Bond Strength Of Orthodontic Brackets Research Articles

The Effect of Er:YAG Laser on a Shear Bond Strength Value of Orthodontic Brackets to Enamel-A Preliminary Study.

We sought to evaluate the effects of Er:YAG laser (LightTouch, LightInstruments, Israel) conditioning on enamel roughness and shear bond strength of orthodontic brackets on enamel. Eighteen human molars (n = 9) and premolars (n = 9), were divided into 3 groups depending on the enamel conditioning method; Er:YAG laser (G1, n = 6), conventional etching with 37% orthophosphoric acid (G2, n = 6), Er:YAG laser combined with conventional etching (G3, n = 6). Er:YAG laser parameters were as follows: energy: 100 mJ, frequency: 10 Hz, exposure time: 10 s, applicator diameter: 600 μm, fluence: 35.37 J/cm2, distance: 1 mm away from a tooth, cooling: 80%. An MTS 858 MiniBionix® machine was used to determine the shear bond strength (MTS System, Eden Prairie, MN, USA). The enamel structure was assessed using X-ray microtomography (SkyScan 1172, Bruker, Kontich, Belgium). The highest values of shear bond strength were obtained in the G3 group (9.23 ± 2.38 MPa) and the lowest values in the G2 group (6.44 ± 2.11 MPa) (p < 0.05). A significant change in the enamel surface was noted after applying laser, reaching up to 9% of enamel thickness, which was not observed in the etched samples. Moreover, the Er:YAG laser-irradiated enamel surface was characterized by the greatest roughness. The combined use of an Er:YAG laser with a conventional etching improves the adhesion of composite materials to the tooth.

Characterization of a novel enamel sealer for bioactive remineralization of white spot lesions

Objectives45S5 Bioglass is a bioactive glass capable of releasing ions that can interact with dental hard tissues. The current study aimed at examining the effectiveness of 45S5 Bioglass in remineralizing enamel white spot lesion (WSL) as well as its effect on the bond strength of orthodontic brackets bonded to demineralized enamel. Materials and methodsWSLs were induced in the buccal surfaces of 135 human extracted teeth by storage in acid solution pH 4.5 for four days. The specimens were then equally divided into three groups; Demineralized group, Bioglass group (BG), and control group (intact enamel). The groups were chemically analyzed using (FTIR/ATR) Fourier-transform infrared spectroscopy/attenuated total reflectance, (XRD) X-ray diffraction, and (SEM/EDS) scanning electron microscope equipped with electron-dispersive-spectroscopy. Moreover, 10 specimens from each group were tested using Transverse Micro Radiography (TMR) technique, and 15 specimens from each group were bonded with metal orthodontic brackets and tested for shear bond strength test (SBS). The data were analyzed statistically using One way ANOVA p < 0.05. ResultsTMR study showed that bioglass group samples recorded lesion depth of 70.19 ± 29.21 μm and Δ Z (mineral loss) 732.15 ± 210.16 vol% μm which was significantly lower than the demineralized specimens having lesion depth of 115.75 ± 19.98 μm and Δ Z (mineral loss) 3472.69 ± 738.38 vol%μm, moreover, bioglass specimens recorded 14.15 ± 2.35 Mpa which was significantly higher than demineralized specimens 6.82+1.83 Mpa but less than the control specimens 20.5 + 6.1 MPa (p < 0.05). FTIR/ATR, XRD, and SEM/EDS tests showed that bioglass paste formed a layer of brushite crystals onto the treated enamel surface. Conclusion45S5 bioglass paste may serve as an effective remineralizing agent for demineralized enamel.

