You can use a q-tip to help open her mouth. Has always worked well for me. If you have not checked inside her mouth much and are a little uncomfortable doing it there are some good videos that can help. Only recommendation i would make; do it with really good lighting. can be a pain in the butt if you’re not experienced and when you do get her mouth open and have a good look...you want the lighting to be good to make your efforts worthwhile.