수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 었다. 그러나새로운제품들이개발되면서글래스아이오노머시멘트와함께이장재로서사용빈도가증가되고있다. 즉이는수산화칼슘제재가상아질의광화를유도하며 16), 잔존상아질의재광화를촉진하고살균효과때문에노출치수의복조재로도사용이추천되고있다.

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1 대한치과보존학회지 : Vol. 32, No. 3, 2007 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 박노훈 박상혁 최기운 박상진 * 경희대학교대학원치의학과치과보존학교실 ABSTRACT EFFECT OF CALCIUM HYDROXIDE ON BOND STRENGTH OF DENTIN BONDING SYSTEMS No-Hoon Park, Sang-Hyuk Park, Gi-Woon Choi, Sang-Jin Park* Department of Conservative Dentistry, Division of Dentistry, Graduate of Kyung Hee University The purpose of this study was to investigate the effect of calcium hydroxide on dentin bonding strength of various dentin bonding systems as a function of time in composite resin restoration. Dentin adhesives used in this study were Scotchbond Multipurpose, Single Bond, SE Bond and Prompt L-Pop. Flat dentin surfaces adjacent to pulp chamber were created, then Ca(OH)2 and saline were mixed and applied on dentin surface of experimental group, then IRM was used to cover the mixture on dentin surface and the specimens were stored at 36.5 for experiment period (7 days, 30 days). After removing IRM and Ca(OH)2, each dentin adhesives were treated on dentin surfaces. Composite resin (Z-250, 3M) was placed with 5 mm height and was light-cured for 20 seconds. After stored in distilled water for 24 hours, each dentin-composite bonded spicemen was embedded in epoxy resin and sectioned into mm2 cross section composite-dentin beams. Specimen was mounted on zig of Universal testing machine and μtbs test was performed. SEM analysis was performed to examine the fractured surfaces. The results suggested that applying calcium hydroxide did not show significant difference in dentin bonding strength. [J Kor Acad Cons Dent 32(3): , 2007] Key words: Calcium hydroxide, Dentin bonding systems, Composite resin restoration, Dentin bonding strength, μtbs test, SEM analysis - Received , revised , accepted Ⅰ. 서론 수산화칼슘은높은알칼리성으로살균효과가있어근관치료약제로널리사용되고있으며 1,2), 근관치료뿐아니라 * Corresponding Author: Sang-Jin Park Department of Conservative Dentistry, Division of Dentistry, Graduate of Kyung Hee University 1, Hoegi Dong, Dongdaemun Gu, Seoul, Korea, Tel: psangjin@khu.ac.kr 보존수복분야에서도다양한용도로사용되어왔다. 즉간접또는직접치수복조술식에수산화칼슘성분이포함된재료가널리사용되고있으며 8-13), 최근미세누출의우려로사용이감소했지만수산화칼슘제재가깊은와동의치수보호목적의이장재로사용되어왔다 3-7). 한편복합레진이생체적합성을가지고치수에유해하지않다는것이밝혀졌지만 14), 치수와가까운깊은와동의경우, 중합과정에서발생하는열이치수에유해한자극을가할가능성은상존한다 15). 경화형수산화칼슘제제들이 Bis- GMA 계열레진의중합반응을방해하지않지만, 초기의제품들은미세누출의문제로인해이장재로의사용이제한되 198

