• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.2
• /
• pp.255-261
• /
• 2002

The purpose of this study was to compare the microleakage pattern of flowable composite resin to sealant, composite resin used in preventive resin restoration and glass ionomer cement used as liner. 120 extracted sound human molars were divided into 6 groups : group 1 and 2:sealant ; group 3 and 4:preventive resin restoration ; group 5 and 6:sandwich technique restoration. For the experimental groups(group 2, 4 and 6), flowable composite resin(Tetric flow) was used. For the control group, Concise was used as sealant material(group 1), Z-100 with Concise were used as preventive resin restoration(group 3), and Vitrebond was used as cavity liner(group 5). All the restorations were thermocycled and the degree of dye penetration was evaluated with stereomicroscope. The microleakage of each group was measured and statistically analyzed. The results of the present study were as follows : 1. In group 1 and 2, there was no statistically significant difference in microleakage between Concise and Tetric flow(p>0.05). 2. In groups of preventive resin restorations, there was no statistically significant difference in microleakage between Z-100 with Concise and Tetric flow(p>0.05). 3. The microleakage of Vitrebond and Tetric flow used as liner showed no statistically significant difference(p>0.05).

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

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.558.2-558
• /
• 2001

The aims of this study are (1) to investigate the relation of irradiation mode, polymerization shrinkage and degree of cure of composite resin and(2) it effect on micorleakage of class V restorations. VIP(BISCO Dental Products, Schaumburg, IL, USA) and Optilux 501 (Demetron/Kerr, Danbury, CT, USA) curing lights were used for curing Z-250 composite resin following irradiation mode: VIP 200㎽d, VIP 400㎽, VIP 600㎽, pulse-delay(200㎽ 3sec, 5min wait, 600㎽ 30sec), Optilux R mode.(omitted)

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.555-555
• /
• 2001

The aims of this study are (1) to investigate the relation of irradiation mode, polymerzition shrinkage and degree of cure of composite resin and (2) it effect on microliakage of calss V restorations. VIP(BISCO Dental Products, Schaumburg, IL, USA) and Optilux 501(Demetron/Kerr, Danbury, CT, USA) curing lights were used for curing Z-250 composite resin following irradiation mode: VIP 200㎽, VIP 400㎽, VIP 600㎽, pulse-delay(200㎽ 3sec, 5min wait, 600㎽ 30sec), Optilux C mode, Optilux R mode.(omitted)

• Restorative Dentistry and Endodontics
• /
• v.30 no.5
• /
• pp.355-362
• /
• 2005

The purpose of this study was to compare the effect on marginal leakage of a resin surface sealant (Biscover) applied before or after polymerization of composite resin to unsealed composite restorations. Thirty Class V cavities with the occlusal margin in enamel and cervical margin in dentin or cementum were prepared on the buccal surfaces of sound extracted molars and restored with a microfilled light-cured composite resin (Micronew). Restorations were randomly assigned into one of three equal groups (n = 10): a control group - no surface sealing, group 1 - applied Biscover after polymerization of the composite resin. and group 2 - applied Biscover before polymerization of the composite resin. Specimens were thermocycled, immersed in a $20\%$ methylene blue solution for 4 hoots, sectioned longitudinally, and analyzed for leakage at the occlusal and gingival margins. The results of this study were as follows 1. In sealed group, group 2 showed higher microleakage than group 1 at both occlusal and gingival margins. but there was no significant difference between two groups (p > 0.05). 2. Unsealed control group showed a little higher microleakage than sealed group at occlusal margins, and a little Higher or similar microleakage than sealed group at gingival margins (p > 0.05) 3. Control group and group 2 showed significantly less microleakage at the occlusal margins, but group 1 showed no significantly difference between microleakage at the occlusal and gingival margins.

