Centric Relations Research Articles

Centric occlusion and jaw relations and fallacies of current concepts

Centric occlusion and jaw relations and fallacies of current concepts

Some physiologic considerations of centric and other jaw relations

The postural position of the mandible is the only reflex determining mandibular position present at birth. Centric relation is learned after the teeth errupt: it is the first learned reflex determining the occlusal position of the mandible after the primary dentition is complete. Eccentric mandibular positions are learned as expedient mechanisms for avoiding occlusal disharmonies. They are forgotten when the source of the afferent impulses prompting them is removed. Centric relation in the edentulous adult is determined by muscle proprioceptors largely, and thus presents slightly different problems in registration.

The checkbite-impression tray for hydrocolloids in restorative dentistry

1.The acceptable accuracy of reversible hydrocolloid for crown, bridge and inlay impressions is recognized. 2.The accuracy of alginates for the same purpose is questioned. 3.The available die materials are adequate, but should be improved since they are not perfect. 4.Various techniques for the use of the unilateral checkbite-impression tray are described. These include: making a checkbite at the same time the impressions of preparations for single or multiple inlays, three-quarter and full crowns and the edentulous areas for a bridge are made; making a simple checkbite in alginate to be used with dies for inlays and crowns which have been made from separate impressions; recording the correct relations of the parts of a bridge to opposing and adjacent teeth for bridge repairs, and making one piece cast bridges. 5.The anterior checkbite-impression tray and its uses have been described. 6.The full arch checkbite-impression tray for making simultaneous impressions of both arches at the same time the centric jaw relations are recorded has been described. This tray may be used in conjunction with other recording equipment for making casts and mountings for the study of occlusal relations in the various jaw positions. It may also be used for restorative procedures which are being done simultaneously in both arches.

Centric and Functional Bite Relations

Centric and Functional Bite Relations