• 대한치과보철학회지
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• 제38권4호
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• pp.544-551
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• 2000

A fabrication method of inner and outer crown using CAD/CAM is presented. The information of abutment teeth is transferred to a computer through a 3-dimensional scanner. A Konus inner and outer crown is designed on a computer and a real crown is machined based on this design using CAM. This method can save laboratory time and reduce inaccuracies compare to conventional casting procedure. A stone model with six prepared abutment teeth from a patient was used in this study. Three dimensional information from the model was transferred to a computer using a contact type 3-dimensional scanner with a $25{\mu}m$ accuracy. All margins were identified on a computer image where there is a change in surface taper of a model. To provide a cement space, the image of a inner sur face of a Konus inner crown was duplicated $25{\mu}m$ apart from the surface of a prepared abutment teeth image. The cement space was $20{\mu}m$ at the cervical margin. All Konus crowns were machined with a $10{\mu}m$ accuracy. It was concluded that this method can reduce working-time for the laboratory process and increase accuracy. A further research is required to make a simplified process for a more complex prosthesis.

• 구강회복응용과학지
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• 제40권1호
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• pp.24-30
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• 2024

청소년기 외상으로 인한 상악 전치부의 복잡 치관 파절은 기능적, 심미적 문제를 야기할 수 있다. 치수 노출을 동반한 치관 파절은 남아있는 치질의 양에 따라 다양한 수복 방법을 고려할 수 있다. 직접 레진 수복은 가장 일차적으로 고려되는 전통적이고 효과적인 방법이나 시간이 지남에 따라 변색되고 깨질 가능성이 높다. 전장관 수복은 성장기의 치아 이동으로 변연 부조화에 의한 재수복 가능성이 높으며 광범위한 치관 파절 시 주로 시행하는 포스트 수복은 치근 천공 및 치근 파절의 위험성을 증가시킨다. 그러나 Endocrown은 치수강 공간으로부터 유지력을 얻을 수 있는 일체형 구조로 생체역학적 측면에서 효과적인 재건이 가능하고 기능과 심미성의 회복에 유리한 이점을 제공한다. 따라서 Endocrown은 청소년기 외상으로 인한 복잡 치관 파절의 수복 방법으로 고려할 수 있다.

• 대한소아치과학회지
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• 제49권1호
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• pp.45-56
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• 2022

이 연구의 목적은 심한 우식 또는 저광화에 이환된 제1대구치에 기성금속관을 수복한 후 교합 변화에 대해 평가하는 것이다. 제1대구치가 교합 평면까지 도달하여 교합되는 환자 중 기준에 부합하는 24명의 환자를 대상으로 연구를 진행하였다. 하나의 제1대 구치에 기성금속관으로 수복치료를 진행하였다. 치료 전, 치료 직후, 4주 후, 8주 후 검진마다 T-Scan III을 사용하여 최대교두감합위에서 교합력 분포를 측정하였고 디지털 버니어 캘리퍼로 수직피개를 측정하였으며 정중선의 변화를 조사하였다. 8주 후 검진에서는 설문 조사를 진행하였다. 대부분 치료 전과 비교해서 치료 직후 악궁에서 수복한 쪽과 수복하지 않은 쪽 사이의 교합력 분포가 역전되었으며 수직피개는 감소했다. 하지만 4주 후에 좌, 우측 교합력이 평형을 이루었고 수복한 제1대구치와 수복하지 않은 제1대구치의 교합력 분포는 비슷한 값을 가졌다. 또한 변화한 수직피개, 정중선은 치료 전 상태로 회복되었고 치료 후 유의할만한 턱관절 및 저작 불편감은 없었다. 이번 연구를 통해 기성금속관 수복 후 한 달 뒤에 자발적인 교합 평형이 이루어진 것을 확인할 수 있었다.

