Does anyone feel these are too soft where they won't provide proper protection for night time chewers and grinders?

Bob - These are actually tougher than they appear. The light version is the one I use and, as a grinder, they work just fine and I've noticed my teeth don't hurt when I wake up in the middle of the night or in the morning. The kit also comes with a heavy duty version that I would say is on par with sports mouth guards so if the regular version isn't 'heavy' enough I'm pretty sure the heavy duty version will be. Hope this helps.

On the box: "You will also notice your teeth whiten slightly after use." Seller: Is there a chemical in this?

Thank you very much for your inquiry.Our dental appliance doesn't contain any additional chemical components. What we refer to in our advertising is that our product can also serve as a protector used for teeth whitening.

Is it just from the top or the top and the bottom as well?

Thank you very much for your inquiry. Just upper. That's all need for a mouth guard. Just follow the shaping instructions and make sure you bite down firmly when shaping to your teeth. If you have any other questions or needs, please feel free to let us know, and we will be dedicated to assisting you.