An Evaluation of the Mandibular Movements Reproducibility by using Both Pantographic Reproducibility Index and BioEGN Reproducibility Index

하악운동 재현성의 평가에 관한 비교연구

An observation and evaluation of the reproducibility of the mandibular movements has been a integral part of a test for mandibular function and dysfunction. After Pantographic Reproducibility Index(PRI) was introduced in dentistry, many authors have used the index for investigation of mandibular movement function, especially in condylar compartment. Howerer, the difficult and time-consuming work of instrumentation for getting the PRI has been a major obstacle in using pantograph. This study was performed to try a new mandibular reproducibility index, so-called BioEGN reproducibility index(BERI), calculated from mandibular trajectory recorded with BioEGN. 26 dental students without any signs and symptoms of temporomandibular disorders and 22 patients with temporomandibular disorders took part in this study and classed to control group and patients group, respectively. Pantronic and BioEGN were used to record and calculate the indices, PRI and BERI. PRI had only one value, but BERI had two values of outgoing and incoming movement in each scale. With two scales of small and large, as a result, BERI had four values in this study. PRI corresponded to BERI in small scale on outgoing total movements. The data were calculated and analyzed with SAS/stat program and the conclusion of this study were as follows : 1. In every scales, in each movement, BERI on outgoing movement in control group was lower than that in patients group, respectively, but BERI on incoming movement was only different in one side movement, that was, left excursion. 2. The difference between BERI on outgoing movement and BERI on incoming movement was only shown in small scale on total movements, not in each movement, in control group. However, there was generally a positive correlationship between BERI on outgoing movement and BERI on incoming movement in each movement in both groups. 3. Simple statistics of PRI was similar to that of BERI on total movements in small scale, but there was a negative correlation between PRI and BERI on total movements in large sclae only in patients group.