2 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 었다. 그러나새로운제품들이개발되면서글래스아이오노머시멘트와함께이장재로서사용빈도가증가되고있다. 즉이는수산화칼슘제재가상아질의광화를유도하며 16), 잔존상아질의재광화를촉진하고살균효과때문에노출치수의복조재로도사용이추천되고있다. 수산화칼슘을깊은와동에서이장재로사용하기시작한것은오래전의일로 1950년대중반이후로수많은종류의수산화칼슘제제들이사용되어왔으며치수의생물학적, 구조적보호에가장이상적인재료로여겨져왔다 5). 근래에는다양한종류의이장재들이사용되면서수산화칼슘제재들의비중이다소감소하고있지만, 광중합형제재는다른자가경화형이장재들에비해낮은미세누출을나타내는것으로보고된바있다 6). 수산화칼슘제제는또한치수복조술식에도널리사용되어왔다. 최근다양한치수복조제가사용되고있고, 별도의제재없이상아질접착제만을사용하는방법도제시되고있지만, Scarano A 등 13) 의연구에서자가경화형수산화칼슘제재와광중합형수산화칼슘제재모두양호한생체적합성을가진다는것이밝혀졌으며, Fitzgerald M과 Heys RJ 8) 는두종의상용화된자가경화형수산화칼슘제재가간접또는직접치수복조술식모두에서양호한조직학적, 임상적결과를나타냈다고보고한바있다. 또실활치표백술시에도수산화칼슘제제가사용되고있으며, 이는과산화수소에의한높은산성이염증성치근흡수를야기할수있으므로 17), 이를방지하기위한기재또는표백술이후의와동소독에수산화칼슘이사용되고있다 18,19). 수산화칼슘이이와같이다양한용도로사용되고있지만, 최종수복이필요한과정에서상아질접착제의병용이필요한경우가있다. 이경우수산화칼슘의높은알칼리성은조직변성을일으킬수있으며 20), 상아질접착제의접착효과에영향을미칠가능성이있다. 실제로수산화칼슘을일주 일간적용한경우, 상아질에대한글래스아이오노머시멘트 sealer 의접착강도의감소가보고된바있으며 21), 콜라겐의변성으로인한접착효과의위해성이나타날수도있다. 그러나수산화칼슘제제를단기간사용한경우에는상아질에대한접착강도에영향이없다는보고도있었다 22). 하지만이연구에서는 2 단계 total-etching 과정을지닌 2 종의접착제만을사용하였는데, 현재사용되고있는다양한상아질접착제들은각기다른도말층처리방법과다양한접착과정을가진다. 따라서위실험의결과만으로모든종류의상아질접착제가수산화칼슘제제의단기간사용에의해영향을받지않을것이라고생각할수는없다. 본연구는다양한접착과정과기전을지닌 4 종의상아질접착제를이용하여수산화칼슘의사용여부및그적용기간이접착강도에미치는영향을측정및평가하고주사전자현미경을이용한접착계면의관찰을통해복합레진수복이나레진시멘트를이용한수복물접착시에적절한상아질접착제의선택과사용방법을알아보고자시행되었다. 1. 실험재료 Ⅱ. 실험재료및방법 1) 실험치아우식이없는발거한 36 개제 3 대구치를생리식염수에보관한후실험에사용하였다. 2) 실험재료본실험에사용한상아질접착제는 3 단계접착제인 Scotchbond Multi-Purpose (3M, Dental Products, St. Paul, MN, USA), 2 단계 total-etching 접착제인 Single Bond (3M, Dental Products, St. Paul, MN, USA), 2 단계자가부식형접착제인 Clearfil SE Bond (Kuraray Table 1. Dentine adhesives and composite resin used in this study Adhesives (Lot No.) Main Components Manufacturer Scotchbond Multipurpose Etchant (35% phosphoric acid), Primer (HEMA, 3M (4AP, 5PB) Polyalkenoic acid copolymer), Adhesive (HEMA, Bis-GMA) (St. Paul, USA) Single Bond Etchant (35% phosphoric acid), Adhesive (HEMA, 3M (5CC) Bis-GMA, Polyalkenoic acid copolymer) (St. Paul, USA) Clearfil SE Bond Primer (MDP, HEMA, water), Adhesive (MDP, Kuraray Co. (00524A, 00738A) dimethacrylate, HEMA, microfiller) (Osaka, Japan) Prompt L-Pop Water, stabilizer, parabenes, methacrylated phosphoric 3M (214182) acid esters, fluoride complex, photoinitiator (BAPO) (St. Paul, USA) FiltekTM Z-250 Universal TEG-DMA, UDMA, Bis-EMA, 3M Restorative (5LGJ, 3KWJ) Zirconia / silica filler (St. Paul, USA) 199