Shear bond strength of orthodontic brackets on intact and demineralized enamel after application of resin infiltrant, fluoride varnish and casein phosphopeptide-amorphous calcium phosphate remineralizing agents: in-vitro study

To evaluate the effects of remineralizing agents on the shear bond strength (SBS) of orthodontic brackets bonded to intact and demineralized enamel. In this in-vitro study, 160 human premolars were divided into 8 groups, including group 1 with intact enamel as the positive control, group 2 with demineralized enamel as the negative control, groups 3-5 treated with fluoride varnish, Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) and resin infiltrant on intact enamel, and groups 6-8 treated with the same agents on demineralized enamel. Brackets were bonded using the conventional method, and the samples were thermocycled. SBS of the brackets was measured using a universal testing machine, and the adhesive remnant index (ARI) was assessed. Data were analysed with one-way ANOVA and post hoc statistical test at the significance level of 0.05. SBS of the brackets in all groups with intact enamel was higher than that of their counterparts on demineralized enamel, which was only significantly different between groups 1 and 2 (P-value<0.001). SBS values of groups 7 and 8 were not significantly different from group 1 (P-value=1), yet the application of fluoride varnish on both intact (P-value=0.091) and demineralized enamel (P-value<0.001) created less SBS than in group 1. All pre-treatment methods increased SBS of the brackets bonded to demineralized enamel, yet only the resin infiltrant and CPP-ACP produced SBS similar to that of intact enamel. Also, the use of fluoride varnish on intact enamel significantly reduced SBS.

The effect of antimicrobial photodynamic therapy on shear bond strength of orthodontic bracket: An in vitro study.

The aim of this study was to evaluate the effect of antimicrobial photodynamic therapy (aPDT) with methylene blue (MB) and indocyanine green (ICG) on bond strength of orthodontic brackets to enamel. A total of 45 non-carious and sound human premolar teeth were used in this study. All teeth were examined under a stereomicroscope at ×10 magnification. The samples were divided to 3 groups including no treatment (control group), aPDT with MB and 660 nm diode laser and aPDT with ICG and 808 nm diode laser. After aPDT procedure, orthodontic brackets were bonded to enamel surfaces. Then, the samples were thermocycled for 5000 cycles between 5° and 55° C in water bath. The brackets were then debonded using a universal testing machine. The adhesive remnant index (ARI) score and SEM microscope evaluation were assessed. One-way analysis of variance (ANOVA) with Post-hoc test were used to compare the SBS values among groups. The highest SBS mean value was presented in group 1 (control) (31.98 ± 6.36). Whereas, the lowest SBS mean value was observed in group 3 (aPDT with ICG) (24.11 ± 5.78). There were significant differences in SBS values between control and aPDT groups (P < 0.05). Some superficial porosity and irregularity was presented following aPDT on surface of enamel when examined by scanning electron microscope. The mode of failure was mostly score 0 and score 1 in all groups. MB and ICG mediated antimicrobial photodynamic therapy both reduced the bond strength of orthodontic brackets compared to control group.

Bond strength of orthodontic brackets to polymethylmethacrylate: effect of the surface treatment and adhesive system

Objectives: To evaluate the influence of the surface treatment and adhesive system on the shear bond strength and the failure mode of orthodontic brackets bonded to polymethylmethacrylate surfaces. Methods: Ninety metal brackets (n=15) were bonded to aged discs of polymethylmethacrylate SR Ivocron subjected to three surface conditions (no treatment; sandblasting with 50-μm aluminum oxide; roughening with a tungsten bur), using two combinations of adhesives (methylmethacrylate monomer + Transbond XT Primer; Scotchbond Universal Adhesive) followed by the composite Transbond XT. In the control group, metal brackets were bonded with Transbond XT to 15 human mandibular incisors. The specimens were thermocycled, stored in distilled water (37ºC, 7 days), and tested in shear, using an Instron universal machine. Failure mode was classified according to the adhesive remnant index using a stereomicroscope. The data were analyzed with an analysis of variance and posthoc tests (p&lt;0.05). Results: Significant differences were found between the bracket bond strength to polymethylmethacrylate with different surface treatments (p&lt;0.001). Sandblasting with aluminum oxide was superior to tungsten bur roughening. The adhesive system did not significantly influence the shear bond strength nor the failure mode (p=0.8415). All experimental groups showed lower bond strengths than the control group (p=0.1566). Conclusions: Mechanical surface treatment significantly influenced the bracket’s bond strength to polymethylmethacrylate. Sandblasting with aluminum oxide was the most effective mechanical treatment. The weakest adhesive link was found at the acrylic-adhesive interface. Orthodontic bonding to polymethylmethacrylate was weaker than bonding to enamel, regardless of the surface treatment and the adhesive used.

