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Biomaterials Research (2007) 11(1) : 43-50 Biomaterials Research 7 The Korean Society for Biomaterials ³ 3MA kj p v s w e e p Preparation and Characteristics of Dental Pit and Fissure Sealants with Novel 3MA Methacrylated Prepolymers Á Á½ Áw * Jun Sik Son, Kwideok Park, Jae-Jin Kim, and Dong Keun Han* Š Š e f g Biomaterials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Korea (Received December 18, 2006/Accepted February 7, 2007) As an alternative to 2,2-bis[4-(2'-hydroxy-3'-methacryloyloxypropoxy) phenyl]propane (Bis-GMA) that contains Bisphenol A, a possible endocrine disrupter, novel multifunctional methacrylated prepolymers, 80-3MA and 4000-3MA mix (2MA:3MA:4MA mixture=45:45:10 wt%), were synthesized and then dental pit and fissure sealants composed of the novel prepolymers, diluent, and inorganic filler were prepared. The viscosities of the prepolymers were much lower than that of the Bis-GMA control. From the results of 1 H-NMR analysis, the chemical structures of the prepolymers were similar to that of Bis-GMA. In addition, the polymerization shrinkage, photoconversion, polymerization depth, and diametral tensile strength of the dental sealants formulated with 80-3MA and 4000-3MA mixture prepolymers exhibited comparable to or better than those of the existing Bis-GMA-based one. These results suggest that the novel 3MA methacrylated prepolymers which have no endocrine disrupter can be an alternative to Bis-GMA and be applicable to biocompatible dental materials. Key words: Dental pit and fissure sealant, Endocrine disrupter, Bis-GMA, Bisphenol A, Methacrylated prepolymer, 3MA mixture e h g( ƒ, pit and fissure sealant) d f hx f t d f f h Š x d (vx)f Š e Š d Šg f. 1) x h gf e l d f (prepolymer) j Œ f f dš ff Œ f f d Š jšš f dš f. f f ft Š Š f Š f f ihf d l f jš ff f Šff u jf f ghf l f u g f dš f. 2-4) g d f Œ x h gf e lf j 2,2-bis[4-(2'-hydroxy-3'-methacryloyloxypropoxy)phenyl] propane (Bis-GMA)f j f Š ff 1,6-bis(methacryloyloxy-2-ethoxycarbonylamino)-2,4,4-trimethylhexane (UDMA)f dš d f. x h g Bis- GMA hr f d Š Œ Œ *sf hf: dkh@kist.re.kr f if f ~ l h x x Š d ~} fƒ 3:1f e Œ ŠŠ dš hf triethylene glycol dimethacrylate (TEGDMA)f fh ŒŠŠ dš f. 5-7) hf TEGDMAf t x h gf h l fl h gf h, jš ff f h jš f v h f ~. f Š 8) hf Š eš Bis-GMA ftf f i Œ z h vf hf d f jf f f ff h ƒ f l hhf ~ f. h g d e lf f 9) h l jš ~ vf h h g dš hhš h ƒ f g Š f jdš Š f. Š x h g e l f hf vhh(filler) t Š d Š f. vhhf t h gf h ƒ f f f x h Š f l Š h gf ~ ff, i f f d Š ghf f. 10) Š, u Š ŒŠ hˆ Š Œ f 43

