TransbondTM Plus Research Articles

Reduction of surface treatment time by combination of citric acid and ascorbic acid while restoring shear bond strength of metal brackets bonded to bleached enamel: a pilot study

BackgroundTo investigate the effect of a 50% ascorbic acid with 50% citric acid solution on the immediate shear bond strength (SBS) of metallic brackets after tooth bleaching. The enamel etching pattern and the required quantity of these combined acids as antioxidants following 35% hydrogen peroxide (HP) bleaching were also determined.MethodsThe stability of the solution at room temperature was assessed at various time intervals. Fifty teeth were randomly divided into five groups: non-bleached (G1), bleached then acid etched (G2), bleached followed by a 10-minute treatment with 10% sodium ascorbate and acid etched (G3), 5-minute treatment with 50% ascorbic acid (G4), and 5-minute treatment with a combination of 50% ascorbic acid and 50% citric acid (G5). Groups G2, G3, G4 and G5 were bleached by 35% HP gel for a total of 32 min. Acid etching in groups G1, G2, and G3 was performed using 37% phosphoric acid (Ormco®, Orange, CA, USA) for 15 s. In all groups, metal brackets were immediately bonded using Transbond™ XT primer and Transbond™ PLUS adhesive, with light curing for 40 s. The SBS was tested with a universal testing machine, and statistical analysis was conducted using one-way ANOVA followed by Tukey’s HSD test. The level of significance was set at p < 0.05 for all statistical tests.ResultsStability tests demonstrated that the combined acids remained effective for up to 21 days. Group G5 significantly increased the SBS of bleached teeth to the level of G1 (p < 0.05), while G3 did not achieve the same increase in SBS (p > 0.05). SEM analysis revealed enamel etching patterns similar to those of both control groups (G1 and G2). Kinetic studies at 6 min indicated that the antioxidation in G5 reacted 0.2 mmole lower than in G3 and G4.Conclusion5-minute application of the combined acids enhanced the SBS of bleached teeth comparable to unbleached teeth. The combined acids remain stable over two weeks, presenting a time-efficient, single-step solution for antioxidant application and enamel etching in orthodontic bracket bonding.

The effect of different enamel surface preparations on microleakage under orthodontic brackets

Microleakage is caused by many factors, including polymerization shrinkage of the resin, thermal expansion differences between the enamel and the adhesive, and inadequate adherence. This study aims to assess the microleakage value under orthodontic brackets after three distinct enamel surface preparations and compare the results to the traditional procedure. Fifty-four intact upper premolars were randomly distributed into three groups. First group 18 teeth etched with 36% phosphoric acid Dentsply. Second group 18 teeth etched with %1.23 acidulated phosphate fluoride (APF) incorporated phosphoric acid 25%APF 75%phosphoric acid Dentsply. Third group 18 teeth etched with Trans Bond TM Plus Self-Etching prime 3M Unitek, Monrovia, USA. Then, according to the manufacturer's instructions, all groups bonded to stainless steel brackets RAZOR, IOS, USA, using light-cured composite 3M Unitek/ Monrovia, USA. Then, each subgroup was divided into 3 subgroups, 6 teeth each. The first subgroup thermocycled 500 cycles between 5 C and 55 UC in deionized water and tested after 24 hours of water storage. The second subgroup was also thermocycled and tested after 2 months of water storage. The third subgroup was subjected to cyclic acid attack for 2 months by an acidic solution pH=2.5. Microleakage was evaluated using a dye penetration technique. All samples are sectioned and evaluated under a stereomicroscope. For statistical analysis, the Kruskal-Wallis test was employed. P=0.05 was the level of significance. A significant difference was between etching groups following a thermocycler and a twenty-four-hour water storage, no significant difference after thermocycling and two months of water storage, and significant difference at the occlusal side and between overall means of compared etching groups. This study revealed that the highest microleakage values were in the SEP self-etch prime group, then EF 1.23% APF incorporated phosphoric acid group and the ER 36% phosphoric acid group. The gingival side had more microleakage than the occlusal side. Adding around 20-25 percent of 1.23 percent of phosphoric acid for enamel preparation before orthodontic bonding increases microleakage values, but SEP remains the highest. Keywords: Microleakage, Self-etch prime, Acidulated phosphate fluoride, Stainless steel brackets

