Effect of Yd:YAG laser irradiation on the shear bond strength of orthodontic metal brackets

ABSTRACT Objective: The purpose of this study was to evaluate the effect of the Yd:YAG laser irradiation on orthodontic bracket base surface. Shear bond strength (SBS) values and sites of the bonding failure interfaces were quantified. Methods: Brackets were divided into two groups: OP (One Piece - integral sandblast base) and OPL (One Piece - laser irradiation). The brackets were randomly bonded on an intact enamel surface of 40 bovine incisors. The SBS tests were carry out using a universal test machine. A stereomicroscopy was used to evaluate the adhesive remnant index (ARI), and surface characterization was performed by scanning electron microscopy (SEM). Student’s t-test was used to compare the SBS between the two groups (p< 0.05). Frequencies and chi-square analysis were applied to evaluate the ARI scores. Results: OPL group showed higher value (p< 0.001) of SBS than OP group (43.95 MPa and 34.81 MPa, respectively). ARI showed significant difference (p< 0.001) between OPL group (ARI 0 = 100%) and OP group (ARI 0 = 15%). SEM showed a higher affinity between the adhesive and the irradiated laser base surface. Conclusions: Yd:YAG laser irradiation on bracket base increased SBS values, showing that bonding failure occurs at the enamel/adhesive interface. Laser-etched bracket base may be used instead of conventional bases in cases where higher adhesion is required, reducing bracket-bonding failure.

Download Full-text

Etching Enamel for Orthodontics with an Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet Laser System

The Angle Orthodontist ◽

10.2319/120605-426r.1 ◽

2007 ◽

Vol 77 (1) ◽

pp. 117-124 ◽

Cited By ~ 47

Author(s):

Güvenç Basaran ◽

Törün Özer ◽

Nükhet Berk ◽

Orhan Hamamcı

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Shear Bond Strength ◽

Laser System ◽

Surface Characteristics ◽

Enamel Surface ◽

Acid Etching ◽

Adhesive Remnant Index ◽

Significant Difference ◽

Power Outputs

Abstract Objective: To test the shear bond strength, surface characteristics, and fracture mode of brackets that are bonded to enamel etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at different power outputs: 0.5 W, 1 W, and 2 W. Materials and Methods: Human premolars that had been extracted for orthodontic purposes were used. Enamel was etched with an Er,Cr:YSGG laser system operated at one of three power outputs or with orthophosphoric acid. Results: The shear bond strength associated with the 0.5-W laser irradiation was significantly less than the strengths obtained with the other irradiations. Both the 1-W and 2-W laser irradiations were capable of etching enamel in the same manner. This finding was confirmed by scanning electron microscopy examination. The evaluation of adhesive-remnant-index scores demonstrated no statistically significant difference in bond failure site among the groups, except for the 0.5-W laser–etched group. Generally, more adhesive was left on the enamel surface with laser irradiation than with acid etching. Conclusion: The mean shear bond strength and enamel surface etching obtained with an Er,Cr: YSGG laser (operated at 1 W or 2 W for 15 seconds) is comparable to that obtained with acid etching.

Download Full-text

Comparison of Shear Bond Strength of MIM Technology Brackets with Conventional and Rail-Shaped Mesh Bases: An In Vitro Study

The Open Dentistry Journal ◽

10.2174/1874210601913010255 ◽

2019 ◽

Vol 13 (1) ◽

pp. 255-260

Author(s):

Francisco Molina ◽

Karina Maria Salvatore Freitas ◽

Maria Cristina Rockenbach Binz Ordóñez ◽

Emerson Flamarion Cruz ◽

Rafael Pinelli Henriques ◽

...