44 j Á Á gláš hf } h f d ƒ f e v Œ Œ f l(endocrine disrupter) hf fl eš f Š ft x hf e Š Š f ŒŠ l l f Š f l Š f. 11) Œ t(environmental protection agency, EPA) lf t f Š e l hf ihš t Œ f,, f, Šfd f Š df l hfš f Š i f lš eš f lšš ff Œ Œ Š f l h Š hf ft vš iš hf sf Š f. f Š Œ Œ f f 12) f f j Š ff ŒŠh i tf Œ Š t d h hf Œ f f Œ ~f f Œ, f hš, Š f Œ, f f e Š f fœf f. ƒ f Œ Œ j 13) A(Bisphenol A) Š lf, 0.1 ppb h ~ f x ~ hf l xf z g d l f d, f de, gg f d x fƒ f d vx d x h g, vxx x d Š l, x d hrh ƒ f x g d Œ j f f d f. fj Š f x h gf h 14-17) f e lf Bis-GMA dš ff f f A Š f x d f fš ft f x f f hš. f Š Bis-GMA e Š h ƒ f h Œ Œ f A Še fl f d ftxœh x h gd e lf Š h ŠdŠ hf. f f f A Še fl f Bis-GMA e Š ŒŠ i d 2 ~} fƒ (bifunctional methacrylated prepolymer) Š Š f fdš e ƒ hiš f f ŒŠh ƒ f Š Bis-GMA tš f d Œd fff ŒfŠ f. 18) Œ Œ f A Še Bis-GMA tš f hh f x h g hiš eš 2i f d (3-4 ) ~} fƒ (multifunctional methacrylated prepolymer) Š Š f, f Š 3MA fdš h jš t vhh i ŒŠŠ x h g hiš. Š f e, h ŒŠh i hi x h gf h h f whš controlf Bis-GMA, Š. 2i f ~} fƒ Š Š e Š ŒŠ fsœš (f )f Bisphenol F type ŒŠ (YSLV-80XY) Diphenyl ŒŠ (YX-4000H)f dš. ŒŠ f methacrylationf eš Aldrich f methacrylic acid methacrylic anhydride dš f, ft jš lh TCI f 4-dimethylaminopyridine (DMAP) Aldrich f 4-methoxyphenol (MEHQ) butylated hydroxytoluene (BHT)f dš. e ƒ f h t Aldrich f TEGDMA UDMA dš, vhh ff} 40 nmf x(ox50, Degussa Co., Germany) dš. x f vhhf f Aldrich f 3-(trimethoxysilyl)propyl methacrylate (γ-mps) s Š f f lš dš. l h h(œeh) Aldrich f camphorquinone (CQ) ethyl p-dimethylamino benzoate (EDMAB) dš. Š control Aldrich f Bis-GMA (Figure 1(A)) dš f, df f 1 hˆf hh f dš. 3MA kj p v s w Figure 1(B) l Œ~f ŒŠ methacrylic acid fdš d Œ~f ~} fƒ f Š ~ f f f Š f f h Š f f Š Š. 18,19) h A ŠeŠ fl f ŒŠ f v l Š methacrylic acid fš 2 ~} fƒ (bifunctional methacrylate) Š Š f Š 2 methacrylic anhydride fš 2 f j igš 2 f (-OH) j Š f ef ~} fƒ xœ ~ f 3 4 f ~} fƒ Š Š. hf X=CH 2 f Bisphenol YSLV-80XY ŒŠ f v l Š ~} fƒ(fš 80-3MA mix xš) f Š f f. ŒŠ f YSLV-80XY (101 g) methacrylic acid (82 g) 90 o C 9 Œ ~ t f DMAP (0.35 g) jš lhf MEHQ (0.36 g) t Š ff methylene chloride f f HCl NaOH fdš r sš e d h Š f Š f h f Š eš jš lhf MEHQ BHT t Š uihf 2 f ~} fƒ o 2 ~} fƒ(fš 80-2MA xš). Š Š 80-2MA (76 g) methylene chloride Biomaterials Research 2007

3MA ~} fƒ fdš x d x h gf hi ƒ 45 (200 ml) f triethylamine (9.8 g) methacrylic anhydride (31.4 g) t Š f 1f fš 80-2MAf Š f f work-upš uih f 80-3MA mix Š Š. l 80-3MA mix ethyl acetate n-hexanef 50:50f j ŒŠ h f dš y (column)f dš i Š 2, 3 4 ~} fƒ 45:45:10f j ~ f f 80-3MA mix Š. Š X=nonef Diphenyl YX- 4000H ŒŠ f v l Š 4000-2MA 4000-3MA mix ~} fƒ fš f Š Š. e Table 1 ~ i f, Š Š ~} fƒ (10~50 wt%) dš x d e ƒ hiš. l, h v eš hf TEGDMA 20 wt% dš