ISSN eissn Original Article Chemical compatibility of interim material and bonding ag

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1 ISSN eissn Original Article Chemical compatibility of interim material and bonding agent on shear bond strength Jonghyuk Lee* Department of Prosthodontics, College of Dentistry, Dankook University, Cheonan, Republic of Korea Purpose: The purpose of this study is finding proper bonding agents to be used when adding bis-acryl composite provisional materials. Materials and Methods: Three bonding agents with different chemical compositions were included in this study. Forty disk shaped specimens of bis-acryl composite provisional material were prepared and divided into 4 groups according to the bonding agents. Control group didn t have bonding agent. Through the Teflon mould with 4.0 mm diameter hole with 4.0 mm thickness the same bis-acryl composite provisional material was added on the disks after the surface of each specimen was treated with designated bonding agent according to the manufacturer s instructions. Shear bond test was performed and the fractured surfaces were inspected with a microscope. One-way analysis of variance was conducted and the result was further analysed with Turkey post hoc test at the significance level of Results: The highest strength was acquired from the specimens bonded with chemical cure system and it was statistically significant (P < 0.05). This group showed 100% cohesive failures. The lowest bonding strength was recorded from the specimens used conventional light cure bonding agent, and this group s result was similar with the control group. The group used a light cure bonding agent claiming improved compatibility revealed significantly higher bond strength to the traditional light cure bonding agent group in a statistically significant way (P = 0.043). Conclusion: According to the bonding agent used the shear bond strength was significantly affected. Therefore the choice of proper bonding agent is important when hiring a bonding agent to add bis-acryl composite provisional materials. (J Dent Rehabil Appl Sci 2016;32(4): ) Key words: bis-acryl composite provisional material; provisional restoration; shear bond strength; bonding agent 서론 임시수복물은보철치료과정에서치아를보호해줄뿐아니라저작기능및심미성을회복시켜주어환자가치료기간동안느끼는불편을최소로해주어야한다. 1-3 또한파절된부분의수리나변연의적합성향상, 교합의양상이나심미성개선을위해치아의형태를변경이필요한경우쉽게첨가나삭제과정을통해형태의변경이가능해야한다. 2-8 비스아크릴임시수복재료는중합반응시수축과발열이작고높은강도와변연적합도를가져 최근임시수복물재료로그활용이늘고있다. 3,6-11 그러나이러한장점에도불구하고비스아크릴임시수복재료는같은재료의추가에의한수정시약한수리강도를가지기때문에 3,4,12 사용하던보철물이파절되거나형태를많이변경해야하는경우는재제작이권유되기도하였다. 12,13 비스아크릴임시수복재료로만들어진임시보철물에작은결함이있거나수정이필요한경우는 flowable 레진을이용하여수정이가능하며 6,8 수리강도에있어서도유용한결과를보였다. 