• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.2
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• pp.277-284
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• 1998

For the purpose of comparing the shear bond strengths of pit and fissure sealants, and finding out the more efficient method of tooth surface treatment when the etched surface is contaminaed by saliva or moisture, an experiment was performed on 3 types of pit and fissure sealants. 120 extracted human molars were divided into 3 groups, each of which was composed of 40 specimens sealed with Helioseal, Teethmate-F and Fuji III respectively. And each groups was again divided into 4 subgroups according to tooth surface treatment. The shear bond strengths of each groups and subgroup was measured and statistically analyzed. The results obtained were as follows : 1. Shear bond strengths of nonfluoridated resin sealant, Helioseal were shown to be higher than those of fluoridated resin sealant, Teethmate-F, but, not significantly different. 2. Shear bond strengths of GI sealant, Fuji III were to be markedly lower than those of two resin sealants. 3. When there is moisture contamination, applying primer under sealant(Group IV) results in a significantly stronger bond strength of sealant to enamel than when using sealant alone(Group II) in case of all sealants. 4. When there is no moisture contamination, using primer under sealant (Group III) results in bond strength equivalent to bond strength on using sealant alone (Group I). 5. Based on the results above, it was demonstrated that the bond of sealant to tooth surface is greatly affected by saliva contamination and that the complete tooth isolation method should be fully emphasized. The application of primer is recommended when performing sealant under the environment very susceptible to saliva contamination.

• The korean journal of orthodontics
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• v.31 no.4 s.87
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• pp.459-465
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• 2001

The purpose of this study was to evaluate the feasibility of the combined use of paste resin with sealant as an adhesive of the indirect bonding. The resin bases made of light-cured resin were bonded to the bovine incisors at a distance of 0.0, 0.2 or 0.4 mm using the sealant only or the mixture of sealant and paste resin. Bond strength of each group was measured using universal testing machine. The results were as follows : 1. The bond strength was reduced in both groups as the distance between enamel surface and resin base increased. 2. The bond strength showed no statistical difference between two groups in case the distance between enamel surface and resin base was 0.0 mm. 3. In case the distance between enamel surface and resin base was 0.2 or 0.4 mm, the sealant with paste resin group showed significantly higher bond strength than the sealant only group. The results of the present study indicate that the use of paste resin with sealant may be desirable as an adhesive in indirect bonding, particularly in case a gap is suspected between enamel surface and resin base.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.138-150
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• 2007

The purpose of this study was to evaluate the difference of surface roughness of composite resin according to composite resin type, polishing methods, and use of resin sealant. Two hundred rectangular specimens, sized $8{\times}3{\times}2mm$, were made of Micro-new (Bisco, Inc., Schaumburg, IL, U.S.A) and Filtek Supreme (3M ESPE Dental Products, St. Paul, MN, U.S.A.), and divided into two groups; Micronew-M group, Filtek Supreme-S group. Specimens for each composite group were subdivided into five groups by finishing and polishing instruments used; M1 & S1(polyester strip), M2 & S2 (Sof-Lex disc), M3 & S3 (Enhance disc and polishing paste), M4 & S4(Astropol) and M5 & S5 (finishing bur), Polished groups were added letter B after the application of resin surface sealant (Biscover), eg, M1B and S1B. After specimens were stored with distilled water for 24hr, average surface roughness (Ra) was taken using a surface roughness tester. Representative specimens of each group were examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using paired t-test, ANOVA and Duncan's tests at the 0.05 probability level. The results of this study were as follows ; 1. The lowest Ra was achieved in all groups using polyester strip and the highest Ra was achieved in M5, S5 and M5B groups using finishing bur. On FE-SEM, M1 and S1 groups provided the smoothest surfaces, M5 and S5 groups were presented the roughest surfaces and voids by debonding of filler on the polished specimens. 2. There was no significant difference in Ra between Micronew and Filtek Supreme before the application of resin sealant, but Micronew was smoother than Filek Supreme after the application of resin sealant. 3. There was significant corelation between Ra of type of composite resin and polishing methods before the application of resin sealant (p=0.000), but no significant interaction between them after the application of resin sealant. On FE-SEM, most of composite resin surfaces were smooth after the application of resin sealant on the polished specimens. 4. Compared with before and after the application of resin sealant in group treated in the same composite and polishing methods, Ra of M4B and M5B was statistically lower than that of M4 and M5, and S5B was lower than that of S5, respectively (p<0.05). In conclusion, surface roughness by polishing instruments was different according to type of composite resin. Overall, polyester strip produced the smoothest surface, but finishing bur produced the roughest surface. Application of resin sealant provided the smooth surfaces in specimens polished with Enhance, Astropol and finishing bur, but not provided them in specimens polished with Sof-Lex disc.

• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.64-76
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• 2001

Despite the improvements in bond strengths of dentin adhesives and resin-modified glass ionomers, the marginal seal of cervical restorations remains a concern. Microleakage at poorly sealed margins can result in staining, post-operative sensitivity, pulpal irritation, and recurrent caries. The objective of this study was to evaluate the effect of surface penetrating sealant(SPS) on the microleakage of cervical restorations. 45 extracted human teeth were selected, and Class V preparations were prepared on the both buccal and lingual surface of the teeth to the following dimensions : 1.5mm axially, 3mm mesiodistally, and 3mm incisogingivally. After cervical restoration with composite resin, compomer, glass ionomer each restoration was treated as three methods: No Tx., Scotchbond Multipurpose Adhesive$^{\circledR}$, Fortify$^{\circledR}$. The sections were examined with a stereomicroscope to determine the extent of microleakage at enamel and dentin margins. The results of this study were as follows. 1. All groups showed some microleakage. 2. Gingival cavity wall with cementum margin showed significantly higher leakage value than occlusal cavity wall with enamel margin. 3. The group treated with SPS showed significantly lower leakage value than no treated group(p<0.05). But there is no difference between Fortify$^{\circledR}$ and Scotchbond Multipurpose adhesive$^{\circledR}$. The results of this study suggest that SPS are effective in reducing microleakage of class V restorations. But it is certain that some microleakage still occurred despite the application of SPS.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.437-441
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• 2017

This study was carried out to investigate the volumetric expansion ratio and hardness of expanded graphite after coating with various resins which were used as an additive of fireproof sealant. The coating thickness of the resin, which represents the coating rate, was dependent of the drying speed of the resin and the viscosity of the resin. Therefore the coating thickness was shown as follows: polyvinyl acetate > acrylic resin > urethane resin > water soluble latex. Furthermore, the volumetric expansion ratio was as follows: urethane resin > water soluble latex > acrylic resin > polyinyl acetate and the hardness was as follows: polyvinyl acetate resin > acrylic resin > water soluble latex > urethane resin. This showed that the volume of expansion was reduced by expansion, which was not covered by coating, but significantly increased by increasing hardness and allowed it to be used as a refractory addition. According to the response surface methodology, the optimized addition amount and stirring speed of acrylic resin were 37.6 wt% and 441.4 rpm, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.460-474
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• 1997

