A special night guard, named as “AGP night guard”, comprising a “special retention piece and AGP (Anterior Guidance Package), is provided. The “AGP night guard comprises of; 1) one AGP and 2) two special retention pieces having an anteriorly protruded shelf to receive the maxillary guidance component of the AGP and/or mandibular guidance component of the AGP. For severe Class II malocclusion patient an AGP night guard uses: 1) one AGP, 2) one special retention piece of the current application to receive mandibular guidance component of the AGP and 3) one regular retention piece to apply maxillary guidance component of the AGP. For severe Class III malocclusion patient, the AGP night guard uses; 1) one AGP, 2) one special retention piece of the current application to receive maxillary guidance component of the AGP and 3) one regular retention piece to apply mandibular guidance component of the AGP.