• Restorative Dentistry and Endodontics
• /
• v.26 no.2
• /
• pp.180-187
• /
• 2001

The structure of current guides is largely illogical and without any rational use of color ordering. The shade guides are generally made of plastic (rather than the actual composite material) and do not accurately depict the true shade. translucency. or opacity of the composite resin after polymerization. To solve this problem, information based on evaluations of natural teeth and material that use the same method and experimental conditions is necessary. The present investigation measured the color of natural maxillary anterior teeth in vivo and compared the results with those of composite resins. 269 Korean subjects were selected for this study. Intact central incisor. lateral incisor. and canine were selected. The clinical crowns were free of caries or restorations. The middle site of the coronal portion on the labial surface of the tooth was measured by Chroma Meter. The five light activated. resin-based materials (Amelogen, Denfil, Elitefil, Spectrum, Z100) were used in this study. Resin composite was condensed into plastic mold with a diameter of 8mm and a thickness of 4mm. pressed between glass plates to flatten the surfaces. and polymerized using a Visilux II visible light activation unit. The surfaces were polished sequentially on wet sandpaper. Color measurements of each specimen were accomplished by Chroma Meter. A computer program that compares each tooth color with each composite resin color was written and the minimum CIELAB color difference ($\Delta$E$^*$) between tooth and each material was calculated. Under the conditions of this study: 1. Teeth tend to become darker with advancing age. 2. Canines were darker. more yellow. and less green than incisors. 3. The teeth from the women were lighter. more green. and less yellow than the male teeth. 4. In general. composite resins were lighter. more green. and less yellow than teeth. Deficiencies were noted in Hues in YR range. 5. Mean color differences between the five composite resin products and teeth were detectable to the naked eye($\Delta$E$^*$>1.0). 6. In comparing the mean $\Delta$E$^*$ values of materials. Spectrum showed the least followed by Z100, Elitefil, Amelogen, Denfil in increasing order.

• Restorative Dentistry and Endodontics
• /
• v.25 no.3
• /
• pp.313-320
• /
• 2000

The purpose of this study was to evaluate on the interfacial morphology between dentin and restorative materials. In this in vitro study, the cavity wall restorated with 3 different kinds of tooth colored restorative materials [resin-modified Glass Ionomer cement (Fuji II LC), composite resin (Z-100), compomer (Dyract)]. The thirty extracted human molar teeth without caries and/or restorations are used. The experimental teeth were randomly divided into three groups of ten teeth each. In each group, Wedge shaped cavities (width: 3mm, length: 2mm, depth: 1.5mm) were prepared at the cementoenamel junction on buccal and lingual surfaces. The adhesive of composite resin were mixed with rhodamine B. Primer of composite resin, Prime & Bond 2.1 of Dyract and liquid of Fuji II LC were mixed with fluorescein. In group 1, the cavity wall was treatment with dentin conditioner, and then restorated with Fuji II LC. In group 2, the cavity wall was treatment with Prime & Bond 2.1 and then restorated with Dyract. In group 3, the cavity wall was etching with 10% maleic acid, applied with primer and bonding agent and then restorated with Z-100. The interface between dentin and restorative materials was observed by fluoresence imaging with a confocal laser scanning microscope. The results were as follows : 1. In Glass ionomer group, adaptation of resin modified Glass-ionomer restoration against cavity wall is tight, but the crack formed inside of restoration were observed. 2. In Dyract group, the penetration of resin tag is shorter and the width of hybrid layer is narrower than composite resin group. 3. In Z-100 group, primer penetrated deeply through dentinal tubule. Also bonding agent was penetrated along the primer, but the penetration length is shorter than primer part, and in 3-D image, the resin tag is conical shape and lateral branch is observed.

• Restorative Dentistry and Endodontics
• /
• v.43 no.2
• /
• pp.22.1-22.9
• /
• 2018

