This set was found a general store in California. It was used in a dentist office for patients to watch TV while being worked on. The lever on the CRT holder is probably to tilt the tube to make the image upright to the patient.
Jim Wall at the Museum of American Heritage sent us this:
Recently we were able to acquire the DentaVision television that you have the picture of on your website. Now that I have been able to look at it closely, and do some research, I have some updated information for you.
The original DentaVision received a design patent in 1960 (D187,819), as a television on a boom. The patent drawing matches the only original photograph of a DentaVision that I can find. I have attached this 1959 image. The DentaVision that was up for auction in 2008 mentions that it has a 32" boom, but is disassembled. I have no idea what ever happened to this particular item since it didn't sell.
All the other Internet images of the DentaVision are from the unit in the JimTown store in Northern California which is the one we now have. The picture tube is mounted directly above the chassis, without a boom. I suspect this was modified at one time to look like this. The wiring inside is consistent with it being rewired at some time.
The television hardware is a Setchell Carlson Model 260 (The DentaVision model is also listed on a paper tag as a Model 260). The picture tube looks to be a Sylvania 5AXP4 with a Merit MDF-70 Deflection Yoke. The chassis cabinet is made out of wood, and the picture tube housing is plastic.
I hope this helps fill out your information on this unusual television. Feel free to ask if you have any questions or to pass our museum email (mail@moah.org ) on to anyone inquiring about the DentaVision.