The efficacy and safety of two manual toothbrushes (Dentrust and the Oral-B P35) were evaluated in orthodontic patients classified by their treating orthodontist as having established gingivitis. Fifty-seven healthy adolescent subjects, who were fully bonded and banded with fixed orthodontic appliances, were randomly assigned to use one of the two toothbrushes for the duration of the four-month study. The subjects were given instructions with their new assigned toothbrush and agreed to use only these products at home, twice a day between orthodontic visits. On evaluation days at one, two and four months the patients reported to the clinic having not brushed for 12-16 hours, and were evaluated for plaque area and gingivitis in this single blind study. Gingivitis scores decreased significantly in the Dentrust group from baseline to the conclusion of the study. There was no significant statistical decline in gingivitis in the Oral-B P35 group until the four-month evaluation. Overnight plaque formation scores were similar for both groups during the study. After brushing for a timed one-minute period, both toothbrushes removed significant plaque area throughout the study. On total plaque levels, the Dentrust group was significantly lower on after-toothbrushing plaque area mean scores compared to the Oral-B P35 group at two and four months. No side effects were reported or observed during the study attributed to the use of the assigned toothbrushes.