• 대한치과보철학회지
• /
• 제29권2호
• /
• pp.295-317
• /
• 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
• /
• 제15권1호
• /
• pp.11-21
• /
• 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.

• 대한치과보철학회지
• /
• 제46권4호
• /
• pp.420-430
• /
• 2008

연구목적: 기존의 교합기들은 서양인의 악안면구조와 하악운동 평균치에 맞추어 제작되어 있다. 이에 현재 임상교육에 널리 사용하고 있는 반조절성 교합기 (KaVo PROTAR, Hanau Modular)를 한국인에게 적용함에 있어서 적절한 기준을 구하고자 이번 연구를 시행하였다. 연구방법: $24{\sim}41$세 한국인 성인 59명 (남41명, 여18명)을 선정하였다. 피검자 일인당 두쌍의 상하악 모형을 제작, KaVo PROTARevo 7과 Hanau Modular 반조절성교합기에 facebow transfer하여 교합기에 부착 후 전방시상과로각, 교합평면경사도, 교합기 상의 하악의 위치를 계측하였다. 연구성적: 1. 평균 전방시상과로각은 KaVo PROTAR 반조절성 교합기상에서 $33.75^{\circ}$(표준편차 $12.46^{\circ}$)였고, Hanau Modular 반조절성 교합기상에서 $40.72^{\circ}$(표준편차 $12.09^{\circ}$)였다. 2. 평균 교합평면경사각은 KaVo PROTAR 반조절성 교합기상에서 $-2.76^{\circ}$(표준편차 $3.63^{\circ}$)였고, Hanau Modular 반조절성 교합기상에서 $11.87^{\circ}$(표준편차 $3.63^{\circ}$)였다. 3. 하악치열의 중심은 교합기의 중심에서 평균 $5{\sim}7$ mm 범위내에 있었으며 KaVo PROTAR 반조절성 교합기에서는 전치부와 구치부 모두 교합기의 상하적 위치관계에서 중앙에 위치하였고, Hanau Modular 반조절성 교합기에서는 교합기의 중앙높이에서 전치부는 하방 5 mm, 구치부는 상방 3 mm에 위치하였다.

• 대한치과보철학회지
• /
• 제51권3호
• /
• pp.153-159
• /
• 2013

연구 목적: 근래에 들어 체크바이트 법뿐만 아니라 디지털 센서를 이용하여 하악의 운동을 기록, 분석하여 과로각을 계산하는 방법이 개발되어 사용되어져 오고 있으나 두 방법간의 비교하는 연구는 없었다. 이에 새로운 방법인 ARCUSdigma 2 system을 이용한 방법과 전통적인 방법인 체크바이트 법으로 과로각을 측정하여 두 방법 간의 차이를 비교해 보고자 하였다. 연구 대상 및 방법: 교정치료의 경험이 없고, 제3대구치를 제외한 치아의 결손이 없고, 교합평면의 변화를 수반한 광범위한 수복이 없으며, 악관절 질환이 없는 24세부터 34세 사이의 건강한 젊은 성인 남녀(남 10명, 여 10명)를 대상으로 하여 Camper's plane을 기준으로 하여 ARCUSdigma 2 system과 왁스를 사용한 체크바이트법을 각각 3번씩 측정하였으며 교합기는 KaVo Protar Evo 7 반조절성 교합기를 사용하여 각각의 방법으로 과로경사각을 측정하였다. 두 방법 간의 자료를 SPSS 20을 이용한 Mann-Whitney U Test를 사용하여 통계적으로 분석하였다. 결과: 1. ARCUSdigma 2 system에서 전방시상과로각은 좌우 각각 $26.97^{\circ}({\pm}7.38^{\circ})$, $29.80^{\circ}({\pm}8.19^{\circ})$로 측정되었으며, 측방과로경사각은 $5.75^{\circ}({\pm}3.47^{\circ})$와 $8.10^{\circ}({\pm}4.98^{\circ})$로 측정되었다. 2. 체크바이트법에서 전방시상과로각은 좌우 각각 $25.20^{\circ}({\pm}6.53^{\circ})$, $28.18^{\circ}({\pm}7.38^{\circ})$로 측정되었으며, 측방과로경사각은 $10.97^{\circ}({\pm}5.63^{\circ})$와 $12.03^{\circ}({\pm}5.22^{\circ})$로 측정되었다. 결론:두 방법 모두 남녀간 좌우간 유의적 차이는 나타나지 않았으며 두 방법 사이에서는 측방시상과로각에서 ARCUSdigma 2를 사용하여 측정한 값이 Checkbite를 사용하여 측정한 값보다 통계적으로 유의하게 작게 측정되었다(P<.05).

