• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.95-103
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• 1992

The purpose of this study was to evaluate the effect of the dentin pretreatment on the marginal leakage of a glassionomer cement. 1n this study, 60 molars with sound and healthy crown portion were used. The dentin surface of these teeth were exposed and polished with 600 grit silicon carbide paper. Square - shaped cavities were prepared on the flattened dentin surfaces and these were divided into 4 groups according to the dentin pretreatment procedures. Group I : Dentin pretreatment with distilled water as a control group. Group II : Dentin pretreatment with 5% sodium hypochlorite solution. Group III : Dentin pretreatment with Ketac conditioner. Group IV : Dentin pretreatment with 40% polyacrylic acid. The degrees of dye penetration in the cavity walls were assessed using a stereoscope at ${\times}40$ magnification according to the maximum dye penetration. The results were analyzed by using Mann - Whitney U test. The results were as follows : 1. All groups showed varying depth of dye penetration. 2. Distilled water group showed the most severe marginal leakage when compared with the other groups(P<0.05). 3. 40% polyacrylic acid group showed the least amount of marginal leakage compared with the other groups (P<0.05). 4. There were significant differences between Goup I(distilled water) and Group IV (40% polyacrylic acid)(P<0.05), but there were no significant differences among Group I(distilled water), Group II(sodium hypochlorite), Group III(Ketac conditioner) (P>0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.4
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• pp.647-661
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• 1997

The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The types of fractured patterns were determined with stereoscope(${\times}7.5$). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surfaces and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0. 01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develope better cements.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.101-106
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• 1981

The purpose of this study was to estimate the ability of the marginal fit of Glass ionomer cement. Using the human extracted teeth and 2% acqueous solution of methylene blue, the author investigated the marginal penetration of dye in restorative materials such as Amalgam, Hi-Pol, Glass ionomer cement, Estic microfill and Restodent. The results were as follows. 1. All filling materials showed some degree of marginal penetration. 2. Glass ionomer cement revealed nearly the same microleakage as Estic microfill and Hi-Pol, but showed inferior effect of the marginal seal as compared with Restodent. 3. It is appeared that Amalgam has more effective ability of the marginal fit than the others within a week.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.3
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• pp.184-193
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• 2016

Purpose: To evaluate marginal leakage of bulk fill flowable composite resin filling with different curing time by using microcomputed tomography technology. Materials and Methods: 30 previously extracted human molars were randomly divided into 6 groups based upon restorative system and different curing time. Class II cavities (vertical slot cavities) were prepared. An individual metallic matrix was used to build up the proximal wall. The SonicFill or SureFil SDR flow was inserted into the preparation by using 1 bulk increment, followed by light polymerization for different curing times. The different exposure times were 20, 40, and 60 seconds. All specimens were submitted to 5,000 thermal cycles for artificial aging. Micro-CT scanning was performed by using SkyScan 1272. One evaluator assessed microleakage of silver nitrated solution at the resin-dentin interface. The 3D image of each leakage around the restoration was reconstructed with CT-Analyser V.1.14.4. The leakage was analyzed with the Mann-Whitney test. Results: Significant differences were observed between the light curing times, but no significant differences were found between the bulk fill composite resins. Increasing in the photoactivation time resulted in greater microleakage in all the experimental groups. Those subjected to 60 seconds of light curing showed higher microleakage means than those exposed for 20 seconds and 40 seconds. Conclusion: Increasing the photoactivation time is factor that may increase marginal microlekage of the bulk fill composite resins. Further, micro-CT can nondestructively detect leakage around the resin composite restoration in three dimensions.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.139-150
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• 1988

The purpose of this study was to evaluate the marginal adaptation of Class V resin restorations by the filling techniques. The cavities were filled with Heliosit$^{(R)}$ light curing composite resin system in accordance with the following three filling techniques - bulk-pack placement technique, apical to occlusal layering placement technique, and buccolingual layering placement technique. And the interface between the restoration and the tooth structure was observed with scanning electron microscope. The following results were obtained. 1. Marginal adaptation of enamel showed excellent irrespective of the filling techniques. 2. Marginal leakage of dentin was observed irrespective of the filling techniques. 3. No difference of marginal adaptation according to the filling techniques was observed in light curing composite resin.