7,14,15 그러나 flowable 레진을이용 *Correspondence to: Jonghyuk Lee Associate Professor, Department of Prosthodontics, College of Dentistry, Dankook University, 119, Dandae-ro, Dongnam-gu, Cheonan, 31116, Republic of Korea Tel: , hyuk928@dankook.ac.kr Received: November 28, 2016/Last Revision: December 13, 2016/Accepted: December 19, 2016 Copyright 2016 The Korean Academy of Stomatognathic Function and Occlusion. cc It is identical to Creative Commons Non-Commercial License. 293

2 Lee J 한방법은그적용에한계가있고대부분의비스아크릴임시수복재료를사용한임시보철물이직접법으로만들어지는이면에는재료의첨가나수리가어렵다는단점이큰이유로작용한다. 복합레진의수리에서재료간의결합을향상시키기위해다양한표면처리가사용되는데, 표면의거칠기를증가시키고화학적인결합을증가시키기위해연마처리, 입자분사마모, 산부식방법들이비교되었고특수한프라이머나 silane 처리등의화학적성분을본딩제와함께도포해보기도하였다 최근본딩제의경항은시술의단계를간소화하고좀더많은재료에호환성을가지기위해다양한재료를첨가하고 selfetching이가능하도록진화하고있다. 19,20,22,23 그러나재료의중합방식은접촉하는물질의화학적성분에영향을받을수있고, 15,19,20,23 특히계면에서의중합정도는재료들의결합에심각한영향을미친다. 16,19,22-24 그러므로복합레진의수리에사용된방법을임시수복물수리에바로적용하는데는주의가필요하다. 실제로선행연구에서비스아크릴임시수복재료를수리하는데본딩제를사용했을때수리강도의증가에유용한효과를얻지못한경우도있었다. 7,14,15 본딩제의선택에있어서함께사용될재료의중합방식에대한고려가중요한데, 19,23 임시수복물수리에관한연구에서다양한본딩제의효과에관한연구는많지않았다. 본연구에서는중합방식과화학적조성이다른본딩제 들이자가중합형비스아크릴임시수복재료의결합에미치는영향을알아보고자하였다. 귀무가설은본딩재의화학적특성이자가중합형비스아크릴임시수복재료의수리강도에영향을미치지않는다로정하였으며전단결합강도와파절양상을분석하여수리강도에미치는영향을가늠하였고유의수준은 0.05로정하였다. 연구재료및방법 임시수복물을제작하는과정에재료의추가가필요한경우를가정하여연구방법을설계하였으며실험군들을 Table 1과같이설정하였다. 사용된재료들에관한정보는 Table 2에정리하였다. 시편제작을위해 10 mm 5 mm ( 직경 높이 ) 의실리콘몰드를준비하였고비스아크릴임시수복재료 (Luxatemp, DMG, Englewood, USA) 를주입하여 10분간중합이완료되도록기다린후제거하였다. 총 40개의시편이제작되었으며군별로각 10개의시편을사용하였다. 시편을직경 30 mm의원통형테플론몰드바닥중앙에위치시키고자가중합레진 (Ortho-Jet, Lang Dental Manufacturing Co., Wheeling, USA) 을사용하여포매하였다. 포매된시편의표면을다듬고균일한거칠기를부여하기위해 #220-grit 의사포로연마하였고, 에틸알코올과증류수로세척하고건조하였다. 준비된시편은상온의공기중에보관하였다. Table 1. Experiment design Group code Description N CO Luxatemp + Luxatemp, no bonding material, control group n = 10 CF Luxatemp + ClEARFIL (chemical cure bonding agent) + Luxatemp n = 10 SB Luxatemp + Single bond 2 (light cure bonding agent) + Luxatemp n = 10 OS Luxatemp + ONE-STEP (light cure bonding agent ) + Luxatemp n = 10 CO, control; CF, CLEARFIL; SB, Single bond 2; OS, ONE-STEP. Table 2. Materials used in this study Product Manufacturer Composition Batch Luxatemp DMG, Hamburg, Germany Bis-acryl composite resin Ortho-Jet Lang dental, Wheeling, USA Acrylic resin AI/01AD CLEARFIL NEW BOND Kuraray Medical Inc., Osaka, Japan Chemical-cure bonding agent Adper Single bond 2 3M ESPE, St. Paul, USA Light-cure bonding agent N ONE-STEP PLUS Bisco, Schaumburg, USA Light-cure bonding agent Elipar FreeLight 2 3M ESPE, St. Paul, USA LED Curing light 294 J Dent Rehabil Appl Sci 2016;32(4):

