Black & white drawing
Left - correct position; the bristles are held vertical, for effective brushing and to avoid gingival traumtization. Center - incorrect, oblique, position of the bristles on an upper tooth, causing them to straddle the occluso-palatal line angle; those on the occlusal side function inadequately, while those on the palatal side tend to reach and injure the gingivae. Right - oblique position of the bristles on a lower tooth, which makes traumatization of the buccal gingivae possible.
This work is dedicated to the Public Domain.