From a questionaire of oral hygine about the tooth brushing habits of 150 male and female patients who had completed orthodontic treatment, the following results were obtained: 1. After starting orthodontic treatment, the frequency and duration of toothbrushing was increased. These results indicated that an interest in oral hygine was increased by orthodontic treatment. This finding was more marked in women than men. 2. After the removal of appliance, the frequency and duration of toothbrushing were seen to decrease
