• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.289-302
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• 1995

The purpose of this study was to estimate the shear bond strength and observe the fractured and interfacial surfaces of various dentin bonding agents used conjunction with a visible light cured composite. The senentytwo human premolars and molars extracted due to periodontal or orthodontic reasons were used and randomely divided into six groups. All the prepared dentin surfaces were treated with Superbond D-liner, Scotchbond Multi-Purpose, All-Bond 2 and Prisma Universal Bond 3 accroding to the manufacturer's instructions. Six specimens were then demineralized in 10 % HCl for 24 hours and the other six specimens were not demineralized in order to observe the interfacial surfaces with Hitachi X-450 SEM at 25Kv. Also shear bond strength were obtained using an Instron Testing Machine with a crosshead speed of 1mm/min. The following results were obtained : 1. Although shear bond strength of Superbond D-Liner(17.35 MPa) and Scotch-bond Multi-Purpose group(17.29 MPa) were higher than the All-Bond 2(12.80 MPa) and Prisma Universial Bond 3 (13.43 MPa), there were no significant statistic differences in the shear bond strength between 4 groups.(P<0.05) As a result of etching to dentin in Prism a Universial BOND 3 experimentally, the resin tag was formed, but shear bond strength was decreased. 2. The resin tag into the opened dentinal tubule was formed in Superbond D-Liner, Scotchbond Multi-Purpose, All-Bond 2(etching) and Prisma Universial Bond 3(etching), but not in the All-Bone 2 and Prism a Universial Bond 3(non-etching). 3. Strong, durable bonds between dentin and dentinal bonding agents are essential, not only resin tag into the dentinal tubules, but also hybrid layer.

• Journal of Periodontal and Implant Science
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• 제26권4호
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• pp.873-887
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• 1996

Platelet-derived growth factor(PDGF) is one of the polypeptide growth fators. PDGF has been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. Recent studies indicated that demineralized root surface as the primary site for growth factor application has advantages over other application method, especially due to binding capacity of growth factor for exposed matrix component of deminera1ized dentin surface. The purpose of this study is to evaluate optimal application time of PDGF-BB on proliferation of human gingival fibroblasts using deminera1ized dentin surface as primary application site. Human gingival fibroblasts and dentin slabs were prepared from the first premolar tooth extracted for the orthodontic treatment, cells were cultured in DMEM/I0% FBS at the $37^{\circ}C$, 5% CO2 incubator. All of the dentin slabs were preconditioned with Tetracycline HCI(100mg/ml) solution and rinsed in PBS. In the cell proliferation experiment, experimental group was immersed in DMEM containing 10% FBS, 50ng/rnl PDGF-BB during different time(30sec, 1, 2, 4, 8 minutes) and dried. Cells at concentration of $1{\times}10^5$cells/ml were seeded in each culture well which contained dentin slabs and incubated for 6 hours. Then, all of the dentin slabs were moved into new 24 well culture dish and incubated for 24, 48, 72 hours. The cell counting was done by hemocytometer with inverted phase contrast microscope after trypsinization. The results were as follows : The application of PDGF-BB for 1, 2 min slightly increased the number of gingival fibroblasts, and the application of PDGF-BB for 4, 8 min prominently increased the number of gingival fibroblasts. The application of PDGF-BB for 4 min showed maximum proliferation rate of gingival fibroblasts at 24, 48, 72 hours, and the application of PDGF-BB for 8 min showed less proliferation rate of gingival fibroblasts compared to the application of PDGF-BB for 4 min at 24, 48, 72 hours. In conclusion, the application of PDGF-BB for 4 min appeared to be optimal to obtain maximum proliferation of gingival fibroblasts using demineralized dentin surface as primary applicaton site of PDGF-BB.

• International Journal of Oral Biology
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• 제42권4호
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• pp.203-211
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• 2017

The aim of this study was to evaluate the role of demineralized and particulate autogenous tooth, and interleukin-6 in bone regeneration. A demineralized and particulate autogenous tooth was prepared and human osteoblast-like cells (MG63) and human osteosarcoma cells were inoculated into the culture. The rate of cell adhesion, proliferation and mineralization were examined, and the appearance of cellular attachment was observed. An 8 mm critical size defect was created in the cranium of rabbits. Nine rabbits were divided into three groups including: An experimental group A (3 rabbits), in which a demineralised and particulate autogenous tooth was grafted; an experimental group B (3 rabbits), in which a demineralized, particulate autogenous tooth was grafted in addition to interleukin-6 (20 ng/mL); and a control group. The rabbits were sacrificed at 1, 2, 4 and 6 weeks for histopathological examination with H-E and Masson's Trichrome, and immunohistochemistry with osteocalcin. The cell-based assay showed a higher rate of cell adhesion, mineralization and cellular attachment in the experimental group A compared with the control group. The animal study revealed an increased number of osteoclasts, newly formed and mature bones in the experimental group A compared with the control group. Eventually, a higher number of osteoclasts were observed in the experimental group B. However, the emergence of newly formed and mature bone was lower than in the experimental group A. The current results suggest that treatment with demineralized and particulate autogenous tooth and interleukin-6 is not effective in stimulating bone regeneration during the bone grafting procedure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제42권2호
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• pp.90-98
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• 2016