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Dental Enamel ◽

In Vitro Study ◽

Metal Injection Molding ◽

Test Machine ◽

Intergroup Comparison ◽

Significant Difference ◽

Mim Technology

Objective: The objective of this study was to evaluate in vitro the shear bond strength of two types of MIM (Metal Injection Molding) technology brackets, one with conventional mesh base and the other with rail-shaped mesh base. Materials and Methods: Forty human premolars received the bonding of 2 types of brackets: Group 1- 20 Synergy metal brackets (Rocky Mountain) with conventional mesh base and Group 2-20 H4 brackets (OrthoClassic) with rail-shaped mesh base. Both brackets were bonded with Resilience photopolymerizable resin (OrthoTechnology). The specimens were coupled to a Tinius Olsen universal test machine where the shear test was performed using a chisel. In addition, the amount of remaining resin in tooth crown with the ImageJ program was evaluated and the Adhesive Remnant Index (ARI). Intergroup comparison was performed by the independent t test and Chi-square test. Results: There was no statistically significant difference between the groups for any of the measures evaluated indicating that the mesh type of the brackets’ base with MIM technology did not influence the shear bond strength of the brackets (shear bond strength, p=0.191; maximum load registered, p=0.244). There was also no difference between the percentage (p=0.602) and area of remaining resin in the teeth (p=0.805) and IRA (p=0.625) between the Synergy and H4 groups. Conclusion: Shear bond strength was similar in the two types of brackets with MIM technology evaluated. In addition, the remaining resin in the dental enamel of two types of brackets were also similar.

Download Full-text

Variations in orthodontic bracket retention related to base design. Comparison of foil mesh and anchor pylons brackets

Journal of Stomatology ◽

10.5604/00114553.1230589 ◽

2016 ◽

Vol 69 (6) ◽

pp. 680-695 ◽

Cited By ~ 1

Author(s):

Marta Gibas-Stanek ◽

Stephen Williams ◽

Wojciech I. Ryniewicz ◽

Bartłomiej W. Loster

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Testing Machine ◽

Orthodontic Bracket ◽

Significant Difference ◽

Bonding Properties ◽

Student’S T ◽

Plastic Brackets ◽

Bracket Base ◽

Base Design

Aim of the study. To compare the shear bond strength of metal brackets with foil mesh (3M, Victory Series), one piece metal brackets (Cannon Ultra) and aesthetic plastic brackets (Cannon Ultra) and to evaluate the sandblasting effect on previously used metal bracket bases regarding their bonding ability. Materials and Methods.A total of seventy human third molars were divided into four groups, and brackets were bonded to the enamel using Transbond XT. After 24 hours of storage, brackets were debonded with Instron Universal Testing Machine® and shear bond strength was recorded. Metal brackets were sandblasted until all visible bonding material was removed from the bracket base and then the bonding procedure and shear bond testing were repeated. Shapiro-Wilk test was used to check normal distribution. Student’s t-test was used to compare the shear bond strength. Results. The shear bond strength of one-piece metal brackets is significantly bigger (18.93MPa) than metal brackets with foil mesh (12.53MPa). Metal brackets in general demonstrate better bonding properties than aesthetic plastic brackets (8.61MPa). There is no statistically significant difference in shear bond strength between new and re-used sandblasted brackets. Conclusions. One-piece brackets with anchor pylons demonstrate better bonding properties but there is a higher risk of enamel damage during debonding of re-used sandblasted brackets.

Download Full-text

Simplified Surface Treatments for Ceramic Cementation: Use of Universal Adhesive and Self-Etching Ceramic Primer

International Journal of Biomaterials ◽

10.1155/2018/2598073 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Heloísa A. B. Guimarães ◽

Paula C. Cardoso ◽

Rafael A. Decurcio ◽

Lúcio J. E. Monteiro ◽

Letícia N. de Almeida ◽

...

