The bristle wear and bristle tip morphology were also examined after simulated tooth-brushing.

Orthodontic brackets (Roth-P/1st and 2nd premolar S/D- Slot 0.18") were bonded (Transbond XT®) to the smoothest surface of each of 45 extracted human molar and premolar teeth.

Test specimens were randomly divided into three groups: Group 1, control group with no brushing; Group 2, brushing with the Oral B Indicator 35; Group 3, brushing with the Colgate 360º.

Samples were adapted to a machine that simulated tooth-brushing.

The bond strength of each bracket to each tooth was assessed with a mechanical testing machine.

The bristle wear and bristle tip morphology indices were also assessed.

Statistically significant differences were defined for p < 0.05.

The average bond strengths (range: 90.18-90.89 kgf/cm²) did not differ among the three groups.

The Colgate 360º showed less bristle wear and a better bristle tip morphology than the Oral B Indicator 35 toothbrush.

However, use of either toothbrush did not decrease the bond strength of the orthodontic brackets.

Therefore, patients undergoing orthodontic therapy can safely use either toothbrush.