f, f l hf CQ h(œeh)f EDMAB 1 2 wt% dš. Š jš ff Œ eš jš tf UDMA 20~60 wt% t Š f, vhh x 7 wt% dš. e ƒ f f Š eš Bis-GMA BG, 80-3MA mix 80f, 4000-3MA mix 4000f x Š f i f f ~., BG-324f d Bis-GMA prepolymerf Š f 30 wt%, TEGDMA 20 wt%, UDMA 40 wt% ŠeŠ f ff f Š. p Š ~} fƒ f h Brown f h fdš prepolymer controlf Bis-GMA 25 whš, ŒŠh i chloroform-d d dš proton nuclear magnetic resonance ( 1 H-NMR, Gemini 200 MHz, Varian) Fourier transform infrared (FTIR, IFS 66 spectrometer, Bruker) spectrometer Š. x h gf Œ jš v f Linometer RB404 Table 1. Preparation of dental sealants with various organic matrices Sealant code a Prepolymer TEGDMA UDMA CQ EDMAB Silica BG-324 30(BG) 20 40 1 2 7 80-324 30(80) 20 40 1 2 7 4000-324 30(4000) 20 40 1 2 7 80-522 50(80) 20 20 1 2 7 4000-522 50(4000) 20 20 1 2 7 80-126 10(80) 20 60 1 2 7 4000-126 10(4000) 20 60 1 2 7 a BG: BS-GMA, 80: 80-3MA mix, and 4000: 4000-3MA mix. (R&B, Inc., Korea) fdš whš. hœ (degree of photoconversion)f FTIRf fdš whš f f d ƒ } 1608 cm -1 f i hf fj Š } 1638 cm -1 f l i methacrylatef fj Š }, jš h f } hf hf Š h Š. 20) x h gf jš f(polymerization depth) 20 mmf f l e Œf 20t jšf ŠŠ jš f Š. e(water absorption) Š dš (water solubility) l f 20 mm, 1.2 mmf f Œ ~, Œ f 37 o C xš j Œ f f j f whš (m 1 ), 37 o C el l 7f xl f f h Š j f wh(m 2 ) Š f 37 o C xš j Œ f f j f wh(m 3 )Š (1) (2) Š. Water absorption = [(m 2 ) (m 3 )] / V 1) Water solubility = [(m 1 ) (m 3 )] / V (2), V f th(volume of sample)f. h f hfg (diametral tensile strength, DTS) l 10 mm 5mmf f hfš, ISO 5833 fg fdš 0.5 mm/minf f h l f whš Š. š 3MA kj p v s w yw Figure 1(A) g x h gf d f Bis-GMAf ŒŠ i f ~ f f ŒŠ i j A ŠeŠ f f ŒfŠ f. 2i f d ~ } fƒ f 80-3MA mix 4000-3MA mixf Š ~ Figure 1(B) ŒŠ i Bis- GMA e Š A ŠeŠ fl f f f. f Š 3MA Bis-GMA x h gf Œ Œ hf w i hš ff f f f h h ƒ Bis-GMA dš x h g f rf ff f w. Table 2 Š Š 3MA ~} fƒ f e h controlf Bis-GMA Š f. h 2 ~} fƒ f 80-2MA 4000-2MAf ef 90% f f ~ f f 80-3MA mix 4000-3MA mix 2 f 80-2MA 4000-2MA Š 70% fš ef h l f. Š 2i f h 2 6- Vol. 11, No. 1

46 j Á Á gláš Figure 1. (A) Chemical structure of Bis-GMA containing Bisphenol A and (B) synthetic scheme of multifunctional methacrylated prepolymers (80-3MA mix and 4000-3MA mix). Table 2. Synthetic yield and viscosity of mathacrylated prepolymers Prepolymer Yield Viscosity (cps) (%) BG: Bis-GMA control 12,000 80: Methacrylated 80-2MA/80-3MA mix 90/65 4,800/500 4000: Methacylated 4000-2MA/4000-3MA mix 92/68 6,500/750 10 h f f f, ƒ Bis-GMA 12,000 cps f Š 80-3MA mix 4000-3MA mix 500 750 cps j f f ~. f Š 3MA Bis-GMA Š fš Šf h Œ f Š Š Š f } 2 f h ~ f. x h gf Bis-GMA hr f d Š Œ f if f ~ l h x x Š hf l f. h jf eš ~} fƒ hf TEGDMA ŠŠ dš f