Lower Jaw Movements Measured by Optoelectronic Movement Recording : A pilot study

Abstract: Due to the complex nature of jaw movements, three-dimensional (3D) movement recording provide information about the jaw movement capacity. The aim of the present report was to test the reliability of measuring lower jaw movements using a 3D movement recording system and to calculate the lower jaw movement volume. Lower jaw movements, recorded by 3D optoelectronic movement analysis system (MacReflex®) was compared with reference values from a digital caliper. Pre-tests were performed to develop a software to calculate the lower jaw movements in separate dimensions and its volume. Pilot tests with two test persons followed to register the lower jaw movements and calculate lower jaw movement volume. The results indicate low reliability of lower jaw movements measured by movement recording system compared with reference values from digital caliper, reflected by delta values (D = max-min). The values from the movement recording system indicate high variability reflected by higher levels of standard deviation for movement recorded values compared with digital caliper and by percentage values calculated from the differences between mean values of movement recording and digital caliper. The calculated lower jaw movement volume was 10.3 cm3 and 17.2 cm3 for the test persons, respectively. Conclusively, the results imply that further testing of the method is needed with larger series and test-retest reliability analysis to evaluate the possibility to improve accuracy of tracing jaw movements with recording device. The 3D-movement recording system together with the software could be used for calculation of lower jaw movement volume but its accuracy could not be validated.