Objectives: The aim of this study was to compare the osteogenic effects of demineralized dentin matrix (DDM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in rabbit calvarial defects with DDM and anorganic bovine bone (ABB) combined with rhBMP-2. Materials and Methods: Four round defects with 8-mm diameters were created in each rabbit calvaria. Each defect was treated with one of the following: 1) DDM, 2) ABB/rhBMP-2, or 3) DDM/rhBMP-2. The rhBMP-2 was combined with DDM and ABB according to a stepwise dry and dip lyophilizing protocol. Histological and microcomputed tomography (${\mu}CT$) analyses were performed to measure the amount of bone formation and bone volume after 2- and 8-week healing intervals. Results: Upon histological observation at two weeks, the DDM and ABB/rhBMP-2 groups showed osteoconductive bone formation, while the DDM/rhBMP-2 group showed osteoconductive and osteoinductive bone formation. New bone formation was higher in DDM/rhBMP-2, DDM and ABB decreasing order. The amounts of bone formation were very similar at two weeks; however, at eight weeks, the DDM/rhBMP-2 group showed a twofold greater amount of bone formation compared to the DDM and ABB/rhBMP-2 groups. The ${\mu}CT$ analysis showed markedly increased bone volume in the DDM/rhBMP-2 group at eight weeks compared with that of the DDM group. Notably, there was a slight decrease in bone volume in the ABB/rhBMP-2 group at eight weeks. There were no significant differences among the DDM, ABB/rhBMP-2, and DDM/rhBMP-2 groups at two or eight weeks. Conclusion: Within the limitations of this study, DDM appears to be a suitable carrier for rhBMP-2 in orthotopic sites.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.468-476
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• 1998

The purpose of this study was to observe the morphologic change of dentinal surface, adhesion in interface between dentin and bonding agents, and penetration pattern of resin tags into dentinal tubles according to bonding procedure of ONE-STEP universal adhesive system. Ten extracted human molars were mounted in dental stone and sectioned to expose mid-coronal occlusal dentin and again sectioned tooth crown apically. Specimens were randomly assigned to three groups for dentin conditioning with 32% phoshoric acid, two coats of bonding agents after dentin conditioning, and bond of composite resin. The surfaces of dentin were treated with etch ant and applied bonding agent, and bonded composite resin according to the directions of manufacturer. Specimens which were boned composite were sectioned longitudinally for observing interfaces between resin and dentin. Two of specimens which were sectioned longitudinally were immersed in 6 N HCL for 30 seconds and 1% NaOCL for 12 hours to partially demineralize and deproteinize the dentin substrate. Each specimen was mounted on a brass stub, sputter-coated with gold and observed under SEM. The result were as follows : 1. On the dentinal surface which was conditioned with 32% phosphoric acid. the smear layer was completely removed. orifices of dentinal tubules were opened 3-$5{\mu}m$ wide. and dentinal surface was irregular. 2. On the dentinal surface which was applied ONE-STEP. bonding agent. resin particles were observed on the orifices of dentinal tubules and intertubular dentin. 3. There were close adaptation between dentin and resin and were the pattern which composite invaded into dentin. 4. 1-$3{\mu}m$-wide hybrid layer was visible in the interface between dentin and resin. 5. Long and funnel shaped resin tags were observed in demineralized specimens. and the surfaces of tags were rough.

• Restorative Dentistry and Endodontics
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• 제18권1호
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• pp.38-53
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• 1993