Evaluation of shear bond strength of orthodontic adhesives with integrated primer: A comparative study

Objectives: The study aimed to compare the shear bond strength (SBS) of three orthodontic adhesives with integrated primer, with those of self-etching and conventional bonding adhesives. Material and Methods: One hundred extracted premolars were randomly allocated to five groups. Brackets were bonded using three adhesives with integrated primer (GC Ortho Connect™, Biofix, and Orthocem). A group of brackets was bonded with the conventional bonding procedure (Transbond XT) and one group was bonded with a self-etching primer (Transbond™ Plus). All samples were subjected to thermal aging (5000 cycles: At 5°C and 55°C media). The compressive strength test was performed and the maximum load when the bracket detached was recorded. The amount of residual adhesive (ARI) remaining on the tooth surface was assessed visually. Results: Significantly higher SBS values were recorded with the conventional technique (14.01 ± 5.79 megapascals [MPa]), compared to other groups except for GC Ortho Connect™ (11.86 ± 3.83 MPa). There was no significant difference between the self-etching group and the groups containing integrated primer samples. However, one of the adhesives with integrated primer presented SBS values near-slightly below the limit considered clinically successful (7.65 ± 3.71 MPa). The ARI scores varied between adhesive groups; GC Ortho Connect™ and the self-etching primer samples showed statistically significantly higher scores compared to the three other groups. Conclusion: Clinically successful bonding values were achieved with two out of three different adhesives with integrated primer. One of the adhesives with integrated primer provided a similar SBS value to the tri-step conventional bonding procedure. ARI scores varied independently from SBS values.

Do Different Types of Adhesive Agents Effect Enamel Demineralization for Orthodontic Bonding? An In Vitro Study

(1) Objective: The aim of this study was to compare the demineralization around brackets bonded with different types of adhesive agents in a cariogenic suspension environment. (2) Methods: In the study, 60 extracted upper first premolar teeth were divided into three groups with 20 teeth in each group. In Group 1, Transbond XT Primer + Transbond XT Light Cure Adhesive (3M Unitek, Monrovia, CA, USA), in Group 2, GC Ortho Connect Light Cure Adhesive (GC Crop, Tokyo, Japan) and in Group 3, Transbond™ Plus Self Etching Primer + Transbond XT Light Cure Adhesive (3M Unitek, Monrovia, CA, USA) adhesive agents were used. In Group 1 and 2, buccal enamel surfaces were etched for 30 s, washed for 15 s and dried for 15 s. All groups were bonded with Gemini metal (3M Unitek, Monrovia, CA, USA) brackets. Gingival, occlusal and proximal enamel surfaces of the brackets were measured with a DIAGNOdent pen (KaVo, Biberach, Germany), and demineralization values were recorded. Measurements were performed after bracketing (T0) and after 28 days in a cariogenic environment (T1), which was renewed every 48 h. The Kolmogorov–Smirnov test was used to determine whether or not the data were homogeneously distributed, the Wilcoxon test was used for comparisons within groups, and the Mann–Whitney U and Kruskal–Wallis tests were used for comparisons between groups. (3) Results: In all groups, demineralization values on all enamel surfaces of the brackets were found to be statistically significantly higher in the T1 period than in the T0 period (p &lt; 0.05). In the T1 period, demineralization values of occlusal enamel surfaces in Groups 1 and 2 were found to be significantly higher than in Group 3 (p &lt; 0.05). The amount of increase in occlusal enamel surface demineralization value between T0 and T1 periods in Groups 1 and 2 was significantly higher than in Group 3 (p &lt; 0.05). There was no statistically significant difference in demineralization values of proximal and gingival enamel surfaces between the groups in the T1 period (p &gt; 0.05). (4) Conclusion: Significantly less occlusal enamel surface demineralization was observed in teeth in which the Transbond™ Plus Self Etching Primer adhesive agent was not applied with acid etching.

