• 대한치과기공학회지
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• 제2권1호
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• pp.25-27
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• 1980

In the process of arranging artificial teeth the simple atracing technique was shown to be more precise and convenient for general use in dental clinic than gothic arch tracing. The simple tracing technique had some advantages over other ones in that they were very useful to check protrusive, lateral and central occlusion of mandible movement, and it was very easy to transfer the oral condition and mandible movements precisely onto the articulator. Also the technique was more effective than when using wax bite in that the functional movement range has shifted to 0.2 - 0.4mm form central occlusion.

• 대한치과기공학회지
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• 제20권1호
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• pp.5-11
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• 1998

The purpose of this study is to evaluate the castability and surface roughness of the casts using Non-percious alloys. For samples of 25 wax patterns, it is made from eight layers of sheet wax, arranged in the escalating layers. After fabricated wax patterns, using 5 kinds of Ni-Cr alloys is casted, and the casts are sandblasted. To castability, magnifier is used and values of surface roughness of the casts is measured with profilometer(tracing length 1.75mm, cutoff value 0.25mm) The results are as follows : 1. The castanbility of alloys, in case of C alloys, showed with $8.0{\pm}0.0000$, and in case of CS alloys and N alloys showed equal with $7.8{\pm}0.4472$, respectively. T alloys and V alloys showed equal with $7.2{\pm}0.4472$, respectively. 2. The values of surface roughness of the casts are decreased more T alloys than in case of order alloys, and in order, increased in case of CS alloys, C alloys, V alloys, N alloys, respectively.

• 대한치과보철학회지
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• 제28권2호
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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 Advanced Prosthodontics
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• 제4권3호
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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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• 제6권4호
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• pp.259-265
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• 2014

PURPOSE. The purpose of this study was to develop a dental image processing system using a three-dimensional (3D) camera and stereovision technology. The reliability of the system for measuring axial wall convergence angles was evaluated. MATERIALS AND METHODS. The new system predicted 3D coordinate points from 2D images and calculated distances and angles between points. Two examiners measured axial wall convergence angles for seven artificial abutments using a traditional tracing-based method (TBM) and the stereovision-based method (SVBM). Five wax abutment models of simplified abutment forms were made and axial wall convergence angles of wax models were measured by both methods. The data were statistically analyzed at the level of significance, 0.05. RESULTS. Intraclass correlation coefficients showed excellent intra-examiner and inter-examiner reliabilities for both methods. Bland-Altman plots and paired t-tests showed significant differences between measurements and true values using TBM; differences were not significant with SVBM. CONCLUSION. This study found that the SVBM reflected true angle values more accurately than a TMB and illustrated an example of 3D computer science applied to clinical dentistry.

• 대한치과보철학회지
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• 제58권3호
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• pp.228-238
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• 2020

환자의 교합에 맞춰 적절한 고정성 보철물을 성공적으로 제작 및 수복하기 위해서 필요한 다양한 고려사항이 있다. 그 중 환자가 갖고 있는 교합의 형태를 파악하여 고정성 보철물에 부여하는 것은 필수적이라 할 수 있다. 견치 유도 교합, 군 기능 교합 등 여러가지 교합 형태를 파악하는데 있어서 하악의 운동을 기록하는 것이 중요한데, 1933년 Meyers에 의해 소개된 Functionally generated path (FGP) technique은 구내에서 왁스 등의 재료를 이용하여 교두가 지나가는 하악 운동로를 기록한 후 보철물 제작에 적용하는 치료 술식이다. 본 증례에서는 두 명의 환자에 있어서 상악 구치부에 이차 우식 혹은 치주염으로부터 기원한 치수 유래 병소가 있어, 근관 치료 및 치주 치료 완료 후 고정성 보철물 수복이 필요하였다. 장기적인 예후가 좋지 않은 치아이기에 측방 간섭을 최소화하기 위해 FGP technique을 이용하여 하악 운동을 기록하였다. 통상적인 석고 인상 방법이 아닌 구내 디지털 스캔을 시행함으로써 더 효율적으로 보철물을 제작하였다. 치료 후 환자와 술자 모두 기능적으로 만족할 만한 결과를 얻었기에 이를 보고하는 바이다.

• Anatomy and Cell Biology
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• 제56권2호
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• pp.191-199
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• 2023

The anterior cruciate ligament (ACL) is mostly damaged in sporting activities. To reconstruct the damaged ACL, a patellar tendon (PT) is often the most preferred graft due to its fast healing and bone integration i.e. bone-patellar tendon-bone graft. Suitability of the PT often depends on the morphometric profile of the tendon. This study reported on the harvestable surface area (SA) of the tendon using a simple tracing method. The PT of 79 adult formalin-fixed cadavers of South Africans of European Ancestry were dissected, and the margins of the PT were traced on a wax paper before the tracings were scanned. The SA, straight proximal width (SPW), curved proximal width (CPW), straight distal width (SDW), curved distal width (CDW) and length of tendon (LOT) from the digitized image of the PT was measured. In addition, the length of the lower limbs was measured to normalize the measurements. The results showed no significant side differences, and the measurements were not sexually dimorphic. A strong correlation was reported for SA vs. LOT, SPW vs. CPW and SDW vs. CDW for both sexes and sides. The presented morphological profile provides additional information on the usability of the graft and with respect to healing and recovery.