Amirhossein Mirhashemi; Nasim Chiniforush; Rashin Bahrami
Abstract
Aim: Tooth bleaching is known as a non-invasive, cosmetic treatment option. It has been noted that bleaching has a detrimental impact on bond quality of enamel. With increasing adult patients who need multidisciplinary treatments, concurrency of bleaching with other treatments such as composite filling ...
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Aim: Tooth bleaching is known as a non-invasive, cosmetic treatment option. It has been noted that bleaching has a detrimental impact on bond quality of enamel. With increasing adult patients who need multidisciplinary treatments, concurrency of bleaching with other treatments such as composite filling or orthodontic treatment in which bond quality to enamel plays an important role, a dilemma has arisen. This review aimed to evaluate the impact of the laser-assisted bleaching technique on bond quality of enamel to brackets drawn from the available literature.Methods: All original articles that evaluated the effect of laser-assisted bleaching on bond strength of enamel in MEDLINE (NCBI PubMed and PMC), EMBASE, Scopus, Corchane Library, Web of Science, and Google Scholar were assessed until July 2022.Results: Six in-vitro studies were entered into this review. All of them evaluated bond strength of orthodontic brackets to bleached enamel expect one, in which composite resin bond to bleached enamel was examined. Several laser types including Nd:YAG, Er:YAG, CO2, diode, and LED were used in these studies. A few studies indicated that bond strength of bleached enamel is higher after laser-assisted bleaching compared to the conventional bleaching technique, whereas others did not.Conclusion: In cases of immediate bonding to bleached enamel, the laser-assisted bleaching approach is recommended. There is still a need for more studies in this field because of the high diversity of laser types, bleaching agents, and type of adhesives that have been introduced to the market recently.
Orthodontics
Somasundara Ramadevi; Anjith Shirley Gladstone; Sarala Manjappa Laxmikanth; Chunduri Raghunandan; Jairaj Vani; Shrikanth Shendre; Khan Mahamad Irfanulla; Maqbool Sameena Begum; Riyaz Khadeer
Abstract
Aim: The use of pre-procedural mouth rinse for prevention of COVID-19 can reduce viral load but can alter the bond strength. The purpose of this study was to determine any correlation between the use of these pre-procedural mouth rinse and the shear-bond strength (SBS) of orthodontic brackets.Methods: ...
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Aim: The use of pre-procedural mouth rinse for prevention of COVID-19 can reduce viral load but can alter the bond strength. The purpose of this study was to determine any correlation between the use of these pre-procedural mouth rinse and the shear-bond strength (SBS) of orthodontic brackets.Methods: Thirty-three maxillary premolars extracted for orthodontic purposes were used. The buccal surfaces of all teeth were bonded with orthodontic brackets. Later, each tooth was embedded into acrylic resin and stored in distilled water. Teeth were randomly divided into three groups (group I: hydrogen peroxide mouth rinse, group II: povidone-iodine mouth rinse, and group III: artificial saliva), and stored in each solution for 12 hours. Later, each tooth was subjected to SBS testing using a universal testing machine. Data were statistically evaluated using one-way analysis of variance (ANOVA) and post hoc test (Tukey’s HSD) with a significance of p< 0.05.Results: The highest mean SBS was observed in the artificial saliva (control group), followed by the povidone-iodine and hydrogen peroxide groups.Conclusion: Hydrogen peroxide mouth rinses should not be used during fixed orthodontic treatment because it alters bond strength.
Arman Mohammadi Shayan; Monireh Rassouli; Soodabeh Kimyai; Hadi Valizadeh; Mohammad Hossein Ahangar Atashi; Sahand Rikhtegaran
Abstract
Background: White spot lesion is considered as one of the main problems in the orthodontic treatment. Brackets used in fixed orthodontic treatment create an environment that provides enamel demineralization.Objectives: The objective of the current study was to perform an in vitro study to compare different ...