• 대한치과보철학회지
• /
• 제32권2호
• /
• pp.281-295
• /
• 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.

• 대한치과교정학회지
• /
• 제47권5호
• /
• pp.277-288
• /
• 2017

Objective: Treating Class II subdivision malocclusion with asymmetry has been a challenge for orthodontists because of the complicated characteristics of asymmetry. This study aimed to explore the characteristics of dental and skeletal asymmetry in Class II subdivision malocclusion, and to assess the relationship between the condyle-glenoid fossa and first molar. Methods: Cone-beam computed tomographic images of 32 patients with Class II subdivision malocclusion were three-dimensionally reconstructed using the Mimics software. Forty-five anatomic landmarks on the reconstructed structures were selected and 27 linear and angular measurements were performed. Paired-samples t-tests were used to compare the average differences between the Class I and Class II sides; Pearson correlation coefficient (r) was used for analyzing the linear association. Results: The faciolingual crown angulation of the mandibular first molar (p < 0.05), sagittal position of the maxillary and mandibular first molars (p < 0.01), condylar head height (p < 0.01), condylar process height (p < 0.05), and angle of the posterior wall of the articular tubercle and coronal position of the glenoid fossa (p < 0.01) were significantly different between the two sides. The morphology and position of the condyle-glenoid fossa significantly correlated with the three-dimensional changes in the first molar. Conclusions: Asymmetry in the sagittal position of the maxillary and mandibular first molars between the two sides and significant lingual inclination of the mandibular first molar on the Class II side were the dental characteristics of Class II subdivision malocclusion. Condylar morphology and glenoid fossa position asymmetries were the major components of skeletal asymmetry and were well correlated with the three-dimensional position of the first molar.

• Imaging Science in Dentistry
• /
• 제46권2호
• /
• pp.127-131
• /
• 2016

Purpose: This study was performed to compare the condylar position in patients with temporomandibular joint disorders (TMDs) and a normal group by using cone-beam computed tomography (CBCT). Materials and Methods: In the TMD group, 25 patients (5 men and 20 women) were randomly selected among the ones suffering from TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The control group consisted of 25 patients (8 men and 17 women) with normal temporomandibular joints (TMJs) who were referred to the radiology department in order to undergo CBCT scanning for implant treatment in the posterior maxilla. Linear measurements from the superior, anterior, and posterior joint spaces between the condyle and glenoid fossa were made through defined landmarks in the sagittal view. The inclination of articular eminence was also determined. Results: The mean anterior joint space was 2.3 mm in the normal group and 2.8 mm in the TMD group, respectively. The results showed that there was a significant correlation between the superior and posterior joint spaces in both the normal and TMD groups, but it was only in the TMD group that the correlation coefficient among the dimensions of anterior and superior spaces was significant. There was a significant correlation between the inclination of articular eminence and the size of the superior and posterior spaces in the normal group. Conclusion: The average dimension of the anterior joint space was different between the two groups. CBCT could be considered a useful diagnostic imaging modality for TMD patients.

• 대한치과교정학회지
• /
• 제45권3호
• /
• pp.121-129
• /
• 2015

Objective: This study aimed to assess three-dimensional changes in the temporomandibular joint positions and mandibular dimensions after correction of dental factors restricting mandibular growth in patients with Class II division 1 or division 2 malocclusion in the pubertal growth period. Methods: This prospective clinical study included 14 patients each with Class II division 1 (group I) and Class II division 2 (group II) malocclusions. The quad-helix was used for maxillary expansion, while utility arches were used for intrusion (group I) or protrusion and intrusion (group II) of the maxillary incisors. After approximately 2 months of treatment, an adequate maxillary arch width and acceptable maxillary incisor inclination were obtained. The patients were followed for an average of 6 months. Intraoral and extraoral photographs, plaster models, and cone-beam computed tomography (CBCT) images were obtained before and after treatment. Lateral cephalometric and temporomandibular joint measurements were made from the CBCT images. Results: The mandibular dimensions increased in both groups, although mandibular positional changes were also found in group II. There were no differences in the condylar position within the mandibular fossa or the condylar dimensions. The mandibular fossa depth and condylar positions were symmetrical at treatment initiation and completion. Conclusions: Class II malocclusion can be partially corrected by achieving an ideal maxillary arch form, particularly in patients with Class II division 2 malocclusion. Restrictions of the mandible in the transverse or sagittal plane do not affect the temporomandibular joint positions in these patients because of the high adaptability of this joint.