3 Chemical compatibility of interim material and bonding agent on shear bond strength 각군별로시편표면에다음과같이본딩제를각각의제조사지시대로처리하였다. 자가중합개시제를별도로제공하는이중중합방식의본딩제 (CLEARFIL TM NEW BOND, Kuraray Noritake Dental, Tokyo, Japan) 는 Bonding agent universal liquid와 Catalyst liquid를 1 : 1 비율로혼합하고마이크로브러시로도포후 1분간약한압축공기로건조하였다 (Group CF). 광중합형본딩제 (Adper TM Single bond 2, 3M ESPE, St. Paul, USA) 는 15 초간동안 2회마이크로브러시로도포하고 5초간약한압축공기로건조한후 10초동안광중합하였다 (Group SB). 광중합형본딩제이지만별도의중합개시제없이자가중합레진과의결합을특성으로하는본딩제 (ONE- STEP PLUS, Bisco Inc., Schaumberg, USA) 는제조사의권장대로본딩제를충분히흔든후사용하였으며 2회도포후 10초간약한압축공기로건조하였고 10초간광중합하였다 (Group OS). 광중합은 Elipar TM FreeLight 2 LED Curing Light (3M ESPE) 를 1,200 mw/cm 2 으로적용하여시행하였다. 대조군으로는본딩제를처리하지않은시편을사용하였다 (Group CO). 본딩제도포후직경 4 mm의원형구멍을가진 4 mm 두께의테플론몰드 (20 20 mm; 가로 세로 ) 를시편에고정시키고비스아크릴임시수복재료를구멍에직접주입하였다. 중합이되도록 5분간기다린후몰드를제거하여시편을완성하였다 (Fig. 1). 완성된시편은상온의공기중에 24시간보관한후만 능시험기 (Instron 3344, Instron Co., Norwood, USA) 를사용하여분당 0.5 mm의 crosshead speed로파절이발생하는시점까지압력을가하여전단결합강도를측정하였다 (Fig. 2). 전단결합강도는파절시최대값 (N) 을시편의표면적으로나누어 megapascal (MPa) 로구하였다. 전단결합강도실험은 ISO/TS (Dental Materials- Testing of adhesive to tooth structure) 에따랐으며, Fig. 2와같이계면에힘을가하였다. 파절된시편은입체현미경 (stereomicroscope, SZ601, Olympus, Tokyo, Japan) 을이용하여 10배율로관찰하였고비스아크릴임시수복재료내부에서파절이발생한경우를응집파절 (cohesive failure), 본딩의계면에서발생한경우는접착파절 (adhesive failure), 두가지재료를모두포함한경우를혼합파절 (mixed failure) 로분류하였다. 평균전단결합강도값을계산한후통계분석프로그램 (PASW for Windows, Ver. 18.0, SPSS Inc., Chicago, USA) 으로일원배치분산분석과 Tukey 사후분석을사용하여유의수준 0.05로검증하였다. 결과 각실험군의평균전단강도값과파절양상을 Table 3 에정리하였다. 얻어진전단결합강도를통계적으로분석한결과각군간에유의한차이가있었고 (Table 4) 사 Fig. 1. Specimen before shear bond strength test. Bisacryl provisional material specimen was embedded in clear acrylic resin to be hold by special jig. Fig. 2. Schematic drawing of shear bond strength test. Load was applied at bonding interface. J Dent Rehabil Appl Sci 2016;32(4):

$Mean and standard deviation (SD) of shear bond strength (unit: Mpa) and failure mode analysis of all specimens (unit: %) Groups Mean ± SD Cohesive fracture Mixed fracture Adhesive fracture CO 12.$

4 Lee J Table 3. Mean and standard deviation (SD) of shear bond strength (unit: Mpa) and failure mode analysis of all specimens (unit: %) Groups Mean ± SD Cohesive fracture Mixed fracture Adhesive fracture CO ± CF ± SB ± OS ± CO, control; CF, CLEARFIL; SB, Single bond 2; OS, ONE-STEP. Table 4. Result of One-way ANOVA test on shear bond strength Sum of squares df Mean square F Sig. Intergroup <.001 Intragroup Sum df, degree of freedom; Sig., significance. Shear bond strength CO Group CF SB * 1 OS } * Mpa Fig. 3. Shear bond strengths of groups are compared and statistically analysed. According to the Turkey post hoc test results, *1 denotes significantly different from the others at the significance level of *2 denotes significant difference between groups at the significance level of CO, control; CF, CLEARFIL; SB, Single bond 2; OS, ONE-STEP. 