Hi Rachel,
This works for my little one and you could try it. For daytime sleeps only (he doesnt use is at night) he is allowed a dummy to fall asleep with. Once he is asleep, he goes through periods of sucking and not-sucking. During the first not-sucking period (usually within about 5 mins) I pull the dummy out. He doesnt even notice as his mouth hasn't loosened to let the dummy fall out. Generally he then sleeps quite well.
Good luck!