• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.43-53
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• 1991

It is important to harmonize the occlusion with TMJ and neuromuscular system. However, clinically, how to harmonize is very difficult. The mandibular movement is the motion in which all component part of stomatognathic system participate. This study was performed to compare mandibular movement of mandibular prognathic patients group with that of normal group, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Thirteen adult who have physiologically normal occlusion and are free of TMJ dysfunction were selected as a control group(Group 1). Eight adult who are mandibular prognathic patient and have more than four anterior teeth crossbite, therefore have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). Electronic pantograph, Denar Pantronic (Denar Corp., U.SA.), was used to record mandibular movement. Pantronic survey was performed by using an arbitrary hinge axis according to manufacturer's direction. Of the Pantronic recordings, immediate side shift (ISS), progressive side shift (PSS), orbiting condylar path (ORB), protrusive condylar path (PRO) between two groups were compared and analysed. The results were as follows: 1. The average protrusive and orbiting condylar inclination of mandibular prognathic patient$(28.44^{\circ},\;36.94^{\circ})$ was significantly lower than those of normal group$(40.15^{\circ},\;48.00^{\circ})$ (P<0.01). 2. There was no statistically significant difference between .the average immediate and progressive side shift of mandibular prognathic patient $(0.37mm,\;6.19^{\circ})$ and those of normal group$(0.52mm.\;5.96^{\circ})$ (P>0.01). 3. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.

• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.7-24
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• 1988

The stable occlusion in function is thought as important as the esthetics in form, in order to preserve the healthy oral condition. The stable occlusion requires the harmony between the condylar guidance factors and the anterior guidance factors. The aim of this study was to evaluate the quantitative relationship between the condylar guidance factors and the anterior guidance factors, estimating statistically the measurement of the condylar paths by Pantronic and those of the anterior guidance factors, craniofacial morphology by roentgenocephalometry in 46 relatively good functional occlusion. The results of this study were as follows. 1. The measurements of the protrusive condylar path inclinations were $36.41^{\circ}$ in the right, $35.63^{\circ}$ in the left, $36.28^{\circ}$ in the mean. The measurements of Fisher's angles were $8.17^{\circ}$ in the right, $6.43^{\circ}$ in the left, $6.87^{\circ}$ in the mean. 2. The anterior facial height and the lower anterior facial height made a negative correlation with the protrusive condylar path inclination. 3. The articular eminence angle relative to the artificial articulator plane showed a positive correlation with the maximum protrusive condylar path. 4. SNA and SNB made a negative correlation with the articular eminence angle, and AAP-GoMe, AAP-DcGn, the facial height ratio had a positive correlation with the articular eminence angle. 5. The angulation of maxillary incisor lingual slope, overbite and the ratio of overbite to overiet showed a positive correlation with the articular eminence angle. 6. The angulation of maxillary incisor lingual slope , overbite, and the ratio of overbite to overjet made a positive correlation with the inclination of occlusal plane, functional occlusal plane. 7. Overbite and the ratio of overbite to overjet had a positive correlation with the angulation of maxillary incisor lingual slope. 8. The anterior guidance factors were more influenced by the mean protrusive condylar path inclination and the maximum Fisher's angle, and the regression equations of those were made.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.125-146
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• 1990