An In Vitro Study to Compare the Shear Bond Strength of Orthodontic Brackets Bonded to Permanent Teeth by Using Conventional Acid-Etching and Self-Etching Primers

Objectives: The objective of the present study was to evaluate and compare the bond strength of orthodontic brackets bonded to permanent teeth with a conventional acid-etching and self-etching primer systems. Also, the study aims to evaluate the mode of bond failure after debonding the brackets. Materials and Methods: It was an experimental study. Fifty extracted permanent premolars were collected, checked, and cleaned. Teeth were split equally into two groups, group A and B. Orthodontic brackets were bonded using conventional acid-etching and self-etching primer systems for group A and B, respectively. Shear bond strength (SBS) was measured with a universal testing machine, and the mode of bracket-adhesive failure was determined by using adhesive remnant index (ARI). Data were analyzed with a statistical software. Independent sample t-test was used to compare the SBS and Mann–Whitney U test was used to assess whether there is a significant difference of ARI score between the groups. Results: Although the SBS with self-etching primer was within clinically acceptable range, the overall mean SBS for group A (14.71 MPa) was significantly greater than group B (9.24 MPa) (P = 0.024). There was no significant difference in ARI scores between conventional acid-etching and self-etching groups (P = 0.801). Conclusion: The SBS of the conventional acid-etching was significantly higher than the self-etching primer. The SBS of self-etch was within the acceptable range to withstand the forces of mastication. The majority of the brackets recorded ARI score of 1 indicating a cohesive failure with no significant difference between acid-etch and self-etch groups.

Effect of over-the-counter whitening strips and toothpaste on shear bond strength of orthodontic brackets.

BackgroundTo investigate: 1) the effects of over-the-counter white strip enamel bleaching and 2-Step whitening toothpaste application on the shear bond strength of orthodontic brackets at 24-hours and 7-days post-bleaching latent period; and 2) the correlation between amount of bleaching and shear bond strength. Material and MethodsSixty human premolar teeth were randomly assigned into two bleaching groups, white strip group treated with Crest® 3D WHITE™ LUXE Professional Effects Whitestrips (Proctor & Gamble, Greensboro, NC), and whitening toothpaste group, treated with Crest® 3D WHITE™ BRILLIANCE 2-Step Toothpaste (Proctor & Gamble, Greensboro, NC). The groups were further divided into 4 subgroups A, B, C, D (n=15 per group). Subgroups A and C were bonded 7 days after bleaching while subgoups B and D were bonded 24 hours after bleaching. Differences in shear bond strength between the subgroups and an unbleached control group (n=15) were compared using the Kruskal-Wallis test. Spectrophotometric color changes were recorded pre- and post-bleaching. ResultsThe mean shear bond strength for the white strip groups were 10.35±3.6 MPa and 11.69±4.33 MPa for the 7-day and 24-hour delayed bonding periods, respectively. Means for the whitening toothpaste groups were 11.01±4.31 MPa and 10.83±3.79 MPa for the 7-day and 24-hour delayed bonding periods. The mean for the control group was 9.59±3.32 MPa. There were no significant differences in shear bond strength between the groups at 7-days and 24-hour (P=0.650). There was a significant difference between teeth bleached with white strips as compared to those bleached with toothpaste and controls. The correlations between color change and shear bond strength were not significant (P=0.448). ConclusionsThere is a significant difference in the amount of whitening achieved by over-the-counter white strips compared to toothpaste; however, no significant effects on shear bond strength occurred after bleaching with white strips and toothpaste at 24-hours and 7-days. Key words:Bleaching, shear bond strength, orthodontics, over-the-counter.