3 대한치과보존학회지 : Vol. 32, No. 3, 2007 Table 2. Modes of bonding procedure of four adhesives Adhesives Modes of bonding procedures 1. etch for 15s, wash and blot dry Scotchbond Multipurpose 2. apply primer, gently dry for 5s 3. apply adhesive, light-cure for 10s 1. etch for 15s, wash and blot dry Single Bond 2. apply adhesive(2 coats), gently dry for 5s, light-cure for 10s 1. apply primer for 20s, gently dry Clearfil SE Bond 2. apply adhesive, light-cure for 10s 1. apply adhesive 15s, gently dry, apply adhesive 3s (2 coats), Prompt L-Pop gently dry, light-cure for 10s Table 3. Experimental groups and code by adhesives used in this study Group dwell time Code Adhesives SM/C Scotchbond Multipurpose Control - SB/C Single Bond SE/C Clearfil SE Bond PL/C Prompt L-Pop SM/7 Scotchbond Multipurpose Ca(OH)2 7 days SB/7 Single Bond 7 days SE/7 Clearfil SE Bond PL/7 Prompt L-Pop SM/30 Scotchbond Multipurpose Ca(OH)2 30 days SB/30 Single Bond 30 days SE/30 Clearfil SE Bond PL/30 Prompt L-Pop Co., Osaka, Japan), 1단계자가부식형접착제인 Prompt L-Pop (3M, Dental Products, St. Paul, MN, USA) 등 4종이며, 각각의주요구성성분은 Table 1과같다. 복합레진으로는 Filtek TM Z-250 Universal Restorative(3M, Dental Products, St. Paul, MN, USA) 를사용하였고주요구성성분은 Table 1과같다. 2. 실험방법 1) 실험군분류시편처리방법에따라수산화칼슘을적용하지않은대조군, 수산화칼슘을 7 일간적용한군및수산화칼슘을 30 일간적용한군으로분류하고각군을다시각각 4 종의상아질접착제를사용한경우에따라재분류하고이를조합하여 4 개의대조군과 8 개의실험군등총 12 개의군으로분류하였으며, 이를 Table 3 에요약하였다. 2) 시편제작 A. Tooth Preparation 실험치아를고속핸드피스와다이아몬드버를사용하여주수하에치아장축에수직으로절단하여법랑질을제거하고치수강에근접한상아질표면을노출시킨후, 도말층의표준화를위하여 320-grit silicon carbide abrasive paper 로주수하에연마하였다. B. Caicium hydroxide application Ca(OH)2를생리식염수와혼합하여실험군치아 24개의법랑질변연을제외한상아질표면에약 2 mm두께로적용한후, IRM (Intermediate Restorative Material, 200

4 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 Dentsply Caulk, Milford, USA) 으로적용된수산화칼슘및변연부위의상아질과법랑질모두를밀폐하여 36.5 증류수에서실험기간 (7 일및 30 일 ) 동안보관하였다. C. Bonding and composite build-up IRM 을제거하고 air/water syringe 로 Ca(OH)2 의표면적용부위를세척한후, 대조군및실험군에 4 종의상아질접착제를제조사의지시에따라적용하였으며그방법은 Table 2 와같다. 대조군의치아를실험군의시편형성과동일하게도말층형성및수세후, 대조군과실험군의시편에상기 4 종의접착제를각각도포, 적용하였다. Silicon 으로제작한 custom mold 를처리한상아질표면에위치시킨후복합레진을 3 회에나누어총 5 mm높이로적층하고, 각층마다 20 초씩광조사를시행한뒤 mold 를제거하여미세인장접착강도측정용시편을제작하였다. 3) 미세인장접착강도측정 (measurement of microtensile bond strength) 모든시편을 24 시간동안증류수에보관한후, acrylic ring ( 직경 20 mm, 높이 15 mm ) 내에자가중합 epoxy 레진을부어제작된시편을포매하였다. Low-speed diamond saw (ISOMET, Buehler, Lake Bluff, USA) 를이용하여주수하에교합 - 치은방향으로절단하여 1 mm두께의 slab 으로제작하였고, 다시 Shono 등 23) 이보고한미세인장접착강도측정방법의 Non-trimming 방법을이용하여절단하여 mm2의단면적을가지는복합레진 - 상아질 beam 을형성하였다. Beam 으로제작된시편을 cyanoacrylate adhesive (Zapit, DVA, Lewis Ct. Corona, USA) 를이용하여미세인장접착강도측정용 zig 에부착하였다. Universal testing machine (EZ-Test, Shimadzu, Japan) 을이용하여 1 mm /min 의 crosshead speed 로하중을가하여미세인장접착강도를측정하였다. 4) 주사전자현미경관찰 (SEM examination) 상아질접착제가도포된상아질의파단면을관찰하기위하여건조및금이온증착하여가속전압 20 kvp 에서주사전자현미경 (S-3200, Hitachi Co., Japan) 으로 2,000 배로관찰하였다 (Figure 7-14). 5) 통계분석대조군및실험군의측정된미세인장접착강도를 oneway ANOVA 및 Duncan s multiple comparison test 를이용하여 95% 의신뢰구간에서분석하였다 (Table 4). 1. 미세인장접착강도 Ⅲ. 실험성적 Table 4 와 Figure 2 는 12 개의대조군및실험군의미세인장접착강도를측정한결과이다. 상아질에수산화칼슘을적용하지않은대조군과수산화칼슘을 7 일간적용한실험군에서는 Scotchbond Multi-Purpose (SM) 와 Clearfil SE Bond (SE) 를사용한경우, Single Bond (SB) 와 Prompt L-Pop (PL) 을적용한경우에비하여유의성있게 Table 4. Micro-tensile bond strength of 12 experimental groups ( MPa ± SD) Group Adhesive (Code) Strength Scotchbond Multipurpose (SM/C) 36.6 ± 8.9 a Control Single Bond (SB/C) 22.6 ± 7.6 b Clearfil SE Bond (SE/C) 37.1 ± 7.4 a Prompt L-Pop (PL/C) 18.2 ± 9.9 b Scotchbond Multipurpose (SM/7) 35.0 ± 9.7 c Ca(OH)2 Single Bond (SB/7) 24.8 ± 7.1 d 7 days Clearfil SE Bond (SE/7) 37.8 ± 8.4 c Prompt L-Pop (PL/7) 18.0 ± 3.6 d Scotchbond Multipurpose (SM/30) 36.7 ± 11.3 e Ca(OH)2 Single Bond (SB/30) 26.8 ± 5.9 f 30 days Clearfil SE Bond (SE/30) 31.7 ± 6.3 ef Prompt L-Pop (PL/30) 16.1 ± 7.2 g *Same superscript means no statistical difference. 201

