The ornamental design for a universalposteriortoothxraymarker, as shown and described.
FIG. 1 is a top plan view of my design for a universal posterior tooth xray marker;
FIG. 2 is a left side view thereof; the right side view is a mirror image;
FIG. 3 is a bottom plan view thereof; and,
FIG. 4 is an lower side view thereof; the upper side view is a mirror image.
The details shown in broken lines form no part of the claimed design.
The label is a radio-opaque marker for an incisor is shown on front (FIG. 1). The left and right sides (FIG. 2) and the upper and lower sides (FIG. 4) of the universal posterior tooth xray marker are mirror images of each other. The left, right, upper, lower, and the bottom sides (FIG. 3) bear no markings.