Influence of topical fluoride on shear bond strength of orthodontic brackets and enamel white spot lesions formation

Abstract Introduction Fluoride is considered a key element in the remineralization process of tooth enamel. Objective To evaluate the influence of a topical solution of sodium fluoride (NaF) on the shear bond strength of orthodontic brackets and white spot lesions formation. Material and method Sixty bovine teeth were divided into three groups (n=20). Group 1 (Control): shear bond strength; Group 2: shear bond strength after pH cycling; Group 3: shear bond strength after pH cycling and treatment with 0.04% NaF solution. Groups 2 and 3 underwent pH cycling with demineralizing (6hs) and remineralizing (17hs) solutions at pH of 4.3 and 7.0 respectively for 15 days. The specimens were submitted to the shear bond strength and the Adhesive Remnant Index was verified (ARI). The specimens of each group (n=3) were qualitatively analyzed by means of Scanning Electron Microscopy (SEM). Kruskal-Wallis test assessed the shear bond strength and Fisher's exact test evaluated ARI, with significance level of 5%. Result There was no significant difference among the three groups in shear bond strength (p=0.2679). Significant difference was found in ARI (p=0.0199). The frequency of ARI 1 was 55% in group 1, 90% in group 2, and 80% in group 3. SEM showed difference between the enamel and bonding. Group 2 showed structural change of the enamel surface, adjacent to the bond area; and group 3 showed enamel with characteristics similar to those of group 1. Conclusion It was concluded that there was no NaF influence on the bracket shear bond strength and even in low concentrations it prevented the development of areas of demineralization of white spot lesions.

The Performance of Universal Adhesives on Orthodontic Bracket Bonding

Abstract Objective This article aimed to assess the effects of double application of universal adhesives on the shear bond strength of orthodontic brackets. Materials and Method Seventy-five extracted human premolars were used. The teeth were randomly assigned into five groups based on the adhesive procedure (n = 15). The universal adhesives Scotchbond Universal (3M Oral Care) and Prime&amp;Bond Universal (Dentsply) were used (following manufacturer’s instructions and double application). Transbond XT Primer (3M Unitek) was employed as control. Following adhesive application, the brackets were bonded on the tooth surfaces. After storage in distilled water for 24 hours at 37°C, the specimens were subjugated to the shear bond strength test under a universal testing machine (Autograph AGS-X; Shimadzu). Data were analyzed with one-way analysis of variance and least significant difference tests (p = 0.05). The adhesive remnant index (ARI) was determined using a stereomicroscope (S4E; Leica Microsystems). Data of ARI scores were submitted to Pearson’s chi-square test. Results The highest shear bond strengths were acquired with Scotchbond Universal (p &lt; 0.05). The double application of Scotchbond Universal did not impact the shear bond strength. The lowest shear bond strength was found in Prime&amp;Bond Universal (p &lt; 0.05). The double application of Prime&amp;Bond Universal increased the shear bond strength (p &lt; 0.05). There were no significant differences in ARI scores among the groups (p &gt; 0.05). Conclusion The universal adhesives may be an alternative for the bonding of orthodontic brackets. The double application of universal adhesives might improve the shear bond strength of orthodontic brackets depending on the material.

Adverse effect of consumption of carbonated soft drinks on orthodontic treatment - A systematic review.

