The side of the tooth towards the tongue. The side of the tooth towards the middle of the jaw. The last three upper and lower teeth on both sides of the mouth. A device to be worn in the mouth. Depending on the design of it, it prevents injury to teeth and/or jaw during teeth grinding or sport events. A mouthguard which is worn at night time. The biting surface of the back teeth. The way how the upper and lower teeth close together.