• 대한소아치과학회지
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• 제50권3호
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• pp.307-317
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• 2023

심미성에 대한 요구가 증가함에 따라 유구치 수복을 위한 지르코니아 전장관은 더 활발하게 사용되고 있으나, 지르코니아 전장관으로 수복한 치아를 장기간 추적 관찰하거나 다른 재료와 비교한 연구는 많지 않다. 따라서 이 연구의 목적은 인접면 우식증에 대한 지르코니아 전장관과 기성금속관의 36개월 동안의 생존율을 비교하여 평가하고, 각 기성관의 수복 실패 양상을 분석하는 것이다. 2017년부터 2019년까지 조선대학교 치과병원 소아치과와 두 개의 개인 치과의원에 내원하여 두 기성관으로 수복 치료를 받은 498명 환자에 대한 1,061개의 유구치에 대한 전자의무기록지와 방사선 사진을 수집하고 분석하였다. 생존분석 결과, 기성금속관으로 수복한 치아의 생존율이 지르코니아 전장관에 비해 유의하게 높았다. 치수 치료 시행 여부를 나눠 생존 분석을 시행한 결과, 치수 치료를 시행하지 않은 경우, 기성금속관의 생존율이 지르코니아 전장관에 비해 유의하게 높았던 반면, 치수 치료를 시행한 경우에는 두 기성관의 생존율에 유의한 차이가 없었다. 기성금속관의 주된 수복실패 원인은 비정상적 치근 흡수 또는 치근단 투과상 병소의 발생이었고, 지르코니아 전장관의 경우 수복물의 탈락이었다. 이 연구는 임상가들에게 구치부 기성관 재료 선택 시 참고 자료로 활용될 수 있을 것이라 생각된다.

• 대한치과기공학회지
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• 제29권2호
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• pp.49-64
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• 2007

This research collected the curriculum for Dental Technology from a total of 20 schools -3-year colleges and 4-year colleges- all in Korea. And we analyzed the average credits of subjects from students. As a result of this analysis, we get the conclusion below: 1. In a distribution which students answered about each subjects; Seminar, Dental morphology I II, Dental morphology practice I II, and Dental devices & instruments don't have many credits and mostly have a converged tendency in high points, according to the arithmetic mean of the major basis subjects. 2. In an analysis of the correlation which is based on the distinction of sex: Complete denture prosthodontics I II III, Dental orthodontics I II, Dental orthodontics practice I II, and Dental orthodontics & practice III have a meaningful difference. ($\rho$< 0.05 ) 3. In an analysis of the correlation which is based on an age The major basis subjects -Introduction to dental technology, Dental esthetic, and Dental casting procedure-, and the major application subjects -Crown and bridge prosthodontics practice, Complete denture prosthodontics, Dental orthodontics, Dental orthodontics practice, and Operative dentistry laboratory technology- have meaningful difference. ($\rho$< 0.05 ) 4. In a correlation coefficient between subjects; The correlation coefficient of the major application subjects is higher than the major basis subjects. According to the student - t, we found that the level of significance is $\rho$< 0.001, which is meaningful. We feel the lack of a limitation which we didn't survey all students who are major in Department of Dental Technology. And we also feel that we'd better to consider not only students who being in college but also graduated students.

• 대한치과기공학회지
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• 제41권1호
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• pp.31-41
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• 2019

Purpose: This provides basic data for improving educational effectiveness by selecting and applying basic vocational competency applicable to dental technology's sub-major curricula by determining and researching dental technicians' awareness levels concerning the basic vocational competency's importance. Methods: 170 dental technicians working in Daegu, Korea were surveyed using a self-administered questionnaire between 9 January 2018 and 23 February 2018. Results: 1. The highest level of the basic vocational competency elements by the awareness levels of importance in dental technology laboratories was shown in the occupational ethics, followed by technological skills, interpersonal skills, self-development levels, problem-solving skills, information skills, resource management skills and skills for understanding groups, communication skills, and mathematical skills. 2. Female dental technicians put relatively higher importance on writing documents and managing time, while males stressing on basic statistics. 3. Dental laboratory CEOs and managers put high values on resource management skills, while head technicians valuing information skills more. 4. The awareness levels concerning the basic vocational competency importance in some dental technology fields did not match those of the dental technology laboratories in the fields of porcelain, crown and bridge, and orthodontics. Conclusion : This study demonstrates that the awareness levels concerning basic vocational competency's importance in some fields of dental technology differ from those of dental technology laboratories. Developing a basic vocational competency curriculum, it seems necessary to find ways to increase educational effectiveness by selecting and applying the basic vocational competency for the respective fields of dental technology.