대한치과보존학회지 : Vol. 32, No. 3, 2007 Figure 2. Micro-tensile bond strength of 12 experimental groups. Figure 3.

Micro-tensile bond strength in group of SE.

05) (Figure 5, 6). Figure 6. Micro-tensile bond strength in group of PL. 높은미세인장접착강도를나타냈으며 (p < 0.

5 대한치과보존학회지 : Vol. 32, No. 3, 2007 Figure 2. Micro-tensile bond strength of 12 experimental groups. Figure 3. Micro-tensile bond strength in group of SM. Figure 4. Micro-tensile bond strength in group of SB. Figure 5. Micro-tensile bond strength in group of SE. 3 단계 total-etching 접착제를사용한 SM 군과 2 단계 total-etching 접착제를사용한 SB 군의미세인장접착강도는대조군과 7 일실험군, 30 일실험군에서각각차이가나타나지않았다 (p > 0.05) (Figure 3, 4). 2 단계자가부식형접착제를사용한 SE 군과 1 단계자가부식형접착제를사용한 PL 군은 30 일실험군에서미세인장접착강도가다소감소하는양상을보였으나, 통계적으로유의성은없었다 (p > 0.05) (Figure 5, 6). Figure 6. Micro-tensile bond strength in group of PL. 높은미세인장접착강도를나타냈으며 (p < 0.05), 수산화칼슘을 30 일간적용한 PL 군이 SM 군, SB 군, SE 군에비해유의성있게낮은미세인장접착강도를나타냈다 (p < 0.05). 2. 주사전자현미경관찰 주사전자현미경관찰에서상아질잡착제에따른파절양상의차이를발견할수있었다. 높은미세인장접착강도로측정된 3 단계 total-etching 접착제를사용하는 SM 군과 2 단계자가부식형접착제를사용하는 SE 군에서는 cohesive failure 의양상이나타났다 (Figure 7-10). 2 단계 total-etching 접착제를사용하는 SB 군에서는 cohesive failure 와 adhesive failure 가혼재된양상이나 202

$SEM photograph of the fractured surface of SM/C group, showing cohesive failure.$ $that fractured at the bottom of the hybrid layer. Figure 8.$ $SEM photograph of the fractured surface of SM/30 group, showing cohesive failure.$ $SEM photograph of the fractured surface of SB/C group, showing mixed failure.$ $SEM photograph of the fractured surface of SB/30 group, showing mixed failure.$ $SEM photograph of the fractured surface of SE/C group, showing cohesive failure.$

