Abstract: A headrest tilting mechanism includes a curved bar having first and second ends, with a headrest mounting portion proximate the first end and a cam following means proximate the second end. A support means includes a curved cam surface which is engaged by said cam following means, and a pin. The pin slidably engages a portion of the bar which is intermediate the first and second ends so as to allow said bar to be slidable with respect to said support means. The cam following means causes the second end to follow the cam surface of the support means when said bar is slid with respect to said support means. With this arrangement, the curved cam surface is not located at the very top of the chair back and therefore the head of the patient can be significantly closer to the lap of the dentist than prior art arrangements. Furthermore, due to the curvature of the bar, the degree of curvature of the cam following surface can be reduced.

Abstract: An adjustable headrest particularly adapted for a dental, medical or the like treatment chair wherein it is necessary to have a patient's head in various positions. A supporting arm preferably of the four-bar linkage type having a first end for being pivotally mounted on any suitable support for attachment to a treatment chair and a second end being pivotally mounted on a headrest for movement of the headrest which approximates the normal motion of the patient's head. Locking mechanism is attached to the headrest and supporting arm to lock the headrest in any desired position with the use of one hand of the operator.