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Updated: May 1, 2026

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions
Published on: July 22, 2016
Survival analysis of brackets and tubes: A twelve-month assessment
1a Adjunct Associate Professor, Department of Orthodontics, Dental Research Institute and School of Dentistry, Seoul National University; Private practice, Seoul, Korea.
Objective:
To compare the clinical performance of brackets bonded to anterior and posterior teeth, including second molars.
Materials And Methods:
One operator, using the straight-wire technique, bonded metallic brackets to the teeth of 127 consecutive patients. All patients were observed for 12 months during their regular orthodontic appointments. Bracket failures were recorded and summarized for statistical analysis. The Cox proportional hazards regression analysis was performed to evaluate bracket failure rates.
Results:
Statistically significant differences in survival rates were observed between molar tubes and anterior brackets (P < .05). Twelve-month failure rates of incisor, canine, premolar, and molar brackets were 3.6, 1.6, 4.8, and 11.6%, respectively. The first and second molar did not show significant difference in bond failure. Young patients (age <18 years) showed a higher failure rate than old patients (≥18 years).
Conclusions:
Brackets directly bonded to the buccal surfaces of molars failed significantly more often than those directly bonded to anterior teeth or premolars, but showed acceptable failure rate especially in adult patients. Bonding on second molars seems to be as reliable as bonding on the first molars.
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