The complications of soft drink consumption during orthodontic treatment includes degradation of enamel, reduction in the shear bond strength of orthodontic brackets, and also corrosion of orthodontic wires. The main objective of this review is to discuss the adverse effects of carbonated soft drink (CSD) consumption on patients undergoing fixed orthodontic treatment. A search of studies in MEDLINE (via PubMed), the Cochrane library, Web of science, IndMED, EMBASE, Google scholar and limited grey literature on the effects of consumption of CSDs was conducted. All pertinent abstracts were reviewed for inclusion. Full articles were retrieved for abstracts or titles that met the initial inclusion criteria or lacked sufficient detail for immediate exclusion. Out of the 4484 results obtained from search, 16 articles were selected based on title and 6 articles were eliminated after reading the abstracts. 10 articles were selected for systematic review which included 6 invitro studies, 1 animal study, 1 observational study and 2 invivo studies. Of these, six studies evaluated the effects of carbonated drinks on the shear bond strength of brackets on enamel of which two evaluated the microhardness of enamel, two studies evaluated the mechanical and chemical properties of wires, one evaluated tooth movement and one study focussed on white spot lesions. The results from the selected articles showed that with the consumption of carbonated drinks, there was reduced shear bond strength of orthodontic brackets, altered enamel characteristics, alteration of mechanical and physical properties of orthodontic wires and decrease in rate of orthodontic tooth movement. Based on the available evidence, CSD consumption during orthodontic treatment definitely has an effect on orthodontic appliances, enamel and possibly on tooth movement.

Efficacy of Three Enamel Protecting Agents on Shear Bond Strength of Orthodontic Brackets Bonded to Demineralised Enamel with Conventional Adhesive

Efficacy of Three Enamel Protecting Agents on Shear Bond Strength of Orthodontic Brackets Bonded to Demineralised Enamel with Conventional Adhesive

Performance of Different Orthodontic Brackets after Exposure to Dietary Components: An &amp;lt;i&amp;gt;in Vitro&amp;lt;/i&amp;gt; Pilot Study

Introduction: The aim of this study was to determine whether there was a significant difference in shear bond strength between metal and ceramic brackets when exposed to acidic dietary components (beverages) and to observe the chromogenic potential of each in vitro. Methods: Metal and clear orthodontic brackets were placed on extracted maxillary second premolars and exposed to select beverages three times daily for four weeks. Shade was taken using a colorimeter device at seven intervals and the shear bond strength of each bracket was recorded. Results: There was a variable change in tooth shade with respect to the various beverages in which they were submerged. Coffee and Dr. Pepper had the most pronounced change, whereas Red Bull and water produced little to none, respectively. Compared to controls, brackets submerged in coffee had the greatest reduction in shear bond strength, followed by Dr. Pepper, then Red Bull. Overall, clear brackets showed higher shear bond strength than metal brackets. Conclusion: Acidic dietary components have a negative effect on the shear bond strength of orthodontic brackets, and more pigmented beverages have a higher chromogenic staining potential.

Shear bond strength of orthodontic brackets using orthodontic and restorative self-etching primer. An in vitro study

Background and Aim: Self-etching primers (SEPs) are used to reduce the chair side time. However, there are different SEPs that are used in orthodontics. This study is aimed to test the shear bond strength of brackets bonded using SEPs used in restorative dentistry in comparison to orthodontic SEPs. Settings and Design: Department of Orthodontics, Post-graduate dental college, Council of Scientific and Industrial Research (CSIR) laboratory, in vitro study. Methods and Material: Seventy-five freshly extracted human maxillary first premolar teeth were used in this study. Orthodontic maxillary first premolar McLaughlin Bennett Trevisi (MBT) metal brackets (3M Unitek) were used to bond the teeth. The study consisted of two groups. Group A: 25 teeth were etched with Orthodontic SEP Transbond Plus (3M Unitek). Group B: Experimental group which is divided into two subgroups, Experimental subgroup a and Experimental subgroup b. Subgroup a: 25 teeth were etched with Restorative purpose SEP Adper SE Plus (3M ESPE). Sub group-b: 25 teeth were etched with Restorative purpose SEP Adper Easy One (3M ESPE). In all the groups, the same adhesive material, Transbond XT (3M Unitek) was used for fixing the brackets. All the 75 teeth were subjected to shear force to test shear bond strength by using Instron machine. Statistical Analysis: ANOVA & Scheffe multiple comparison test were used. Results and Conclusion: Shear bond strength of brackets using orthodontic purpose SEP, Transbond Plus, is more than the SEPs used for restorative purpose, i.e., Adper SE Plus and Adper Easy One. Restorative purpose SEPs are not suitable for orthodontic bonding of brackets. Orthodontic bonding, self-etching primer (SEP), shear bond strength (SBS)

