oral sedative and laughing gas

Ma

so my 3 yr old will be getting his front 3 top teeth pulled on the 26th and I'm so scared and nervous for him I didnt know milk was so bad for teeth and even letting him pacify when I breastfed him for 2 yrs was bad too I they will be giving him a oral sedative and laughing gas has anyone else had this done or your kids or anyone yall know?? I feel so horrible