Enamel Surface Roughness Evaluation after Bracket Debonding: Comparison between Light Cure and Self Cure Adhesive Resin 3-Dimensional Profilometric Study

Introduction: After fixed orthodontic treatment, following bracket removal, the debonding procedure should lead to restitutio ad integrum of the enamel or, at least, restore the enamel surface as closely as possible to its pretreatment condition. Adhesion of brackets in orthodontics is that they should be strong enough to prevent failure during all treatment but also low enough, so that enamel damage would be minimal during bracket removal after treatment. Material and Methods: A total of 60 premolars were collected and stored in distilled water. The extracted teeth were divided into two groups of 30 each, group A was to be bonded with self?cure adhesive while group B light cure adhesive was to be used. A standardised protocol was followed for adhering the brackets to the tooth surfaces. All the teeth were bonded with metal brackets (3M Unitek, Gemini Twin Brackets 0.022 slot). In group A, bonding adhesive (3M Unitek self cure adhesive primer) was applied. In group B, the bonding adhesive (3M Unitek light cure adhesive primer) was photopolymerized for 10 seconds after application. Results: Surface roughness of enamel as assessed by profilometry shows that light cure adhesive creates more roughness as compared to self cure adhesive. To conclude, self cure adhesive is clinically better than light cure adhesive. Discussion: In the present study enamel surface roughness were compared after debonding. Enamel surface roughness after bracket debonding depends o

Comparative study of sorption and solubility of heat‑cure and self‑cure acrylic resins in different solutions.

Objective: The objective of this study was to compare the sorption and solubility of heat‑cure and self‑cure acrylic resins in different solutions. Materials and Methods: One heat‑cure acrylic resin (Trevalon) and one self‑cure acrylic resin (Rapid Repair) were studied. Five groups of square‑shaped specimens (20 mm × 20 mm × 2 mm) were prepared for each acrylic resin and then immersed in five solutions: distilled water, artificial saliva, denture cleansing solution, distilled water, and denture cleaning solution for 12 h alternatively, artificial saliva and denture cleaning solution for 12 h alternatively at 37 ± 2°C, and tested sorption and solubility by weight gain/loss method, respectively, after 1, 6, and 11 weeks. The data were analyzed by one‑way analysis of variance followed by post hoc Tukey’s test. Results: Water sorption mean values varied from 17.5 ± 0.88 to 27.25 ± 1.04 μg/mm3 for heat cure and from 12.75 ± 0.55 to 19.75 ± 1.04 μg/mm3 for self‑cure in the different solutions after different interval periods of 1, 6, and 11 weeks. These values were statistically significant (P < 0.001). Water solubility mean values varied from 0.25 ± 0.55 to 1.5 ± 0.55 μg/mm3 for heat cure and from 1.5 ± 0.55 to 6.5 ± 0.55 μg/mm3 for self‑cure in the different solutions after different interval periods of 1, 6, and 11 weeks. These values were statistically not significant (P > 0.05). There was no linear correlation between sorption and solubility values. Overall, analysis of results showed the maximum sorption value in denture cleansing solution followed by alternative soaking in distilled water and artificial saliva. Least sorption was observed with artificial saliva followed by distilled water. Conclusion: Both heat‑cure and self‑cure acrylic resins showed varying water sorption and solubility. The results of both water sorption and solubility showed compliance with the International Standards Organization specification. No correlation was found between water sorption and solubility. Artificial saliva solution is a better storage medium than distilled water and denture cleansing solution for both heat‑cure and self‑cure acrylic resins.

Clearfil Protect Bond™ versus Uni‑Etch™ antibacterial self‑etchant: A war of giants against shear bond strength.

