Whenever I go to the dentist, I'm amazed at the number of specialty instruments and gadgets used to clean and repair teeth. Many of these are patented. According to the USPTO website, 19,194 patents issued since 1790 are classified in Class 433, Dentistry, in addition to 3,742 published applications. (This doesn't include tooth brushes, which are classified in Class 15.)
Related to this is an interesting story in the New York Times about Greene Vardiman Black, the father of modern dentistry. According to the story, in the late 19th century Black pretty much single-handedly transformed dentistry into a modern profession. In the process, he invented dozens of new dental instruments and materials. The story also claims he had little interest in patenting his inventions, which the patent record appears to confirm. A quick search in Google Patents reveals only two patents issued to Black on August 8, 1871, an improvement in dental drills (US117733) and an improvement in universal joints (US117732). He also received a reissue patent for his dental drill (USRE7452) on Jan. 2, 1877.