6 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 Figure 7. SEM photograph of the fractured surface of SM/C group, showing cohesive failure. The failure occurred at the bottom of the hybrid layer and there are resin tags in the dentinal tubules that fractured at the bottom of the hybrid layer. Figure 8. SEM photograph of the fractured surface of SM/30 group, showing cohesive failure. The failure occurred at the bottom of the hybrid layer and there are resin tags in the dentinal tubules that fractured at the bottom of the hybrid layer. Figure 9. SEM photograph of the fractured surface of SB/C group, showing mixed failure. The failure occurred both at the top of the hybrid layer and in the bottom of the hybrid layer. Figure 10. SEM photograph of the fractured surface of SB/30 group, showing mixed failure. The failure occurred both at the top of the hybrid layer and in the bottom of the hybrid layer. Figure 11. SEM photograph of the fractured surface of SE/C group, showing cohesive failure. The failure occurred at the bottom of the hybrid layer and exposed dentin, which was not enveloped by resin. Figure 12. SEM photograph of the fractured surface of SE/30 group, showing cohesive failure. The failure occurred at the bottom of the hybrid layer and exposed dentin, which was not enveloped by resin. 203

$대한치과보존학회지 : Vol. 32, No. 3, 2007 Figure 13. SEM photograph of the fractured surface of PL/C group, showing adhesive failure. The failure occurred between the resin and the top of the hybrid layer.$ 타났으며파절이혼성층의상부와하부에서모두관찰되었다 (Figure 11-12). 반면가장낮은접착강도로측정된 1 단계자가부식형접착제를사용하는 PL 군은 adhesive failure 의양상을보였다 (Figure 13-14).

타났으며파절이혼성층의상부와하부에서모두관찰되었다 (Figure 11-12). 반면가장낮은접착강도로측정된 1 단계자가부식형접착제를사용하는 PL 군은 adhesive failure 의양상을보였다 (Figure 13-14).

7 대한치과보존학회지 : Vol. 32, No. 3, 2007 Figure 13. SEM photograph of the fractured surface of PL/C group, showing adhesive failure. The failure occurred between the resin and the top of the hybrid layer. Figure 14. SEM photograph of the fractured surface of PL/30 group, showing adhesive failure. The failure occurred between the resin and the top of the hybrid layer. 타났으며파절이혼성층의상부와하부에서모두관찰되었다 (Figure 11-12). 반면가장낮은접착강도로측정된 1 단계자가부식형접착제를사용하는 PL 군은 adhesive failure 의양상을보였다 (Figure 13-14). 상아질접착제에따른파절양상의차이가관찰된것에반해같은상아질접착제를사용한경우대조군과실험군에서접착양상의차이는관찰되지않았으며모든군에서수산화칼슘의잔사는발견되지않았다. Ⅳ. 총괄및고안 수산화칼슘은근관치료및보존수복분야에서가장널리사용되고있는약제중의하나이다. 특히높은알칼리성에의한살균효과와상아질의재광화를유도하는특성으로치수보호를위한이장재나치수복조술시의약제및실활치표백술이후의와동소독제등다양한용도로보존수복분야와더불어근관치료분야에서도사용되고있다. 한편최종심미성접착수복에상아질접착제의사용은필수적이다. 그러나수산화칼슘은조직변성을야기하여접착성수복술식에위해한영향을미칠가능성이있어임상에서적절한선택이요망되는바, 수산화칼슘의적용여부및그적용기간이접착강도에어떠한영향을미치는가를관찰하여수산화칼슘사용후에적합한접착제의선택및접착방법을구명하고자각각다른접착과정을갖는 4 종의상아질접착제를사용하여상아질의미세인장접착강도의변화를관찰하였다. 현재널리사용되고있는상아질접착제중 3 단계 totaletching 접착제및 2 단계 total-etching 접착제는 35% 인 산을사용하여산부식및수세과정을시행하며이과정에서도말층을제거하고표층의무기질을용해시킨다. 차이점은 2 단계 total-etching 접착제의경우전통적인 3 단계 total-etching 접착제와는달리프라이머처리및접착제도포를동시에시행하여접착과정을단순화시키고시술시간을단축시켰다는점이다. 반면 2 단계자가부식형접착제및 1 단계자가부식형접착제는산성단량체에의한산부식과전처리가동시에이루어지며, 도말층이제거되지않고부분적으로탈회되어하부의상아질을용해 / 변형시켜상아질과접착하게된다 24-25). 자가부식형접착제는접착과정의단축으로시술시간을줄일수있는장점이외에도도말층을제거하지않아상아세관으로부터세관액의유출을감소시키고습윤접착과정이배제되며교원섬유의건조로인한붕괴가나타나지않아탈회층과레진침투층이일치되어술후과민반응을감소시킨다. 또한습윤접착과정의배제는기술적민감성 (technical sensitivity) 을최소화할수있다는장점을갖는다. 이러한안정성과편리함에의해자가부식형접착제에대한수요는점차증가하고있다 28-30). 4 세대접착제를사용한 SM 군과 5 세대접착제를사용한 SB 군은모두 total- etching 계열의접착제로 35% 인산을사용하여산부식및수세과정을시행하며이과정에서도말층을제거하고표층의무기질을용해시킨다는공통점을가진다. 4 세대와 5 세대상아질접착제의차이점은 2 단계접착과정의 one-bottle system 인 SB 군의경우, 프라이머가없어산성을갖는기능성단량체가상아질과직접접착한다는점이다 24-25). 반면 5 세대접착제를사용한 SE 군과 6 세대접착제를사용한 PL 군은모두자가부식형접착제로산성단량체에의한 204

