Fracture resistance of zirconia and resin nano ceramic implant abutments according to thickness after thermocycling

국문 초록 (Abstract)

목적: 이 연구의 목적은 심미적인 임플란트 지대주의 종류와 두께에 따른 파절 강도를 측정하여 구강 내 저작압에 견디는 최소한의 두께를 평가하기 위함이다. 재료 및 방법: 대조군으로 0.5 mm 두께의 티타늄 임플란트 지대주를(Ti-0.5), 실험군으로 지르코니아 임플란트와 레진 나노 세라믹 지대주를 사용하여 각각 0.5 mm, 0.8 mm, 1.0 mm 두께로 각 그룹에 10개씩 총 70개의 시편을 제작하였다(그룹Zir-0.5, Zir-0.8, Zir-1.0, RNC-0.5, RNC-0.8, RNC-1.0). 모든 시편은 파절 실험 이전에 열순환을 시행하여 구강 내에서의 사용을 재현한 후, universal testing machine을 이용하여 각 시편의 파절 강도를 측정하여 평균값을 측정하였다. 그룹들의 평균 파절 값을 측정하였으며 이원분산분석을 이용하여 통계학적으로 분석하였다. 결과: Zir-1.0군이 가장 높은 파절 강도 $2,476.3{\pm}342.0N$를 보였으며 뒤를 이어 Zir-0.8 ($1,518{\pm}347.9N$), Ti-0.5 ($1,041.8{\pm}237.2N$), Zir-0.5 ($631.4{\pm}149.0N$), 의 순이었다. RNC 그룹의 경우에 Ti와 Zir 그룹에 비교하여 유의하게 낮은 파절 강도값을 나타내었으며(RNC-1.0 $427.5{\pm}72.1$, RNC-0.8 $297.9{\pm}41.2$), 모든 실험군에서 지대주 두께가 감소할수록 파절 강도 값도 유의하게 감소했다(P < .01). RNC-0.5 ($127.4{\pm}35.3N$) 그룹은 다른 모든 군에 비해 유의하게 낮은 값을 보였다(P < .05). 결론: 이번 실험에서 사용된 모든 두께의 지르코니아 지대주는 전치부와 구치부의 교합압을 견딜 수 있는 정도의 파절 강도를 보여주었다. 레진 나노 세라믹 지대주의 경우 0.8 mm 두께 이상에서 전치부의 교합압을 견딜 수 있는 가능성을 보여주었다.

다국어 초록 (Multilingual Abstract)

Purpose: The aim of this in vitro study is to investigate load bearing capacity of esthetic abutments according to the type of material and wall thickness. Materials and methods: 70 specimens equally divided into seven groups according to their abutment wall thicknesses. The abutments prepared with titanium 0.5 mm wall thickness were used as a control group (Ti-0.5), whereas zirconia abutments and resin nano ceramic abutments with wall thickness 0.5 mm, 0.8 mm and 1.0 mm were prepared as test groups (Zir-0.5, Zir-0.8, Zir-1.0 and RNC-0.5, RNC-0.8, RNC-1.0). All specimens were tested in a universal testing machine to evaluate their resistance to fracture and all of them underwent thermo-cycling before loading test. Mean fracture values of the groups were measured and statistical analyses were made using two-way ANOVA. Results: Zir-1.0 showed the highest mean strength ($2,476.3{\pm}342.0N$) and Zir-0.8 ($1,518{\pm}347.9N$), Ti-0.5 ($1,041.8{\pm}237.2N$), Zir-0.5 ($631.4{\pm}149.0N$) were followed. The strengths of RNC groups were significantly lower compared to other two materials (RNC-1.0 $427.5{\pm}72.1$, RNC-0.8 $297.9{\pm}41.2$) and the strengths of all the test groups decreased as the thickness decreases (P < .01). RNC-0.5 ($127.4{\pm}35.3N$) abutments were weaker than all other groups (P < .05). Conclusion: All tested zirconia abutments have the potential to withstand the physiologic occlusal forces in anterior and posterior regions. In resin nano ceramic abutments, wall thickness more than 0.8 mm showed the possibility of withstanding the occlusal forces in anterior region.

참고문헌 (Reference)

1 Gehrke P, "Zirconium implant abutments: fracture strength and influence of cyclic loading on retaining-screw loosening" 37 : 19-26, 2006

2 Gale MS, "Thermal cycling procedures for laboratory testing of dental restorations" 27 : 89-99, 1999

3 Butz F, "Survival rate, fracture strength and failure mode of ceramic implant abutments after chewing simulation" 32 : 838-843, 2005

4 Zembic A, "Randomized-controlled clinical trial of customized zirconia and titanium implant abutments for single-tooth implants in canine and posterior regions:3-year results" 20 : 802-808, 2009

5 Christel P, "Mechanical properties and short-term in-vivo evaluation of yttrium-oxidepartially-stabilized zirconia" 23 : 45-61, 1989

6 Waltimo A, "Maximal contraction force and endurance of human jaw-closing muscles in isometric clenching" 101 : 416-421, 1993

7 Hjerppe J, "Loadbearing capacity of custom-made versus prefabricated commercially available zirconia abutments" 26 : 132-138, 2011

8 Koller M, "Lava ultimate resin nano ceramic for CAD/ CAM: customization case study" 15 : 159-164, 2012

9 Att W, "Influence of preparation and wall thickness on the resistance to fracture of zirconia implant abutments" 14 : e196-e203, 2012

10 Yildirim M, "In vivo fracture resistance of implant-supported all-ceramic restorations" 90 : 325-331, 2003

11 Sailer I, "In vitro study of the influence of the type of connection on the fracture load of zirconia abutments with internal and external implant-abutment connections" 24 : 850-858, 2009

12 Strub JR, "Fracture strength and failure mode of five different single-tooth implant-abutment combinations" 16 : 167-171, 2003

13 Adatia ND, "Fracture resistance of yttria-stabilized zirconia dental implant abutments" 18 : 17-22, 2009

14 Lüthy H, "Flexion resistance of a layered integral ceramic system and two reinvested integral ceramic systems" 47 : 497-501, 1990

15 Zembic A, "Fiveyear results of a randomized controlled clinical trial comparing zirconia and titanium abutments supporting single-implant crowns in canine and posterior regions" 24 : 384-390, 2013

16 Glauser R, "Experimental zirconia abutments for implant-supported single-tooth restorations in esthetically demanding regions: 4-year results of a prospective clinical study" 17 : 285-290, 2004

17 Henriksson K, "Evaluation of custom-made procera ceramic abutments for single-implant tooth replacement: a prospective 1-year follow-up study" 16 : 626-630, 2003

18 Dixon DL, "Comparison of screw loosening, rotation, and deflection among three implant designs" 74 : 270-278, 1995

19 Yildirim M, "Ceramic abutments-a new era in achieving optimal esthetics in implant dentistry" 20 : 81-91, 2000

20 Luthardt RG, "CAD/CAM-machining effects on Y-TZP zirconia" 20 : 655-662, 2004

21 Helkimo E, "Bite force and state of dentition" 35 : 297-303, 1977

22 Manicone PF, "An overview of zirconia ceramics: basic properties and clinical applications" 35 : 819-826, 2007

23 Waltimo A, "A novel bite force recorder and maximal isometric bite force values for healthy young adults" 101 : 171-175, 1993