The effect of surface treatment and thermocycling on the shear bond strength of orthodontic brackets to the Y-TZP zirconia ceramics: A systematic review

ABSTRACTIntroduction: Various surface pre-treatment methods have been adapted to optimize the bonding between the zirconia ceramics and the orthodontic brackets. Objective: This review is aimed at systematically analyzing the relevant data available in the literature, to find out the most effective and durable bonding protocol.Methods: Database search was conducted in PubMed, Scopus, and ScienceDirect, during September 2020. The review was conducted according to the PRISMA guidelines. Results: Based on the inclusion criteria, 19 articles were selected for qualitative analysis. Meta-analysis could not be performed due to the heterogeneity of the methodology among the studies. Most of the studies scored medium risk of bias. Compared to the untreated surface, surface pretreatments like sandblasting and lasers were advantageous. Primers and universal adhesive were mostly used as an adjunct to the mechanical pretreatment of the zirconia surface. In most studies, thermocycling seemed to lower the shear bond strength (SBS) of the orthodontic brackets.Conclusion: Based on this qualitative review, surface pretreatments with lasers and sandblasting can be suggested to optimize the bracket bond strength. To clarify this finding, meta-analysis is anticipated. Hence, high heterogeneity of the included studies demands standardization of the methodology.

The Effect of Topical Application of Strontium on Bond Strength in Orthodontics. (In Vitro Study)

Objective: to evaluate the effects of topical application of strontium on bond strength in orthodontics in vitro by using Instron universal testing machine . Materials and Methods: forty eight bovine enamel specimens were randomly allocated to four groups (n =12). Specimens of group I were not demineralized and were not pretreated, but served as controls. The other specimens were demineralized by using Featherstone pH cycling technique to form artificial carious lesions. Samples from group II were only demineralized. The other samples were pretreated with strontium chloride solution(Srcl2) for 5 minutes. Teeth in groups III were treated with Srcl2 solution before acid-etching. Teeth in groups IV were treated with Srcl2 after acid-etching. The brackets were then bonded .The brackets' SBS was measured and the adhesive remnant was assessed using adhesive remnant index (ARI). Analyses were done for SBS values between the four groups using One-Way ANOVA test followed by Post Hoc Tukey’s analysis between each two groups .Fisher’s exact test was used to evaluate differences in ARI scores between the groups. Results: srcl2treated group before acid etching )showed the highest mean SBS value when compared to other groups (Mean ± SD =24.7±7.4 MPa). There was insignificant difference between the four groups as regarding ARI scores (p=0.406). Conclusion: The topical application of srcl2 did not compromise the bond strength of orthodontic brackets to demineralized bovine enamel.

In Vitro Shear Bond Strength of Orthodontic Brackets after Enamel Conditioning with Acid Etching and Hydroabrasion.

The purpose of this study was to evaluate the shear bond strength and adhesive remnant index ARI) of orthodontic brackets following enamel conditioning with acid etching, hydroabrasion, and with both procedures. Thirty extracted human premolars were divided into three groups and received either acid etching, hydroabrasion or both procedures. Orthodontic brackets were bonded with composite resin. Shear bond strength was tested with a tensile machine, then the teeth were observed under a stereomicroscope to evaluate ARI scores. The enamel morphology after each conditioning method was evaluated with scanning electron microscope imaging. A one-way ANOVA and a Kruskal−Wallis H test were used to compare the bond strength and the ARI scores among the three groups. Hydroabrasion alone produced shear bond strength values below clinical acceptability, while the combination of acid etching and hydroabrasion produced the highest values. The ARI scores in the hydroabrasion group were significantly different from the other groups. Hydroabrasion followed by acid etching was effective in increasing the shear bond strength of orthodontic brackets. Further in vivo studies are needed to confirm the cost and benefits of this technique.

