• Title/Summary/Keyword: 치아 구조

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Image Segmentation of Fuzzy Deep Learning using Fuzzy Logic (퍼지 논리를 이용한 퍼지 딥러닝 영상 분할)

  • Jongjin Park
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.5
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    • pp.71-76
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    • 2023
  • In this paper, we propose a fuzzy U-Net, a fuzzy deep learning model that applies fuzzy logic to improve performance in image segmentation using deep learning. Fuzzy modules using fuzzy logic were combined with U-Net, a deep learning model that showed excellent performance in image segmentation, and various types of fuzzy modules were simulated. The fuzzy module of the proposed deep learning model learns intrinsic and complex rules between feature maps of images and corresponding segmentation results. To this end, the superiority of the proposed method was demonstrated by applying it to dental CBCT data. As a result of the simulation, it can be seen that the performance of the ADD-RELU fuzzy module structure of the model using the addition skip connection in the proposed fuzzy U-Net is 0.7928 for the test dataset and the best.

Ab Initio Studies on Proton Affinities of Substituted Thiazoles (치환 티아졸의 양성자 친화도에 대한 Ab Initio 연구)

  • Lee, Gap Yong;Lee, Hyun Mee
    • Journal of the Korean Chemical Society
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    • v.42 no.1
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    • pp.1-8
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    • 1998
  • Molecular electrostatic potential (MEP) of the thiazole, relevant to the binding of lexitroposin that contains thiazole ring to the base pair of minor groove of DNA is obtained from the results of ab initio calculation. The geometry optimization for the two possible conformations of protonated thiazoles is performed with the aid of MNDO and ab initio calculations. The proton affinities are calculated at the 6-31G and 6-31G basis set for the optimized geometry. The proton affinities are also studied for various substituted thiazoles with the electron-donating and electron-withdrawing groups to estimate substituent effect on the proton affinity of thiazoles. It is found that the thiazole with nitrogen atom aligned inward to the DNA minor groove exhibit higher proton affinity and electron-donating substituents increase the proton affinity of thiazoles.ĀȀꃏ?⨀缾ĀȀ會ĀȀ?⨀ꖓĀĀȀ會ĀȀ僐?⨀聥ꖓĀĀȀ會ĀȀ꣐?⨀聐缾ĀȀ會ĀȀÑ?⨀ၑ缾ĀȀ會ĀȀ壑?⨀ꁑ缾ᨀĀꀏ會Āꀏ냑?⨀⡒缾᐀Āꀏ會Āꀏ࣒?⨀끒缾ᰀĀꀏ會Āꀏ惒?⨀ꁩꖓȀĀꀏ會Āꀏ룒?⨀⡪ꖓሀĀꀏ會Āꀏდ?⨀ᤐ돀삺?⨀塨?⨀飣?⨀돐룣?⨀偠잖⨀샣?⨀줏덐탣?⨀젏ꠏܞȌ蠀ᥲ⴯ͧMolecua及컲ࡔȏᰗۊऀںMolecular electrostatic potential (MEP) of the thiazole, relevant to the binding of lexitroposin that contains thiazole ring to the base pair of minor groove of DNA is obtained from the results of ab initio calculation. The geometry optimization for the two possible conformations of protonated thiazoles

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Surgical Evaluation of Endodontic Treatments for Apicoectomy According to Alveolar Bone Resorption Types (치조골흡수 유형에 따른 치근단 절제술의 수술적 평가에 관한 연구)

  • Hong, Hyoung Taek;Chun, Heoung Jae
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.26 no.6
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    • pp.471-474
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    • 2013
  • The surgical evaluation of the apicoectomy with various types of alveolar bone resorption was conducted in current study. The apicoectomy is the common and important treatment in endodontics. Finite element analysis was used for evaluation. The 3D solid model of the maxillary central incisor was reconstructed using CT images of a mature Asian female. Loading and boundary conditions were simulated in the normal mastication of maxillary central incisor. For evaluation of apicoectomy, lingual, labial and entire alveolar bone resorption models were developed. In the results, lingual alveolar bone resorption did not significantly influence stress distribution pattern of root dentin and labial alveolar bone had an important role for supporting structural stability in tooth system.

