Tissue adaptation will be assessed by 3D laser scanner. The occlusal, facial and lingual surfaces of the upper arch will be scanned as will the inner surface of the night guards. An index of adaptation will be developed based on the volumetric spaces separating the teeth from the device, using topological software. Smaller volumes will represent better tissue adaptation. Volumetric indices will be compared between devices via ANOVA or appropriate statistical methods. Note that a major part of this study will be to develop an accurate and precise way of measuring volumetric spacing, as such methods have not yet been developed.