• Restorative Dentistry and Endodontics
• /
• v.19 no.2
• /
• pp.447-459
• /
• 1994

The purpose of this study is to evaluate of shear bond strength of light-curing composite resin to light-curing glass ionomer cement. Composite resin and glass ionomer cement have been widely used as an esthetic filling materials in dental clinics. To achieve better clinical results, sandwich technic was developed with conpensating for disadvantages of these two materials. Especially, light-curing glass ionomer cement provided greately improved bonding strength of teeth or composite resin, and then excellent clinical results can be acquired. In this study, 6 commercial light-curing glass ionomer cements(3 commercial restorative materials : Fuji II LC, Variglass VLC, Vitremer, and 3 commercial lining materials : Fuji Lining LC, Baseline VLC, Vitrebond) were devided two groups. According to manufacturer's appointment, no surface treatment was referred to N groups. Supposing. of clinical practice, surface grinding with water spray at 320 grit sand paper, 40 seconds etching with 37% phosphoric acid, 20 seconds washing, 20 seconds air drying was referred to N groups. Totally 12 experimental groups were devided, and all 120 specimens from 10 specimens of each groups were made. After light-curing composite resin was bonded to light-curing glass ionomer cement, shear bond strength was tested by Instron universal testing machine between glass ionomer cement and composit resin. The data were analyzed statistically by Student's t-test and ANOVA. The obtained results were as follows; 1. In light-curing glass ionomer cement, restorative materials showed higher shear bond strength to composite resin than lining materials(p<0.05). 2. Variglass VLC of restorative material group and Baseline VLC of lining material group have highest shear bond strength to composite resin(p<0.001). 3. In light-curing glass ionomer cement, surface grinding and acid etching reduced shear bond strength to composite resin(p<0.001)}. 4. VGN group 1s highest shear bond strength to composite resin, VBE group is lowest shear bond strength to composite resin(p<0.001).

• Restorative Dentistry and Endodontics
• /
• v.20 no.1
• /
• pp.97-112
• /
• 1995

The purpose of this study was to evaluate the effect of wetting condition made by drying time on bonding of resin cement to dentin. Freshly extracted bovine teeth were grinded to expose flat dentin surfaces. After the exposed dentin surfaces were treated with pretreatment agents and water rinse, each wetting condition of dentin surfaces was made according to drying times and methods including slight blow bry for I-second by air syringe, blow dry for 20-second by air syringe, and 12-hour dry in desiccator respectively. and then, previously made composite resin specimens were bonded onto each conditioned dentin surface of the specimen using Panavia-21(Kuraray Co.), Bistite(Tokuso Co.), and Choice(use with All bond-2, Bisco Inc.) resin cement according as manufacturer's instruction. Bonded specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured, cohesive failure rate was calculated, and fractured dentin surfaces and acrylic rod sides were examined under scanning electron microscope. The result were as follows ; In the group of bonding with Panavia-21 resin cement, higher tensile bond strength was seen in 12-hour dry group than in I-second and 20-second dry group(p<0.01). In the group of bonding with Bistite resin cement, higher tensile bond strength was seen in 1-second dry group than in 20-second and 12-hour dry group(p<0.01). In the group of bonding with Choice resin cement, no significant differences of bond strength under given drying time were seen. Cohesive failure rates derived from the groups of bonding with Panavia-21 and Choice resin cement were increased with the increase of tensile bond strength in each drying time. On SEM examination of fractured surface, adhesive failure mode with fractured resin tags was mostly seen in wet condition with I-second drying time in the group of bonding with Panavia-21 resin cement, mixed failure mode with shortened and fractured resin tag was seen in the group of bonding with Bistite resin cement, and regardless of drying time, and cohesive-adhesive mixed failure mode with fracture of 'Hollow' typed resin tags was mainly seen in the group of bonding with Choice resin cement.

