Shawn Sarver took a deep breath and stared at the bottle of Listerine on the counter. “A minty fresh feeling for your mouth... cures bad breath,” he repeated to himself, as the scalpel sliced open his ring finger. His left arm was stretched out on the operating table, his sleeve rolled up past the elbow, revealing his first tattoo, the Air Force insignia he got at age 18, a few weeks after graduating from high school. Sarver was trying a technique he learned in the military to block out the pain, since it was illegal to administer anesthetic for his procedure.