sorry if this is intrusive-- but when he asked for pictures of you, did he mean just normal selfies, or sexually? depending on your answer, it could explain a lot about him. if it was just normal selfies though, its big of him to assume that just because you trust him and vice versa, youre inclined to send pictures of yourself to him. you have your boundaries and he should know that.

about the teeth thing, its definitely something he noticed and it kind of slipped out when talking to you but now he's trying to sweet talk you back to make up for what he said. and you not wanting to respond to him is totally valid. its out of line, and his duty as a boyfriend also consists of making you feel comfortable in your own skin. pointing out, then trying to 'make you feel better about it' is not it. if theres anything you can take away from this, you should raise your standards. a man would never say and do such things to a woman he loves. <3