후검정결과를그래프에통계적유의성으로표시하였다 (Fig. 3). 가장높은전단결합강도는화학중합형본딩제를사용한군 (Group CF) 에서나타났으며 (27.36 ± 4.30 MPa) 모든시편에서비스아크릴임시수복재료에서파절이일어나는응집파절을보였다 (100%). 이는아무런본딩처리를하지않은대조군 (Group CO, ± 3.30 MPa) 에비해두배이상높은값을보인것으로다른실험군들과도통계적으로유의한차이를보였다 (P < 0.05). 실험군중가장낮은값은광중합형본딩제를사용한군 (Group SB) 에서기록되었으며 (13.29 ± 2.56 MPa) 이는대조군과거의유사한값을보였다. 파절양상은 Group CF를제외하고대부분혼합파절을보였다. 동일한광중합방식이지만자가중합레진과의호환성을높였다는본딩제를사용한경우 (Group OS) 전단결합강도에서우수한값을보였으며 Group SB와 Group OS간에통계적으로유의한차이로나타났다 (P = 0.043). 296 J Dent Rehabil Appl Sci 2016;32(4):

5 Chemical compatibility of interim material and bonding agent on shear bond strength 고찰 비스아크릴레진이주성분인임시수복물재료의수리나첨가에있어서본딩제의화학적성질이미치는영향을평가하기위해 3종의각기다른특성을가지는본딩제를도포하여제작한시편과도포하지않은시편의수리전단결합강도를비교하였다. 임시수복물은치아를보호하기위해좋은변연적합을가져야하며이는재이장과정을통해향상될수있다. 5 비록비스아크릴임시수복재료가다른임시수복재료에비해우수한변연적합을보이기는하지만이는재이장과정을하지않은상태에서의비교가대부분의연구결과이었다. 4,9,10 Polymethyl methacrylate (PMMA) 재료의경우높은중합수축으로변연적합의불량이발생하고또중합시발생하는열로인한치수자극을피하기위해구강내에서직접적으로제작할때완전히중합이일어나기전에제거해야하기때문에이로인해변연적합에문제가발생한다. 3,11 그러나 PMMA는첨가되는재료와본재료간의우수한결합으로수리와재이장이가능하여이러한단점을극복할수있으며 3,5,7,13 간접법으로제작후구강내에서재이장하고필요한부위를자유로이삭제, 첨가하는술식상의편의성을가지고있다. 3 이런점에서비스아크릴임시수복재료는사용상의편의성이나교합, 물리적특성의우수함 3,4,10 에도불구하고그사용에한계를가질수밖에없으며수리나첨가에있어신뢰할수있는방법을찾아내는것은중요한문제라고할수있다. 복합레진의수리에관한연구들에서기존재료표면의화학적성질이결합에미치는영향은시간이경과하면서점차감소하며 24 일정기간사용한레진의수리에있어서레진표면의물리적처리가수리결합강도에더중요한영향을미친다. 17,26 그러나표면처리후사용하는본딩제의화학적특성에따라새로첨가되는재료의중합반응과결합력에영향이있을수있음이알려져있다. 16,17,19,20,23,24 비스아크릴임시수복물의수리에관한연구에있어서도다양한표면처리와본딩제의사용효과에대한비교가있었다. 7,13,14,15 Lee와 Lee 15 는연구에서본딩제의사용방법에따라결합강도에영향이있을수있음을보고하였고, Dall Oca 등 24 과 Tay 등의연구에의하면중합이된본딩제이더라도산소와접촉된표면의미중합층의화학적성분이새로첨가되는레진의중합과결합력에영향을줄수있음을보였다. 본연구에서는이러한연구에 근거하여서로다른특성을가지는본딩제들을사용하였을때비스아크릴임시수복재료간의결합강도에미치는연구를확인하고자하였으며, 결과에서임시수복재료와같은화학중합방식에서가장높은결합강도를보였고광중합전용으로개발된본딩제에서가장낮은결합강도를보여본딩제의종류가결합강도에영향을주는것을확인할수있었다. 또한 Table 3의파절양상에서보듯이높은결합강도를보인화학중합본딩제군에서는응집파절양상을보여재료간의결합이매우강했음을보여주었다. 최근의본딩제들은시술의간편화와다양한표면에의접착을위하여많은작용기를포함하며 self-etching을위해낮은산도를가지는특징이있다. 22,23 Sanares 등 20 과 Franco 등 23 은낮은산도가화학중합형레진의중합에영향을미칠수있다고하였다. 이는계면의표면에서산과접촉한중합개시제가변성되어결합면에서중합정도가떨어지는층을형성하기때문이라고하였다. 19,20,23 새로개발된본딩제의경우이러한문제점들을어느정도극복하여함께사용되는레진의종류에무관하게재료의중합에영향을주지않음을강조하고있으며, 본실험에서도광중합방식의본딩제이지만화학중합레진의결합에영향을주지않는다고하는제품을포함시켜보았다. 실험결과화학중합방식본딩제에비해서는낮은값을보였으나광중합전용본딩제에비해서는유의하게높은전단결합강도를보였다. 따라서비스아크릴임시수복재료를사용하여임시수복물을만들때동일한재료를추가하는수정이필요한경우본딩제의선택을적절하게할경우본딩제를사용하지않는경우보다우수한수리강도를얻을수있을것으로생각되었다. 본연구의한계로는우선본실험에서는임시수복물의수리강도를비교하기위해전단결합강도측정을사용하였으나다양한응력환경하에놓아는임시수복물의수리강도를전단결합강도만으로비교하기에는한계가있고좀더다양한파절시험이함께진행되는것이필요하다는것을지적할수있겠다. 또한비스아크릴레진을주성분으로하는다양한임시수복재료와좀더다양한본딩제들이포함되지못하였음을지적할수있겠다. 따라서앞으로이러한다양한재료를포함한연구를통해재료별로가장적절한본딩제조합을찾아내는것이필요할것으로사료된다. 또한본딩제로처리된결합표면의화학적상태에대한좀더정밀한연구가필요할것으로생각된다. J Dent Rehabil Appl Sci 2016;32(4):

