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Document Type |
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Thesis |
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Document Title |
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Bonding of Orthodontic Composite Attachments to Ceramic Material: An In-vitro Study ربط المرفقات المركبة لتقويم الأسنان بمادة السيراميك: دراسة مخبرية |
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Subject |
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Faculty of Dentistry |
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Document Language |
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Arabic |
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Abstract |
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Objectives: The aim of this in-vitro study is to evaluate the effect of different surface conditioning methods, adhesive systems and resin composites on the shear bond strength (SBS) of composite attachments bonded to lithium disilicate ceramics as well as to evaluate the effect of different surface conditioning methods on the surface roughness of lithium disilicate ceramic materials.
Methods: A total of 180 IPS e.max CAD specimens with the dimensions of 13 x 7.5 x 2 mm3 were used in this study. 60 samples were divided according to the surface conditioning methods used (n=15). Group I: control/no surface treatment, group II: 9.6% hydrofluoric acid (HFA) etching, group III: 37% phosphoric acid (PhA) etching, group IV: air abrasion (AA) with 50 μm AL2O3. The surface roughness value was measured using a Profilometer and Atomic Force Microscopy (AFM). One hundred twenty specimens were divided into three groups according to the conditioning methods (n=40) described above without the control group. The groups were subsequently divided according to the adhesive (n=20) into: Assure universal adhesive (AU) or Single Bond universal adhesive (SBU). Furthermore, the groups were subdivided according to the composite type (n=10) into Filtek™ Z350 XT composite or Filtek™ Z350 XT flowable composite. All the ceramic blocks with the bonded composite attachments were subjected to 10,000 thermal cycles of alternate 30 seconds baths at 5°C and 55°C, with a 5 seconds interval between immersions using a thermocycler then to SBS test using Universal testing machine. Descriptive and group comparisons were calculated using independent sample t-test, one-way and multiple ANOVA, and post-hoc Tukey tests. A significance level of 0.05 was set for all analysis.
Results: The results showed that air abrasion group had significantly the highest surface roughness (1.20 ± 0.30 μm), while the lowest value was recorded for the control group (0.24 ± 0.08 μm) (P < .05). Moreover, hydrofluoric acid etching and air abrasion gained the highest SBS value (15.82 ± 4.72 and 14.91 ± 5.38 MPa) respectively (P > 0.05). For adhesive systems, AU had significantly higher SBS than SBU (14.04 ± 6.04 and 9.93 ± 6.80 MPa) respectively (P = 0.001). Furthermore, Filtek™ Z350 XT gave significantly higher SBS (13.79 ± 7.47 MPa) than Filtek™ Z350 XT flowable composite (10.18 ± 5.38 MPa) (P = 0.003). The combination of air abrasion with AU and Filtek™ Z350 XT composite gave the highest SBS (21.80 ± 3.86 MPa).
Conclusion: 9.6% Hydrofluoric acid and air abrasion are recommended techniques for reliable bond strength between composite attachments and lithium disilicate ceramic but they can affect the surface topography. PhA can be recommended if used with AU. AU gave a stronger bond than SBU. Moreover, Filtek™ Z350 XT gave higher bond strength than the flowable type.
Key words: Attachments; ceramics; clear aligner; composite; orthodontics; surface conditioning. |
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Supervisor |
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Prof. Amal Ibrahim Linjawi |
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Thesis Type |
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Master Thesis |
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Publishing Year |
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1445 AH
2023 AD |
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Co-Supervisor |
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Dr. Ahmed Ibrahim Masoud |
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Added Date |
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Tuesday, November 14, 2023 |
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Researchers
| البشير عبدالله السعود | Alsaud, Bashair Abdullah | Researcher | Master | |
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