Keyword(s):

Bond Strength ◽

Surface Treatment ◽

Hydrofluoric Acid ◽

Shear Bond Strength ◽

Strength Test ◽

Surface Treatments ◽

Resin Cement ◽

Test Machine ◽

Universal Adhesive ◽

Significant Difference

The aim of this study was to evaluate the shear bond strength of resin cement and lithium disilicate ceramic after various surface treatments of the ceramic. Sixty blocks of ceramic (IPS e.max Press, Ivoclar Vivadent) were obtained. After cleaning, they were placed in polyvinyl chloride tubes with acrylic resin. The blocks were divided into six groups (n=10) depending on surface treatment: H/S/A - 10% Hydrofluoric Acid + Silane + Adhesive, H/S -10% Hydrofluoric Acid + Silane, H/S/UA - 10% Hydrofluoric Acid + Silane + Universal Adhesive, H/UA- 10% Hydrofluoric Acid + Universal Adhesive, MBEP/A - Monobond Etch & Prime + Adhesive, and MBEP - Monobond Etch & Prime. The light-cured resin cement (Variolink Esthetic LC, Ivoclar Vivadent) was inserted in a mold placed over the treated area of the ceramics and photocured with an LED for 20 s to produce cylinders (3 mm x 3 mm). The samples were subjected to a shear bond strength test in a universal test machine (Instron 5965) by 0.5 mm/min. ANOVA and Tukey tests showed a statistically significant difference between groups (p<0.05). The results of the shear strength test were H/S/A (9.61±2.50)A, H/S (10.22±3.28)A, H/S/UA (7.39±2.02)ABC, H/UA (4.28±1.32)C, MBEP/A (9.01±1.97)AB, and MBEP (6.18±2.75)BC. The H/S group showed cohesive failures, and the H/UA group was the only one that presented adhesive failures. The conventional treatment with hydrofluoric acid and silane showed the best bond strength. The use of a new ceramic primer associated with adhesive bonding obtained similar results to conventional surface treatment, being a satisfactory alternative to replace the use of hydrofluoric acid.

Download Full-text

Influence of hydrofluoric acid etching time and concentration on shear bond strength of metal brackets to ceramic surfaces

Revista de Odontologia da UNESP ◽

10.1590/1807-2577.10219 ◽

2019 ◽

Vol 48 ◽

Author(s):

Cedirlei Gomes da Silveira ANDRADE ◽

Diego Patrik Alves CARNEIRO ◽

Mariana NABARRETTE ◽

Américo Bortolazzo CORRER ◽

Heloisa Cristina VALDRIGHI

Keyword(s):

Bond Strength ◽

Hydrofluoric Acid ◽

Shear Bond Strength ◽

Resin Composite ◽

Acid Etching ◽

Etching Time ◽

Time Interval ◽

Test Machine ◽

Ceramic Surface ◽

Significant Difference

Abstract Introduction Surface treatment prior to bonding ceramic brackets with hydrofluoric acid is indicated because of its ability to promote morphological changes necessary for adhesion. Objective To evaluate the shear bond strength (RUC) of metal brackets bonded to the feldspar ceramic surface under the action of hydrofluoric acid (AF), in different concentrations (5% and 10%) and different application times (30 and 60 seconds). Material and method Four nickel-chrome metal blocks that received an application of feldspathic ceramic were used, to which 80 metal brackets (Abzil/3M) were bonded and divided into 4 Groups (n=20) according to the acid etching procedure. The blocks were etched with 5% hydrofluoric acid for 30 and 60 seconds (AF5/30 and AF5/60, respectively) and 10% hydrofluoric acid for 30 and 60 seconds (AF10/30, AF10/60, respectively). The resin composite used was Transbond XT (3M) and the presence of a glazer was maintained on the ceramic surface. The specimens were placed on a Universal test machine Instron 4411 (Instron Corp, USA) to which a chisel was adapted to perform the shear test at a speed of 1mm/min. The data were submitted to the analysis of variance (ANOVA) and the Adhesive Remnant Index was evaluated. Result In the time interval of 30 seconds, there was no significant difference for the 5% and 10% hydrofluoric acid concentrations. In the 60-second time interval, the 10% concentration showed significantly higher shear bond strength values (p<0.05). The ARI showed predominance of scores 1 and 2. Conclusion It was concluded that 10% hydrofluoric acid showed higher shear bond strength values in 60 seconds of etching, while 5% hydrofluoric acid showed no significant difference between the etching times.