Fabrication of CAD-CAM complete denture using existing provisional denture and digital facebow transfer (기존 임시의치와 디지털 안궁이전을 이용하여 상하악 CAD-CAM 총의치 수복 증례)

  • Jaehyeok Ro;Haemin Bang;Sangwon Park;Hyun-Pil Lim;Kwi-Dug Yun;Chan Park
    • The Journal of Korean Academy of Prosthodontics
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    • v.61 no.4
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    • pp.268-274
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    • 2023
  • In this case, a CAD-CAM complete denture that can be easily remanufactured and reduced the number of visits was decided in consideration of the fact that it was difficult to visit the dental hospital and many existing dentures were lost because the patient was inpatient in a nursing hospital. In order to reflect the shape, vertical dimension, and maxillomandibular relationship of the existing provisional dentures adapted by the patient to the fabrication of the final denture, the existing provisional dentures were scanned and closed mouth impression was taken with the printed individual tray. After digital facebow transfer using UTS CAD and arranging artificial teeth in CAD software, the maxillary and mandibular complete dentures were fabricated by milling the denture base and artificial teeth at once with the monolithic disc.

Recent Advances in 3D/4D Printed Electronics and Biomedical Applications (3D/4D 프린트된 전자기기 및 바이오메디컬 응용기술의 최근 발전)

  • Hyojun Lee;Daehoon Han
    • Journal of the Microelectronics and Packaging Society
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    • v.30 no.4
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    • pp.1-7
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    • 2023
  • The ability of 3D/4D printing technology to create arbitrary 3D structures provides a greater degree of freedom in the design of printed structures. This capability has influenced the field of electronics and biomedical applications by enabling the trends of device miniaturization, customization, and personalization. Here, the current state-of-the-art knowledge of 3D printed electronics and biomedical applications with the unique and unusual properties enabled by 3D/4D printing is reviewed. Specifically, the review encompasses emerging areas involving recyclable and degradable electronics, metamaterial-based pressure sensor, fully printed portable photodetector, biocompatible and high-strength teeth, bioinspired microneedle, and transformable tube array for 3D cell culture and histology.

The Effect of Drinking Water Fluoride on the Fine Structure of the Ameloblast in the Fetal Rat (음용수 불소가 흰쥐태아 법랑모세포의 미세구조에 미치는 영향)

  • Lim, Do-Seon;Jeong, Moon-Jin;Yoe, Sung-Moon
    • Applied Microscopy
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    • v.29 no.2
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    • pp.189-193
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    • 1999
  • The response of ameloblast to long term (3 weeks) exposure to fluoride was examined in continuously erupting mandibular incisors of pregnancy rats as compared to control rats receiving a similar diet (Teklad L-356) but no sodium fluoride in there drinking water. Rats were started on water containing 0 ppm, 100 ppm, 200 ppm, and 300 ppm NaF at the beginning of pregnancy. To examine on the ultrastructural changes of the ameloblast, electron microscopy was used. The results indicated that rat incisors expressed two major changes in normal amelogenesis that could be attributed to chronic fluoride treatment. The fluoride produces marked alteration in the fine structure of ameloblast from teeth of young rats, such as large confluent distensions of the endoplasmic reticulum and swelling of isolated mitochondria, in particular on the morphology of the rough-surfaced endoplasmic reticulum. A graded series of alterations to these organelles were produced, and the severity of the changes would seem to be dependent on dose and time. This experimental data suggested that exposure prolonged of animal to high level of fluoride appears to induce morphological changes in the normal appositional growth and initial mineralization of enamel created during amelogenesis.

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Full-mouth rehabilitation with implant-supported fixed dental prostheses for the edentulous maxilla and partially edentulous mandible: A case report (상악 완전 무치악 및 하악 부분 무치악 환자에서 임플란트 지지형 고정성 보철물을 이용한 전악 수복 증례 보고)

  • Kim, Tae-Hyung;Oh, Kyung-Chul;Moon, Hong-Seok
    • The Journal of Korean Academy of Prosthodontics
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    • v.57 no.4
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    • pp.374-381
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    • 2019
  • A conventional approach for the treatment of long-span edentulous areas is the use of removable dentures. However, placing implants in these areas results in superior functional outcomes by increasing the stability, support, and resistance of the prostheses and improving the masticatory efficiency. Treatment modalities utilizing implants can be further classified into either removable or fixed-type prostheses. Several factors such as the amount of alveolar bone resorption, inter-arch relationship, patient preferences, and socioeconomic status should be considered when determining the appropriate treatment approach. Monolithic zirconia has been considered a suitable material for implant-supported fixed dental prosthesis, because of the drastic improvement in its mechanical properties. It exhibits fewer incidences of fracture and chipping of the prostheses, and has greater bulk of material than metal-ceramic crowns and zirconia-veneered ceramics. Moreover, highly translucent monolithic zirconia is also available in the market, and its application is gradually increasing for anterior tooth rehabilitation. The present report describes a patient who underwent full-mouth rehabilitation with fixed dental prostheses (eight upper and three lower implant placements). All teeth, except bilateral mandibular canines and left mandibular first and second premolars, were extracted after the diagnosis of generalized chronic moderate-to-advanced periodontitis of the remaining teeth. The patient reported satisfactory esthetic and functional outcomes during the one-year follow-up visit.

