Do not use: As a sports mouthpiece. The product is designed to absorb top-to-bottom pressure not shock absorption; if you are under 18 years of age; for more than three months without consulting your dentist; if you have loose teeth or teeth that can wiggle; if your dentist has told you that you have temperomandibular joint (TMJ) pain or clicking of the jaw; if you have any pain from teeth grinding or other forms of tooth or jaw pain; if you have dental implants or wear dentures, braces or other dental appliances. Ask a dentist before use if you have: major health problems or serious breathing or respiratory conditions; oral sores, bleeding gums or any gum disease; cavities that have no fillings, or loose fillings or caps; difficulty chewing or pain of the jaw, teeth or face; two or more missing teeth. Stop use and ask a dentist if: you develop soreness, bleeding gums or any other reaction inside your mouth; you develop jaw pain, teeth pain, ear pain, headache, neck stiffness or joint clicking when using this product; the same symptoms persist after over a month of use; the product falls out of your mouth easily; the product disrupts breathing, feels uncomfortable or causes you to gag; you have a change in your bite that persists more than a few minutes after removing this product. See your dentist every six months.