Bond Strength Of Ceramic Brackets Research Articles

Influence of adhesive and thermal cycling on the bond strength of ceramic brackets to dental ceramic

Aim: This in vitro study investigated the effect of the application of an adhesive, silane and thermal cycling (TC) on the shear bond strength (SBS) of ceramic brackets to feldspathic ceramic. Methods: 16 cylinders of feldspathic ceramic were etched with hydrofluoric acid and divided into four groups (n=4): G1 - silane, without TC; G2 – silane, with TC; G3 - adhesive, without TC; G4 - adhesive, with TC. One layer of silane was applied on the surface of cylinders in G1 and G2 e one layer of photo-activated adhesive Single Bond Universal was used in G3 and G4. Ceramic brackets were bonded using Transbond XT. The SBS data were subjected to two-way ANOVA and Tukey’s post hoc test (α=0.05). The Adhesive Remnant Index (ARI) was evaluated at 40× magnification. Results: Silane was more effective than adhesive on the SBS of the brackets to ceramic (p<0.05). TC decreased significantly the SBS values compared with the groups without TC (p<0.05). The ARI results showed predominance of score 0. Conclusions: Groups with silane showed higher SBS than groups with adhesive. TC influence significantly on the bond strength. Regarding ARI, score 0 predominated in all groups.

Effect of different intracoronal bleaching methods on shear bond strength of ceramic brackets bonded to bleached enamel: An in-vitro study.

OBJECTIVE:To investigate the effect of different intracoronal bleaching methods on the shear bond strength and site of failure of ceramic brackets.MATERIALS AND METHODS:Sixty freshly extracted human maxillary incisors were randomly divided into four groups (n = 15). Endodontic access cavity was prepared and root canals were filled, root fillings were removed 2mm apical to the cementoenamel junction, and a 2-mmthick layer of glass ionomer cement base was applied. Group 1 served as the control. Intracoronal bleaching was performed with 35% carbamide peroxide in group 2, sodium perborate in group 3, and 37.5% hydrogen peroxide in group 4. The teeth were immersed in artificial saliva for 4 weeks before bracket bonding. Ceramic brackets were bonded with composite resin and cured with LED light. After bonding, the shear bond strength of the brackets was tested with a universal testing machine. The site of bond failure was determined by modified ARI (Adhesive Remnant Index).RESULTS:The highest value of shear bond strength was measured in control group (18.67 ± 1.59 MPa), which was statistically significant from groups 2,3, and 4. There was no significant difference between groups 2 and 4. The lowest shear bond strength was measured in group 3. ARI scores were not significant from each other.CONCLUSIONS:Intracoronal bleaching significantly affected the shear bond strength of ceramic brackets even after 4 weeks of bleaching. Bleaching with sodium perborate affects shear bond strength more adversely than does bleaching with other agents like hydrogen peroxide and carbamide peroxide.

COMPARISON OF SHEAR BOND STRENGTH OF METAL AND CERAMIC ORTHODONTIC BRACKETS AFTER ADDING NANOPARTICLES OF SILVER

Objective: To evaluate effect of nanoparticles of silver (NAg) added on Nano-Bond adhesive system and its effect on shear bond strength of brackets attached to enamel. Materials and methods: Thirty extracted premolar teeth for orthodontic reasons were divided into two groups; First group metal brackets and second group the ceramic brackets were bonded by Nano-Bond adhesive system containing (NAg) with concentration 0.05%. Every group was further subdivided into 2subgroups with 5 teeth each; Groups A1, B1 (Teeth not subjected to thermocycling and cyclic loading), Groups A2, B2 [(Teeth subjected to thermocycling (500cycles) and cyclic loading (90N, 0.8-1 cycles/sec. 100,000 cycles)]Enamel etched then the adhesives were applied to the entire enamel surface according to bonding agent containing (NAg) or not, then light cured for 10 seconds with LED. The base of brackets were filled by nano-filled composite resin and placed on the tooth and cured by LED for 40 seconds. The recorded values of bond strengths in (MPa) were collected, tabulated and statistically analyzed. One way analysis of variance (ANOVA) and Tukey’s tests were used for testing the significance between the means of tested groups which are statistically significant when the P value ≤ 0.05.Results: shear bond strength of metal brackets bonded by Nano-Bond adhesive containing nanoparticles of silver (NAg) (Group A) was significantly higher than shear bond strength of ceramic brackets (group B).Conclusions: The adhesive shear strengths are high for metal bracket bonded by Nano-Bond adhesive system containing nanoparticles of silver (NAg) with concentration 0.05% than ceramic bracket.