d fl f Š h f thš, jš, jš v l hhf l f. 7,8) Š Š ~} fƒ Bis-GMA hf h j hf f jf x f x i ~ ff f ƒ 2 h f f 80-3MA mix 4000-3MA mix x h gf ŒdŠ lš f. Figure 2 ŒŠ f Bisphenol YSLV-80XY (A) Š Š 80-3MA mix (B) f 1 H-NMR ƒ f ~ f. h Š v lf Bisphenol YSLV- 80XY ŒŠ f ƒ } 6.9 ppm h, 4.0 4.2 ppm h f -OCH 2, 2.2 ppm h xœ f -CH 3, 2.9 ppm f -CH 2.8 ppm -CH 2 ~ f ŒfŠ. Š 80-3MA mix Figure 1(B) ~ Œ Š f o f 2 f fj Š fš 5.7 Biomaterials Research 2007

3MA ~} fƒ fdš x d x h gf hi ƒ 47 Figure 2. Typical 1 H-NMR spectra of (A) Bisphenol YSLV-80XY and (2) 80-3MA mix. 6.2 ppm f (a) 2.0 ppmf -CH 3 (b), 5.2 ppm (c) ~} fƒ f f -OH ~} xœ d } ~ f ŒfŠ. Š FTIR 3500 cm -1 f fš } Šf Š Š ~} fƒ f 80-3MA mixf Š f g f hff ŒfŠ f. 18) f f ŒfŠ 4000-3MA mixf Š 80-3MA mix e Š ~. e p Figure 3 Bis-GMA, 80-3MA mix 4000-3MA mix 30 wt%, hf TEGDMA 20 wt%, jš t 40 wt%, vhhf x 7 wt% ŠeŠ BG-324, 80-324 4000-324 x h gf Œ jš vf Œ ~ f h g } rf f 30t f jšf f lf ŒfŠ f. Bis-GMA Š eš BG-324 h g Œ f l jš vf g f f ~ f 80-3MA mix ŠeŠ 80-324 h g 4000-3MA mix ŠeŠ 4000-324 h g BG-324 h g Œ l jš vf ~ f ŒfŠ f. Š Š ~} fƒ Bis-GMA e Š ŒŠ i ll A Še fl f h xœ f f ƒ lf. Kim fš h f xœf t e ff fe l ~ f Š tf fe f Œ jš l ~l j Š v f ~ e Š f fdš ff Š f. f x h g d 21) d ~} fƒ h 4 xœ f Œ f Bis-GMA ŠeŠ l jš vf Ž l f f f. Table 3f controlf Bis-GMA f 80-3MA mix 4000-3MA mixf dš gf TEGDMA j Š tf UDMA vhh i ŒŠŠ x h gf hœ jš v f ~ f. f hf jš vf d f ŒŠh l i t ŒŠŠf ~ ff j Š v f f jšf g l ui h f j f. f f ŒŠi f uhœš f f h ~ f. h 22) Bis-GMA 30 wt%, TEGDMA 20 wt% UDMA 40 wt% ŠeŠ BG-324 h gf hœ jš v f 50% 8.0% f, 80-3MA mix ŠeŠ 80-324 h g 52% 4.2%, 4000-3MA mix ŠeŠ 4000-324 h g 50% 7.0% BG-324 h g hœ f i f jš v f l. Š hf TEGDMAf Š f fš Š jš tf Š f Œ ~ x h g Bis-GMA ŠeŠ 80-3MA mix ŠeŠ h g 4000-3MA mix ŠeŠ hœ f f jš v f f ~. f Bis-GMA ŠeŠ x h g ŠeŠ h g hœ Figure 3. Curing time and polymerization shrinkage of dental sealants; (a) BG-324, (b) 4000-324, and (c) 80-324. Table 3. Potoconversion and polymerization shrinkage of various dental sealants Sealant code Photoconversion (%) Polymerization shrinkage (%) BG-324 50 8.0 80-324 52 4.2 4000-324 50 7.0 80-522 49 4.8 4000-522 55 7.5 80-126 56 4.7 4000-126 52 7.0 Vol. 11, No. 1

48 j Á Á gláš jš v d Š f f h Š f h xœ ff fš f h fš f f e f dfš Š f f f l Š f f ƒ 80-3MA mix Š eš h g 4000-3MA mix ŠeŠ Š f } hœ jš v f d Šf f f. Figure 4 controlf Bis-GMA ŠeŠ x h gf jš f ~ f. f Bis-GMA ŠeŠ BG-324 h g 9 mmf jš f ~ f 80-3MA mix ŠeŠ h g 11-12 mm e, 4000-3MA mix ŠeŠ h g 10-11 mm e BG-324 h g 10-30% h f jš f ~ f ƒ 80-3MA mix ŠeŠ h g g f jš f ~. f 80-3MA mix Bis-GMA 4000-3MA mix hf f h f f h f ŠeŠ x h g hœ, jš v jš f Bis-GMA ŠeŠ i d Š ƒ f f f Š f x h g hi Š dš f