The purpose of this study was to observe the resin infiltration pattern into dentin by various dentin bonding agents. Freshley extracted 36 sound human molars were used in this study. They were stored at $4^{\circ}C$ physiologic saline solution before experiment. All the teeth were cross-sectioned to expose dentin below about 3.0mm at the cusp tip and above 2.0mm at the cemento-enamel junction with Crystal Cutter (MC411 D, Maruto Co., Japan), and were made into specimens for this study (Fig. 1). The specimen experimental groups were divided into 9 groups by dentin surface treatment as following procedures: Group I: Treated with Gluma Cleanser followed by Gluma Primer and Sealer Group 2. Treated with Gluma Cleanser followed by Scotch bond 2 Adhesive Group 3: Treated with Gluma Cleanser followed by Tenure Solution A, Band Visar Seal Group 4: Treated with Scotchprep followed by Scotch bond 2 Adhesive Group 5: Treated with Scotchprep followed by Gluma Primer and Sealer Group 6: Treated with Scotch prep followed by Tenure Solution A, Band Visar Seal Group 7: Treated with Tenure Conditioner followed by Tenure Solution A, Band Visar Seal Group 8: Treated with Tenure Conditioner followed by Scotchbond 2 Adhesive Group 9: Treated with Tenure Conditioner followed by Gluma Primer and Sealer 27 specimens of 36 specimens were divided into 9 groups (Group 1-9), and were used for observation of resin tags. Remaining 9 specimens were divided into 3 groups (Group 1,4 and 7), and were used for observation of fractured dentin surfaces. Specimens to observe the resin tag were demineralized with 20% HCl for 14 hours, specimens to observe the fractured dentin surfaces were demineralized with 10% HCl for 3 minutes. All the specimens were gold-coated with Eiko ion coater (Eiko-engineering Co.), and observed under Scanning electron microscope (Hitachi S-2300) at 20 KV. The following results were obtained: 1. In group 1 treated with Gluma Cleanser, Gluma Primer, and Sealer, most resin tags were more than $100{\mu}m$. 2. In group 4 treated with Scotch prep and Scotchbond 2 Adhesive, most resin tags were about $10{\mu}m$. 3. In group 7 treated with Tenure conditioner, Tenure Solution A, B, and Visar Seal, most resin tags were about $10{\mu}m$ but occasionally resin tags were more than $100{\mu}m$. 4. In groups 2,3,5,6,8 and 9, the lengths of resin tags were inconsistent and the amount of resin tags were reduced.

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.201-216
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• 1990

A variety of surface pre-treatments have been advocated to prepare the dentin prior to placement of a bonding agent. The purpose of this study was to evaluate the effect of various dentin conditioners upon the degree of resin impregnation to the dentinal tubules and the shear bond strength of a new dentinal bonding agent (Scotchbond 2) used in conjunction with a visible light cured composite (Silux). The healthy eighty human molars extracted due to periodontal or orthodontic reasons were used and randomly divided into five groups. All the grinded dentin surfaces were conditioned with 3% $H_2O_2$, Cavity Cleanser (Columbus/Bayer), Dentin Conditioner (GC Inter. Corp.), Scotchprep (3M Co.) according to the manufacturer's directions. The specimens were then demineralized in 10% HCl for 20 sec. and 24 hrs. in order to observe the resin tags in Hitachi X-450 scanning electron microscope at 25KV. Also, shear strengths were obtained using an Instron Testing Machine with a cross head speed of 1 mm/min. The following results were obtained ; 1. In group treating with Dentin Conditioner and Scotchprep, the resin strings were formed on most of the surfaces and penetrated more than $50{\mu}m$ into the tubules. 2. The inner surface of resin treated with Cavity Cleanser, indicating the resin strings formed partly and penetrated about in depth of $30{\mu}m$. 3. In control and experimental group treated with 3% $H_2O_2$, the resin tags were not formed, if any, penetrated shortly. 4. Shear bond strengths in groups treating with Dentin Conditioner and Scotchprep were statistically significant increase than with 3% $H_2O_2$. (P<0.01). 5. The Scotchprep treatment group was significantly higher in shear strength than groups treated with no conditioning and Cavity Cleanser.(P<0.01) 6. Shear bond strengths evaluated were gradually increase in proportion to the tag length of resin impregnation.

• Restorative Dentistry and Endodontics
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• 제20권2호
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• pp.463-486
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• 1995