Objectives: To evaluate and compare light-transmittance in dental tissues and dental composite restorations using the incremental double-layer technique with varying layer thickness. Materials and Methods: B1-colored natural teeth slabs were compared to dental restoration build-ups with A2D and B1E-colored nanofilled, supra-nanofilled, microfilled, and microhybrid composites. The enamel layer varied from 0.3, 0.5, or 1.2 mm thick, and the dentin layer was varied to provide a standardized 3.7 mm overall sample thickness (n = 10). All increments were light-cured to $16J/cm^2$ with a multi-wave LED (Valo, Ultradent). Using a spectrophotometer, the samples were irradiated by an RGB laser beam. A voltmeter recorded the light output signal to calculate the light-transmittance through the specimens. The data were analyzed using 1-way analysis of variance followed by the post hoc Tukey's test (p = 0.05). Results: Mean light-transmittance observed at thicker final layers of enamel were significantly lower than those observed at thinner final layers. Within 1.2 mm final enamel resin layer (FERL) thickness, all composites were similar to the dental tissues, with exception of the nanofilled composite. However, within 0.5 mm FERL thickness, only the suprananofilled composite showed no difference from the dental tissues. Within 0.3 mm FERL thickness, none of the composites were similar to the dental tissues. Conclusions: The supra-nanofilled composite had the most similar light-transmittance pattern when compared to the natural teeth. However, for other composites, thicker FERL have a greater chance to match the light-transmittance of natural dental tissues.

• Restorative Dentistry and Endodontics
• /
• v.17 no.1
• /
• pp.191-205
• /
• 1992

The purpose of this study was to evaluate the microleakage of class II composite resin inlays and compare them with the conventional light-cured resin filling restorations. Class II cavities were prepared in 60 extracted human molars with which cervical margins were located below 1.0mm at the cemento-enamel junction using No. 701 tapered fissure carbide bur. All of the prepared cavities were restored as follows and divided into 6 groups. Group I and 2 were restored using direct filling technique and group 3,4,5 and 6 were restored using direct inlay technique that was cemented with dual-cured resin cements. group I: Cavities were restored with light-curing composite resin, Brilliant Lux. group 2. Cavities were restored with light-curing composite resin, Clearfil PhotoPosterior. group 3: Cavities were restored with Clearfil CR Inlay and heat treated at $125^{\circ}C$ for 7 minutes. group 4: Cavities were restored with same material as group 3 and heat treated at $100^{\circ}C$ for 15 minutes. group 5: Cavities were restored with Brilliant (Indirect esthetic system) and heat treated at $125^{\circ}C$ for 7 minutes. group 6: Cavities were restored with same material as group 5 and heat treated at $100^{\circ}C$ for 15 minutes. All specimens were polished with same method and thermocycled between $6^{\circ}C$ and $60^{\circ}C$, then immersed in a bath of 2.0% aqueous solution of basic fuchsin dye for 24 hours. Dyed specimens were sectioned longitudinally and dye penetration degree was read on a scale of 0 to 4 by Tani and Buonocore's method 45). The results were as follows: 1. Microleakage was observed rather at the cervical margins than at the occlusal margins in all groups. 2. Composite resin inlay groups showed significantly less leakage than direct filling groups at the cervical margins (p < 0.001). 3. In composite resin inlay groups, there was no significant difference in microleakage between specimens by heat treating temperature and time (p > 0.05). 4. There was no significant difference in leakage between each groups at the occlusal margins (p > 0.05).

• Restorative Dentistry and Endodontics
• /
• v.35 no.2
• /
• pp.116-124
• /
• 2010

This study aimed to assess whether the gender of the dental practitioner affects operative techniques in class 2 and class 5 resin composite restorations. In 2008, a nationwide survey was given to Korean dentists. Total 12,193 e-mails were distributed, 2,632 were opened by recipients, and 840 responses were collected. Of the respondents, 78.9% were male and 21.1% were female. The gender distribution in the age groups between respondents and the total population did not differ (p > 0.05). A chi-square test was used to compare technical differences between female and male dentists. A multiple logistic regression analysis was performed to assess the association between gender and operative techniques in resin composite restoration. For class 2 resin composite restoration, female dentists were 1.87 times more likely than male dentists to do multiple incremental fillings (four layers or more) and 2.72 times more likely than males to spend 30 minutes or more for the treatment (p < 0.05). For class 5 resin composite restoration, female dentists were 2.69 times more likely than their male counterparts to use a cavity base or liner, 1.83 times more likely to do multiple incremental fillings (four layers or more) and 1.63 times more likely to spend 20 minutes or more for the procedure (p < 0.05). The gender factor was influential to individual operative techniques in restorative treatment.