8 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 산부식과전처리가동시에이루어지며, 도말층이제거되지않고부분적으로탈회되어하부의상아질을용해 / 변형시켜상아질과접착한다. 이때도말층이충분히부식될수있도록충분한산도를지녀야하며, 특히 6 세대상아질접착제가포함하는친수성 / 이온성산성단량체들 (MAC-10, pyrophosphate, 4-MET, phosphoric acid esters, pyro- EMA) 의산도는본질적으로 5 세대상아질접착제보다도높은것으로알려져있다 24-25). 수산화칼슘은높은알칼리성으로파골세포가분비하는젖산을중화시켜파골세포의작용을감소시키는것으로알려져있다 15). 따라서수산화칼슘에의한조직변성이접착과정에있어서높은산성을띄는 Single Bond, Clearfil SE Bond 와 Prompt L-Pop 을사용한 SB 군, SE 군및 PL 군에서산 - 염기반응에의한중합반응방해나접착강도감소를야기할수있을것으로예상하였으며실제로 SE 군과 PL 군에서는수산화칼슘을 30 일적용한경우접착강도가약간감소되어나타났다. 그러나 3 단계 total-etching 접착제를사용한 SM 군뿐아니라 SB 군, SE 군과 PL 군의경우, 대조군과접착강도의유의성있는변화는나타나지않았다. 따라서수산화칼슘의단기간사용에의한상아질의조직변성은접착양상이나강도를변화시킬만큼접착강도의변화는크지않았다고생각할수있다. 전술한바와같이 Windley 등 22) 도수산화칼슘의단기간사용이 2 단계 total-etching 접착제인 Single Bond 와 Prime & Bond NT (Dentsply Caulk, Milford, USA) 의접착강도에영향을미치지않는다고밝힌바있으며, Andreasen 등 27) 의연구에따르면수산화칼슘을근관내에 30 일간적용한경우, 치근의파절저항에아무런영향이없었으나, 60 일이상적용한경우에치근의파절저항이감소하였고, 1 년간적용한경우 50% 에달하는파절저항이감소될수있음을수산화칼슘의알칼리성에의해상아질의유기질구조가약화되기때문이라고보고하였다. 이를토대로수산화칼슘에의한상아질의조직변성은그효과가서서히나타난다고생각할수있으며본연구와같이단기간 (7 일또는 30 일 ) 적용하는경우에는상아질접착제의종류나접착기전에관계없이위해효과를나타내지않는다고생각할수있다. 따라서보다장기간수산화칼슘을적용하는경우, 접착강도가감소될것을예상할수있으나, 실제로근관치료시에도근첨형성술등을시행하는경우를제외하고는 60 일이상수산화칼슘을적용하는경우가드물며보존수복술식의경우, 대부분빠른시일내에최종수복이이루어지므로수산화칼슘의장기적인사용에따른접착강도의감소할가능성은사실상임상에서는드물다. 주사전자현미경관찰결과, 높은접착강도를보인 SM 군, SE 군에서는 cohesive failure 양상이, 전술한두상아질접 착제에비해낮은접착강도를보인 SB 군에서는 cohesive failure 와 adhesive failure 가혼재된양상이, 가장낮은접착강도를보인 PL 군에서는 adhesive failure 양상이나타났다. 이는 Shono 등 23) 의연구결과에따르면, 30 MPa이상의접착강도를나타내는시편의경우, 주사전자현미경으로관찰한파단면에서사용된접착제나술자에관계없이 cohesive failure 와 adhesive failure 가혼재된양상이나타나며낮은접착강도를보이는경우에서는 adhesive failure 가많이나타난다고하였다. 이는본연구에서의주사전자현미경관찰결과와도부합하는것으로접착제들사이에나타난파단양상의차이는접착강도의차이에의한것이다. 또한각각의접착제에서대조군과실험군사이에차이가발견되지않은것으로보아수산화칼슘이파단양상에영향을미치지는않았다고생각할수있다. Shono 등 23) 의연구에서는또한시편제작중파절된시편들의파절면에서잔사등의이물소견을보고하였는데, 따라서수산화칼슘의단기적용시접착강도의유지는수산화칼슘적용여부나기간보다도수산화칼슘잔사의완전한제거여부에좌우된다고볼수있다. Total-etching 계열접착제의경우, 부가적인산부식및수세과정이수반되므로보다효과적인제거가가능할것으로생각되며, self-etching 계열접착제의경우, 부가적인산부식및수세과정이없으므로수산화칼슘제거시보다주의가필요할것으로생각된다. Ⅴ. 결론 상아질에수산화칼슘의적용여부에따라 7 일과 30 일간적용한실험군과수산화칼슘을적용하지않은대조군과의미세인장접착강도의변화를분석하고적절한상아질접착제의선택을위하여 4 종의상아질접착제 Scotchbond Multipurpose (SM), Single Bond (SB), Clearfil SE Bond (SE), Prompt L-Pop (PL) 를사용한후복합레진 (Z-250) 을상아질에적층하고, 미세인장접착강도를측정, 분석하고주사전자현미경을이용하여접착계면을관찰한결과다음과같은결론을얻었다. 1. 대조군과 7 일실험군에서 SM, SE 가 SB, PL 에비하여높은접착강도를나타내었다 (p < 0.05). 2. SM 과 SB 를사용한실험군의접착강도는대조군과유의성있는차이를보이지않았다. 3. SE 와 PL 을사용한 30 일실험군에서접착강도가다소감소하는양상을보였으나, 통계학적유의성은없었다. 4. SM 과 SE 에서는 cohesive failure 양상이, SB 와 PL 에서는 adhesive failure 의양상이나타났으나, 대조군과실험군에서접착양상의유의한차이는없었다. 205

