A performance enhancing and force absorbing dental appliance adapted to lie within the mouth of an athlete having an occlusal posterior pad made of quadruple composite material comprising four layers of distinct materials, further having a first layer of a durable, resilient material; a second layer of non-softenable, flexible material; a third layer of a hard, very durable material; and a fourth layer of a softenable material, engageable with the occlusal surfaces to space apart the upper and lower teeth, to absorb shock and clenching stress. An adjustable arch adapted to expand and contract to be molded to the palate is provided connecting the posterior pads together within the mouth and out of the way of the tongue to maintain the position of the occlusal posterior pads within the mouth during use and to prevent loss of the pads such as by swallowing. An expandable serpentine bridge may be embedded in the arch.