Effects of silane application on the shear bond strength of ceramic orthodontic brackets to enamel surface

Background: Fixed orthodontic appliances with ceramic brackets are used frequently to fulfill the aesthetic demand of patient through orthodontic treatment. Ceramic brackets have some weaknesses such as bond strength and enamel surface damage. In high bond strength the risk of damage in enamel surfaces increases after debonding. Purpose: This study aimed to determine the effect of silane on base of bracket and adhesive to shear bond strength and enamel structure of ceramic bracket. Method: Sixteen extracted upper premolars were randomly divided into four groups based on silane or no silane on the bracket base and on the adhesive surface. Design of the base on ceramic bracket in this research was microcrystalline to manage the influence of mechanical interlocking. Samples were tested in shear mode on a universal testing machine after attachment. Following it, adhesive remnant index (ARI) scores were used to assess bond failure site. Statistical analysis was performed using a two-way Anova and the Mann-Whitney test. A scanning electron microscope (SEM) with a magnification of 2000x was used to observe enamel structure after debonding. Result: Shear bond strength was increased between group without silane and group with silane on the base of bracket (p<0,05). There was no significance different between group without silane and group with silane on adhesive (p<0,05). Conclusion: Application of silane on base of bracket increases shear bond strength, however, application of silane on adhesive site does not increase shear bond strength of ceramic bracket. Most bonding failure occurred at the enamel adhesive interface and damage occurred on enamel structure in group contains silane of ceramic bracket.

Comparison of Shear Bond Strength of Ceramic Brackets Bonded To Ceramic Surface - An In-Vitro Study

Comparison of Shear Bond Strength of Ceramic Brackets Bonded To Ceramic Surface - An In-Vitro Study

Shear Bond Strength of Ceramic Brackets with Different Base Designs: Comparative In-vitro Study.

Knowledge about the Shear Bond Strength (SBS) of ceramic brackets with different base design is essential as it affects bond strength to enamel. The aim of the present study was to evaluate and compare the effect of base designs of different ceramic brackets on SBS, and to determine the fracture site after debonding. Four groups of ceramic brackets and one group of metal brackets with different base designs were used. Adhesive precoated base of Clarity Advanced (APC Flash-free) (Unitek/3M, Monrovia, California), microcrystalline base of Clarity Advanced (Unitek/3M, Monrovia, California), polymer mesh base of InVu (TP Orthodontics, Inc., La Porte, IN, United States), patented bead ball base of Inspire Ice (Ormco, Glendora, California), and a mechanical mesh base of Gemini Metal bracket (Unitek/3M, Monrovia, California). Ten brackets of each type were bonded to 50 maxillary premolars with Transbond XT (Unitek/3M). Samples were stored in distilled water at room temperature for 24 hours and subsequently tested in shear mode on a universal testing machine (Model 3382; Instron Corp., Canton, Massachusetts, USA) at a cross head speed of 1mm/minute with the help of a chisel. The debonded interface was recorded and analyzed to determine the predominant bond failure site under an optical microscope (Stereomicroscope) at 10X magnification. One way analysis of variance (ANOVA) was used to compare SBS. Tukey's significant differences tests were used for post-hoc comparisons. The Adhesive Remnant Index (ARI) scores were compared by chi-square test. Mean SBS of microcrystalline base (27.26±1.73), was the highest followed by bead ball base (23.45±5.09), adhesive precoated base (20.13±5.20), polymer mesh base (17.54±1.91), and mechanical mesh base (17.50±2.41) the least. Comparing the frequency (%) of ARI Score among the groups, chi-square test showed significantly different ARI scores among the groups (χ2 = 34.07, p<0.001). Different base designs of metal and ceramic brackets influence SBS to enamel and all were clinically acceptable.

