SHARE MORE ABOUT IT. >> TIGERS AND LIONS AND BEARS, OH, MY! >> A SPECIAL 275-POUND ROOT CANAL PATIENT FOR DR. GADDIS. >> AMERICAN BLACK BEAR, 18 1/2 YEARS OLD. >> The Reporter: THREE TEETH TREATED IN THREE HOURS, AS SHE LAID PEACEFULLY ASLEEP WITH HER TONGUE HANGING OUT. >> WAS THERE ANY POINT DURING THE PROCEDURE YOU WERE AFRAID SHE WAS GOING TO WAKE UP? >> NEVER. >> The Reporter: THIS ISN'T THE DOCTOR'S FIRST RODEO. HE'S PERFORMED DENTAL PROCEDURES ON SEVERAL WIDE ANIMALS IN ALPHA PHI ALPHAIVITY, LIKE THE TIGERS, ALSO RIVERET AT THIS, GORILLAS. >> HIPPO WITH A TEAM OF FOLKS AND AN ELEPHANT WITH A TEAM OF FOLKS. THE SMALLEST WAS A FRUIT BAT. >> The Reporter: IN YOU'VE EVER HAD A ROOT CANAL, YOU CAN IMAGINE WHAT YUM-YUM IS GOING THROUGH. HERE'S A LOOK AT THE TEETH NEEDING TREATMENT. THE PROCEDURE ACTUALLY QUITE SIMILAR TO A HUMAN. THE TOOLS, A LITTLE BIT DIFFERENT. THIS VILE, ABOUT THE SIZE USED FOR A HUMAN ROOT CANAL. THIS ONE, FOR A BEAR. >> IT JUST ROTATES. IT JUST SPINS. AND SO THAT'S ABOUT HOW MUCH, 8 TO 50 MILL MITERS, THAT'S HOW LONG THE ROOT WAS IN THE BEAR. >> The Reporter: THE END RESULT -- A MUCH HAPPIER, HEALTHIER, AND MORE COMFORTABLE YUM-YUM AFTER WALKING UP. >> OF COURSE, WE WISH YUM-YUM THE BEST WISHES ON HER RECOVERY IN THE MONTGOMERY COUNTY ZOO. I'M SURE SHE'S A LOT MORE COMFORTABLE. NOW IT'S REALLY INTERESTING, TALKING TO THE DOCTOR AND JUST, YOU KNOW, ANOTHER WALK IN THE PARK. IAN: AND THE RANGE OF ANIMALS THAT HE HAS HELPED WITH DENTAL PROBLEMS OVER THE YEARS AND YOU ASKED THE QUESTION, I WAS WONDERING WHAT, IF YUM-YUM WOKE UP. I WAS CONCERNED ABOUT, DO THEY EVER WAKE UP, BUT HE SAID, HEY, HE WASN'T CONCERNED. >> HE SAID I WOULD BE THE FIRST TO KNOW. YOU WOULD SEE THE MOUTH STARTING TO OPEN