A dual arch dental appliance including a body which contains a pair of impact absorbing members located in molar regions of the arches. The impact absorbing members are selected from plastic material that exhibits high impact absorption coupled with low resilience or rebound. The result is an appliance which transfers minimal shock to the wearer. The appliance preferably further includes a bumper for providing enhanced impact protection to all of the user's upper and lower teeth. An airway opening is preferably provided to facilitate breathing when the appliance is clenched between the teeth. A post may be provided for structural reinforcement of the airway opening and, optionally, for receiving a tether for fastening the device to a helmet.