Reproducibility of the centric relation bite registration technique.
Many orthodontists today are using diagnostic casts mounted in centric relation (CR) because they can reveal a completely different malocclusion than what is seen in maximum intercuspation (MI). The CR to MI slide can be measured at the condyles using a semi-adjustable articulator and a condylar position indicator device (CPI). However, before planning treatment from casts mounted in CR, the reliability of the method must be established. Therefore, the purposes of this investigation were: i) to determine the reproducibility, measured with the CPI, of the two-piece wax CR bite registration technique as described by Roth; ii) to determine the direction of the centric slide; iii) to determine differences in overjet measured from CR and MI and; iv) to evaluate the location of the initial tooth contacts in CR. The condylar displacements for 39 subjects were measured in vertical and horizontal components from mounted models. A CR bite registration was taken five times (approximately every five days) and used to remount the lower cast and record the data five times. Since there was not a significant difference between the five CPI readings (p > .05), the Roth CR bite registration is highly reproducible. The condyle moved inferiorly with a small distal component from CR to MI. A statistically significant difference (p < .001) was found in the overjet measurements between CR and MI. Thirty six out of 39 subjects had an initial tooth contact in CR on the most posterior tooth.
Wood
D P
DP
Faculty of Dentistry University of Western Ontario London, Canada.
Elliott
R W
RW
D000328:Adult; D000704:Analysis of Variance; D016302:Centric Relation; D003725:Dental Articulators; D003768:Dental Occlusion, Centric; D005069:Evaluation Studies as Topic; D006801:Humans; D008310:Malocclusion / Q000175:diagnosis; D008335:Mandibular Condyle / Q000502:physiology*; D003765:Models, Dental; D015203:Reproducibility of Results