Does microetching enamel reduce bracket failure when indirect bonding mandibular posterior teeth?

To determine if microetching the mandibular premolars and first molars prior to acid-etching reduced bracket failures during the first six months of orthodontic treatment.

Sixty four patients with 384 mandibular first molar and premolar brackets were used in a split-mouth study design. In each patient the teeth on one side were acid-etched and the contralateral teeth were microetched prior to acid-etching. The microetched side was alternated in successive patients. The brackets were indirect bonded to the teeth on both sides. First time bracket failures were recorded over a 6-month period.

Two brackets (1 per cent) came loose on the microetched enamel side and four brackets (2.1 per cent) failed on the conventionally acid-etched side. This difference was not clinically or statistically significant (p = 0.41).

The addition of microetching prior to acid-etching does not result in fewer bracket failures during the first six months of treatment.