Evaluation of the shear bond strength and adhesive remnant index of color change, fluorescent, and conventional orthodontic adhesives: An in vitro study

To investigate the in vitro performance of colour change orthodontic adhesive (CCOA) or fluorescent orthodontic adhesive (FOA), conventional orthodontic adhesives (COA), and the mixed CCOA and FOA utilizing the shear bond strength (SBS) and adhesive remnant index (ARI). Ninety extracted first premolars were used in the study. Four manufacturers of orthodontic adhesive were used, including Transbond™ XT (TBXT) and Transbond™ plus (TBP) (3M™ Unitek™, CA, United States), Ormco Enlight™ (OE) and Greengloo™ (GG) (Ormco™, CA, United States), Light Bond Medium™ (LBM), and GoTo™ (GT) (Reliance orthodontic products®, IL, United States), and BracePaste® Adhesive (BPA) and BracePaste® Colour Change (BPCC) (American orthodontics®, WI, United States). The mixed orthodontic adhesive of Transbond™ plus and GoTo™ (TBPGT) was prepared to evaluate the combined effect of colour change and fluorescent orthodontic adhesives. Peak SBS was recorded using a universal testing machine. ARI was measured using a stereomicroscope under 10x magnification. Descriptive statistical analysis and comparative tests were used to evaluate the results. All CCOA and FOA had higher mean SBS than COA. The highest value of SBS was obtained in BPCC (23.56MPa), and the lowest value in TBPGT (11.41Mpa). One-way ANOVA multiple comparisons and Duncan's multiple range test showed that TBXT and TBPGT significantly differed in SBS with GT, GG, TBP, and BPCC, respectively (P=0.016). Kruskal-Wallis multiple comparisons test showed no significant differences in ARI among the tested adhesives (P=0.089). Colour Change Orthodontic Adhesive (CCOA) and Fluorescent Orthodontic Adhesive (FOA) showed a higher SBS than conventional orthodontic adhesives. GreenglooTM had the lowest ARI among the groups tested. All adhesives tested can be safely used in orthodontic practice, and both CCOA and FOA showed better performance than COA. The TransbondTM plus and GoToTM (TBPGT) mixed adhesives showed the lowest performance in terms of SBS and ARI.

Bond strength, degree of conversion, and microorganism adhesion using different bracket-to-enamel bonding protocols.

This study aimed to evaluate the effect of bonding protocols and the type of orthodontic resin on the adhesion of microorganisms, degree of conversion (DC), and shear bond strength (SBS) of metallic brackets to enamel. Atotal of 60bovine incisors were prepared and randomly divided into 6groups (n = 10): "bonding protocol" (A:phosphoric acid; AXT:A+Transbond™ XT primer adhesive [all Transbond™ products from 3M Unitek, Monrovia, CA, USA]; and SE:Transbond™ Plus Self Etching Primer) and "orthodontic resin" (XT:Transbond™ XT adhesive paste and CC:Transbond™ Plus Color Change). After bonding, the samples were subjected to thermocycling (5000cycles) and to the SBS test. Bond failures were classified according to the adhesive remnant index (ARI). Next, 60enamel blocks were sterilized in ethylene oxide in order to perform the CFU (Streptococcus mutans) assay in vitro to analyze the colony forming units (CFU/mL). Then, 60discs of each orthodontic resin were made to measure the DC. The SBS (MPa), CFU/mL, and DC (%) data were statistically analyzed by two-way analysis of variance and Tukey's test (5%) was performed for the DC. CFU and SBS revealed no significance for all factors (P > 0.05). Tukey's test showed that A_XT (acid+Transbond™ XT adhesive paste) presented the highest DC (70.38% ± 10.5), while AXT_XT (acid+Transbond™ XT primer adhesive+Transbond™ XT adhesive paste) showed the lowest (23.47% ± 10.4). An ARI score of2 was more frequent for the CC resin and an ARI score of4 for the XT resin. The CC resin does not reduce adhesion of S. mutans around orthodontic brackets and the bonding protocol did not influence the SBS, although the SE and A_XT groups contributed to abetter DC.

Correlation between dental enamel chemical composition and bracket debonding, comparing adhesive systems through a scanning electron microscope.

