, which is a critical parameter in orthodontics, especially in situations that do not allow for proper isolation from saliva, such as bonding to impacted teeth following surgical exposure. Originality/value: Bond strengths evaluated with loop loading technique in different study environments would help the orthodontist to choose the most effective adhesive for the specific clinical situation.

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Comparison the effect of charcoal-containing, hydrogen peroxide-containing, and abrasive whitening toothpastes on color stability of a resin composite; an in vitro study

BMC Oral Health ◽

10.1186/s12903-021-01956-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Sara Mehrgan ◽

Hamid Kermanshah ◽

Ladan Ranjbar Omrani ◽

Elham Ahmadi ◽

Niyousha Rafeie

Keyword(s):

Hydrogen Peroxide ◽

Resin Composite ◽

Artificial Saliva ◽

In Vitro Study ◽

Color Stability ◽

Blue Color ◽

Yellow Color ◽

Significant Difference ◽

Color Shift

Abstract Background This study aimed to compare the effects of charcoal-containing, hydrogen peroxide-containing, and abrasive whitening toothpastes on color stability of a resin composite. Methods Forty-five specimens were fabricated of spectrum TPH3 composite resin and stored in artificial saliva for 24 h. Baseline color assessment was performed using a spectrophotometer device. Then, the specimens were randomly assigned into 5 experimental groups, namely distilled water (GC), Bencer (GB), colgate optic white (GO), perfect white black (GP) and colgate total whitening (GT) toothpastes. The specimens immersed in coffee solution for 10 min and brushed for 1 min with respective toothpaste and then stored in artificial saliva until the next day. This cycle was repeated for 30 days. After 30 days, the final color assessment was performed using the spectrophotometer. Data were analyzed using one-way ANOVA and Tukey tests. Results Experimental groups were not significantly different in terms of Δa and ΔE values. However, ΔL and Δb values showed significant difference among the groups. Regarding Δa, GT and GC groups showed red color shift while the other groups showed green color shift. Regarding Δb, all groups showed blue color shift except GT group which showed yellow color shift. Conclusion None of the whitening toothpastes could decrease discoloration caused by the coffee solution to the level below the perceptibility threshold except Colgate Optic White which reduced discoloration within the clinically acceptable perceptibility range.

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In Vitro Study of Nicotine Release from Smokeless Tobacco

Journal of AOAC International ◽

10.1093/jaoac/81.3.540 ◽

1998 ◽

Vol 81 (3) ◽

pp. 540-543 ◽

Cited By ~ 3

Author(s):

Moheb M Nasr ◽

John C Reepmeyer ◽

Yubing Tang

Keyword(s):

Smokeless Tobacco ◽

Direct Contact ◽

Artificial Saliva ◽

In Vitro Study ◽

Reversed Phase ◽

Tobacco Products ◽

Significant Difference ◽

Smokeless Tobacco Products ◽

Dialysis Bag

abstract Four brands (Copenhagen Snuff, Skoal Bandit Classic, Skoal Wintergreen Long Cut, and Skoal Wintergreen Fine Cut) of smokeless tobacco products were tested for their rate of nicotine release into artificial saliva via direct contact or through a dialysis bag. Nicotine was determined by reversed-phase liquid chromatography. When samples were in direct contact with artificial saliva, most of the nicotine was released from the tobacco in the first minute. Nicotine release from Skoal Bandit Classic, marketed as smokeless tobacco in a sachet, was slower with the sachet intact than without the sachet. When smokeless tobacco and artificial saliva were placed inside a dialysis bag, nicotine release was much slower and primarily depended upon the permeability of the dialysis membrane. Although total nicotine was lowest for Skoal Bandit Classic, little difference was seen in nicotine release rates among the brands tested. When smokeless tobacco was placed in dialysis bags with artificial saliva outside, a significant difference was seen in rates of nicotine migration through the membrane. In this model, nicotine release from Copenhagen Snuff was much faster than from Skoal Bandit Classic with or without the sachet. This difference may be related to the pH of the smokeless tobacco products.

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Effect of Artificial Saliva Contamination on Bond Strength to Pulp Chamber Dentin

European Journal of Dentistry ◽

10.1055/s-0039-1697360 ◽

2008 ◽

Vol 02 (02) ◽

pp. 086-090 ◽

Cited By ~ 7

Author(s):

Hale Ară ◽

Nazmiye Dönmez ◽

Sema Belli

Keyword(s):

Bond Strength ◽

Artificial Saliva ◽

In Vitro Study ◽

Adhesive System ◽

Control Group ◽

Pulp Chamber ◽

Significant Difference ◽

Group 2 ◽

Saliva Contamination

ABSTRACTObjectives: The purpose of this in vitro study was to evaluate the effect of artificial saliva contamination on microtensile bond strength to pulp chamber dentin.Methods: Clearfil SE Bond (SEB) (Kuraray, JAPAN) adhesive system and Clearfil Photo Posterior (CPP) (Kuraray, JAPAN) composite resin were used. Twenty extracted caries-free human molar teeth were randomly distributed into four groups. Apart from a control group without contamination (Group 1), primed dentin surfaces were contaminated with artificial saliva (10 s), rinsed, dried, reprimed and bonded (Group 2), coated with adhesive, contaminated with artificial saliva, rinsed, dried, bonding procedures were repeated (Group 3), coated with adhesive, light cured, contaminated with saliva, rinsed, dried, treated with SE primer (SEP) and SEB (Group 4).After 24 hrs, the teeth were prepared for microtensile bond testing and tensile bond strength was measured (1mm/min). The data was calculated as MPa and analyzed using one-way ANOVA and Duncan test (P<.05).Results: The results indicated that Group 2 showed lowest bond strength when compared to the others (P<.05). No statistically significant difference was found between Groups 3 and 4 (P>.05).Conclusions: It was concluded that contamination during priming procedure has a negative effect on bond strength (P<.05). Although contamination of the uncured adhesive was not critical in this study (P>.05) any kind of contamination of the bonding area should, in principle, be avoided. (Eur J Dent 2008;2:86-90)

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