ABSTRACT
Background: The aim of this study was to evaluate the effect of separately curing the unfilled resin for increased bond strength of the orthodontic brackets as the literature shows both studies that support and contradict this aspect. Methodology: The sample consisted of 120 specimens randomly grouped into four of 30. The tooth was cleaned of tissue and debris and stored in a distilled water solution until the procedures of bonding. The surface of the enamel was conditioned with pumice, and acrylic blocks were designed for the tooth to be mounted onto them. The buccal surfaces of all the teeth were prepared by etching the enamel with 37% phosphoric acid for a time period of 30 seconds and washed for 20 seconds under running water. Stainless steel brackets (Victory Series™ MBT, 0.022 Slot) were used for all the samples in the study, and the bonding procedure was conducted on the same day for all the groups. The artificial saliva was used for the storage of samples for 24 h after bonding, and shear bond strength testing was conducted using an Instron machine in shear or peel mode at a crosshead speed. Results: The highest mean bond strength calculated was for the conventional technique (17.45 mpa), while it was the lowest for no primer adhesive (11.21 mpa). Group IV had a greater distribution of ARI scores than groups I, II, and III. Conclusion: Group IV achieved the highest bond strength when compared to other groups, with an ARI score of 3. Group III had less bond strength, likely due to incomplete curing of the primer due to insufficient exposure to light. Transbond XT can be used without primer, making bonding, debonding, and cleaning procedures easy and less time-consuming.
ABSTRACT
Background: Acid etching enamel improves resin-enamel adhesion and adhesive characteristics, but has pros and cons. The effects of laser etching on the bonding of orthodontic brackets vary depending on the wavelength, power output, exposure duration, and energy delivered. Materials and Methods: This study used a new 1064-nm diode laser to irradiate 30 freshly extracted human premolars. They were divided into three groups: group A, group B, and group C. Acid etching was used for 1 min to bond bracket to tooth surface, and Indian ink was used for 30 s. Group C uses acid etching for 1 min following 30 s of laser irradiation with Indian ink. Results: In comparison to the other groups, group C's acid etching after laser irradiation has considerably stronger bond strength (P = 0.05). Orthodontic brackets in group B exhibited considerably poorer shear bond strength than those in the other groups. Conclusion: Acid etching improves the adhesion of orthodontic composite resin to human enamel following laser irradiation, but can interfere with the adhesion of composite resin.
ABSTRACT
Background: Nanosized antibacterial agents can be used to prevent biofilm buildup on orthodontic appliances and auxiliaries, limiting microbial adherence and preventing caries. Nanoparticles (NPs) can enhance the antibacterial properties of orthodontic materials due to their smaller particle size and larger surface area. Materials and Methods: The study's material analysis was divided into four groups, numbered I through IV, using Transbond XT Primer as a control and modifying group I by adding various antibacterial agents. 98.1 g of mutans-sanguis agar was dissolved in 1,000 ml of warm distilled water and autoclaved for 15 minutes at 121°C and 15 lb pressure. 176 disk specimens of 6 mm in diameter were created, sterilized in an autoclave, and heated to 60°C in a hot air oven for 1 hour. Ten milliliters of primer containing different antimicrobial agents was applied to the sterilized disks. Four petri plates were used for each concentration, with 16 disks in each group. 44 petri plates in all were utilized. Results: The orthodontic primer modified by the addition of antibacterial agents showed a significantly increased antimicrobial activity, and nanobenzalkonium chloride (BAC) at 5% concentration showed the highest antimicrobial efficacy among all groups. Nanohydroxyapatite showed the least. Conclusion: Within the confines of the current investigation, it was determined that the addition of antibacterial agents had significantly higher antimicrobial activity and BAC at 5% concentration had the highest antimicrobial efficacy of all the groups.
