A split-mouth technique was used. The teeth in the maxillary right and mandibular left quadrants were prepared with a fluoridated paste only, and the teeth in the maxillary left and mandibular right quadrants were prepared with plain pumice before bonding the precoated brackets. A total of 627 brackets in 34 orthodontic patients (20 female, 14 male) were included in this study; 315 brackets were bonded after pumice treatment, and 312 were bonded after paste treatment. The patients were followed for 6 months to determine the rates of bracket failure.
The overall failure rate was 8 % . The failure rates for pumice and paste were 4.8 % and 11.2 % , respectively. The McNemar test showed a statistically significant difference between the 2 groups. Based on tooth type, the failure rate of the maxillary canine and the mandibular central incisor brackets were significantly different for paste and pumice. There was also a difference in the survival rates of the brackets in both groups.
Preparation of the enamel surface with fluoridated paste before bonding with self-etching primer is not recommended. However, the use of plain pumice is recommended, even if it is time-consuming.