Download Full-text

The Effect of Different Bracket Base Cleaning Method on Shear Bond Strength of Rebonded Brackets

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1417 ◽

2013 ◽

Vol 14 (5) ◽

pp. 866-870 ◽

Cited By ~ 1

Author(s):

Emad F Al Maaitah ◽

Sawsan Alomari ◽

Elham S Abu Alhaija ◽

Ahmed AM Saf

Keyword(s):

Bond Strength ◽

Failure Mode ◽

Shear Bond Strength ◽

Control Group ◽

Slow Speed ◽

Cleaning Method ◽

Adhesive Remnant Index ◽

Random Samples ◽

Significant Difference ◽

Bracket Base

ABSTRACT Aim To assess the effect of different bracket base conditioning method on shear bond strength (SBS) of rebonded brackets. Materials and methods Eighty brackets were bonded to freshly extracted premolar teeth using light cured composite adhesive. SBS was measured for 20 random samples as control group (G1). After debonding, 60 debonded brackets were allocated randomly into three groups of bracket base conditioning methods to remove the remaining adhesives. G2: bracket base cleaned with slow speed round carbide bur (CB), G3: cleaned with ultrasonic scaler (US), G4: cleaned with sandblasting (SB). After that, brackets were rebonded in the same manner as first bonding and SBS was measured. Modified adhesive remnant index (ARI) was recorded for all groups. Results SBS for new brackets was 11.95 MPa followed by 11.65 MPa for G2, 11.56 MPa for G4 and 11.04 MPa for G3 group. There were no statistically significant differences between all groups (p = 0.946). In all groups, failure mode showed that the majority of adhesive composite remained on the bracket base with ARI of 4. There was no statistically significant difference between all groups in ARI (p = 0.584). Conclusion In-office methods; slow speed CB and US are effective, quick and cheap methods for bracket base cleaning for rebonding. How to cite this article Al Maaitah EF, Alomari S, Alhaija ESA, Safi AAM. The Effect of Different Bracket Base Cleaning Method on Shear Bond Strength of Rebonded Brackets. J Contemp Dent Pract 2013;14(5):866-870.

Download Full-text

Effect of Different Surface Treatments for Ceramic Bracket Base on Bond Strength of Rebonded Brackets

Brazilian Dental Journal ◽

10.1590/0103-6440201300234 ◽

2015 ◽

Vol 26 (1) ◽

pp. 61-65 ◽

Cited By ~ 3

Author(s):

Monique Kruger Guarita ◽

Alexa Helena Köhler Moresca ◽

Estela Maris Losso ◽

Alexandre Moro ◽

Ricardo Cesar Moresca ◽

...

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Silica Coating ◽

Surface Treatments ◽

Enamel Surface ◽

Control Group ◽

Significant Difference ◽

Ceramic Brackets ◽

Ceramic Bracket ◽

Bracket Base

The aim of this study was to evaluate the shear bond strength of rebonded ceramic brackets after subjecting the bracket base to different treatments. Seventy-five premolars were selected and randomly distributed into five groups (n=15), according to the type of the bracket surface treatment: I, no treatment, first bonding (control); II, sandblasting with aluminum oxide; III, sandblasting + silane; IV, silica coating + silane; and V, silicatization performed in a laboratory (Rocatec system). The brackets were fixed on an enamel surface with Transbond XT resin without acid etching. The brackets were then removed and their bases were subjected to different treatments. Thereafter, the brackets were fixed again to the enamel surface and the specimens were subjected to shear bond strength (SBS) test. The adhesive remnant index (ARI) was then evaluated for each specimen. Data were subjected to ANOVA and Tukey's tests (α=0.05). A statistically significant difference was observed only between Rocatec and the other groups; the Rocatec group showed the lowest SBS values. The highest SBS values were observed for group 1, without any significant difference from the values for groups II, III and IV. Most groups had a higher percentage of failures at the enamel-resin interface (score 1). It was concluded that the surface treatments of rebonded ceramic brackets were effective, with SBS values similar to that of the control group, except Rocatec group.

