A dental guard (10) for preventing wear of the occlusal surfaces of a user's teeth resulting from bruxism is provided. The dental guard (10) can be can be custom-fitted to the teeth of the wearer. The guard (10) comprises a durable core (14) that is overmolded by a thermoplastic outer layer (12). The outer layer (12) can be softened through exposure to hot, but not boiling, water, and then formed around the user's teeth. The guard (10) may include one or more features (32, 84) that assist the user in proper positioning of the guard within his or her mouth during the custom fitting process.