• 대한치과기공학회지
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• 제10권1호
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• pp.159-169
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• 1988

Fixed prosthetic appliance is the restorations of damaged teeth with cast metal or porcelain, and of replacing missing teeth with fixed, or cemented prosthesis. Successfully treating a patient by means of fixed prosthodontics requires the thoughtful combination of dentist and dental laboratory technician. In order to know the satisfaction of dentisits about fixed prosthetic appliances-porcelain, precious and non precious metal-, this study was conducted for 69 practicing dentisis in Pusan during Fed. to Mar. 1988 using a questionnaire method and was analyzed by the use of percentage, $X^2$-test The results are obtained as follow: 1. General characteristics of the respondents, The rate of age distribution of practcing dentists responded was as follow : 31$\sim$35 age group is 29.0%, 51$\sim$55age group 18.8%, 41$\sim$45 age group and 46$\sim$50 group each 11.6%, 36$\sim$40 age group and 56$\sim$60 age group 8.7%, over 60 age group 7.3%, below 30 age group 4.3% respectively. The tate of term of practice experience distribution of dentists responded was as follow : 6$\sim$10 year group 26.1%, 25$\sim$25year group 18.8%, 11$\sim$15 years group and 16~20 years group each 13.0%, below 5 years group and over 30 years group each 10.2%, 26$\sim$30 years group 8.7% in order. The rate of respondents’ degree was follow : bachelor group 81.2%, doctor group 13.0%, master group 5.8% in order. The rate of respondents’completed medical specialist course was as follow : non-complete group 75.4%, complete group 24.6%. The rate of having own laboratory in respondents’clinic was as follow : no having own laboratory group 58.0%, having own labiratory group 42.0% The rate of being lab. technician in respondent;s clinic was as follow: non-being lab. technician group 91.3%, being lab. technician group 8.7%. The rate of transactional commercial dental lab. numbers was as follow : I dental lab. group 40.6%, 2 dental lab. group 30.4%, 3 dental lab. group 20.3%, production at own lab. group 8.7% 2. Cognitions about the respondent's job, About cognition of patient numvers, there were neither many nor few group 62.3%, few group 17.4%, many group 15.9%, too many group 4.4% in order.(P<.01) As compared with the ratio of dentists to patient prothetic treatment, there were moderate level group 46.4%, high level group 33.6%, low level group 18.8% in order.(P<.01) By job satisfaction of respondents, the highest percentage group was satisfied group 44.9%, neither astisfied nor disstified group 33.3%, dissatisfied group 14.5%, much satisfied group 7.3%(P<.01). As compared with the level of prosthetics price, the were moderate level group 71.0%, low level group 23.2%, high level group 5.8%(P<.01) 3. Satisfaction and assessment of dissatisfied factor of the fixed prosthetic appliance, As compared with the satisfaction of al prosthetic appliance, there were neither satisfied nor dissatisfied group 59.4%, satisfied group 20.3% dissatisfied group 18.8%, much satisfied group 1.5% in order.(P<.01). About precious and non precious metal crown and bridge, there were neither satisfied nor dissatisfied group 60.9%, satisfied group 24.6%, dissatisfied group 11.6%, much satisfied group 2.9% in order.(P<.01) The reat of respondent;s satisfaction about porcelain crown and bridge was as follow : neither satisfied nor dissatisfied group 43.5%, dissatisfied group 33.3%, satisfied group 21.7%, much satisfied group 1.5%(P<.01). The rate of respondent's dissatisfied factor item of precious and non precious metal crown and bridge was as follow : inadequate margin fit item 39.1% respondent, inadequate occlusion item 24.6%, inadequate adaptation item 23.2%, poor anat omic form item 15.9%, inadequate contact item 31.9%, improper polishing item 4.4%, the rest item 11.6% respectively. The rate of respondent's dissatisfied factor item of porcelain crown and bridge was as follow : inadequate margin fit item 52.2%, inadequate occlusion item 2.9%, inadequate adaptation item 10.1%, poor anatomic form item 11.6%, improper polishing item 1.5%, shade mismatching item 71%, the rest item 7.2% respectively. The rate of cognition of respondents’ about cause of dissatisfied factor on fixed prosthetic appliance by item was as follow : deficiency of sincerity item 55.1%, deficiency of knowledge about work item 47.8%, deficiency of experience item 15.9%, poor quality of using material item 5.8%, the rest item 2.9% respectively.