Literature reports indicate that during bracket removal there can be enamel damage. We compare the shear bond strength (SBS) and tooth enamel loss of four adhesive systems and identify the Ca/P ratio. Then a total of 20 premolars were divided into four groups of five each. After prophylaxis, photographs were taken at 35× with a scanning electron microscope (SEM) and analyzed with X-ray spectroscopy (EDS) at 250×. Brackets were bonded with Transbond™ MIP(G1), Transbond™ PLUS SEP(G2), Enlight(G3) and Stylus®(G4) adhesives, 24 h after were debonded with a Instron universal testing machine at 1 mm/min. All the brackets were photographed with the SEM. The amount of lost enamel was measured with AutoCad. All the results were measured with a significance level p < .05. The SBS general average at debonding was 7.94 ± 2.26 MPa, meanwhile the SBS for G1, G2, G3 and G4 was 9.38 ± 1.46, 6.28 ± 0.69, 9.08 ± 2.45 and 7.04 ± 2.64 MPa respectively. 90% of the samples had no enamel loss, 10% had enamel loss. Only two samples in G1 presented an enamel loss area of 0.34mm2 and 0.80mm2 respectively. From EDS analysis, the Ca/P ratio was 1.6 ± 0.05, 1.61 ± 0.03, 1.64 ± 0.83 and 1.59 ± 0.07 for G1, G2, G3 and G4 respectively; no statistically significant differences were found. We conclude that no association was found between the Ca/P ratio and enamel damage when brackets are removed. HIGHLIGHTS: Where enamel is lost, we observe fractures, steps, horizontal and vertical enamel loss. There is a loss of tooth enamel from 0.34 to 0.80 mm2 with Transbond PLUS SEP. Structural loss of enamel is almost inevitable during the separation of the bracket.

Assessment of the Effectiveness of Different Fluoride-releasing Bonding Agents on Prevention of Enamel Demineralization around Orthodontic Bracket: An In Vitro Study

The aim of the current research was to evaluate the efficacy of different fluoride-releasing bonding products in preventing enamel demineralization around orthodontic brackets by using a scanning electron microscope (SEM). This research was performed using 80 healthy human premolar teeth that were extracted in course of orthodontic therapy. Until use, the sample premolars were subjected to storage in 0.1% thymol. Each premolar was thereafter cleansed with pumice for 10 seconds. Stainless steel brackets for premolars were employed. The 80 samples were allocated at random to one of the four groups (20 in each) as follows: Group I, control; group II, Transbond Plus color change adhesive; group III, GC Fuji Ortho LC; and group IV, Vitremer. An hour following bonding, all samples were subjected to pH cycling at a temperature of 37°C for a 14-day period. The premolar teeth were assessed below SEM. Analysis was performed with the one-way analysis of variance. Statistical significance was set at a p-value less than 0.05. The extreme area of demineralization was abridged by the use of Transbond™ Plus color change adhesive (108.19 ± 0.68), trailed by GC Fuji Ortho LC (119.24 ± 0.37) use, Vitremer (121.56 ± 0.92) as well as the control group (141.88 ± 1.09) in that order. And there was a statistically significant difference found between the groups (p <0.001). Tukey's honestly significant difference (HSD) was employed in an overall comparison of mean areas of enamel demineralization, which depicted that differences were significant statistically with the exception of group III and group IV. The current research came to a conclusion that the Transbond Plus color change adhesive group was more potent in significant inhibition of demineralization areas in comparison to GC Fuji Ortho LC group and Vitremer group. In course of fixed orthodontic therapy, demineralization of enamel is an inherent occurrence. Multiple approaches are being continually developed to avoid the formation of white spot lesions (WSLs) that compromise esthetics and cause deprived remineralization that enhances the menace of dental caries. Bonding agents that can release fluorides are thus considered highly efficacious.

Effect of using different component combinations for orthodontic bracket bonding with self-etch primers.

To evaluate bonding quality for orthodontic bracket bonding with different component combinations of self-etch primers in vitro. Metallic brackets were bonded to bovine lower incisors and assigned to groups. Group1: comparison of self-etch (Transbond™ Plus, 3M™ Unitek, Neuss, Germany, n = 30; BrackFix® primer SE, VOCO®, Cuxhaven, Germany, n = 20) and etch-and-rinse bonding systems (Transbond™ XT, n = 20; BrackFix®, n = 20); group2: comparison of different self-etch primer (Transbond™ Plus; BrackFix® primer SE) and adhesive (Transbond™ XT, n = 20; BrackFix®, n = 20) product combinations; group3: testing cyclic fatigue bond strength of self-etch bonding systems (Transbond™ Plus, n = 20; BrackFix® primer SE, n = 20). All teeth were tested for shear bond strength according to the DIN-13990 standard, the adhesive remnant index (ARI) and enamel fractures were determined microscopically (10 ×magnification). The mean shear bond strength of the self-etch (Transbond™ Plus: 16.38 ± 3.68 MPa; BrackFix® primer SE: 16.24 ± 1.73 MPa) and etch-and-rinse bonding systems (Transbond™ XT: 18.45 ± 2.56 MPa; BrackFix®: 17 ± 5.2 MPa) were of aclinically adequate order of magnitude (≥ 6-10 MPa) and were not statistically different. The component combination BrackFix® primer SE/Transbond™ XT adhesive led to asignificantly lower shear bond strength (11.99 ± 3.68 MPa). There were no significant differences between static and fatigue shear bond strengths of self-etch bonding systems. Mean ARI scores mostly ranged between4 and5. The combination of the self-etch primer Transbond™ Plus with the BrackFix® adhesive led to asignificantly increased enamel fracture rate. Based on the present findings bond strength of self-etch primers was equal to etch-and-rinse primers for bracket bonding. Combining different self-etch bonding systems might alter the clinical performance.