9 대한치과보존학회지 : Vol. 32, No. 3, 2007 이상의연구결과에서단기간 (7 일또는 30 일간 ) 의수산화칼슘적용은상아질접착제의접착과정의차이에따른변화를나타내지않는것으로평가되었다. 따라서현재사용되고있는상아질접착제들은올바른적용방법을준수할경우, 수산화칼슘적용여부와는무관하게임상적적용에안정성이있다고사료된다. 참고문헌 1. Orstavik D. Antibacterial properties of endodontic materials. Int Endod J 21(2): , Chong BS and Pitt Ford TR. The role of intracanal medication in root canal treatment. Int Endod J 25(2): , Unemori M et al., Composite resin restoration and postoperative sensitivity: clinical follow-up in an undergraduate program. J Dent 29(1):7-13, Ulusu T et al., Comparison of the effect of insertion techniques of a resin composite on dentinal adaptation of two visible light-cured bases: direct evaluation versus a replica technique. Quint Int 27(1):63-68, Cox CF and Suzuki S. Re-evaluating pulp protection: calcium hydroxide liners vs. cohesive hybridization. J Am Dent Assoc 125(7): , Suliman AA and Chan KC. Microleakage between different types of base materials. Prosthet Dent 67(2): , Staehle HJ et al., The marginal sealing of composite inlays with different cavity liners. Schweiz Monatsschr Zahnmed 102(10): , Fitzgerald M and Heys RJ. A clinical and histological evaluation of conservative pulpal therapy in human teeth. Oper Dent 16(3): , Papadakou M et al., Adaptation of two different calcium hydroxide bases under a composite restoration. J Dent 18(5): , Peliz MI et al., Scanning electron microscope analysis of internal adaptation of materials used for pulp protection under composite resin restorations. J Esthet Restor Dent 17(2): , Ersin NK and Eronat N. The comparison of a dentin adhesive with calcium hydroxide as a pulp-capping agent on the exposed pulps of human and sheep teeth. Quint Int 36(4): , Subay RK and Demirci M. Pulp tissue reactions to a dentin bonding agent as a direct capping agent. J Endod 31(3): , Scarano A et al., A. Direct capping with four different materials in humans: histological analysis of odontoblast activity. J Endod 29(11): , Cox CF et al., Biocompatibility of surface-sealed dental materials against exposed pulps. J Prosthet Dent 57(1):1-8, P.C. Foreman and I.E. Barnes. A review of calcium hydroxide. Int Endod J 23: , Eidelman E et al., Remineralization of carious dentin treated with calcium hydroxide. J Dent Child 32(4): , Kehoe JC. ph reversal following in vitro bleaching of pulpless teeth. J Endod 13(1):6-9, de Oliveira LD et al., Sealing evaluation of the cervical base in intracoronal bleaching. Dent Traumatol 19(6): , Lambrianidis T et al., Effect of calcium hydroxide as a supplementary barrier in the radicular penetration of hydrogen peroxide during intracoronal bleaching in vitro. Int Endod J 35(12): , Andreasen JO and Kristerson L. The effect of extraalveolar root filling with calcium hydroxide on periodontal healing after replantation of permanent incisors in monkeys. J Endod 7(8): , Chung HA et al., Adhesion of glass-ionomer cement sealers to bovine dentin conditioned with intracanal medications. J Endod 27(2):85-88, Windley W Ⅲ et al., The effect short-term calciun hydroxide treatment on dentin bond strength to composite resin, Dent Traumatol 19(2):79-84, Shono Y et al., Regional measurement of resin-dentin bonding as an array. J Dent Res 78(2): , Tay FR and Pashley DH. Aggressiveness of contemporary self-etching systems. I: Depth of penetration beyond dentin smear layers. Dent Mater 17(4): , 장영인, 최경규, 박상진. 복합레진에대한자가부식형접착제의적합성에관한연구. 대한치과보존학회지 31(in process), Tanumiharja M et al., Microtensile bond strengths of seven dentin adhesive systems. Dent Mater 16(3): , Andreasen JO and Kristenson L. Long-term calcium hydroxide as a root canal dressing may increase risk of root fracture. Dent Traumatol 18: , Pioch T et al., The nanoleakage phenomenon: influence of moist vs dry bonding. J Adhes Dent 4(1):23-30, Swift EJ Jr. Dentin bonding: what is the state of the art? Compend Contin Educ Dent 22(12 Suppl):4-7; quiz 18, Perdigao J. Dentin bonding as a function of dentin structure. Dent Clin North Am 46(2): ,

