Should i leave my baby to cry?

Oh my, please don't let your baby cry himself to sleep. Give him the dummy, it's only natural for babies want to suck on either a dummy, a thumb, a bottle or mummy's . If it bothers you about his teeth you could get the orthodontic types, i used it with my son for 2 years, when he was two we both decided to gather up all his dummies and stick them in the bin. His teeth are perfect. Good luck!