In vitro comparison of wear of three orthodontic bite materials and opposing enamel

Orthodontic bite turbos are used to separate the maxillary and mandibular arch when disocclusion is needed for brackets placement or extrusion of teeth. Bite turbos should have adequate wear resistance to maintain disocclusion but also avoid abrasion of the opposing enamel. The objective of this study was to measure the wear of three materials used as bite turbos and opposing enamel wear. 10mm×8mm×4mm specimens (n=8) of Transbond™LR (3M™) Transbond™ Plus (3M™) and Triad®gel (Dentsply) were prepared in silicone molds. Cusps of extracted premolars were prepared to a standard cone shape. Extracted maxillary incisors were used as reference for flat enamel surfaces. The experiments were performed on the modified UAB wear testing device at 20N for 200,000 cycles at 1Hz. All surfaces were scanned with a non-contact profilometer at 10micron resolution. Volumetric wear was measured with superimposition software and data analysed with one-way ANOVA and Tukey post-hoc. Significant differences were seen in the wear of materials and opposing enamels (P<.01). Material wear ranked: Triad®gel (.878±.196mm3)>Transbond™ Plus (.317±.062mm3)>Transbond™ LR (.136±.027mm3)>Enamel (.053±.04mm3). Opposing enamel ranked: Transbond™ LR (.158±.086mm3)=Enamel (.128±.035mm3)=Transbond™ Plus (.126±.025mm3)>Triad®gel (.039±.008mm3). All bite turbo materials wore more than natural enamel but caused equal or less wear to opposing enamel than tooth-tooth contact. Triad®gel underwent 2.5× and 6× the wear of Transbond™ Plus and Transbond™ LR respectively. The bite turbo material used may be selected based on preference for longevity.

Influence of Polymerization with Argon Laser and LED on Shear Resistance of Adhesive Systems

objective: The aim of this work was to evaluate the shear strength of ceramic brackets as a function of two adhesive systems (kit TransbondTM XT; TransbondTM Plus Self Etching Primer/ 3M Unitek®) and two light sources (LED and Argon Laser). Method: 28 maxillary premolars were used, divided into two groups (n=14), according to the adhesive system and light source. The teeth were enclosed in ¾-inch PVC tubes, with special stone plaster, perpendicular to the ground and tubes. Brackets were fixed over the exposed crowns. The teeth were stored at 37ºC for 24 hours and then submitted to 1,000 thermal cycles with 30 seconds in each bath (5°C and 55°C). The shear test was performed on a Shimadzu® testing machine at a speed of 0.5mm/min. Enamel surfaces were qualified using the ARI (Adhesive Remaining Index). Data were submitted to statistical analyzes ANOVA, Tukey and Kruskal-Wallis (p&lt;0.05). Results: the conventional TransbondTM XT kit adhesive system was superior to the self-etching system. LED and Argon Laser showed similar behaviors. Conclusion: Argon laser did not influence shear strength or ARI scores.

Elution study of acrylic monomers from orthodontic materials using high performance liquid chromatography(HPLC).