The relationship between posterior dental compensation and skeletal discrepancy in class III malocclusion (골격성 III급 부정교합자의 악골 부조화가 구치부 치성보상에 미치는 영향)

  • Sung, Ji-Hyun;Son, Woo-Sung;Kim, Sung-Sik
    • The korean journal of orthodontics
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    • v.33 no.1 s.96
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    • pp.41-49
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    • 2003
  • This study examined the relations between degree of posterior dental compensation and skeletal discrepancy in Class III malocclusion. The pretreatment lateral cephalogras and dental casts of 87 skeletal Class III adults were selected to provide a random sampling of skeletal Class III malocclusion. Skeletal discrepancy was described with ANB angle, Wits appraisal, SN-Mn plane angle, FMA and ratios of basal arch width. Degree of posterior dental compensation was described with maxillary intermolar angle, mandibular interolar angle and sum of intermoloar angle. The relationships between skeletal discrepancy and degree of posterior dental compensation were analyzed with simple correlation analysis, stepwise multiple regression analysis. The results were as follows 1. A strong association was found between the variation in the anteroposterior measure, ANB angle and the variation of posterior dental compensation measures, sum of intermolar angle and mandibular intermolar angle in skeletal Class III malocclusion. 2. There was no statistically significant relationship between the variation in the vertical measures and the variation of posterior dental compensation measures in skeletal Class III malocclusion. 3. There was no statistically significant relationship between the variation in the anteroposterior and vortical measures and degree of basal arch width discrepancy.

Full-mouth rehabilitation in an amelogenesis imperfecta patient with anterior open bite using CAD/CAM system (전치부 개방교합을 보이는 법랑질형성부전증 환자의 CAD/CAM system을 이용한 전악 수복 증례)

  • Lee, Sang-Hoon;Yi, Yang-Jin;Jo, Deuk-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.55 no.4
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    • pp.410-418
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    • 2017
  • Amelogenesis imperfecta characterized as abnormally formed enamel is caused by a defect of unique group of genes. Patients affected by this disease might have difficulties in social and psychological aspects due to non-esthetic teeth as well as functional problems caused by enamel detachment and tooth wear from their early ages. Adult patients with amelogenesis imperfecta can be treated with full-mouth restorations, which make functional and esthetic rehabilitations of severely worn tooth. However, the anterior open bite and lack of occlusal clearance for posterior teeth restorations due to compensatory extrusion are the intervening factors in the prosthetic treatment. Therefore, the determination of anterior tooth lengths, vertical dimension, and anterior guidance should be set carefully. Recently, computer-aided design and computer-aided manufacturing (CAD/CAM) techniques help systematic approaches and enable dentists to reduce time-consuming procedures in the diagnosis and treatment of full-mouth rehabilitation. This case report demonstrates the successful full mouth rehabilitation using a CAD/CAM system in a young adult patient with amelogenesis imperfecta and anterior open bite.

Esthetically improved complete denture by gingival shade alteration: a case report (무치악 환자에서 치은의 색조 개선을 통해 심미성을 향상 시킨 총의치 수복 증례)

  • Yim, Soo-Hyun;Kim, Jee-Hwan
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.3
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    • pp.239-245
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    • 2014
  • Complete denture prosthodontics includes replacement of natural teeth and associated maxillary and mandibular structures for full edentulous patients. The final objectives of prosthodontic treatment include esthetic and functional rehabilitation. Because the esthetic demand of senior patients has increased esthetic requirement should not be overlooked in denture treatment. In complete denture treatment, attempts have been made to reproduce tooth wear, arrangement, recession of cervical gingiva, staining, improved gingival shade and so on. This 61 year old female patient came to the Department of Prosthodontics with the chief complaint that dentures made 5 years ago in a local clinic were broken and did not fit well. The patient put more emphasis on fabrication of natural and esthetic dentures than recovery of masticatory function. Remake of maxillary complete denture and mandibular implant retained overdenture was planned. In order to create esthetic and natural contour, Aesthetic Color Set Easy system$^{(R)}$ (Candulor dental GmbH, Wangen, Germany) was used to make complete dentures reproducing various gingival shades. Patient's esthetic satisfaction was high. When complete denture prosthodontics treatment involves appropriate expression of individual characteristics in addition to proper selection of esthetic materials, treatment will give satisfaction to both dentist and patient.