Evaluation of the bond strength of orthodontic brackets and the degree of polymerisation and microhardness of an orthodontic adhesive using polyvawe light curing unit and varying light densities

Objective: This study evaluates the shear bond strength (SBS) and Vickers micro-hardness (VHN) of the orthodontic adhesive resin Transbond XT using thermocycled samples. The study also measures the degree of cure by poliwave light curing unit Valo. Materials and Methods: 135 brackets were bonded for the SBS test, and 90 disc-shaped orthodontic adhesive resins were prepared for the VHN test. The measurements were taken either immediately or after 500 or 10.0000 thermocycling. The SBS and VHN test data were statistically evaluated using a Two-way ANOVA and Tukey multiple comparison tests. The degree of conversion (DC) was measured by FTIR. Results: The 10-sec polymerized control group (57.08) and the 10.000 termocycled samples (55.96) had the highest VHN scores. On the other hand, the 3 second polymerized and the 10.000 termocycled samples (39.22) had the lowest VHN scores. There was no significant difference in the bracket SBS values between the termocycled and immediate groups. An evaluation of the bond failure surfaces revealed that the ARI scores did not differ between the immediate and the thermo-cycled groups according to the power modes. The FTIR results revealed that the lowest DC was seen in the 3 second light-cured sample. Conclusion: Transbond XT provided sufficient bonding in terms of microhardness and DC under in vitro bracket bonding conditions after 10 and 8 seconds of Poliwave LED curing. However, low mean values were seen in the groups that received Poliwave LED curing for only 3 seconds. KEYWORDSARI score; FTIR; Light-Emitting Diode; Orthodontics; Thermocycling.

Does the antioxidant treatment affect the shear bond strength of orthodontic brackets: An in vitro study

Does the antioxidant treatment affect the shear bond strength of orthodontic brackets: An in vitro study

Shear Bond Strength of Orthodontic Brackets to Fluorosed Enamel; In-Vitro Study

Shear Bond Strength of Orthodontic Brackets to Fluorosed Enamel; In-Vitro Study

Shear Bond Strength of Orthodontic Brackets to Zirconium Oxide Infrastructure Treated with Er:YAG, Nd:YAG, and KTP Lasers: An Experimental Study

Objectives: The aim of the present study was to investigate the shear bond strength of orthodontic brackets to zirconium oxide infrastructures treated with erbium-doped yttrium aluminum garnet (Er:YAG), neodymium-doped yttrium aluminum garnet (Nd:YAG) and potassium titanyl phosphate (KTP) laser modalities in in vitro settings. Materials and Methods: A total of 40 zirconium oxide infrastructures were prepared with CAD/CAM technology in accordance with ISO 11405 standard. The specimens were divided into 4 groups as following: Er:YAG, Nd:YAG, KTP, and control groups (n=10). Prior to the application of cementation of orthodontic brackets, the surfaces of the zirconium oxide infrastructures were irradiated using selected laser modailites. Shear bond strength tests were performed on each specimen by using a universal testing machine. Results: The shear bond strength value of Er:YAG laser group was significantly higher than those of all other groups (p&amp;lt;0.05); although the bonding strength of Nd:YAG laser was higher than that of the KTP laser, this difference was not reached statistical significance (p&amp;gt;0.05). The bonding strength values of Nd:YAG laser group were significantly higher than that of the control group (p&amp;lt;0.05); and the the bonding strength values of KTP laser group were significantly higher than that of control group (p&amp;lt;0.05). Conclusion: The bond strength between the orthodontic brackets and zirconium oxide infrastructures was improved upon using all the laser modalities in the present study, among which, application of the Er:YAG laser was the most successful.