A RARE sloth has been given the all-clear at a recent health check following pioneering dental surgery at Chester Zoo. Images show the moment that Rico, a 25-year-old two-toed sloth, willingly clambered in front of an X-ray machine for a once-over. Keepers were the first to spot that he had swellings on the side of his face. A series of check-ups, including a CT scan, revealed that Rico had two root abscesses.