• 대한치과보철학회지
• /
• 제59권4호
• /
• pp.469-477
• /
• 2021

상악 전치부 임플란트의 성공적인 수복을 위해서는 pink esthetics와 white esthetics가 모두 충족되어야 한다. Pink esthetics 부분의 경우 적절한 임시보철물의 역할이 중요하고, white esthetics 부분의 경우에는 최종 보철물의 색상과 형태가 중요하다. 다층 지르코니아는 기존의 단일구조 지르코니아에 비해 절단 부위의 투명도가 높기 때문에 추가적인 도재 축성 없이 자연스러운 보철물 제작이 가능하다. 따라서 본 증례에서는 상악 전치를 상실한 환자에서 적절한 임시보철물을 통해 기능과 심미성을 충분히 회복한 후 다층 지르코니아를 통해 white esthetics를 달성하였다.

• 대한치과보철학회지
• /
• 제60권3호
• /
• pp.293-300
• /
• 2022

최근 현대인들의 심미적인 치과 치료에 대한 관심이 증가하고 있고, 이와 관련된 다양한 재료와 수복물이 소개되고 있다. 특히 지르코니아는 우수한 강도와 내마모성을 지니며 생체친화성이 있다. 이러한 장점에도 불구하고, 지르코니아의 불투명한 백색으로 인해 전치부 수복치료시 심미적인 한계점이 있다. 최근 색조를 부여한 지르코니아 블록과 투명성이 높은 지르코니아 블록 및 다층 지르코니아 블록 등 다양한 지르코니아 블록이 개발되면서 단일 구조 지르코니아의 활용 범위가 확대되고 있다. 본 증례는 상악 전치부 보철물을 제작을 위해 단색의 Monolithic Zirconia를 이용하여 소결 전에 착색 용액을 도포하여 최종 수복물의 색조를 자연스럽게 재현하였다. 심미 보철 수복 치료시 착색용액을 이용한 지르코니아 사용을 통해 환자와 술자 모두 만족하는 심미적 보철물을 제작하였기에 이를 보고하는 바이다.

• 대한치과기공학회지
• /
• 제41권3호
• /
• pp.195-201
• /
• 2019

Purpose: This study was investigated the effect of multilayer zirconia block type and sintering method on fracture strength, micro structure and color of zirconia copings. Methods: Three kinds of multi-layered zirconia blocks were used to identify the effects of the kinds of multi-layered zirconia blocks and sintering methods on fracture strength and color reproducibility of zirconia copings. 60 Zirconia copings were fabricated and fracture strength, micro structure and color reproducibility were compared and evaluated. Results: In all the blocks, the CS group, which refers to the general sintering method had higher fracture strength of zirconia copings than the MS group that refers to the microwave sintering method(MCS/MMS; 2,107.5N/1,930.4N, DCS/DMS; 917.0N/879.1N, UCS/UMS; 2,256.9/2,050.7N). In relation to CIE $L^*$, $a^*$, $b^*$ values of zirconia copings depending on the kinds of multi-layered zirconia blocks and sintering methods, the MS group using the microwave sintering method had lower brightness and chroma than the CS group using the general sintering method. Conclusion: In all the blocks, the CS group(general sintering) had higher fracture strength of zirconia copings than the MS group(microwave sintering). In relation to CIE $L^*$, $a^*$, $b^*$ values of zirconia copings depending on the kinds of multilayered zirconia blocks and sintering methods, the MS group using the microwave sintering method had lower brightness and chroma than the CS group using the general sintering method.

• 대한치과기공학회지
• /
• 제41권3호
• /
• pp.167-175
• /
• 2019

Purpose: This study was investigated the effect of multi-layer zirconia block type and design location on the mechanical properties of zirconia copings. Methods: Three kinds of multi-layered zirconia blocks (Snow princess multi layered block, Multi cherry, Dental zirconia pre-shaded blank) were used to identify the effects of the kinds of multi-layered zirconia blocks, design locations on mechanical characteristics of zirconia copings. 150 Zirconia copings were fabricated and fracture strength, hardness and microstructure were compared and evaluated. Results: Dental zirconia pre-shaded blank(2,256.9N) had the highest fracture strength of zirconia copings on all the design locations, and it was followed by Snow princess multi layered block(2,107.5N) and Multi cherry(917.0N). Snow princess multi layered block(1,949.7Hv) had the highest hardness of zirconia copings on all the design locations, and it was followed by Dental zirconia pre-shaded blank(1,671.7Hv) and Multi cherry(1,383.7Hv). The cervical layer had the highest fracture strength and hardness of zirconia copings in all the blocks, and it was followed by the cervical+gradation layer, the enamel layer, the enamel+gradation layer, and the gradation layer. Conclusion: It was found that the fracture strength and hardness were different according to the kinds of multilayer zirconia block and design location, and it was confirmed that it is lower than the fracture strength of white zirconia.

• 대한치과기공학회지
• /
• 제44권1호
• /
• pp.1-7
• /
• 2022

Purpose: The purpose of this in vitro study is to evaluate the clinical acceptability of the marginal discrepancies and internal spacing of multi-layered zirconia prothesis by speed sintering. Methods: The two specimen types come from the same manufacturer but differ in the ingredients in layered zirconia and indication, that is anterior and posterior. The designs of both specimens were full contour crowns, and a total of 20 pieces were repeatedly fabricated, 10 for each group. The specimens were divided into two subgroups (n=10) and sintered with various total times (4 hours, 8 hours) at the maximum temperature (1,530℃). The gap between the two groups of multi-layered zirconia prostheses was measured using a silicone replica technique of 2D analysis method. The independent sample t-test was then used to compare and analyze the data obtained from the two groups (α=0.05). Results: The marginal and internal gap was superior in the 8-hour compared to the 4-hour group, and the results exhibited significant differences (p<0.05). All specimens showed that using the speed sintering schedule does not exceed the clinically permitted value of 120 ㎛, meaning zirconia prothesis using the speed sintering was adequate. Conclusion: The sintering condition is shown to affect the marginal and internal gaps of multi-layered zirconia restoration.