Abstract: An apparatus for protecting and treating teeth including a mouthpiece and storage container is disclosed. The mouthpiece has an arcuate or U-shaped body and is molded from a thin layer of soft, absorbent, and pliable elastomeric material. A continuous U-shaped channel is dimensioned for receiving the upper teeth of a user and is formed in the body in a location adjacent its periphery for a length coextensive with the U-shaped periphery of the body. The body has an integral center portion which arches upwardly from the U-shaped channel to conform to the similarly upwardly arched or convex form of the roof of the mouth or palate of the mouthpiece user. The U-shaped channel may be enclosed and filled with encapsulated setting materials to form a permanent, form-fitting dental impression for the upper teeth of the user. A medicated pad may be adhesively positioned over the enclosed channel to relieve sore gums and teeth.