I bought a Gameboy with games off of Craig's List at a highly discounted price. As soon as patients sit in the chair, the dental assistant gives the patient the Gameboy and lets the patient select a game. The patient stops playing during the injection and resumes immediately after the injection. I read an article that habitual users actually experience a dopamine release while playing the games and their pain perception dinimshes. I don't know how true that is but I have noticed that the patients who play games on the Gameboy have a more enjoyable visit. It could be a dopamine release or it could be that they are distracted.