• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.113-120
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• 1988

The purpose of this study was to evaluate and compare the sealing ability of ZOE, FR and AH-26. Seventy two upper and lower anterior and premolor teeth were randomly selected and instrumented in a conventional method with K-file. After instrumentation and dry the canal, the teeth were divided into 3 groups and twenty four teeth in each group were filled with ZOE, FR, and AH-26 respectively. All the specimens were immersed into Indian Ink and decalcified in nitric acid and cleared in methyl salicylate. The apical leakage was evaluated by measuring the degree of ink penetration with caliper at the intervals of 1 day, 7 days and 14 days. The results were as follows; 1. In AH-26 and FR groups, there was increase in penetration related to increased time of immersion in the ink. 2. FR group showed the least penetration in 3 groups. 3. Statistics showed that there was no significant difference among the each sealer groups.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.131-137
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• 1988

The purpose of this study was to investigate the interfacial bond strength of repaired composite resins, Lite-Fil P and Bis-Fil II, under different interfacial conditions. The matured composite resin specimen were prepared as Table I and divided into 9 groups. All specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before testing. The results were as follows; 1. The bond strength of the groups that bonding agent was applicated was greater than that of the groups that bonding agent was not applicated. 2. The bond strength of the saliva contaminated groups was the lowest. 3. The bond strength of the group that chemical cured composite resin bonded to chemical cured composite resin was greater than that of the other groups. 4. The bond strength of the no-treated group was greater than that of saliva contaminated group, and lesser than that of the bonding agent applicated groups.

• Restorative Dentistry and Endodontics
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• v.12 no.2
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• pp.33-44
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• 1987

The use of composite resin for the posterior teeth gives rise to clinical problem due to the lack of mechanical properties. The purpose of this study was to observe the fractured surfaces of light posterior composite resins which are P-10, Clearfil posterior, Adaptic anterior & posterior, P-30, Lite-fil posterior, Estilux posterior, Helio-molar, and Ful-fil com pules (Table 1). The failure of composite resin specimens of I, T and Y-Type (Fig. 1,2) occured under compression. Fractographical observations by SEM (JSM-T20, JEOL) were carried out in order to examine the fracture behaviour of eight composite resins in different types of specimens. The results obtained from this study were as follows: 1. Similar features were found in fractured surfaces of eight composite resins. 2. The crack growth was initiated at the regions of porosities. 3. The crack propagated on the filler-matrix interface. 4. As the crack increased in size, it accelerated to form secondary crack. 5. The fracture behaviour was dependent on the content, size, shape, and distribution of fillers.

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.569.1-569
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• 2001

The purpose of this investigation was to determine the effect of dipping in tooth reserving solution on bond strength of 4-META/MMA-TBB dentin bonding system. The flattened dentin surface of bovine lower incisor was used for this investigation. The tooth were dipped in the tooth reserving solution (ViaSpan; Du Pont Pharmatical / Teeth Server "NEO";Neo Dental Chemical products CO/LTD, Japan/ Saline, Fuso Chemical CO, LTD, Japan) for 30 min.(omitted)

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.604-604
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• 2003

I. Objectives Newly-designed method was evaluated to measure the linear polymerization shrinkage of light-cured resin composites. II. Materials and Methods A resin composite(Clearfil AP-X, Kuraray, Japan) was filled into a vinyl-polysiloxan mold(1 to 8mm-depth, and 7mm-diameter). As indicators, 4 beads(Retention Beads 2 SS, GC, Japan；particle size $200{\;}\mu\textrm{m}$) were placed diagonally on the resin surface of a mold. The coordinates (x, y, z, pasition) of each indicator were measrued by a measuring-microscope after which the resin surface was irradiated by a curing-light source(Optilux 500, Demetron/Kerr, USA) for 40 sec. After 20 sec the coordinates were again measured.(omitted)

• Restorative Dentistry and Endodontics
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• v.44 no.4
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• pp.45.1-45.10
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• 2019

Objectives: Self-adhesive resin cements contain functional monomers that enable them to adhere to the tooth structure without a separate adhesive or etchant. One of the most stable functional monomers used for chemical bonding to calcium in hydroxyapatite is 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). The aim of this study was to evaluate the influence of the10-MDP concentration on the bond strength and physical properties of self-adhesive resin cements. Materials and Methods: We used experimental resin cements containing 3 different concentrations of 10-MDP: 3.3 wt% (RC1), 6.6 wt% (RC2), or 9.9 wt% (RC3). The micro-tensile bond strength of each resin cement to dentin and a hybrid resin block (Estenia C&B, Kuraray Noritake Dental) was measured, and the fractured surface morphology was analyzed. Further, the flexural strength of the resin cements was measured using the three-point bending test. The water sorption and solubility of the cements following 30 days of immersion in water were measured. Results: The bond strength of RC2 was significantly higher than that of RC1. There was no significant difference between the bond strength of RC2 and that of RC3. The water sorption of RC3 was higher than that of any other cement. There were no significant differences in the three-point bending strength or water solubility among all three types of cements. Conclusions: Within the limitations of this study, it is suggested that 6.6 wt% 10-MDP showed superior properties than 3.3 wt% or 9.9 wt% 10-MDP in self-adhesive resin cement.

• The Journal of the Korean dental association
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• v.23 no.3 s.190
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• pp.229-235
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• 1985

• The Journal of the Korean dental association
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• v.23 no.1 s.188
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• pp.67-72
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• 1985

• The Journal of the Korean dental association
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• v.16 no.9 s.112
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• pp.683-688
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• 1978

• The Journal of the Korean dental association
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• v.15 no.12
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• pp.1009-1012
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• 1977