6 Lee J 결론 비스아크릴임시수복재료의수리시본딩제의화학적 특성이수리된시편의수리강도에미치는영향을확인하 고자실험을시행하였고다음과같은결론을얻었다. 1. 본딩제의종류에따라비스아크릴임시수복재료의 전단결합강도는영향을받았다. 2. 사용된본딩제중화학중합형본딩제의사용시가장 높은전단결합강도를보였으며이는통계적으로 유의한차이를보였다. 3. 광중합형본딩의경우에서도제품에따라유의하게 차이나는결합강도를보였다. 4. 이상의결과를토대로비스아크릴임시수복재료에 본딩제를사용할경우사용하는재료와의호환성에 대한신중한고려가필요함을알수있었다. Acknowledgements 이연구는 2015 년도단국대학교대학연구비의지원으 로연구되었음 ( 과제번호 : R ). ORCID Jonghyuk Lee References 1. Federick DR. The provisional fixed partial denture. J Prosthet Dent 1975;34: Vahidi F. The provisional restoration. Dent Clin North Am 1987;31: Burns DR, Beck DA, Nelson SK. A review of selected dental literature on contemporary provisional fixed prosthodontic treatment: report of the Committee on Research in Fixed Prosthodontics of the Academy of Fixed Prosthodontics. J Prosthet Dent 2003;90: Wang RL, Moore BK, Goodacre CJ, Swartz ML, Andres CJ. A comparison of resins for fabricating provisional fixed restorations. Int J Prosthodont 1989;2: Zwetchkenbaum S, Weiner S, Dastane A, Vaidyanathan TK. Effects of relining on long-term marginal stability of provisional crowns. J Prosthet Dent 1995;73: Bohnenkamp DM, Garcia LT. Repair of bis-acryl provisional restorations using flowable composite resin. J Prosthet Dent 2004;92: Chen HL, Lai YL, Chou IC, Hu CJ, Lee SY. Shear bond strength of provisional restoration materials repaired with light-cured resins. Oper Dent 2008; 33: Hammond BD, Cooper JR 3rd, Lazarchik DA. Predictable repair of provisional restorations. J Esthet Restor Dent 2009;21: Tjan AH, Castelnuovo J, Shiotsu G. Marginal fidelity of crowns fabricated from six proprietary provisional materials. J Prosthet Dent 1997;77: Young HM, Smith CT, Morton D. Comparative in vitro evaluation of two provisional restorative materials. J Prosthet Dent 2001;85: Driscoll CF, Woolsey G, Ferguson WM. Comparison of exothermic release during polymerization of four materials used to fabricate interim restorations. J Prosthet Dent 1991;65: Koumjian JH, Nimmo A. Evaluation of fracture resistance of resins used for provisional restorations. J Prosthet Dent 1990;64: Balkenhol M, Meyer M, Michel K, Ferger P, Wöstmann B. Effect of surface condition and storage time on the repairability of temporary crown and fixed partial denture materials. J Dent 2008;36: Hagge MS, Lindemuth JS, Jones AG. Shear bond strength of bis-acryl composite provisional material repaired with flowable composite. J Esthet Restor Dent 2002;14: Lee J, Lee S. Evaluation of add-on methods for bis-acryl composite resin interim restorations. J Prosthet Dent 2015;114: Eliades GC, Caputo AA. The strength of layering technique in visible light-cured composites. J Prosthet Dent 1989;61: Brosh T, Pilo R, Bichacho N, Blutstein R. Effect of combinations of surface treatments and bonding agents on the bond strength of repaired composites. J Prosthet Dent 1997;77: Shahdad SA, Kennedy JG. Bond strength of re- 298 J Dent Rehabil Appl Sci 2016;32(4):

