Individual toothbrushing habits are usually consistent. Frequency, pattern and duration are different aspects of the toothbrushing habit. The aim of this study was to analyze the effect of habitual toothbrushing in children. The schoolchildren (n = 110) aged 13, were examined clinically before and after brushing their teeth in the habitual way; the brushing procedure was filmed without the children's knowledge. From the film, the pattern of brushing was assessed by three dentists, and the duration measured in seconds. Frequency of toothbrushing was assessed by postal questionnaire 2 months after the clinical examination. The examination included both photographed plaque and disclosed plaque diagnosed clinically. From the photographs, plaque was measured by computer planimeter as a % of plaque area and clinically by the oral debris index recommended by WHO. Subjects who had little plaque before toothbrushing were excluded from the analyses. Frequency seemed to affect plaque removal only in boys and only in the maxillary teeth. The pattern affected plaque removal in girls, but for boys, this aspect of toothbrushing affected only the left side of the jaws. Duration had produced the strongest effect on plaque removal. Therefore, duration of toothbrushing should be emphasized more in dental health education.