FIG. 1 is a front view of a toothbrush head in accordance with my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a right side view thereof, the left side view being identical;
FIG. 4 is an enlarged top view thereof;
FIG. 5 is an enlarged bottom view thereof;
FIG. 6 is another front view thereof, shown with a sliding brush retainer element in a raised position with a brush head in a configuration of use;
FIG. 7 is a rear view thereof corresponding to the configuration in FIG. 6;
FIG. 8 is a right side view thereof, shown with a sliding brush retainer element in a raised position and with another brush head in a configuration of use, the left side view being identical;
FIG. 9 is an enlarged top view thereof; and,
FIG. 10 is an enlarged bottom view thereof.
The broken lines illustrate portions of he toothbush head that form no part of the claimed design.