A. You shouldn’t have to grit your teeth at all. The denture should just fit in to place comfortably and stay there. If your partial doesn’t fit properly then you need to have a new one made. With regards to your other teeth, it is always best to keep your own teeth for as long as possible. If you have them extracted you will regret it because full dentures can be even more difficult to keep in. Also when the back teeth are extracted the bone will shrink back and you can loose a lot of facial support which can age the lower half of the face.
I hope this helps
Kind Regards