SHEAR BOND STRENGTH OF ORTHODONTIC BRACKETS BETWEEN HEALTHY AND MILD FLUOROSED ENAMEL

Objective: To evaluate the influence of dental fluorosis on the shear bond strengths of orthodontic brackets bonded to enamel. Materials and methods: Twenty extracted human maxillary central incisors, extracted for periodontal reasons were used. The sample was divided into two experimental groups. Group A with healthy teeth and group B with mild fluorosed teeth. Etching enamel then the adhesives were applied to entire enamel surface then light cured for 10 seconds with LED. The base ceramic orthodontic brackets were filled by nano-filled composite and placed on the tooth and cured by LED for 40 seconds. The specimens were then thermocycled (5–55˚C, 500 cycles) and tested in Lloyd universal testing machine. The recorded values of bond strengths in (MPa) were collected, tabulated and statistically analyzed. One way analysis of variance (ANOVA) and Tukey’s tests were used for testing the significance between the means of tested groups which are statistically significant when the P value ≤ 0.05. Results: The mean shear bond strength of ceramic brackets bonded to non-fluorosed enamel (Group A) was significantly higher than shear bond strength of ceramic brackets bonded to fluorosed enamel (group B).

Shear Bond Strength of Ceramic Brackets with Different Base Designs: An in-vitro Study

Objective: To evaluate the influence of bracket base designs on shear bond strength of ceramic brackets bonded to natural teeth and to determine the common site of bond failure.Materials &amp; Method: 120 therapeutically extracted maxillary first premolars were divided into six groups of 20 samples each and were mounted in resin blocks. Each sample was bonded with bracket of that particular group and subjected to thermocycling. The shear bond strength was measured using Universal Testing Machine. After debonding, the teeth and brackets were examined under stereo-microscope for adhesive remnant index.Result: Ceramic brackets with ball base design (Group A) yielded statistically highest shear bond strength followed by microcrystalline base (Group D), dimple base (Group E), mesh base (Group C) and dove tail base (Group B) design. Ceramic brackets yield higher bond strength than metal brackets (Group F) irrespective of base design. Insignificant difference was seen between Group A and Group D and between Group B and Group C. Bond failure between adhesive and bracket (Type 3) was seen in 80% of the brackets with ball base design and bond failure between adhesive and bracket (Type 1) was seen in 80% of brackets with dove tail base design.Conclusion: Bracket base design is an important consideration for shear bond strength. Base design with more number of undercuts offer higher shear bond strength. Ceramic brackets with more number of mechanical undercuts were less likely to bond failure at adhesive bracket base interface and vice versa

Shear bond strength of ceramic brackets after different pre-treatments in porcelain surface

Shear bond strength of ceramic brackets after different pre-treatments in porcelain surface

Shear bond strength of ceramic brackets after different pre-treatments in porcelain surface

AIM: To evaluate the bond strength of brackets bonded after different surface treatments on two dental ceramics. METHODS: One hundred and twenty discs 5 mm thick and 7 mm diameter of two ceramic types were made and randomly divided in 8 groups. Groups 1, 3, 5, and 7 used Eris ceramic and groups 2, 4, 6, and 8 used d.Sign ceramic. The ceramic surfaces were treated with 10% hydrofluoric acid G1 and G2, 10% hydrofluoric acid + silane G3 and G4, aluminum oxide blasting + 35% phosphoric acid + silane G5 and G6, CoJet blasting + 35% phosphoric acid + silane G7 and G8. Metallic brackets were cemented with Concise cement. Mechanical test was performed in a universal testing machine until failure. RESULTS: The average values MPa obtained G1 - 7.30; G2 - 6.12; G3 - 17.49; G4 - 19.54; G5 - 18.80; G6 - 21.93; G7 - 6.81 e G8 - 9.77 were submitted to ANOVA and Tukey test p<0.05. The fracture patterns were analyzed in stereoscopic microscope 25´X and representative samples of each group were analyzed in SEM. CONCLUSIONS: It was possible to conclude that use of silane after hydrofluoric acid increased the bond strength values.

