04010509 is referenced by 107 patents and cites 5 patents.

The invention is a double sulcus toothbrush having two groups of sulcus bristles which diverge at an angle relative to one another laterally of the toothbrush so that these groups may bear against the upper and lower teeth, inside or out, with the bristles entering the sulci at an angle appropriate for their cleansing, these bristles being optionally forwardly inclined, cut at a taper to facilitate brushing of the rear sulci or separated by a group of conventional bristles which are shorter than the sulcus bristles for brushing the crowns of the teeth.

Title
Double sulcus toothbrush
Application Number
635245
Publication Number
4010509
Application Date
January 9, 1976
Publication Date
March 8, 1977
Inventor
Frederic G Huish
3771 Ingraham St., San Diego, 92109
CA, US
IPC
A46B 9/04
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