The relationale for recording mandibular movement is to accurately adjust an articulator. Techniques to record mandibular movement include radiographic interpretation, extraoral tracing, and intraoral recording materials. This study was performed to compare the concylar guidance inclination and Bennett shift(immediate & progressive side shift)obtained by using an electronic pantograph, pantograph and wax interocclusal records in Korean. Ten adults who have normal occlusion and are free of TMJ dysfunction were selected and clutches were constructed. At first Pantronic survey was performed three times by using an kinematic hinge axis according to manufacturer's direction. Next pantographic survey was performed three times and the articulator was adjusted with each pantographic recording. And then maxillary cast was attached to the articulator with pantographic as a face-bow and the mandibular cast was mounted to the articulator with centric relation record. Three protrusive, three left lateral and three right lateral wax interocclusal records were taken on the subjects and the articulator was adjusted with each interocclusal record. Protrusive condylar inclination, lateral condylar inclination, immediate side shift and progressive side shift obtained by using electronic pantograph, pantograph and wax interocclusal record were compared and analized. The results were as follows; 1. The average left and right protrusive and orbiting condylar inclination($33.7^{\circ},\;37.1^{\circ},\;40.6^{\circ},\;43.5^{\circ}$) record with Pantronic was significantly greater than that recorded with other methods. 2. The average left and right protrusive and orbiting condylar inclination($24.8^{\circ},\;27.0^{\circ},\;31.4^{\circ},\;32.4^{\circ}$)recorded with wax interocclusal record was less than that of other methods. 3. The average left and right immediate side shift(0.57mm,0.44mm)recorded with wax interocclusal record was greater than that of other methods and the average left rigtht immmediate side shift(0.30mm,0.41mm)recorded with Pantronic was significantly greater than that recorded with pantograph(0.11mm,0.20mm). 4. The average variance of wax interocclusal was signivicantly higher than that of other methods.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.281-295
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• 1994

It is very important for the ideal restorations of anterior openbite patients to record the mandibular movement and to harmonize mandibular movement with other organs in stomatognathic systems. This study was designed to compare the mandibular movement of anterior openbite patients with that of normal bite(Angle Class I) patients, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Saphon Visi-trainer Model 3(Tokyo Shizaisha Co. Japan) and Denar Pantronic(Denar Corp.,U.S.A.) were used to record mandibular movement. Pantronic survey was peformed by using an arbitrary hinge axis according to manufacturer's direction. Twenty-eight adult who have physiologically normal occlusion(Angle Class I) and are free of TM dysfunction were selected as a control group(Group 1). Fifteen adult who are anterior openbite patient and have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). The results are as follows : 1. There was no statistically significant difference between the average immediate and progressive side shift of anterior openbite patients(0.54mm, $7.57^{\circ}$) and those of normal group(0.49mm, $5.96^{\circ}$). 2. The average protrusive and orbiting condylar inclination of anterior openbite patient$(30.87^{\circ},\;32.27^{\circ})$ were significantly lower than those of normal group$(36.11^{\circ},\;39.04^{\circ})$ (P<0.05). 3. In the results of Visi-trainer recordings, the mean for the maximum protrusion, the maximum laterotrusion, the angle of laterotrusion and the angle of protrusion in the horizontal trajectory between group 1 and 2 did not differ significantly. 4. The mean for the angle of protrusion, the maximum opening in the frontal trajectory, the ICP-RCP(A-P) distance and the angle of protrusion in the sagittal trajectory differ significantly(P<0.05). 5. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.295-317
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• 1991

The discrepancy between centric relation and centric occlusion have a great role on the successful prosthodontic and occlusal treatment. This study was performed to investigate the effect of the discrepancy between centric relation and centric occlusion on condylar guidance inclination and Bennett shift (immediate and progressive side shift). Sixteen adults who have physiologically normal occlusion and are free of TMJ dysfunction were selected. The amount of the sagittal CR-CO discrepancy in lower anterior incisor was obtained by Saphon Visi-Trainer. The amount of the CR-CO discrepancy in condylar level was measured on the individualized corrected tomography. Pantronic survey was performed by using a arbitrary hinge axis according to manufacturer's direction. All subjects were divided into two groups, group I (small) and group II (large), according to the amount of CR-CO discrepancy. At first the amount of the CR-CO discrepancy in condylar level between two groups was compared and then the condylar guidance inclination and Bennett shift between two groups were compared and analyzed. The results were as follows; 1. The average CR-CO discrepancy in lower anterior incisors was 0.7mm superoinferiorly, 0.49mm anteroposteriorly, and 0.88 mm in total. The average CR-CO discrepancy in condylar level was 0.43mm. 2. The CR-CO discrepancy measured on teeth level and condylar level were highly correlated (p<0.01). 3. The correlation of the condylar position in the glenoid fossa between two groups was not statistically significant. 4. The large CR-CO discrepancy group showed greater amount of Bennett shift and condylar guidance inclination, but there is no statistical significancy. 5. It seems that the CR-CO discrepancy have greater effect on progressive side shift than other elements of mandibular movements.

