도재 소성 과정에서의 고온이 지르코니아 코어의 변연적합도에 미치는 영향 = Influence of High Temperature of the Porcelain Firing Process on the Marginal Fit of Zirconia Core

국문 초록 (Abstract)

본 연구는 치과에서 사용되는 심미 보철물 중에 하나인지르코니아 기반의 전부도재관 제작 시 지르코니아 코어 위에 상부 도재를 축성하고 소성하는 과정에서 발생되는 고온이 완성된 전부도재관의 변연적합도에 미치는 영향을 분석함으로써 임상적 허용이 가능한지 알아볼 뿐 아니라, 치과보철치료를 위한 치과의사, 치과위생사, 치과기공사의 보철물 선택 시 임상적 참고자료로 제공할 목적으로 수행되었다. 심미에 가장 많은 영향을 미치는 상악 중절치를 지대치로 선정하여 동일한 모형 10개 제작 후 각각의 지대치에 적합한 지르코니아 코어를 제작하였다. 제작된 코어의 변연적합도 측정 후 코어 위에 상부 도재를 축성하여 전부도재관을 완성한 뒤 2차 측정을 실시하였으며, 측정 후 비교 분석된 결과는 다음과 같다. 변연적합도는 지르코니아 코어 제작한 후 전부도재관으로 제작되는 과정에 따라 더 커졌으며, 통계적으로도 유의한 차이를 보였다(p＜0.001). 그러나 전부도재관에서 총 80회 측정된 변연적합도의 값에서 임상적 허용 수치인 120 μm을 넘지 않는 결과를 보였으며, 이와 같은 결과를 토대로 지르코니아 코어 위에 상부 도재 소성 시 변연적합도가 커지긴 하나 임상적으로 허용이 가능하다는 결론을 도출하였다.

다국어 초록 (Multilingual Abstract)

One factor for successful prognosis of finished dental prosthesis is good marginal fit. The purpose of this study in vitro investigation was to compare the marginal fit of all-ceramic crown before and after porcelain veneering, to evaluate the influence of high temperature of the porcelain firing on the fit. For this experiment, model of abutment tooth of maxillary right central incisor was prepared. Ten working models were produced. Ten zirconia cores were made by dental computer aided design/computer aided manufacturing system. The marginal fit of specimens were examined using silicone replica technique. Silicone replicas were sectioned four times and were measured through a digital microscope (x160). Marginal fit is a distance connected between edge end part of specimen and abutment margin. Each specimens was measured twice, the first measurement was done prior to veneering porcelain firing, while the second measurement was done after the porcelain firing to evaluate this process. Statistical analyses were performed with paired t-test. Mean±SD marginal fit was 60.8±14.2 μm for zirconia core and 86.1±13.3 μm for all-ceramic crown. They were statistically significant differences (p＜0.001). But all specimens showed a marginal fit where the gap widths ranged within the clinical recommendation (120 μm), all-ceramic crown production using the zirconia core was adequate.

참고문헌 (Reference)

1 한만소, "주조에 의한 Core와 CAD-CAM에 의한 Core의 적합도 비교평가" 한국치위생과학회 12 (12): 368-374, 2012

2 김기백, "전악의 디지털 인상 채득 시 치과용 모형재가 디지털 모형 정확성에 미치는 영향" 한국치위생과학회 12 (12): 617-623, 2012

3 김재홍, "고정성 보철물의 적합도 측정 시 사용하는 실리콘 복제본 기술의 정확도 평가" 한국치위생과학회 12 (12): 566-571, 2012

4 Sarver DM, "The importance of incisor positioning in the esthetic smile: the smile arc" 120 : 98-111, 2001

5 McLean JW, "The estimation of cement film thickness by an in vivo technique" 131 : 107-111, 1971

6 Dederich DN, "The effect of repeated firings on the margins of nonprecious ceramometals" 51 : 628-630, 1984

7 Buchanan WT, "The effect of repeated firings and strength on marginal distortion in two ceramometal systems" 45 : 502-506, 1981

8 Tuntiprawon M, "The effect of cement thickness on the fracture strength of all-ceramic crowns" 40 : 17-21, 1995

9 Denry I, "State of the art of zirconia for dental applications" 24 : 299-307, 2008

10 Luthardt RG, "Reliability and properties of ground Y-TZP-zirconia ceramics" 81 : 487-491, 2002

11 Gulker I, "Margins" 51 : 213-217, 1985

12 Hamaguchi H, "Marginal distortion of the porcelain bonded-to-metal complete crown: an SEM study" 47 : 146-153, 1982

13 Moldovan O, "Internal and external fit of CAM-made zirconia bridge frameworks-a pilot study" 61 : 38-42, 2006

14 Komine F, "Influence of porcelain-firing procedures on the marginal distortion of electroformed metal-ceramic restorations" 38 : E583-E588, 2007

15 Faucher RR, "Distortion related to margin design in porcelain-fused-to metal restorations" 43 : 149-155, 1980

16 Bridger DV, "Distortion of ceramometal fixed partial dentures during the firing cycle" 45 : 507-514, 1981

17 Conrad HJ, "Current ceramic materials and systems with clinical recommendations: a systematic review" 98 : 389-404, 2007

18 Rosenstiel SF, "Contemporary fixed prosthodontics" Elsevier, St. Louis 774-, 2006

19 Reich S, "Clinical fit of all-ceramic three-unit fixed partial dentures, generated with three different CAD/CAM systems" 113 : 174-179, 2005

20 Ostlund LE, "Cavity design and mathematics: their effect on gaps at the margins of cast restorations" 10 : 122-137, 1985

21 Vigolo P, "An in vitro evaluation of fit of zirconium-oxide-based ceramic four-unit fixed partial dentures, generated with three different CAD/CAM systems, before and after porcelain firing cycles and after glaze cycles" 17 : 621-626, 2008

22 Sulaiman F, "A comparison of the marginal fit of in-ceram, IPS empress, and procera crowns" 10 : 478-484, 1997