Download Full-text

Comparison between Shear Bond Strength of Er:YAG and Er,Cr:YSGG Lasers-Assisted Dentinal Adhesion of Self-Adhering Resin Composite: An Ex Vivo Study

Dentistry Journal ◽

10.3390/dj8030066 ◽

2020 ◽

Vol 8 (3) ◽

pp. 66

Author(s):

Paul Nahas ◽

Samir Nammour ◽

Elie Gerges ◽

Toni Zeinoun

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Shear Bond Strength ◽

Resin Composite ◽

Control Group ◽

Tooth Structure ◽

Resin Infiltration ◽

Significant Difference ◽

Group 2 ◽

Group 1

(1) Background: Bonding composite to tooth structure is still evolving with a substitute for phosphoric acid being the main challenge. Lately, a self-adhering composite (SAC) was developed, promising to simplify bonding to tooth structure. Unfortunately, retention especially to dentin, was not as good as the gold standard three steps bonding system. During the last 2 decades, lasers were used to enhance shear bond strength of composite to tooth structure. However, the literature provided limited information regarding laser efficiency in the immediate, as well as the long term, adhesion success of SACs to dentin. The purpose of our study was to define the optimal irradiation conditions to improve the adhesion of self-adhering flowable resin composite to dentin exposed to Er:YAG and Er,Cr:YSGG laser irradiation. (2) Methods: Seventy-two freshly extracted human third molars, prepared to have flat dentinal surfaces, were randomly divided into three groups (n = 24) including a control group (Group 1) in which dentin was left without laser irradiation. The other two groups (Group 2 and 3) received standardized irradiation at a speed of 1 mm/second with Er:YAG (60 mJ; SSP mode = 50 μs; 10 Hz; fluency of 9.4 J/cm2; beam diameter: 0.9 mm; air 6 mL/min; and water 4 mL/min), and Er,Cr:YSGG: 1.5 W; fluency of 17.8 J/cm2; turbo handpiece with MX5 short insert; 20 Hz under air/water spray (65% air, 55% water). Self-adhering flowable resin was applied to dentin in all groups. Half of the specimens were stored in water for 24 h while the other half underwent 3000 thermal cycles. Later, all specimens received a shear bond strength test. Fracture observation was done first under a stereomicroscope then by using a scanning electron microscope. (3) Results: The mean values of shear bond strength for both laser-treated dentin groups (Er:YAG laser: 13.10 ± 1.291, and Er,Cr:YSGG: 14.04 ± 5.233) were higher than in the control group 1 (8.355 ± 2.297) before thermocycling. After thermocycling, shear bond strength decreased in all groups as follows: 10.03 ± 1.503, 10.53 ± 2.631, and 02.75 ± 1.583 for Er:YAG, Er,Cr:YSGG, and nonirradiated dentin, respectively. Shear bond strength values showed a significant difference between the control group (Group 1) and both lasers groups (Group 2 and 3). Statistical analysis of stereomicroscope observation revealed no significant difference between laser irradiation and failure mode (p < 0.136). SEM observation of the dentin surface in both laser-irradiated groups showed opened tubules, absence of smear layer as well as an increase of resin infiltration into dentinal tubules. (4) Conclusion: Er:YAG and Er,Cr:YSGG lasers enhance self-adhering flowable resin shear bond strength values and improve its longevity by eliminating the smear layer, opening dentinal tubules and increasing resin infiltration into the microstructure.

Download Full-text

The Effect of Remineralizing Agents With/Without CO2 Laser Irradiation on Structural and Mechanical Properties of Enamel and its Shear Bond Strength to Orthodontic Brackets

Journal of lasers in medical sciences ◽

10.34172/jlms.2020.25 ◽

2020 ◽

Vol 11 (2) ◽

pp. 144-152

Author(s):

Hannaneh Ghadirian ◽

Allahyar Geramy ◽

Waleed Shallal ◽

Soolmaz Heidari ◽

Nooshin Noshiri ◽

...

