It's simply a curved hemostat with a 60 degree curve rather than 30 degree, with narrower but thicker working end constructed of a stronger, tougher alloy than conventional hemostats & inlaid with a tungsten-carbide serrated tip for gripping wet glass, such as porcelain restorations. I searched for two years for such an indispensable item in the late 70's before resorting to building one. Strange that someone else didn't do that work years earlier' 'twould be very difficult to practice dentistry without that instrument ... y'see, using "regular" instruments, like hemostats designed to clamp soft things like arteries, is dangerous in dentistry; grabbing a moist, slippery crown or bridge with those instruments can easily squirt it like a watermelon seed down our client's throat. Better to do that in Japan, where there's a lawyer for every 20,000 honest people rather than here, were the ratio is 1:200!
If your dentist does not have one of those instruments in each treatment room, (s)he probably doesn't know the Crown Gripper's available & if it were MY throat involved, I'd direct that dentist to his dental dealer to direct to www.miltex.com to order some, otherwise I'd advise you to keep the back of your mouth sealed securely with your tongue or an old sock & if any dental prostheses get shot in that direction, be sure to swallow them rather than inhale them (there's a back door if you swallow 'em).
That was my first experience with "residual income" and we donated the first ten years of royalties to the American Fund for Dental Health & they're presently being donated to the Carnelian Bay Fund for Lou's Retirement". We've since discovered "REPRODUCIBLE Residual Income". CLICK HERE to learn more