ŒŠh i h h g f h ƒ } f x f f. Figure 5 controlf Bis-GMA 30 wt%, TEGDMA 20 wt%, UDMA 40% vh h 7 wt% ŠeŠ x h gf f ~ f. f hf x h g d e lf f Š jš h gf f hšš. l, jš h g fš e vhh f Š f Šh vhh ff f ~ hš f h ƒ f Šl Š, f e ff h g f f f eff Š. f Figure 5. Water absorption of dental sealants. Š Œ h gf dœh ƒ f elš f d jdš d Š f. Figure 5 f s x h g 15f f Œf f f ff Bis-GMA ŠeŠ BG-324 h g 22 µg/mm 3 f f ŠeŠ h gf d 15-16 µg/mm 3 e BG-324 30% h f ef. f Š x f Š ~} xœ f f f hf Šl hi x h gf l f. Figure 6f x h gf Š dš ~ f Figure 5 e Š f ~. Bis-GMA Še Š BG-324 h gf dš 2.55 µg/mm 3, f f Š rf ff Bis-GMA:TEGDMA:filler = 15:10:75f Š lf 19.8±1.7 µg/mm 3 f 2.10±0.12 µg/mm 3 f dš Kim 23) f e Š f f 80-3MA mix ŠeŠ Figure 4. Polymerization depth of dental sealants. Figure 6. Water solubility of dental sealants. Biomaterials Research 2007

3MA ~} fƒ fdš x d x h gf hi ƒ 49 80-324 h g 1.4 µg/mm 3, 4000-3MA mix ŠeŠ 4000-324 h g 1.5 µg/mm 3 BG-324 Š dš 40% h } f f ~. x g f Š dš f hf x h g Še f ŒŠhf ŠŠl f Š f Š Š f dš fiš. ŠeŠ x h g Bis-GMA ŠeŠ f dš ~ f Bis-GMA Š fd f ~} hf f hœ f Bis-GMA ŠeŠ Š Š f f h g h igš f f fš f l f Š ŒŠ Š f f i Š dš f l. hf ŠeŠ x h g Bis-GMA ŠeŠ f dš f h g Š f dvf l f w f f d x h h dš lš Š f. e» p Figure 7f controlf Bis-GMA ŠeŠ x h gf hfg (DTS) ~ f. Bis- GMA ŠeŠ BG-324 h gf hfg 31 MPaf f f 80-3MA mix ŠeŠ h g 36-40 MPa, 4000-3MA mix ŠeŠ f 32-36 MPa BG-324 f f. ƒ hf TEGDMA vhhf Š f fhš jš tf UDMA 60 wt% ŠeŠ h g, j 80-2MA mix ŠeŠ 80-126 h g g f hf g f ~. f Bis-GMA Š ihf d e Šl d ŠeŠ x h g f hœ jš f, f jš v f l h ƒ f ff, ƒ Š Figure 7. Diametral tensile strength (DTS) of dental sealants. f h controlf Bis-GMA d d e ŒŠ f ŒŠf g f h hf jš f g lš vhhf h d dfš Š h f f f jš tf UDMAf f Š f h gf Š f d lh l Š hfg l Š f. ŠeŠ x h g controlf Bis-GMA ŠeŠ h d Š h ƒ f ff ŒfŠ f. g x h gf d f Bis- GMA tš f A ŠeŠl f d 2i f ~} fƒ f 80-3MA mix 4000-3MA mix Š Š f f 3MA hf TEGDMA, jš tf UDMA vhhf x ŒŠŠ x h g hf hiš. Š controlf Bis-GMA e Š ŒŠ i l h d x h g h i e ŒŠ vhh ŒŠŠ Ž e Š. d 3MA dš hi x h g, Š j 4000-3MA mix f h l 80-3MA mix dš hi h g controlf Bis-GMA dš hi Š h h ƒ f e Š d Š f ~ f, ƒ Š e dš hf f f ~. hi x h g x df Œ dš hšš Š x h g hi d A ŠeŠl f d Bis- GMA tš f hš i thš x g tg xœ d f g Œdf Š f. f KIST Š Œ (2E19220)f f hf f. š x 1. M. J. Hicks and L. M. Silverstone, Fissure sealants and dental enamel, A histological study of microleakage in vitro, Caries Res., 16, 353-360 (1982). 2. R. Labella, M. Braden, R. L. Clarke, and K. W. M. Davy, THFMA in dental monomer systems, Biomaterials, 17, 431-436 (1996). 3. J. W. Stansbury and J. M. Antonucci, Dimethacrylate monomers Vol. 11, No. 1

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