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.44-56
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• 1990

This study was designed to assess the degree of the marginal leakage of posterior composite restorations with glass ionomer cement base and Scotchbond$^{(R)}$ by means of the dye penetration at the enamel and dentinal margins. 160 cavities of class V were prepared on the buccal and lingual surfaces of 80 extracted premolar and molar teeth, which were divided into two groups. The buccal cavities of one group were filled with GC lining cement$^{(R)}$, Scotchbond$^{(R)}$ and P 50$^{(R)}$ and the lingual cavities were filled with Scotchbond$^{(R)}$ and Heliomolar$^{(R)}$. The Buccal cavities of other group were filled with Logobond$^{(R)}$, Scotchbond$^{(R)}$ and Heliomolar$^{(R)}$ and lingual cavities were filled with Scotchbond$^{(R)}$ and P 50$^{(R)}$. After finishing, all specimens were subjected manually to 50 thermal cycles at $4^{\circ}C$ and $60^{\circ}C$. They were immersed in 0.5% methylene blue solution for 24 hours and buccolingually sectioned with diamond disc. The sectioned specimens were examined under light microscope. The following results were obtained. 1. The group filled with glass ionomer cement base showed less marginal leakage than the group filled without glass ionomer cement base. 2. The enamel margins showed less microleakage than the dentinal margins in both of the two groups. 3. No significant difference was showed in the microleakage, irrespective of two glass ionomer cement base and posterior composite resin.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.2
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• pp.336-347
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• 2006

Pit and fissure sealants has been proven as safe and effective method of caries prevention. But improper application of pit and fissure sealant may masking the caries process in occlusal fissure. Dentists have to understand the correct and exact application method of pit and fissure sealant for he good result of caries prevention. A key factor to enhanced the effectiveness of caries prevention is retention of pit and fissure sealant. Deep penetration of material into fissure and least marginal leakage around the fissure orifice are the major concerns for dentists to achieve the successive application of pit and fissure sealants. This paper reviewed the literature on the pit and fissure sealants under the following subtitles for enhanced retention : (1) application timing, (2) Indication, (3) Occlusal prophylaxis, (4) Materials, (5) Penetration, (5) Recall check Dental profession must perform the exact application of pit and fissure sealant because this procedure is one of the most technique-sensitive one in dental field.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.4
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• pp.800-817
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• 1996

In this study, we tried to evaluate the effect of Amalgambond liner application on the degree of marginal leakage and retention of amalgam restoration by comparing with that of the Copalite and All-bond 2. The results obtained from this experiment were as follows; 1. Tensile strength representing the bond between amalgam and tooth structure was the highest in Amalgambond, and All-Bond 2, Copalite in descending order. There were statistically significant difference between each group(P<0.05). 2. The degree of microleakage in Amalgambond was lower than that of All-Bond 2, and Copalite, but no stastically significant difference could be found (P>0.05). 3. The liner such as Amalgambond or All-Bond 2 were evaluated to be superior to the conventional Copalite in bond strength as well as in microleakage. But the result of this study could not show the superiority of one material over the others; Amalgambond and All-bond 2. Besides the results of the study, other factors, such as practical convenience, should be considered in determining the selection of material. The support of welldesigned clinical studies on this subject are in demand.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.383-404
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• 1997

In this study, we tried to compare the effect of glass inserts on marginal leakage of composite resin restoration by comparing with that of several filling methods. The results obtained from this experiment were as follows ; 1. The degree of microleakage measured in glass inserts group was generally lower than that of the other groups. Statistical analysis showed significant intergroup difference between glass inserts and one complete unit, pre-polymerized composite resin ball(P<.05), but no significant difference between groups of glass inserts and increments(P>.05). 2. Scanning electron microscopic observation showed relatively large gap around resin-tooth interface in specimens restored the method of using the one complete unit and pre-polymerized composite resin ball whereas a denser and tighter was observed in increments and glass inserts group. Generally the gingival margin was shown to have better bonds than the occlusal margin in specimen of all groups. 3. In the present experiment, methods using the techniques of glass inserts and increments were evaluated to be superior to those of one complete unit, pre-polymerized composite resin ball in the aspect of microleakage. However, the result of this study could not determine the superiority of the use of glass inserts over incremental method. Besides the physical properties observed in this study, the practical aspect of clinical convenience should be considered in determining the selection of material.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.57-68
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• 2002

The purpose of this study was to evaluate microleakage of etched and non-etched amalgam restorations lined with dentin bonding system primer and adhesives. Class V amalgam preparations were made in 100 extracted human premolars divided into 10 groups with 10 teeth each. SEM was taken to assess the dentin/amalgam interface. The results were as follows; 1. At the occlusal and gingival margins, all experimental groups showed lower leakage value than unlined group(p<0.05) The $Copalite^{(R)}-lined$ group showed higher leakage value than other experimental groups(p<0.05). 2. In all experimental groups, the gingival margin showed higher leakage value than the occlusal margin. 3. There were no significant difference between non-etching and etching groups, primer only and primer & adhesive groups, primer & adhesive and self-priming adhesive groups(p>0.05). 4. On the SEM observation, continuous gaps were observed in the unlined and $Copalite^{(R)}-lined$ groups, but the gaps were filled with primer or adhesive layer in other experimental groups.