FIG. 1 is a front perspective view of a head portion of a toothbrush according to the new design;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The broken lines formed by linear segments of equal length are provided for environment only and form no part of the claimed design. The broken lines formed by a dash-dot-dash sequence represent a boundary between claimed and unclaimed subject matter and form no part of the claimed design.