Keyword(s):

Mechanical Properties ◽

Bond Strength ◽

Laser Irradiation ◽

Co2 Laser ◽

Shear Bond Strength ◽

Testing Machine ◽

Orthodontic Brackets ◽

Beam Diameter ◽

Demineralized Enamel ◽

Significant Difference

Introduction: Remineralizing agents may be used for the treatment of white spot lesions (WSLs) prior to bracket bonding. However, some concerns exist regarding their possible interference with the etching and bonding process, negatively affecting the bond strength. This study aimed to assess the effect of two remineralizing agents with/without CO2 laser irradiation on the mechanical properties and shear bond strength (SBS) of demineralized enamel to the orthodontic bracket. Methods: This study evaluated 60 premolar teeth in 6 groups (n=10) as follows: (I) sound enamel, (II) demineralized enamel, (III) Nupro remineralizing agent (N), (IV) Nupro and CO2 laser (N/L), (V) Teethmate remineralizing agent (T), and (VI) Teethmate and CO2 laser (T/L). The remineralizing agents were applied to the enamel surfaces after their immersion in a demineralizing solution for 5 days. In groups IV and VI, the CO2 laser with a 10.6 μm wavelength, 10 ms pulse duration, a 50 Hz repetition rate, 0.3 mm beam diameter and 0.7 W power was irradiated after applying the remineralizing agents. Brackets were bonded to the enamel surfaces and SBS was measured by a universal testing machine. For the assessment of enamel microhardness, 20 sections of molar teeth were divided into 4 groups (n=5; N, N/L, T, T/L) and their microhardness was measured before demineralization, after demineralization and after remineralization. X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FESEM) and energy-dispersive spectrometry (EDS) were carried out to assess the formation of hydroxyapatite. The atomic percentages of the C, O, P, Ca, Na, Si, F and Ca/P ratio were determined by EDS analysis. Results: The SBS significantly decreased in group II (P<0.001). There was no significant difference among the groups I, III, IV, V and VI (P<0.05). This finding was similar to the microhardness results, which showed an increase in microhardness after remineralization (P<0.05), with no difference among the remineralizing agents. The Ca/P ratio was the highest in the Nupro group and the lowest in the demineralized group. Conclusion: Remineralizing agents can significantly improve the microhardness and structural properties of demineralized enamel to a level similar to that of sound enamel with no adverse effect on SBS to orthodontic brackets.

Download Full-text

In Vitro Study of Shear Bond Strength in Direct and Indirect Bonding with Three Types of Adhesive Systems

Materials ◽

10.3390/ma13112644 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2644

Author(s):

Angelica Iglesias ◽

Teresa Flores ◽

Javier Moyano ◽

Montserrat Artés ◽

Francisco Javier Gil ◽

...

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Acid Etching ◽

Test Machine ◽

Adhesive Systems ◽

Indirect Bonding ◽

Direct Technique ◽

Significant Difference

This study aimed to compare the shear bond strength (SBS) and adhesive remaining index (ARI) using one conventional and two novel adhesive systems with clinical step reduction and direct and indirect bonding. A sample of 72 human premolars were divided into six groups of 12 samples. The first three groups (G1, G2, G3) were bonded with a direct technique, while the remaining groups (G4, G5, G6) were bonded by the indirect technique. Groups G1 and G4 used conventional acid-etching primer composite (XT); groups G2 and G5 used self-etching bonding (BO), and groups G3 and G6 had an acid-etching treatment followed by a self-adhesive composite (OC). All groups were exposed to thermocycling. Shear bond strength was analyzed with a universal test machine, and the ARI was examined with 4× magnification. The results showed statistically significant differences between the three adhesive systems. The highest strength values were observed in the XT group G1 (13.54 ± 4 MPa), while the lowest were shown in the BO G2 samples (5.05 ± 2 MPa). There was no significant difference between the direct or indirect bonding techniques on the three compared groups. The type of primer and bonding material significantly influenced the SBS. Values with self-etching bonding were below the minimum recommended for clinical use (5.9–7.8 MPa). There was no difference between indirect and direct bonding techniques. The lowest ARI scores (0–1) were observed in both self-etching and BO groups. Further clinical studies are needed to compare in vivo results.

Download Full-text