7 Chemical compatibility of interim material and bonding agent on shear bond strength paired anterior composite resins: an in vitro study. J Dent 1998;26: Tay FR, King NM, Suh BI, Pashley DH. Effect of delayed activation of light-cured resin composites on bonding of all-in-one adhesives. J Adhes Dent 2001;3: Sanares AM, Itthagarun A, King NM, Tay FR, Pashley DH. Adverse surface interactions between one-bottle light-cured adhesives and chemicalcured composites. Dent Mater 2001;17: Truffier-Boutry D, Place E, Devaux J, Leloup G. Interfacial layer characterization in dental composite. J Oral Rehabil 2003;30: Suh BI. Oxygen-inhibited layer in adhesion dentistry. J Esthet Restor Dent 2004;16: Franco EB, Lopes LG, D Alpino PH, Pereira JC. Influence of ph of different adhesive systems on the polymerization of a chemically cured composite resin. Braz Dent J 2005;16: Dall Oca S, Papacchini F, Goracci C, Cury AH, Suh BI, Tay FR, Polimeni A, Ferrari M. Effect of oxygen inhibition on composite repair strength over time. J Biomed Mater Res B Appl Biomater 2007; 81: Rinastiti M, Ozcan M, Siswomihardjo W, Busscher HJ. Immediate repair bond strengths of microhybrid, nanohybrid and nanofilled composites after different surface treatments. J Dent 2010;38: Jafarzadeh Kashi TS, Erfan M, Rakhshan V, Aghabaigi N, Tabatabaei FS. An in vitro assessment of the effects of three surface treatments on repair bond strength of aged composites. Oper Dent 2011;36: J Dent Rehabil Appl Sci 2016;32(4):

8 Original Article 임시수복재료와본딩제의화학적호환성이전단결합강도에미치는영향 이종혁 * 단국대학교치과대학치과보철학교실 목적 : 중합방식과화학적조성이다른본딩제들이자가중합형비스아크릴임시수복재료의결합에미치는영향을알아보고자하였다. 연구재료및방법 : 원반형태의비스아크릴임시수복재료시편 40개를준비한후본딩제의중합특성에따라대조군을포함 4개의군으로나누었다. 본딩제도포후직경 4 mm의원형구멍을가진 4 mm 두께의테플론몰드를이용하여동일한비스아크릴임시수복재료을첨상하였다. 전단결합강도시험을시행하였으며파절면을현미경으로관찰하였다. 일원배치분산분석과 Tukey 사후분석을사용하여유의수준 0.05로검증하였다. 결과 : 화학중합형본딩제를사용한군에서통계적으로유의한가장높은전단결합강도를보였으며 (27.36 ± 4.30 MPa, P < 0.05) 모든시편에서비스아크릴임시수복재료내에서파절이일어나는응집성파절양상을보였다 (100%). 실험군중가장낮은값은광중합형본딩제를사용한군에서기록되었으며 (13.29 ± 2.56 MPa) 이는대조군과거의유사한값을보였다. 동일한광중합방식이지만화학중합레진과의호환성을높인본딩제를사용한군에서는광중합형본딩제를사용한군에비해통계적으로유의하게높은값을보였다 (P = 0.043). 결론 : 본딩제의종류가수리된비스아크릴임시수복재료의전단결합강도에영향을주며, 비스아크릴임시수복재료의수리시적절한본딩제선택이중요하다. ( 구강회복응용과학지 2016;32(4): ) 주요어 : 비스아크릴임시수복재료 ; 임시수복물 ; 전단결합강도 ; 본딩제 * 교신저자 : 이종혁 (31116) 충남천안시동남구단대로 119 단국대학교치과대학치과보철학교실 Tel: hyuk928@dankook.ac.kr 접수일 : 2016 년 11 월 28 일 수정일 : 2016 년 12 월 13 일 채택일 : 2016 년 12 월 19 일 300

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