Shear bond strength of ceramic brackets bonded to three different porcelain surfaces

Introduction: The aim of this study is to determine the shear bond strength (SBS) of ceramic brackets bonded to three different porcelain surfaces. Materials and Methods: A total of 36 porcelain crowns were used in this study. Porcelain crowns were allocated to the three groups as follows: Conventional porcelain-fused-to-metal crowns, IPS e.max ceramic crowns, and porcelain-fused-to-zirconia crowns. Porcelain surfaces were etched with 9.6% hydrofluoric acid and rinsed with a water/spray combination. Then, ceramic brackets were bonded with a light-cured composite resin. All the specimens were stored in distilled water at 37°C for 24 hours and thermocycled and loaded into a universal testing machine for testing. Any adhesive that remained after debonding was assessed and scored according to the modified adhesive remnant index (ARI). Statistical Analysis: One-way analysis of variance (ANOVA) and Tukey's test were used to compare the SBS of the groups. The Chi-square test was used to determine the ARI scores among the groups. Results: No statistically significant difference between the ARI scores for the three types of crowns was observed. In the conventional porcelain-fused-to-metal crown group (7.09 MPa), the lowest values of bond strength were obtained. Although similar values of bond strength were found in the IPS e.max ceramic crown (8.60 MPa) and porcelain-fused-to-zirconia crown (8.93 MPa) groups, the statistically significant differences in values of shear bond strength have observed between the other groups. Conclusions: SBS of ceramic brackets bonded to different porcelain surfaces may produce different results due to the type of porcelain crown.

Effect of a DPSS laser on the shear bond strength of ceramic brackets with different base designs

This study evaluated the shear bond strength (SBS) and adhesive remnant index (ARI) of ceramic brackets with different base designs using a 473-nm diode-pumped solid-state (DPSS) laser to test its usefulness as a light source. A total of 180 caries-free human premolars were divided into four groups according to the base designs: microcrystalline, crystalline particle (CP), dovetail, and mesh. For each base design, teeth were divided into three different subgroups for light curing using three different light-curing units (LCUs) (quartz-tungsten-halogen unit, light-emitting diode unit, and a DPSS laser of 473 nm). Applied light intensities for the DPSS laser and the other LCUs were approximately 630 and 900 mW/cm(2), respectively. Stainless steel brackets with a mesh design served as controls. The failure modes of debonded brackets were scored using ARI. As a result, brackets bonded using the DPSS laser had the highest SBS values (16.5-27.3 MPa) among the LCUs regardless of base design. Regarding base designs, the CP groups showed the highest SBS values (22.9-27.3 MPa) regardless of LCU. Furthermore, stainless steel brackets with a mesh design had the lowest SBS values regardless of LCU. In many cases, brackets bonded using the DPSS laser had higher ARI scores and had more adhesive on their bases than on tooth surfaces. The study shows that the 473-nm DPSS laser has considerable potential for bonding ceramic brackets at lower light intensities than the other light-curing units examined.

Influence of ceramic surface treatment on shear bond strength of ceramic brackets

To compare four different surface treatment methods and determine which produces adequate bond strength between ceramic brackets and facets of porcelain (feldspathic), and evaluate the Adhesive Remnant Index (ARI) scores. Ten facets of porcelain specimens with glazed surfaces were used for each group. The specimens were randomly assigned to one of the following treatment conditions of the porcelain surface: (1) no surface treatment (control group), (2) fine diamond bur + orthophosphoric acid gel 37%, (3) hydrofluoric acid (HFL) 10%, and (4) HFL 10% + silane. Ceramic brackets were bonded with the adhesive cement Transbond XT. The shear bond strength values were measured on a universal testing machine at a crosshead speed of 0.5 mm/min. There was a significant difference (P<0.05) between the control group and all other groups. There was no significant difference (P<0.05) between treated porcelain surface with diamond bur + orthophosphoric acid gel 37% (4.8 MPa) and HFL 10% (6.1 MPa), but the group treated with HFL 10% had clinically acceptable bond strength values. The group treated with HFL 10% + silane (17.5 MPa) resulted in a statistically significant higher tensile bond strength (P<0.05). In group 4, 20% of the porcelain facets displayed damage. Etching of the surface with HFL increased the bond strength values. Silane application was recommended to bond a ceramic bracket to the porcelain surface in order to achieve bond strengths that are clinically acceptable.