10 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 국문초록 수산화칼슘적용에따른상아질접착제의접착강도변화에관한연구 박노훈 박상혁 최기운 박상진 * 경희대학교대학원치의학과치과보존학교실 본연구는다양한접착과정과기전을지닌 4 종의상아질접착제를이용하여수산화칼슘의사용여부및그적용기간이접착강도에미치는영향을측정및평가하고주사전자현미경을이용한접착계면의관찰을통해복합레진수복이나레진시멘트를이용한수복물접착시에적절한상아질접착제의선택과사용방법을알아보고자시행하였다. 치수강에근접한상아질표면을노출시킨후, Ca(OH)2 를생리식염수와혼합하여실험군치아 24 개의상아질표면에적용한후, IRM (Intermediate Restorative Material, Dentsply Caulk, Milford, USA) 으로적용된수산화칼슘및변연부위의상아질과법랑질모두를밀폐하여 36.5 증류수에서실험기간 (7 일및 30 일 ) 동안보관하였다. Scotchbond Multipurpose, Single Bond, SE Bond and Prompt L-Pop 등 4 종의상아질접착제를제조사의지시에따라적용하고복합레진을 3 회에나누어총 5 mm높이로적층한뒤각층마다 20 초씩광조사를시행하였다. Universal testing machine 을이용하여 1 mm /min 의 crosshead speed 로하중을가하여미세인장접착강도를측정하고파단면을주사전자현미경으로관찰하였다. 이상의연구결과에서단기간 (7 일또는 30 일간 ) 의수산화칼슘적용은상아질접착제의접착과정의차이에따른변화를나타내지않는것으로평가되었다. 주요어 : 수산화칼슘, 상아질접착제, 복합레진, 상아질접착강도, 미세인장접착강도, 주사전자현미경분석 207

법랑질에대한 total etching과 self-etching 접착제의산부식효과와미세인장결합강도 법랑질에대한 total etching과 self-etching 접착제의산부식효과와미세인장결합강도 오선경 허복 * 김현철부산대학교치과대학보존학교실 ABSTRACT THE ET

법랑질에대한 total etching과 self-etching 접착제의산부식효과와미세인장결합강도 법랑질에대한 total etching과 self-etching 접착제의산부식효과와미세인장결합강도 오선경 허복 * 김현철부산대학교치과대학보존학교실 ABSTRACT THE ETCHING EFFECTS AND MICROTENSILE BOND STRENGTH OF TOTAL