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Updated: Jan 31, 2026

Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
Adhesive precoated bracket systems and operator coated bracket systems: Is there any difference? A systematic review
Objectives:
To investigate whether adhesive precoated brackets (APC) are more efficient than operator-coated brackets (OPC) regarding failure rate, bonding time, patient experience, gingival health, plaque accumulation, and white spot lesion formation.
Materials And Methods:
Five online databases: Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, PubMed, MEDLINE, and Web of Science were searched for potential eligible randomized controlled trials (RCTs). A Google Scholar and gray literature search was undertaken. References of included studies were screened for potential eligible studies. Results were collated from each database and modified Cochrane data extraction forms were completed. Quality assessment was performed using Cochrane RoB 2.0 tool for RCTs.
Results:
Five studies met the inclusion criteria. All reported failure rates using metal brackets for both APC and OPC systems except one that compared clear APC to clear OPC. Three studies reported bonding time differences between the bracket systems. A quantitative synthesis of four studies reporting failure and three reporting bonding time was undertaken. Random effect meta-analysis determined there were no statistically significant differences in bond failures between bracket systems with an odds ratio of 0.890 (P = .808). Bonding time showed a statistically significant (P = .01) but not clinically significant shorter bonding time with OPC. There was insufficient evidence to assess plaque accumulation, gingival health, and either patient or operator experience.
Conclusions:
There is no superiority of either bracket system regarding failure rate. OPC are statistically significantly superior over APC in bonding time although this is most likely not clinically significant.
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