cross sectional view of the finished mouth guard the pressure of the user 39 s teeth on the bag forces the uncured polymerizing resin into the spaces between the row of teeth and the inside wall of the dental tray hence once the resin is cured this confirmation gives rise to the formation of the frontal and lateral walls of the mouth guard and its overall final shape the thickness of the biting surfaces as well as that of the frontal and lateral wall depends on the dimensions of the bag and the amount of resin used in the bag the thus formed mouth guard will lessen the risk of injury to the anterior maxillary teeth lessen the risk of jaw fracture and reduce the severity of craniofacial injuries such as damage to the tmj temperomandibular joint the above description is just one specific embodiment of a method for forming the mouth guard of the present invention in practice certain steps such as evenly distributing the resin throughout the bag can be omitted and other steps could be added the steps can also be performed in any order as long as a cured mouth guard is obtained as the final product the method is exemplary only and is not meant to limit the invention in any way a 0 8 mil clear pe sandwich bag was used as the container starting material the sandwich bag was laid flat onto a sheet of paper and a very hot wire which was bent to the shape corresponding to the contour of the desired u shape was impressed onto the bag the.