Shear bond strength of ceramic brackets bonded with antimicrobial monomer-containing self-etching primer

Shear bond strength of ceramic brackets bonded with antimicrobial monomer-containing self-etching primer

Bond strength of ceramic brackets bonded to enamel with amorphous calcium phosphate-containing orthodontic composite

The aim of this in vitro study was to compare the shear bond strength (SBS) and failure modes of a conventional resin-based composite with a recently developed amorphous calcium phosphate (ACP)-containing orthodontic composite system. Forty freshly extracted human maxillary premolar teeth were randomly divided into two equal groups. Conventional composite (group 1; Transbond-XT; 3M Unitek) and ACP-containing orthodontic composite (group 2; Aegis-Ortho; Harry J. Bosworth Co.) were used for bonding ceramic orthodontic brackets. The SBS of these brackets were measured and recorded in megapascals (MPa). Adhesive remnant index (ARI) scores were determined after bracket failure. Data were analysed with a Student's t-test for two independent variables and Pearson's chi-square tests. Statistical analysis showed that the bond strength of group 1 (mean: 36.7 +/- 6.8 MPa) was significantly higher than group 2 (mean: 24.2 +/- 5.4 MPa; P < 0.01). Although a greater percentage of the fractures were cohesive at the composite interface (Score 1 + Score 2 = 70 per cent in group 1 and 90 per cent in group 2), statistically significant differences were observed between the groups (P < 0.05). The ACP system is suitable for bonding ceramic orthodontic brackets due to the lower SBS values compared with conventional composite. The ACP-containing composite is recommended for use in clinical orthodontic practice in order to achieve lower decalcification scores under ceramic orthodontic brackets.

Shear bond strength of ceramic brackets with various base designs bonded to aluminous and fluorapatite ceramics

This study was conducted to evaluate the shear bond strength (SBS) of various ceramic bracket base designs bonded to glazed aluminous (Vitadur Alpha) and fluorapatite (IPS e.max Ceram) ceramics, to examine the mode of failure, and to determine the debonding characteristics of the brackets and the ceramic surfaces after bond failure. Forty ceramic discs (15 mm in diameter and 1.5 mm thick) of each ceramic were prepared and divided into four equal groups. Ten pieces of each group of different bracket bases (beads, Inspire Ice; large round pits, Crystalline IV; and irregular base, Clarity) and one group of stainless steel brackets (Optimesh XRT, control) were bonded to glazed ceramics under a 200 g load. All specimens were then subjected to SBS evaluation using a universal testing machine at a crosshead speed of 0.2 mm per minute. The data were analysed using analysis of variance and Tukey's test at a significance level of 0.05. The mode of failure was examined under a stereomicroscope. The results demonstrated that for Vitadur Alpha and IPS e.max Ceram, the highest SBS were found with Inspire Ice (25.1 +/- 2.6 and 24.9 +/- 2.1 MPa) and were significantly different than Crystalline IV (21.6 +/- 1.1 and 20.9 +/- 1.5 MPa), Clarity (19.6 +/- 1.5 and 19.3 +/- 2.3 MPa), and Optimesh XRT (14.9 +/- 1.3 and 15.3 +/- 2.2 MPa; P < 0.05). Inspire Ice and Crystalline IV had 100 per cent adhesive failure while Clarity and Optimesh XRT had combination failure. The various base designs gave different SBS, but the SBS of all base designs could withstand normal orthodontic force.