PurposeMain goal of the study was the identification and quantitative analysis of monomer elution from materials commonly used in fixed orthodontic therapy. Studies have shown severe health effects of monomers including cytotoxic, allergenic or mutagenic potential and endocrine changes. This in vitro study focusses primarily on five resins which are usually processed intraorally and remain in the oral cavity long-term.MethodsWe tested the elution of monomers from specimens (7.5 mm × 1.5 mm) immersed in artificial saliva at body temperature (37 °C) for 30 min to 5 weeks. The used method is in accordance with DIN EN ISO 10993-13. The five tested materials were BrackFix® (Voco GmbH, Cuxhaven, Germany), Triad®Gel (DeguDent GmbH, Hanau, Germany), and Transbond™ XT, LR and Plus (3M Unitek, Monrovia, CA, USA). All aliquots were analyzed using high performance liquid chromatography (HPLC). Data were statistically analyzed.ResultsAll five analyzed materials eluted substances over a period of 5 weeks. Identified substances included bisphenol A (BPA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA). BPA eluted from Transbond™ Plus, XT, LR and BrackFix®. The cumulated mean values after 35 days ranged from 16.04 to 64.83 ppm, depending on the material. TEGDMA eluted with a mean of 688.61 ppm from Transbond™ LR. UDMA with a mean of 1682.00 ppm from Triad®Gel. For each material the highest concentrations of all these substances were found in the first elution period. Other substances that were not equivocally identified or of low concentration also eluted.ConclusionUsing the described method, it is possible to qualitatively and quantitatively determine the in vitro elution of monomers from orthodontic materials. The concentrations of the substances identified were below the current maximum recommended intake. However, a cumulative effect and low-dose effects should be considered for both patients and dental professionals, especially for young patients. Measures to reduce exposure patients and practitioners are suggested.

Influence of dental erosion on shear bond strength of ceramic brackets bonded with two different adhesive systems: an in vitro study

This study aimed to analyze the shear bond strength (SBS) of ceramic orthodontic brackets bonded with two different adhesive systems to intact and eroded teeth. Ceramic brackets were bonded to 72 bovine central incisors divided into four groups, defined by two study factors: enamel condition (control group, kept in artificial saliva; and experimental group, eroded by using immersion cycles in Coke™ for 90 seconds, every six hours for five days), and adhesive system type (Transbond™ XT or Transbond™ Plus Color Change). Polycrystalline ceramic brackets were adhesively fixed on all specimens using the same light curing protocol. SBS was tested using 0.5 mm/min and the failure mode was classified. SBS data was analyzed using two-way ANOVA followed by Tukey test. The adhesive remnant index (ARI) scores were analyzed using Kruskal-Wallis test with Dunn's post-hoc pairwise comparison (α=0.05). Percentages of ARI scores between the groups were compared by Fisher’s exact test. Spearman's correlation coefficient was applied to investigate the correlation between ARI scores and SBS values. Only the adhesive system factor had significant effect on SBS (p=0.014), Transbond™ Plus Color Change showing higher values. No significance was found for enamel condition (p=0.665) or the interaction between adhesive system and enamel condition (p=0.055). ARI scores frequencies differed between groups (p&lt;0.001). The median ARI scores were statistically different for most comparisons among the groups. However, no significant correlation was found between ARI scores and SBS. In conclusion, the type of adhesive system affected the SBS of ceramic brackets to dental enamel, but the enamel condition, intact or eroded, had no significant effect. There was no correlation between ARI scores and SBS values, although eroded enamel tended to retain more adhesive after bracket removal.

Mean Shearing Stroke Frequency of Orthodontic Brackets under Cycling Loading: An In Vitro Study.

Based on the development of many adhesive systems and bonding techniques, bonding strength of orthodontic brackets has become even more important in modern clinical orthodontics. The aim of this study was to determine mean shearing stroke frequency of different orthodontic bracket types and bonding agents under cycling loading. Therefore, 10 different types of orthodontic bracket from 4 different brands were divided into 2 groups. Two different adhesives, namely Transbond™ XT etch-and-rinse for Group 1 and Transbond™ Plus self-etching-primer adhesive for Group 2 were considered. The brackets were tested under cycling loading force of 10-N and a crosshead speed of 300 mm/min and 40 cycle/min. The frequency of strokes that the brackets failed were determined and these data were analyzed by statistical analysis using an independent sample t-test and one-way analysis of variance (ANOVA). The level of significance was set at p < 0.05. Generally, differences between the frequency of shearing strokes of the bracket failures were found to be statistically significant depending on the type of adhesives and brackets (p < 0.05). The bonding technique for Group 1 was found to have a significantly higher shear bonding strength than Group 2. It is also seen that different types of bracket belonging to the same or different brands had different shear bonding strength. It may be concluded that: (i) all bracket types used in this study can be applied with both bonding techniques, (ii) in order to minimize the risk of hard tissue damage, ceramic brackets should be carefully bonded using the self-etching primary adhesive technique.