The purpose of this study was to evaluate and compare the effectiveness of various low-viscosity resin systems used as rebonding agents to prevent microleakage at the margins of class I composite resin restorations. Seventy sound human premolars were selected for experiment. Class I cavities were prepared and each cavity was conditioned with a 37% phosphoric acid for 15 sec, rinsed with water for 15 sec, and dried with compressed air. Bonding agent(Scotchbond Multipurpose, 3M Co.) was applied and a hybrid composite resin (Z-100, 3M Co.) was placed using an incremental technic. The excess cured composite resin was carefully removed with Sof-Lex discs(3M Co.) to expose the original margins of the cavity. The following seven groups were established : group 1 was not rebonded and used as control group ; group 2 was rebonded with a Scotchbond Multipurpose(3M Co.) and finished ; group 3 was rebonded with a Fortify(BISCO) and finished ; group 4 was rebonded with a Concise white sealant(3M Co.) and finished ; group 5 was rebonded with a Concise white sealant(3M Co.) and not finished ; group 6 was rebonded with a P&F sealant(BISCO) and finished; group 7 was rebonded with a P&F sealant(BISCO) and not finished. The specimens were then subjected to 500 thermocycles between 5 & 65 with a 10 see dwell time and immersed in 2% methylene blue dye solution for 24 hours and sectioned with low-speed diamond cutter into two part under water condition. The extent of microleakage at rebonded margins was evaluated microscopically and scored for dye penetration according to the following scale : 0=no dye penetration ; 1=dye penetration to half-way along axial wall between enamel surface and DEJ ; 2=dye penetration beyond halfway along axial wall between enamel surface and DEJ ; 3=dye penetration to the full depth of DEJ or beyond DEJ. Selected samples were prepared for SEM observation to determine the depth of penetration of the rebonding agent into the marginal interface. The obtained results were as follows: 1. In the group 2 and 3, which is rebonded with a Scotchbond Multipupose and Fortify, dye penetration score were decreased significantly than that of group 1 (P<0.05), but group 4 and 6 were not statistically different from group 1(P>0.05). 2. There were significant differences between group 4, 6 and group 5, 7 when compared by dye penetration score (P<0.05). 3. In the SEM observation, Scotchbond Multipurpose and Fortify were penetrated within $30-40{\mu}m$ depth of the outermost surface. However, both sealants were failed to penetrate into the debonded interface.

• Journal of dental hygiene science
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• v.18 no.6
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• pp.367-373
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• 2018

The consumption of beverages among children is rising. The purpose of this study was to examine the effect of kid's drink on dental resin-based pit and fissure sealant. Pororo, I-kicker, Sunkist kids were included in the experimental groups, and Samdasu was included in the control group. A conventional dental sealant material ($Clinpro^{TM}Sealant^{(R)}$) was selected for this study. Resin specimens (8 mm in diameter and 1 mm in thickness) were prepared according to manufacturers' instructions and the initial roughness (Ra) was then measured. The pH of all the four groups was measured using a pH meter. The specimens were individually immersed in 5 ml of the experimental solutions and stored at $37^{\circ}C$ for 72 hours. Following this, the surface roughness of the resin specimens was measured by Surftest. The concentration of residual monomer released was determined by high performance liquid chromatography (HPLC). The surface morphology of the resin specimen was evaluated before and after storage by scanning electron microscopy (SEM). Data were statistically analyzed using Kruskal-Wallis and Duncan's test. The results showed that all the children's beverages examined in this study contained citric acid. The pH of I-kicker was the lowest ($3.03{\pm}0.01$), followed by that of Sunkist kids ($3.26{\pm}0.02$) and Pororo ($3.47{\pm}0.02$). We observed an increase in the surface roughness of resin specimens after 72 h of immersion in all the beverages tested (p<0.05). There was matrix degradation after immersion, visualized on SEM image, in all the beverage groups. Bisphenol-A-glycidyl methacrylate was not detected after 72 hours, but triethylene glycol dimethacrylate levels were increased in all the beverages tested during the 72 hours by HPLC. These results suggest that intake of beverages containing acid can cause degradation of the resin-based pit and fissure sealants in children.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.247-252
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• 2013

Pit and fissure sealant prevents biofilm accumulation, plays a role in forming a barrier to acidic substance made by the bacteria. The Surface reaction-type pre-reacted glass ionomerI(S-PRG) filler was developed in 1999. S-PRG filler releases fluoride continuously and does not decompose under wet conditions. The aim of this study was to test the microleakage and anticariogenic effect to adjacent enamel of S-PRG filler-containing pit and fissure sealant. Sound premolars and molars were used in this study. A S-PRG filler-containing pit and fissure sealant, Beautisealant$^{(R)}$(Shofu, Japan) was used for this experiment, the composite resin sealant Concise$^{(R)}$(3M ESPE, USA) was used as control. For the microleakage test, all teeth surface were double coated with finger nail varnish, with the exception of a 1.0 mm window around the restoration margins. The teeth were immersed in 2% methylene blue solution for 24 hours and then rinsed in tap water. For the anticariogenic effect evaluation, all tooth were immersed in artificial carious solution for 9 days and rinsed with tap water. Each tooth was embedded in orthodontic acrylic rein and subsequently sectioned longitudinally in a bucco-lingual direction with a low-speed diamond saw. The cut sections were examined using a stereomicroscope. Differences in microleakage between the two groups were not different significantly. But the S-PRG filler-containing pit and fissure sealant showed higher anticariogenic effect than that of flowable resin sealant.