Aims and Objectives: To use antibacterial agents with two conventional bonding systems and evaluate the shear bond strength (SBS) of bracket to enamel. Materials and Methods: Overall, 120 human‑extracted first premolars were used. The specimens were equally divided into six sub‑groups of 20 samples. Control groups were bonded with Transbond XT™ light cure (Group I, after etching with 37% phosphoric acid, 3M Unitek™) and Unite™ self‑cure adhesive (Group II, after etching with 37% phosphoric acid, 3M Unitek™). Experimental groups included teeth surface first coated with Clearfil Protect Bond™ (Kuraray, Osaka, Japan) (and then bonded with Transbond XT™ [Group III] or Unite™ [Group IV]) or bonded with Uni‑Etch™ antibacterial self‑etchant (and then bonded with Transbond XT™ [Group V] or Unite™ [Group VI]). The third generation MBT bracket bonding system with 0.022 slots was used for bonding. All specimens were tested on Instron machine 5567 (SIES Institute of packaging, Nerul, Navi Mumbai, India) to evaluate the SBS. The sheared surfaces were also investigated with a stereomicroscope to assess adhesive remnants index (ARI scores) on the specimen surfaces. Results: Mean SBS in Group I–Group VI was 10.53 (2.91), 9.12 (2.56), 9.86 (1.98), 6.96 (2.92), 9.57 (2.02), and 7.65 (2.34) megapascals, respectively. Significant differences were only seen between Group III and IV and between Group II and IV. With respect to ARI scores, significant differences were seen only for comparison between Groups II, IV, and VI. Conclusion: Newly developed antibacterial agent could be used with conventional bonding systems effectively to decrease white spots; when used with Transbond XT™ light cure, the original SBS did not get affected, but when used with Unite™ self‑cure bonding system, it led to reduced SBS significantly.

Effect of an intermediate bonding resin and flowable resin on the compatibility of two-step total etching adhesives with a self-curing composite resin / 대한치과보존학회지

This study compared the effect of an activator, intermediate bonding resin and low-viscosity flowable resin on the microtensile bond strength of a self-curing composite resin used with two-step total etching adhesives. Twenty extracted permanent molars were used. The teeth were assigned randomly to nine groups (n=10) according to the adhesive system and application of additional methods (activator, intermediate adhesive, flowable resin). The bonding agents and additional applications of each group were applied to the dentin surfaces. Self-curing composite resin buildups were made for each tooth to form a core, 5mm in height. The restored teeth were then stored in distilled water at room temperature for 24h before sectioning. The microtensile bond strength of all specimens was examined. The data was analyzed statistically by one-way ANOVA and a Scheffe's test. The application of an intermediate bonding resin (Optibond FL adhesive) and low-viscosity flowable resin (Tetric N-flow) produced higher bond strength than that with the activator in all groups. Regardless of the method selected, Optibond solo plus produced the lowest microTBS to dentin. The failure modes of the tested dentin bonding agents were mostly adhesive failure but there were some cases showed cohesive failure in the resin.

Effects of activators contained in adhesives on dentin bond strengths / 대한치과보철학회지

STATEMENT OF PROBLEM: An incompatibility between the initiator systems of self-curing composite resins and light-curing adhesives was supposed recently. PURPOSE: The purpose of the study was to evaluate the influence of activators for self/dual bonding on dentin shear bonding strengths. MATERIAL AND METHODS: Fifty human molars were divided into 5 groups. A flat dentin surface was created for each tooth. A self-curing composite resin (Luxacore) was bonded with the following adhesives (n = 10): One-Step, Prime and Bond NT, AdheSE, Prime and Bond NT and AdheSe were also used in combination with activators. Shear bond strengths were measured after 24 hours of water storage. The specimens were loaded in shear in the Instron until failure at a 1 mm/min crosshead speed. Data were compared using one-way ANOVA and Tukey HSD test (alpha = 0.05). RESULTS: The dentin adhesive systems in order of decreasing median bond strength were One-Step > Prime & Bond NT with activator, AdheSe with activator > Prime and Bond NT, AdheSe. Among adhesives, One-Step had the highest bond strength. Prime & Bond NT with activator had higher bond strengths than Prime and Bond NT that was used alone, and so was AdheSe. CONCLUSION: Shear bond strengths were increased in Prime and Bond NT and AdheSe when these were used with activators comparing used without activators. But using activators was not effective clinically comparing One-Step.

Consulting Services on Self-cure of Cough Caused by Cold:Analysis and Practice / 中国药房

OBJECTIVE:To introduce a self-cure method for the cough caused by cold.METHODS:By placing control group and trial group,30 cases(control group)were assigned to receive Dextromethorphan Hydrobromide oral liquid and 32 cases(trial group)to employ self-cure method for cough caused by cold.And a self-cure method for the cough caused by cold was induced.RESULTS & CONCLUSION:The practice of self-cure method can speed up the self-cure of cough caused by cold and this method deserves to be popularized.