Remnant adhesive flash in orthodontic bonding systems with different characteristics.

Introduction: Excess of adhesive around brackets negatively impact oral health of orthodontic patients. Objective: Evaluate the influence of orthodontic bonding system in removal of adhesive flash around orthodontic brackets. Methods: Based on their characteristics, four orthodontic bonding systems were selected: lightcuring adhesive (G1 - TransbondTM XT); pink pigmented light-curing adhesive (G2- TransbondTM Plus Color Change); resin-modified glass ionomer cement (G3 - FujiOrthoTM LC); and auto-curing adhesive (G4 - ConciseTM). For each group (n=10), a single operator placed metal brackets on bovine teeth (n=40) and used an explorer tip to visually remove flash excess. After curing / setting, the sampleswere taken to a stereomicroscope and the Axio Vision 4.4 software was used to measure the area of remnant adhesive flash around each bracket. The quantitative data obtained was analyzed by the Kruskal-Wallis and Dunn’s post hoc test at = 0.05. Results: The results show that the resin-modified glass ionomer cement (G3) had a larger area of remnant material than the other groups. There was no statistical difference between the other groups (G1, G2, and G4), independently of pigmentation or curing technique. Conclusion: It was concluded that the use of a resin-modified glass ionomer cement results in a larger area of remnant flash excess, which can negatively impact oral health. Pigmentation and curing technique did not influence on remnant flash excess.

Effectiveness of Various Dental Varnishes in Prevention of Enamel Demineralization around Orthodontic Brackets: An In Vitro Study

The present study aimed to assess the efficacy of different dental varnishes in prevention of demineralization of enamel along the orthodontic brackets. A total of 60 premolars that do not have caries and were extracted for orthodontic purposes were used in this study. Transbond™ Plus was used to bond premolar brackets onto the treated surface of enamel. The teeth were then divided into three groups. Group I: Profluorid varnish, group II: CPP-ACP varnish, and group III: Duraflor™ varnish. A Vickers diamond indenter was used to assess the microhardness of the surface of enamel at baseline, fourth day, and seventh day. A slightly meaner surface microhardness (SMH; 334.20 ± 2.10) was seen in group III when compared with group I (332.16 ± 3.02) and group II (330.40 ± 2.02). The mean SMH was 342.02 ± 0.82 in group I on the fourth day which was slightly higher than that of the baseline values, followed by group III (339.48 ± 0.34) and group II (336.64 ± 1.14). No statistically significant differences were noted between the groups. A higher mean microhardness of 349.84 ± 0.66 was seen in group I on the seventh day, followed by group III (342.26 ± 1.08) and group II (338.18 ± 1.08). A statistically highly significant difference was seen between the groups. The present study concluded Profluorid varnish to have maximum potential to reduce demineralization of enamel followed by Duraflor and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) group. A most common clinical challenge encountered in orthodontic clinical practice is enamel demineralization or white spot lesion (WSL) development throughout the fixed appliance treatment. Thus, the information about several available varnishes is important to prevent demineralization in regular dental practice.

Effect of Saliva Contamination and sequencing time of curing the Transbond™ Plus Self Etching Primer on the Shear Bond Strength of Orthodontic Brackets

Effect of Saliva Contamination and sequencing time of curing the Transbond™ Plus Self Etching Primer on the Shear Bond Strength of Orthodontic Brackets

In vitro evaluation of microleakage under orthodontic brackets bonded with different adhesive systems.