• The korean journal of orthodontics
• /
• v.20 no.3 s.32
• /
• pp.583-591
• /
• 1990

If the bond strength is sufficient to resist orthodontic force, orthodontic brackets can be bonded to restorations. Orthodontic brackets were bonded to composite resin and glass ionomer cement restorations with no-mix adhesive or glass ionomer cement. The shear bond strength of adhesives bonded to restorations was studied in vitro. Orthodontic brackets were bonded to 10 extracted natural teeth, 40 composite resin restorations and 40 glass ionomer restorations. The surfaces of composite resin restorations were roughened or applied with bonding agent (Scothbond) after surface roughening. The surfaces of glass ionomer cement restorations were conditioned with acid etching or applied with Scotchbond to etched surface. The adhesive was no-mix resin or glass ionomer cement. The shear bond strength was measured. The results were as follows: 1. Orthodontic brackets could be bonded to composite resin restorations effectively as they could be bonded to acid etched enamel with no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was not affected by bonding agent greatly. 2. The shear bond strength of no-mix adhesive bonded to acid etched glass ionomer cement restorations was sufficient to resist orthodontic force. However. the fracture risk of glass ionomer cement restorations was increased during debonding. The bonding agent couldn't increase the shear bond strength greatly. 3. The shear bond strength of glass ionomer cement bonded to glass ionomer cement restorations was lower than that of no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was greatly decreased by bonding agent. 4. The shear bond strength of glass ionomer cement bonded to composite resin restorations was too low to resist orthodontic force.

• The Journal of Advanced Prosthodontics
• /
• v.10 no.1
• /
• pp.1-7
• /
• 2018

PURPOSE. The aim of this study was to evaluate the effects of abutment diameter, cement type, and re-cementation on the retention of implant-supported CAD/CAM metal copings over short abutments. MATERIALS AND METHODS. Sixty abutments with two different diameters, the height of which was reduced to 3 mm, were vertically mounted in acrylic resin blocks with matching implant analogues. The specimens were divided into 2 diameter groups: 4.5 mm and 5.5 mm (n=30). For each abutment a CAD/CAM metal coping was manufactured, with an occlusal loop. Each group was sub-divided into 3 sub-groups (n=10). In each subgroup, a different cement type was used: resin-modified glass-ionomer, resin cement and zinc-oxide-eugenol. After incubation and thermocycling, the removal force was measured using a universal testing machine at a cross-head speed of 0.5 mm/min. In zinc-oxide-eugenol group, after removal of the coping, the cement remnants were completely cleaned and the copings were re-cemented with resin cement and re-tested. Two-way ANOVA, post hoc Tukey tests, and paired t-test were used to analyze data (${\alpha}=.05$). RESULTS. The highest pulling force was registered in the resin cement group (414.8 N), followed by the re-cementation group (380.5 N). Increasing the diameter improved the retention significantly (P=.006). The difference in retention between the cemented and recemented copings was not statistically significant (P=.40). CONCLUSION. Resin cement provided retention almost twice as strong as that of the RMGI. Increasing the abutment diameter improved retention significantly. Re-cementation with resin cement did not exhibit any difference from the initial cementation with resin cement.

• Restorative Dentistry and Endodontics
• /
• v.22 no.1
• /
• pp.132-143
• /
• 1997

Recently composite resin luting cement have been widely used according as esthetic requirement was increased. The purpose of this study was to evaluate of shear bond strength of four resin cements to bovine dentin. The materials used in this study were All-Bond 2(dentin bonding agent), Duolink cement, Bistite resin cement, Twinlook cement, Clearfil CR inlay cement. A total 40 acrylic cylinders with bovine dentin were divided into four groups. Four experimental groups were as follows; Group l(AB) : Specimens bonded with All-Bond 2 and Duolink Cement Group 2(BT) : Specimens bonded with Bistite Resin Cement Group 3(TL) : Specimens bonded with Twinlook Cement Group 4(CR) : Specimens bonded with Clearfil CR Inlay Cement Mter 1 hour of bonding, all specimens were stored for 24 hours in water at $37^{\circ}C$ and tested with Instron universal testing machine between bovine dentin and resin cements. The data were evaluated statistically at the 95% confidence level with a one-way analysis of variance and Tukey's range statistics. The following results obtained; 1. The group l(AB) was highest shear bond strength and the group 3(TL) was 10west(p>0.05). 2. Group 2(BT), 4(CR) were similar shear bond strength and there was no significant difference(p<0.05). 3. Group 1(AB), 4(CR) with acid etching were showed resin tags on the opened dentinal tubules, but Group 2(BT), 3(TL) without acid etching were not showed resin tags. 4. Group l(AB) was showed intimate adaptation than other groups.

