When someone strikes my men, my jaws shut really fast and after that my teeth start to hurt. I'm afraid they're gonna crack or break. Is there something I can do to preserve my smile?
Answer: I think this is a great question. Before asking your kendo mates to strike more softly :), I want you to do the following.
Firstly, you must place your shin on where your chin is supposed to be. Sometimes people put their chin beyond the chin stopper. That will hurt you even more.
Secondly, I want you to check if the men fits you properly. If it is too big and your chin moves when you put your men on then, you should put something on top of the where your chin goes. An easy solution is to put a folded tenugui on the chin of your men.
You must adjust the thickness of your tenugui. Also make it look tidy, please.
Please refer to the video below.
Thirdly, your mouth should be shut when you receive. If your mouth is open when you put a men on, probably your men is too big. Of course, you should be able to open your mouth to have kiai so it has to have some space for that.
It is important to have your mouth shut when receiving.
Now having said that, if you training partners are striking too hard, talk to your sensei. Maybe they are not striking as hard as you think they are.