Absolutely not!
Your molars can chew way harder and tougher things than JAWLINER.
BUT be careful there are a lot of other jaw trainer which are definitely not good for your teeth, especially for your incisors.
For more detailed information, just check our new article: https://jawliner.de/pages/is-jawliner-really-dangerous
If you are still not sure and you generally want to put less pressure on your jaw muscles and train more of your entire facial muscles, we recommend the JAWLINER Fitness Chewing Gum instead of the JAWLINER.