Objective:Adhesives systems have a drawback when utilized for bonding orthodontic brackets: they shrink during photopolymerization creating microleakage. The aim of this study was to assess the stability of different orthodontic adhesives around brackets and enamel.Materials and Methods:Sixty noncarious mandibular premolars extracted for orthodontic reasons were randomly divided into six groups of adhesives used for bonding brackets to dental enamel: NeoBond® Light Cure Adhesive Kit, Transbond™ Plus Self-Etching, Victory V-Slot APC PLUS® + Transbond™ MIP, Rely-A-Bond® Kit, Light Cure Orthodontic Adhesive Kit (OptiBond®), and Transbond™ MIP. Following bonding, all teeth underwent 2500 cycles of thermal cycling in baths ranging from 5°C to 55°C before being immersed in 2% methylene blue for 24 h. All samples were examined under a binocular microscope to assess the degree of microleakage at the “bracket-adhesive” and “adhesive-enamel” interfaces in the gingival and occlusal regions of the bracket.Results:A significant difference was found at the “occlusal bracket-adhesive” interface. The highest microleakage values were found in the occlusal region, although no significant. Microleakage was observed in all groups.Conclusion:Group 2 had the highest microleakage values whereas Group 6 had the lowest values.

The influence of adding modified zirconium oxide-titanium dioxide nano-particles on mechanical properties of orthodontic adhesive: an in vitro study

BackgroundThe purpose of this in-vitro study was to examine the effect of incorporating different concentrations of Zirconium oxide-Titanium dioxide (ZrO2-TiO2) nanoparticles, which can have antibacterial properties, on the mechanical properties of an orthodontic adhesive.MethodsZrO2-TiO2 (Zirconium oxide, HWNANO, Hongwu International Group Ltd, China) -Titanium dioxide, Nanoshell, USA) nanopowder were incorporated into orthodontic adhesive (Transbond XT, 3 M Unitek, Monrovia, USA) with different concentrations (0.5% weight nonofiller and 1% weight nanofiller). The size of nanoparticle was 70–80 nm for ZrO2 and less than 50 nm for TiO2. For measuring the shear bond strength of the three groups of orthodontic adhesives [Transbond (control), Transbond mixed with 0.5% weight ZrO2-TiO2, and Transbond mixed with 1% weight ZrO2-TiO2], 30 freshly extracted human first premolars were used and bonded with stainless steel metal brackets (Dentaurum®, Discovery®, Deutschland), using the 3 orthodontic adhesives and 3 M Unitek; Transbond TM Plus Self-Etching Primer (10 samples in each group). The recorded values of compressive strength and tensile strength (measured separately on 10 samples of orthodontic adhesives (add the 3 D size of sample, light cured for 40 s on both sides) of each orthodontic adhesives), as well as the shear bond strength in Mega Pascal unit (MPa) were collected and exposed to one-way analysis of variance (ANOVA) and Tukey’s post-hoc tests.Resultsorthodontic adhesive with 1% weight ZrO2-TiO2 showed the highest mean compressive (73.42 ± 1.55 MPa, p: 0.003, F: 12.74), tensile strength (8.65 ± 0.74 MPa, p: 0.001, F: 68.20), and shear bond strength (20.05 ± 0.2 MPa, p: 0.001, F: 0.17).ConclusionsAdding ZrO2-TiO2 nanoparticle to orthodontic adhesive increased compressive strength, tensile strength, and shear bond strength in vitro, but in vivo studies and randomized clinical trials are needed to validate the present findings.

Effect of saliva contamination on cementation of orthodontic brackets using different adhesive systems.

BackgroundThe enamel condition and the quality of surface are points that need to be considered for achieving optimal efficiency in the treatment with orthodontic brackets. The aim of this study was to assess the immediate bond strength of metallic brackets cemented to dental.Material and MethodsForty human premolars were double-sectioned, placed in PVC matrices and randomly divided into 10 groups (n=8). They received artificial saliva contamination before or after the application of adhesive systems, except for the control groups. The metallic brackets were cemented using two orthodontic cements (Transbond™ Plus Color Change, 3M Unitek e Transbond™ XT Light, 3M Unitek). The specimens were subjected to mechanical shear bond strength testing and classified according to the fracture pattern. The results were analyzed using a two-way ANOVA and Tukey’s test for multiple comparisons (p<0.05).ResultsANOVA analysis showed statistically significant differences between the groups (p=0.01). The Tukey’s multiple comparison test indicated statistically significant difference between G6 and G7 groups (p<0.05). A high prevalence of adhesive failure in the groups receiving the hydrophobic adhesive system.ConclusionsThe saliva contamination prior to the application of a hydrophobic simplified conventional adhesive system was responsible for decreasing the immediate bond strength values of brackets cemented on the dental enamel. Key words:Bonding, orthodontic brackets, shear bond strength, saliva, adhesive systems.