A comparison of two methods for locating the intercuspal position (ICP) whilst mounting casts on an articulator.

The accuracy of two different techniques for locating casts in the intercuspal position (ICP) in a semi-adjustable articulator was assessed. The techniques for establishing the ICP were a polyether interdental registration, or location of the casts in a position of maximum interdigitation using tactile and visual methods. Fifty-three sets of study models were used in this investigation. Each set of study models was mounted on two occasions, once with each of the two techniques. The models were divided into two groups at random, and mounting and assessment procedures were performed using a single blind crossover design. The quality of the contacts between the mounted casts was compared with the results of an occlusal examination of the same subjects. Hand articulation of the casts prior to mounting the lower cast against the upper cast was a more accurate means of locating the ICP than the use of a low-viscosity polyether interdental registration material, unless there were difficulties in establishing the ICP by visual and tactile methods.