Shear Bond Strength of Ceramic Brackets with Different Base Designs to Feldspathic Porcelains

Shear Bond Strength of Ceramic Brackets with Different Base Designs to Feldspathic Porcelains

The effect of a light-emitting diode on shear bond strength of ceramic brackets bonded to feldspathic porcelain with different curing times

The aim of this study was to evaluate different curing times of a light-emitting diode (LED) unit on shear bond strength (SBS) of ceramic brackets bonded to feldspathic porcelain. Ceramic brackets were bonded with a light-cured adhesive to 96 feldspathic porcelain facets. Air-borne particle abrasion was performed using 25 mum aluminium trioxide (Al(2)O(3)) with an air abrasion device from a distance of approximately 10 mm at a pressure of 2.5 bars for 4 seconds, then the porcelain surfaces were etched with 9.6 per cent hydrofluoric acid for 2 minutes. After surface preparation of the porcelain specimens, silane was applied. In groups 1 and 2, the adhesive was cured with a quartz-tungsten-halogen (QTH) unit for 10 and 20 seconds, respectively. The LED was used in the standard mode for 3, 5, and 10 seconds for groups 3, 4, and 5, respectively. For the other three groups, the LED was used in the fast mode for 3, 5, and 10 seconds, respectively. The SBS of the brackets was measured on a universal testing machine. The adhesive remnant index (ARI) scores, damage to the porcelain, and fracture of the ceramic bracket bases were determined. No significant differences were observed for SBS between the eight groups (P=0.087). There was no significant difference between the groups' ARI scores, porcelain damage, and bracket base fracture (P=0.340, P=0.985, and P=0.340, respectively). There was a greater frequency of ARI scores of 0 for all groups. Fifty per cent of the porcelain facets displayed damage. Nineteen ceramic bracket base fractures were observed. No significant difference was found for the SBS of the groups with QTH and LED units and curing times. It is reliable to use LED with a 3-second curing time since it provided adequate bond strength for ceramic brackets bonded to porcelain surfaces.

Porcelain surface-conditioning techniques and the shear bond strength of ceramic brackets

The aim of this study was to compare the effects of various porcelain surface-conditioning techniques, used either alone or in combination, on the shear bond strength (SBS) of ceramic brackets cured with a light emitting diode (LED). Thirty glazed porcelain facets were randomly divided into three groups of 10. In group I, the porcelain surfaces were etched with 9.6 per cent hydrofluoric acid (HFA) for 2 minutes before silane application, in group II, the porcelain surfaces were sandblasted with aluminium oxide particles, etched with 9.6 per cent HFA for 2 minutes, and silane applied, and in group III, the porcelain surfaces were sandblasted with aluminium oxide particles before silane application. Spirit ceramic brackets were bonded with a light-cured composite resin (Light Bond) and a LED. All specimens were stored in distilled water at 37 degrees C for 24 hours and thermocycled. Bond strength was determined in shear mode at a crosshead speed of 0.5 mm/minute until fracture occurred. Analysis of variance indicated a significant difference between groups (P < 0.001). The lowest SBS was found in group III (5.46 +/- 1.34, P < 0.001). No significant difference was found between group I (11.38 +/- 1.65) and group II (10.45 +/- 1.15; P > 0.05). Surface treatment with HFA and a silane coupling agent produced the highest bond strength. Sandblasting before HFA and silane application did not significantly increase bond strength. Silane application to sandblasted porcelain provided poor results in vitro and clinical trials are needed to determine its reliability for bonding ceramic brackets to ceramic crowns.

Effects of Light-Emitting Diode and Halogen Light Curing Techniques on Ceramic Brackets Bonded to Porcelain Surfaces

The objectives of this study were to test the efficiency of LED curing devices in bonding ceramic brackets to porcelain surfaces and to compare the effects of LED and halogen curing techniques on shear bond strength of ceramic brackets. A total of 20 glazed porcelain facets were randomly divided into two groups of 10. Porcelain surfaces were etched with 9.6% hydrofluoric acid for 2 minutes, and silane was applied on the etched porcelain surface. Ceramic brackets were bonded with an LC composite resin cured with soft start mode LED and a halogen light. Bond strengths, as determined in the shear mode, were higher in the LED group (P < .001). LED curing units with the soft start polymerization mode were more effective than halogen curing units in bonding ceramic brackets on porcelain surfaces. The type of curing light must be considered as an important factor affecting bond strength of ceramic brackets on porcelain surfaces.