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Background: White spot lesion is considered as one of the main problems in the orthodontic treatment. Brackets used in fixed orthodontic treatment create an environment that provides enamel demineralization.Objectives: The objective of the current study was to perform an in vitro study to compare different applications of fluoride supplements on enamel demineralization adjacent to orthodontic brackets and finally to understand the best supplement to recommend the patients.Methods: One hundred and twenty extracted caries-free human premolar teeth were randomly assigned into six groups: group 1: Control group, group 2: Fluoride toothpaste, group 3: Fluoride toothpaste/mouth rinse, group 4: Fluoride toothpaste/vanish, group 5: Fluoride toothpaste/gel and group 6: Fluoride toothpaste/foam. After bonding the brackets to the teeth, the fluoride supplements were applied based on each group above, except the control group. Then all the specimens were cycled for 30 days in demineralization solution for 8 hours a day, rinsed, placed in artificial saliva for 4 hours a day, brushed (except the control group), and put back to artificial saliva for 12 hours. DIAGNOdent laser fluorescence was used to quantify the demineralization changes. Results: Significant differences existed between all fluoride-containing groups and control group. Analyses of the results showed a significant difference between control group and the rest 5 treatment groups (P < 0.001). Other significant differences were between groups 2/5, 3/5, 2/4 and 5/6 (P < 0.05). There was no significant difference among the other groups (P > 0.05).Conclusions: According to the results, all fluoride supplements could be used during orthodontic treatment to decrease the enamel demineralization. It has been illustrated that fluoride-containing toothpaste and mouth rinse is better than no fluoride treatment but is not effective as well as fluoride gel and varnish.
Mojgan Kachoie; Baharak Divband; Masoumeh khatamian; Azin Nourian
Abstract
Introduction: NiTi wires which are considered the ideal alloys used during the alignment and leveling stage of comprehensive orthodontic treatment exhibit very high frictional resistance. Therefore, overcoming such resistance to sliding results in a rapid tooth movement and proper anchorage control. ...
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Introduction: NiTi wires which are considered the ideal alloys used during the alignment and leveling stage of comprehensive orthodontic treatment exhibit very high frictional resistance. Therefore, overcoming such resistance to sliding results in a rapid tooth movement and proper anchorage control. Recently, coating the wires with nanoparticles has been introduced to decrease resistance to sliding. The aim of this invitro study was to evaluate effect of ZnO nanoparticles on resistance to sliding of nickel titanium orthodontic wires. Materials and methods: 40 straight pieces of 0.016-inch NiTi wires were evaluated in two groups with and without spherical ZnO nanoparticle coating, along with 40 standard system 0.018 stainless steel brackets. ZnO nanoparticles were deposited on NiTi wires and analyzed by SEM. A universal testing machine was used to determine friction between the wires and brackets at an angle of 5°. Student’s t-test were used for data analysis. Results: The SEM results confirmed the homogeneous deposition of ZnO nanoparticles on NiTi wires. At 5º angle between the wires and brackets the means of frictional forces were 1.2475±0.13 and 1.5075±0.12 N with and without ZnO nanoparticle deposits on the wires, respectively, revealing a significant decrease of 17.24% in frictional forces in coated wires (P<0.001).Conclusion: Based on the results of this study, ZnO nanoparticle coating reduces the resistance to sliding of nickel titanium orthodontic wires.
Masood Feizbakhsh; Mehrdad Barekatain; Ehsan Borhani; Fatemeh Teimoori
Abstract
Aim: The aim of this study was to compare the shear bond strength [SBS] of two different light sources, light-emitting diode and quartz-tungsten halogen, under thermal cycle frequencies. Method and materials: Sixty human premolar teeth were divided into two groups, on which composite (Transbond ...
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Aim: The aim of this study was to compare the shear bond strength [SBS] of two different light sources, light-emitting diode and quartz-tungsten halogen, under thermal cycle frequencies. Method and materials: Sixty human premolar teeth were divided into two groups, on which composite (Transbond XT™ adhesive paste) cured with light-emitting diode in group I, and with quartz-tungsten halogen in group II. Samples thermocycled 500 cycles, the exposure to each bath was 10 seconds and the transfer time between the two baths was 10 seconds. 500 cycles between 5°C and 55°C were performed. An Instron testing machine [Dartec Hc.10, England] was used for the shear bond test at a crosshead speed of 1mm/min. Force was applied directly to the bracket–tooth interface. The load at failure was recorded by a personal computer connected to the test machine. SBS values were expressed in mega Pascal [MPa]. T-test was used to compare the shear bond strength between two groups. Results: The comparison of both groups indicated that the quartz-tungsten halogen groups demonstrated higher mean shear bond strength [p=19.947Mpa] than light-emitting diode groups [19.878Mpa]. There was no statistical difference in the shear bond strength values between the two light sources. [P value =0.918] Conclusions: Both light sources showed favorable shear bond strength performance and there was no statistical difference in the shear bond strength values between these two light sources.