• Restorative Dentistry and Endodontics
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• v.45 no.1
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• pp.12.1-12.8
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• 2020

Objectives: The aim of this in vitro study was to evaluate the microhardness and surface roughness of composite resins before and after tooth bleaching procedures. Materials and Methods: Sixty specimens were prepared of each composite resin (Filtek Supreme XT and Opallis), and BisCover LV surface sealant was applied to half of the specimens. Thirty enamel samples were obtained from the buccal and lingual surfaces of human molars for use as the control group. The surface roughness and microhardness were measured before and after bleaching procedures with 35% hydrogen peroxide or 16% carbamide (n = 10). Data were analyzed using 1-way analysis of variance and the Fisher test (α = 0.05). Results: Neither hydrogen peroxide nor carbamide peroxide treatment significantly altered the hardness of the composite resins, regardless of surface sealant application; however, both treatments significantly decreased the hardness of the tooth samples (p < 0.05). The bleaching did not cause any change in surface roughness, with the exception of the unsealed Opallis composite resin and dental enamel, both of which displayed an increase in surface roughness after bleaching with carbamide peroxide (p < 0.05). Conclusions: The microhardness and surface roughness of enamel and Opallis composite resin were influenced by bleaching procedures.

• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.180-190
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• 2007

The purpose of this study was to evaluate the abrasion resistance of surface penetrating sealant which was applied on a composite resin restoration and to provide proper time to reapply sealant on composite resin surface. Two hundred rectangular specimens, sized $8\times3\times2mm$, were made of Micronew (Bisco, Inc., Schaumburg, IL, U.S.A) and divided into two groups; F group (n = 10) was finished with coarse and medium grit of Sof-Lex discs and BisCoverwas applied B group (n = 190) after finishing with discs. B group was again subdivided into nineteen subgroups From B-1 group to B-18 group were subjected to toothbrush abrasion test using a distilled water-dentifrice slurry and toothbrush heads B-IM group was not subjected to toothbrush abrasion test. Average surface roughness (Ra) of each group was calculated using a surface roughness tester (Surfcorder MSE-1700: Kosaka Laboratory Ltd., Tokyo, Japan) . A representative specimen of each group was examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using cluster analysis, paired t-test, and repeated measure ANOVA. The results of this study were as follows; 1. Ra off group was $0.898{\pm}0.145{\mu}m$ and B-IM group was $0.289{\pm}0.142{\mu}m$. Ra became higher from B-1 group $(0.299{\pm}0.48{\mu}m$ to B-18 group $(0.642{\pm}0.313{\mu}m$. 2. Final cluster center of Ra was $0.361{\mu}m$ in cluster 1 $(B-IM\simB-7)$, $0.511{\mu}m$ in cluster 2 $(B-8\simB-14)$ and $0.624{\mu}m$ in cluster 3 ($(B-15\simB-18)$. There were significant difference among Ra of three clusters. 3 Ra of B-IM group was decreased 210.72% than Ra of F group. Ra of B-8 group and B-15 group was increased 35.49% and 51.35% respectively than Ra of B-IM group. 4. On FE-SEM, B-IM group showed the smoothest resin surface. B-8 group and B-15 group showed vertically shallow scratches , and wide and irregular vertical scratches on composite resin surface respectively. Within a limitation of this study, finished resin surface will be again smooth and glazy if BisCover would be reapplied within 8 to 14 months after applying to resin surface.