The effect of moistening and air-drying of acid-conditioned dentin before priming on the formation of resin-dentin hybrid zone was investigated, Freshly extracted human molars were used and divided at random into 5 groups, Groups 1 - 3 consisted of specimens conditioned with 10 % phosphoric acid for 20 seconds; Group 1 served as a control in which the conditioned dentin was simply blot-dried with a damp facial tissue; Group 2 was air dried for 30 seconds ; Group 3 was air dried for 30 seconds and immediately remoistened for 10 seconds with air-water syringe. and then the specimen was blot-dried with a damp facial tissue. Groups 4-5 were not acid conditioned ; In group 4, the smear layer on the dentin was blot dried before primer placement; Group 5 was air dried only for 30 seconds, The acetone-based primer and bonding agent of All Bond 2 (Bisco. Inc., USA) and composite resin (Z-100, 3M Dental products, USA) were applied for acid conditioned dentin and non-conditioned dentin. The morphologic ultrastructure of resin-dentin hybrid zone was examined by the use of SEM and TEM. and the existence of inorganic material and analysis of Ca/P weight-percent ratio in the resin-dentin hybrid zone were revealed by the EDAX, The results were as follows : 1. In the moistened specimens from acid-conditioned groups, the resin penetrated about 3-$4{\mu}m$ into dentin and the denatured collagen smear layer was not present at the surface. The resin tag was formed to a thickeness of 3-$4{\mu}m$ at the upper part of dentinal tubule and compactively connected to each other by means of many lateral branching. 2. In the air-dried specimens from acid-conditioned groups, the resin penetrated about 2.0-$2.5\;{\mu}m$ into dentin and an upper thin black layer to a thickness of 30-35nm was identified between adhesive resin and demineralized collagen layer. The resin tag to have a diameter of $2.5{\mu}m$ was formed at the upper part of dentinal tubule. However the funnel shape of the tag was not notable compared to the moistened specimens. 3. In the remoistened specimens from acid conditioned groups, the resin penetrated about 2.0-$2.5{\mu}m$ into dentin and an upper black layer was not present. The resin tag at the upper part of dentinal tubule was formed less than $2{\mu}m$ and was weakly connected to each other by means of few lateral branching. 4. In the non-conditioned groups, the smear layer was formed to a thickness of $0.5{\mu}m$ at dentin surface. However, the resin-dentin hybrid zone was not identified by TEM. The evidence of resin penetration into intertubular and intratubular dentin did not show. 5. All the acid-conditioned groups showed that the detected calcium and phosphorus weight percent ratios at the $2{\mu}m$ upper portion from the resin-dentin interface into the resin were much higher than that at the $2{\mu}m$ lower portion from the resin-dentin interface to dentin. (P<0.01).

• Restorative Dentistry and Endodontics
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• 제13권2호
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• pp.323-334
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• 1988

The purpose of this study was to observe the effect of dentin surface conditioners on the dentin surfaces. Freshly extracted human molars were used in this study. They were stored at $4^{\circ}C$ saline solution before experiment. The crown portions of the teeth were cut in various directions by means of wet diamond point to expose dentin which include transverse, vertical oblique, horizontal and oblique cut to the long axis (Fig. 1). Each tooth was then mounted with self curing acrylic resin in brass ring to expose the flattened dentin surfaces. Final finish was accomplished by grinding the dentin specimens with wet No. 180 and No. 600 grit silicon carbide abrasive paper until a 6.0mm in diameter on a dentin surface was exposed without pulp exposure. The specimens were divided into 9 groups according to the modes of dentin treatment procedure. The following surface treatments were applied on these preparation surfaces; Group 1: unetched (control group) after finish with No. 600 silicon carbide abrasive paper. Group 2: etched with 30% phosphoric acid for 60s Group 3: etched with 10-3 solution for 60s Group 4: Cleaned with 5% NaOCl for 30s Group 5: applied Dentin Adhesit Group 6: cleaned with 5% NaOCl followed by applying the Dentin Adhesit$^{(R)}$ Group 7: applied Photo Bond on the unetched dentin followed by applying the Photo Clearfil Bright Group 8: Etched with 30% phosphoric acid followed by applying Photo Bond and Photo Clearfil Bright Group 9: etched with 10-3 solution followed by applying Photo Bond and Photo Clearfil Bright All the specimens were stored in $37^{\circ}C$ under 50% relative humidity for 24 hours before observations. The specimens in 7, 8, and 9 group, omitting the group 1 to 6, were demineralized in 10% HCl for 10s in order to observe the resin tags. All the specimens in each group were then dried at room temperature. The dried specimens were ion coated with Eiko ion coater (Eiko-engineering Co.), and observed in Hitachi S-430 Scanning electron microscope (Hitachi, Co. Tokyo) at 15KV. The following results were obtained as follows; 1. The smear layers were still remained in group 1,2,4,5, and 6. 2. There is no effect of 5% NaOCl and 30% phosphoric acid on the changes of dentin morphology 3. The dentin treated with 10-3 solution, indicating the tubules opened when the smear layer and the dental plug dissolved. 4. In case of applying the bonding agents the resin tag was not formed at the deep area of dentinal tubules, but in case of applying the Dentin Adhesit$^{(R)}$ that was not.

• 대한치과의사협회지
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• 제50권9호
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• pp.574-585
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• 2012

Purpose : This study was performed to evaluate the healing response around the root perforation restorative material. Materials and Methods : Four beagle dogs were used for experimental study. Endodontic treatment was performed at four maxillary premolars and artificial perforation was formed at furcation area of pulp chamber. Canal was filled with gutta percha cone and the perforation was sealed with MTA at group 1. At group 2, canal was filled and the perforation was sealed with dentin paste. Tooth paste was fabricated using extracted human teeth. Histologic examination of furcation area was performed 2, 4, 8 and 12 weeks after experiment. Results : New trabecular bone formation was observed around the MTA and tooth paste. Lamellar bone was observed as time is over. There were no inflammatory reaction in both groups. Conclusion : There is a possibility which endodontic filling material can be developed using extracted teeth.