Dental Materials
Masomeh Esmaily; Manijeh Mohammadian; Neda Faghfourian
Abstract
Aim: The primer-containing composites, which eliminate the bonding step, decrease clinical time and securely attach the bracket to the tooth. Given the significant role of bonding in the bond strength of orthodontic adhesives, this study aims to investigate the effect of using a universal bond with two ...
Read More
Aim: The primer-containing composites, which eliminate the bonding step, decrease clinical time and securely attach the bracket to the tooth. Given the significant role of bonding in the bond strength of orthodontic adhesives, this study aims to investigate the effect of using a universal bond with two types of primer-containing composites on the bond strength of these composites.Methods: Sixty healthy premolars were collected and divided into four equal groups: GC Ortho Connect composite, GC Ortho Connect composite with a universal bond, OrthoCem composite, and OrthoCem composite with a universal bond. The shear bond strength was measured using a universal testing machine, and the residual adhesive index was measured using a stereomicroscope at a 10x magnification.Results: The shear bond strengths of the GC Ortho Connect group without a universal bond, the GC Ortho Connect group with a universal bond, the OrthoCem group with a universal bond, and the OrthoCem group without a universal bond were calculated to be 21.54, 12.88, 12.37, and 11.68 MPa, respectively. The analysis of variance (ANOVA) showed that the GC Ortho Connect group without a universal bond had a significantly higher shear bond strength than the other groups. The results also indicated that the universal bond reduced the shear bond strength in the GC Ortho Connect composite (p-value <0.001) and had no significant effect on the shear bond strength of the OrthoCem composite (p-value=1.000).Conclusion: While the application of a universal bond considerably diminishes the shear bond strength in the GC Ortho Connect composite, it does not exert a significant influence on the OrthoCem composite. This suggests that the effectiveness of a universal bond may be dependent on the specific composite used, necessitating further investigations into optimizing bonding methods for different composite materials in orthodontics.
Ali Tayebi; Farnoosh Fallahzadeh; Hamid Raji; Kazem Khosravi
Abstract
Introduction: One of the most important aspects of self-etching primer system in orthodontics is the duration of adhesive resin use after application of self-etching primer. Evaluating time delay effect on band strength is the objective of this study.Materials and methods: In this interventional-axperimental ...
Read More
Introduction: One of the most important aspects of self-etching primer system in orthodontics is the duration of adhesive resin use after application of self-etching primer. Evaluating time delay effect on band strength is the objective of this study.Materials and methods: In this interventional-axperimental study, premolar with sound buccal enamel were selected, and randomly divided in four groups, In the first group buccal surface were etched for 30 seconds, with 37% phosphoric acid. After washing and drying, primer XT was applied on teeth and brackets. Transbond XT was used in bonding. Light with 500 mw was glowed from mesial, occlusal and distal surface for fifteen seconds, 5 and 10 minutes respectively. After thermocycling of all samples, debonding strength was measured with the help of DARTEC machine. Analysis was done by ANOVA and Duncan.Results: The highest shear bond strength (19.4 Mpa) was seen in group one and the lowest (9.87 Mpa) in group four. Between the remaining groups and group one, there was a significant difference in mean shear bond strength. Scan electron microscope showed a strong deep tag between tooth enamel surface and adhesive in group one.Conclusion: Significant difference in shear bond strength of two groups, traditional etching and self-etching primer was observed. Mean of shear bond strength with self-etching primer method was acceptable and delay in applying resin composite had no significant effect on shear bond strength of brackets to enamel.
