Oral appliances adapted to for spacing the occlusal surfaces of the teeth of a user are disclosed. The oral appliances have a major connector interconnecting a first bite pad and a second bite pad. The first bite pad can include a first spacer and the second bite pad can include a second spacer that are configured to maintain the spacing of the occlusal surfaces of opposing teeth of a user during clenching or upon an impact to the jaw. Methods for the manufacture of composite oral appliances are also disclosed. The methods include forming a composite oral appliance over a model of a users mouth.