Condylar displacement between centric relation and maximum intercuspation in symptomatic and asymptomatic individuals

Abstract

Objective: To measure condylar displacement between centric relation (CR) and maximum intercuspation (MIC) in symptomatic and asymptomatic subjects.

Materials and methods: The sample comprised 70 non-deprogrammed individuals, divided equally into two groups, one symptomatic and the other asymptomatic, grouped according to the research diagnostic criteria for temporomandibular disorders (RDC/TMD). Condylar displacement was measured in three dimensions with the condylar position indicator (CPI) device. Dahlberg's index, intraclass correlation coefficient, repeated measures analysis of variance, analysis of variance, and generalized estimating equations were used for statistical analysis.

Results: A greater magnitude of difference was observed on the vertical plane on the left side in both symptomatic and asymptomatic individuals (P = .033). The symptomatic group presented higher measurements on the transverse plane (P = .015). The percentage of displacement in the mesial direction was significantly higher in the asymptomatic group than in the symptomatic one (P = .049). Both groups presented a significantly higher percentage of mesial direction on the right side than on the left (P = .036). The presence of bilateral condylar displacement (left and right sides) in an inferior and distal direction was significantly greater in symptomatic individuals (P = .012). However, no statistical difference was noted between genders.

Conclusion: Statistically significant differences between CR and MIC were quantifiable at the condylar level in asymptomatic and symptomatic individuals.

Figures

Figure 1

Maximal intercuspation (MIC) wax bite registration was taken with one sheet only of Beauty Pink Wax (Moyco Inc, Philadelphia, Pa).

Figure 2

For the centric relation (CR) bite record, Blue Bite Registration Delar Wax (Delar Corp, Lake Oswego, Ore) was used in two sections according to Roth's power centric technique.

Figure 3

Centric relation (CR) position in condylar position indicator (CPI) instrumentation determined by CR bite record.

Figure 4

Maximal intercuspation (MIC) position in condylar position indicator (CPI) instrumentation determined by MIC bite record.

Figure 5

Centric relation (CR) position was marked in black, and maximal intercuspation (MIC) in red. On the vertical plane, a negative sign represents that MIC is dislocated in the superior direction, and on the horizontal plane, in the posterior direction. A positive sign on the vertical plane indicates inferior direction, and on the horizontal plane, anterior direction.

Figure 6

(A) Right lateral view of models mounted in maximal intercuspation (MIC). (B) Right lateral view of models mounted in centric relation (CR) from the same patient.

Figure 7

(A) Left lateral view of models mounted in maximal intercuspation (MIC). (B) Left lateral view of models mounted in centric relation (CR) from the same patient.