Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets

• Published in: Indian journal of dental research Vol. 23; no. 6; pp. 747 - 752
• Main Authors: Machado, Claudia, Dutra Borges, Boniek, Rodrigues Araujo, Gustavo, Souza dos Santos, Alex, Dametto, Fabio, de Sa Leitao Pinheiro, Fabio
• Format: Journal Article
• Language: English
• Published: Mangalore Medknow Publications 01-11-2012; Medknow Publications and Media Pvt. Ltd; Medknow Publications & Media Pvt. Ltd; Wolters Kluwer Medknow Publications
• Subjects: Adhesives; Analysis; Bond strength; Curing; halogen lamp; LED; Light-emitting diodes; nanofiller; Orthodontics; Teeth; Bond strength; orthodontics; LED; nanofiller; halogen lamp
• ISSN: 0970-9290; 1998-3603
• DOI: 10.4103/0970-9290.111252

Context: The effect of different curing units on bond strength of orthodontic brackets is still unclear when utilizing nanofilled composites in comparison with traditional Transbond-XT.
Aim: To evaluate the influence of two adhesive promoters and two curing-light units on the shear bond strength (SBS) of orthodontic brackets.
Settings and Design: The factors under study were adhesive promoters (nanofilled composite - Filtek-Z350 flowable restorative and conventional orthodontic adhesive - Transbond XT) and curing-light units (halogen lamp - Ultralux and LED device - Radii-Call).
Material and Methods: Forty lower bovine incisors were utilized. The teeth were distributed in four groups (n = 10) according to the combination between adhesive promoters and curing-light units. Scotchbond Multipurpose-Plus and Transbond-XT primer were used to bond Filtek-Z350 Flowable Restorative and Transbond-XT, respectively. After storage in distilled water for 24 h, the brackets were subjected to SBS test at a speed of 0.5 mm/min until bracket debonding. The Adhesive Remnant Index (ARI) was assigned at fractured specimens.
Statistical analysis used: Analysis of variance and Tukey test were utilized. The Kruskal-Wallis test was used to compare ARI scores between the groups (p<0.05).
Results: There was statistically significant difference between the adhesive promoters tested. Transbond-XT showed higher SBS means than Filtek-Z350. There was no statistically significant difference between both curing-light units tested in this study, neither between ARI scores.
Conclusions: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.