• 한국치위생학회지
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• 제11권1호
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• pp.127-136
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• 2011

Objectives : The writer aimed to examine the dynamic aspect on damage and to be conducive to the swift cure according to right treatment to educate prevention of injury through surveying on the number of the damaged teeth given injury, tooth kind, type in damage, place and cause for being damaged, frequency by month and by time level, and location of the damaged tooth. Methods : Targeting 343 teeth of receiving injury in 201 patients who visited the department of pediatric dentistry, the department of preservation, and the oral and maxillofacial surgery in a dental hospital in Cheonan city from April 2007 to April 2009, by having the dental injury as the main reason, the following conclusions were obtained. Results : 1. Deciduous teeth were indicated to be the highest in imperfect luxation with 60.7%, and were indicated to be in order of crown fracture with 25.5%, root fracture with 12.4%, and perfect luxation with 1.4%. The permanent teeth were indicated to be the highest in crown with 58.1%, and were indicated to be in order of imperfect luxation with 27.3%, root fracture with 13.1%, and perfect luxation with 1.5%(p<0.001). 2. In case of deciduous teeth for a place with damage, the home was indicated to be the highest with 31.7%. The permanent teeth were indicated to be the highest(p<0.001) in the road and stairs with 40.4%. As to a cause for damage, both deciduous and permanent teeth were indicated to be the highest(p<0.001) in a cause for falling with 53.1% and 30.8%, respectively. 3. As for a treatment method, in case of deciduous teeth, the close observation was indicated to be the highest with 46.9%. In permanent teeth, the resin restoration was indicated to be the highest(p<0.001) with 22.2%. Dental injuries in deciduous teeth and permanent teeth are showing diverse aspects. Conclusions : It is important to arrange guidelines on cure of the damaged teeth by injury through continuing a dynamic research on these aspects. Also, the damage in deciduous teeth may have direct and indirect influence upon growth in successional permanent teeth. Thus, through careful treatment, the injury needs to be minimized. It is considered to be likely necessary for a right coping method when injury occurs, and above all, for enough prior education so that injury cannot occur.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.56-61
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• 2015

PURPOSE. The purpose of this study was to evaluate the effects of the surface treatment and shape of the dental alloy on the composition of the prosthetic work and its metallic ion release in a corrosive medium after casting. MATERIALS AND METHODS. Orion Argos (Pd-Ag) and Orion Vesta (Pd-Cu) were used to cast two crowns and two disks. One of each was polished while the other was not. Two as-received alloys were also studied making a total of 5 specimens per alloy type. The specimens were submersed for 7 days in a lactic acid/sodium chloride solution (ISO standard 10271) and evaluated for surface structure characterization using SEM/EDAX. The solutions were quantitatively analysed for the presence of metal ions using ICP-MS and the results were statistically analysed with one-way ANOVA and a Tukey post-hoc test. RESULTS. Palladium is released from all specimens studied (range $0.06-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$), with the Pd-Cu alloy releasing the highest amounts. For both types of alloys, ion release of both disk and crown pairs were statistically different from the as-received alloy except for the Pd-Ag polished crown (P>.05). For both alloy type, disk-shaped pairs and unpolished specimens released the highest amounts of Pd ions (range $0.34-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). Interestingly, in solutions submerged with cast alloys trace amounts of unexpected elements were measured. CONCLUSION. Shape and surface treatment influence ion release from dental alloys; polishing is a determinant factor. The release rate of cast and polished Pd alloys is between $0.06-0.69{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$, which is close to or exceeding the EU Nickel Directive 94/27/EC compensated for the molecular mass of Pd ($0.4{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). The composition of the alloy does not represent the element release, therefore we recommend manufacturers to report element release after ISO standard corrosion tests beside the original composition.

• 대한장애인치과학회지
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• 제15권1호
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• pp.50-54
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• 2019

본 증례는 다수의 치아우식증을 주소로 내원한 근이영양증 환자의 전신마취 하 치과치료에 대한 보고이다. 근이영양증 환자들은 진행성 근육 약화로 인해 구강위생 관리하기가 힘들고 치아우식이 호발할 수 있다. 따라서 정기적으로 치과를 내원하고 올바른 구강 위생 습관을 확립할 수 있도록 환자 및 보호자교육을 실시하여야 한다. 치과치료 시에는 흡인으로 인한 호흡기 합병증이 발생하지 않도록 액체의 흡입을 주의 깊게 하여야 한다. 비협조적이거나 매우 어린 근이영양증 환자에서는 전신마취가 필요할 수 있다. 전신마취 시에는 악성 고열증의 위험 때문에 휘발성 마취제를 피해야 한다.