Dental instrument for optimal positioning of an X-ray film support

In a dental instrument for positioning of an X-ray film for X-raying of teeth or adjacent tissues, said dental instrument comprising an X-ray film support, a bite block integral with said film support and extending to one side thereof and generally perpendicular thereto to the plane of the X-ray film supported thereby, and an alignment rod coupled to said bite block for adjusting the position of the bite block relative to the film support, the improvement wherein said bite block comprises:

• upper and lower flat plate portions spaced from each other, forming a gap,
• one of said portions being integral with said film support extending outwardly therefrom and generally perpendicular to the plane of the X-ray film,
• the other portion being generally parallel to said one portion, and
• means for pivotably connecting said upper and lower plate portions at said gap for pivoting about an axis perpendicular to the plane of the X-ray film, and the plane of bite defined by the tooth rows contacting the top of the upper plate portion and the bottom of the lower plate portion of the bite block,
• and wherein the plate portion of said bite block not integral with the film support, is free of said other portion except at said pivot connection therebetween, permitting the two plate portions to automatically assume such angular positions that each of them is parallel with a plane through the chewing surfaces of the adjacent tooth row to insure that once the teeth have been clamped to the bite block plate portions, the bite block and the X-ray film support are securely retained in the position selected by the dentist.