Guided versus unguided mandibular movement for duplicating intraoral eccentric tooth contacts in the articulator

Abstract

Statement of problem. The extent to which intraoral excursive tooth contacts are duplicated correctly in the articulator is constantly being investigated. Purpose. This study evaluated whether data from unguided or guided hinge axis movement are superior in duplicating excursive tooth contacts. Material and methods. Intraoral records of tooth contacts from intercuspal position to 4 mm protrusion and laterotrusion were obtained from 50 subjects by using occlusogram wax. These movements were simulated in a SAM2 “P” articulator using horizontal condylar inclination and Bennett angle from recorded guided and unguided mandibular movements. Occlusograms were compared with contacts generated by the articulator. Results. On average, the articulator duplicated approximately 73% of intraoral protrusive and 81% of intraoral laterotrusive contacts for up to 4 mm of movement, using either data from unguided or guided movements. Both movements yielded identical means and no significant difference of duplicated contacts. However, individual differences scattered within approximately ±32%. Conclusion. Exclusive recommendation of guided movement can be questioned for accurate imitation of dynamic tooth contacts. In addition to the type of movement, other factors must be detected to enhance articulator adjustment and workings. (J Prosthet Dent 1999;81:14-22.)