• The Journal of Advanced Prosthodontics
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• v.4 no.3
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• pp.153-157
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• 2012

PURPOSE. The study was conducted to compare the radiographic and clinical methods of measuring the horizontal condylar guidance (HCG) values. MATERIALS AND METHODS. The condylar guidance was measured using the radiographic (CT scan) and three clinical methods i.e. the wax protrusive records, Lucia jig record and intraoral central bearing device in 12 patients aged between 20-40 years irrespective of sex. The records were taken and transferred on the semi-adjustable articulator to record the HCG values. The CT scan was taken for 3D reconstruction of the mid facial region. Frankfort horizontal plane (FHP) and a line extending from the superior anterior most point on the glenoid fossa to the most convex point on the apex of articular eminence (AE) was marked on the CT scan. An angle between these two lines was measured on both right and left sides to obtain condylar inclination angle. Three interocclusal protrusive wax and jig records were taken and transferred to the semi adjustable articulator. Three readings were recorded on each side. Similarly the records were taken and transferred to the same articulator using the intra oral central bearing device to record the readings. RESULTS. The statistical analysis showed insignificant differences in the HCG values between the right and left sides [(P=.589 (CT), P=.928 (wax), P=.625 (jig), P=.886 (tracer)]. The clinical methods provided low Pearsons correlation values [(R = 0.423 (wax), R = 0.354 (jig), R = 0.265 (tracer)] for the right as well as the left sides when compared with the CT values. Among the clinical methods, jig and wax method showed strong level of association which is statistically significant while the intra-oral tracer showed weak association with the other two methods. CONCLUSION. The right and left HCG values were almost similar. The CT scan showed higher HCG values than the clinical methods and among the clinical methods, values obtained from all the methods were comparable.

• The Journal of Advanced Prosthodontics
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• v.15 no.1
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• pp.11-21
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• 2023

PURPOSE. To compare the sagittal condylar inclination (SCI) in dentate individuals measured by the different methods with mechanical articulator (MA), virtual articulator (VA), and a jaw tracking device (JTD) system. MATERIALS AND METHODS. A total of 22 healthy dentate participants were enrolled in this study. For MA workflow, the SCI was obtained by a semi-adjustable articulator with protrusive interocclusal records. The SCI was also set on a VA by aligning intraoral scan (IOS) with cone beam computed tomography (CBCT) and facial scan (FS), respectively. These virtual workflows were conducted in a dental design software, namely VAI_OS-CBCT and VAI_OS-FS. Meanwhile, a JTD system was also utilized to perform the measurement. Intraclass correlation was used to assess the repeatability within workflows. The bilateral SCI values were compared by Wilcoxon matched-pairs signed rank test for each workflow, and Kruskal-Wallis test and post hoc p-value Bonferroni correction were used to compare the differences among four workflows. The agreement of VAI_OS-CBCT, VAI_OS-FS, and JTD compared with MA was evaluated by Bland-Altman analysis. RESULTS. Intraclass correlation of the SCI revealed a high degree of repeatability for each workflow. There were no significant differences between the left and right sides (P > .05), except for VAI_OS-CBCT (P = .028). Significant differences were not found between MA and VAI_OS-FS (P > .05). Bland-Altman plots indicated VAI_OS-CBCT, VAI_OS-FS, and JTD were considered to substitute MA with high 95% limits of agreement. CONCLUSION. The workflow of VAI_OS-FS provided an alternative approach to measure the SCI compared with MA.