FIG. 1 is a front perspective view of a portion of a chair back for dental patients.

FIG. 2 is a rear perspective view of the portion of the chair back of FIG. 1.

FIG. 3 is a top view of the portion of the chair back of FIG. 1.

FIG. 4 is a right-side elevational view of the portion of the chair back of FIG. 1. The left-side elevational view is omitted as being a mirror image of the right-side elevational view.

FIG. 5 is a front perspective view of the portion of the chair back for dental patients shown in the context of an exemplary dental chair.

The broken lines in the Figures are for illustrative purposes only and form no part of the claimed design. Additionally, the bottom view is omitted as being devoid of surface ornamentation.