• The Journal of Korean Academy of Prosthodontics
• /
• v.40 no.4
• /
• pp.365-373
• /
• 2002

The purpose of this study was to investigate the effects of desensitizer on shear bond strength of adhesive resin cements for all ceramic crown. For this study, Gluma $desensitizer^{(R)}$(Heraeus Kulzer, Germany) and MS $Coat^{(R)}$(Sun medical, Japan) were used as desensitizer, and Bistite $II^{(R)}$ resin cement(Tokuyama, Japan) and Variolink $II^{(R)}$ resin cement (Ivoclar, Liechtenstein) were used. IPS Empress ceramics were bonded to dentin surfaces after application of desensitizer and shear bond strength of specimens were measured using UTM(Zwick 1456 41. Zwick, Germany) at a crosshead speed of 1mm/min. The obtained results were as follows : 1. The shear bond strength of both resin cements were not affected by Gluma $desensitizer^{(R)}$ containing HEMA 2. The shear bond strength of Bistite $II^{(R)}$ resin cement was significantly decreased by MS $Coat^{(R)}$. 3. The failure mode in MS $Coat^{(R)}-Bistite \;II^{(R)}$ group was mainly adhesive type between dentin and resin cement. but that of Gluma $desensitizer^{(R)}$-Variolink $II^{(R)}$ group was mainly mixed type, combined adhesive failures between dentin and resin cement or porcelain and resin cement.

• The Journal of Advanced Prosthodontics
• /
• v.7 no.6
• /
• pp.475-483
• /
• 2015

PURPOSE. The objective of this study was to evaluate the influence of various cement types on the stress distribution in monolithic zirconia crowns under maximum bite force using the finite element analysis. MATERIALS AND METHODS. The models of the prepared #46 crown (deep chamfer margin) were scanned and solid models composed of the monolithic zirconia crown, cement layer, and prepared tooth were produced using the computer-aided design technology and were subsequently translated into 3-dimensional finite element models. Four models were prepared according to different cement types (zinc phosphate, polycarboxylate, glass ionomer, and resin). A load of 700 N was applied vertically on the crowns (8 loading points). Maximum principal stress was determined. RESULTS. Zinc phosphate cement had a greater stress concentration in the cement layer, while polycarboxylate cement had a greater stress concentration on the distal surface of the monolithic zirconia crown and abutment tooth. Resin cement and glass ionomer cement showed similar patterns, but resin cement showed a lower stress distribution on the lingual and mesial surface of the cement layer. CONCLUSION. The test results indicate that the use of different luting agents that have various elastic moduli has an impact on the stress distribution of the monolithic zirconia crowns, cement layers, and abutment tooth. Resin cement is recommended for the luting agent of the monolithic zirconia crowns.

• The Journal of Korean Academy of Prosthodontics
• /
• v.42 no.1
• /
• pp.41-48
• /
• 2004

Statement of problem : The Cement as well as restoration required esthetics for making natural color restoration. Purpose : The purpose of this research is to evaluate color stability of restoration intermediated by resin cement which is used for cementation of all ceramic crown. Material and method : After making Empress 2 ingot into the size of $10mm{\times}10mm{\times}1mm$ according to indication, it glazed and made 48 Empress 2 blocks. Three kinds of resin cement(Rely-X, Variolink 2, Choice) having same shade cemented between Empress 2 blocks and Ivory shade tiles and made 48 specimens in the thickness of $30{\mu}m$ and $80{\mu}m$. After measureing color difference using spectorphotomenter, the result of this study were as follows. Results : The color difference of resin cement used in experiment increased in the order Rely-X, Variolink 2. As the thickness of cement increases, the color difference of all kinds of cement found statistically sifnificant difference but, this result is clinically acceptable. Conclusion : More resarch would have to be done in order to decrease the color difference as cement's thickness.

• The Journal of Korean Academy of Prosthodontics
• /
• v.31 no.4
• /
• pp.506-514
• /
• 1993

The purpose of this study was to evaluate the effect of porcelain laminate thickness on polymerization of resin cement. G-Cera resin bonding system(G-C int., Japan) was used in this study and Heliolux II (Vivadent, Austria) was used for polymerization of resin cement. The thickness of porcelain laminates used in this study were 0.5mm, 1.0mm and 1.5mm and the degree of polymerization of resin cement was measured by microhardness theater(Matsuzawa, Model MXT-70, Japan). The obtained results were as follows : 1. The surface hardness of resin cements increaing the thickness of poreclain laminate was decreased. 2. The surface hardness of resin cements increasing the curing time was decreased.

• Restorative Dentistry and Endodontics
• /
• v.20 no.1
• /
• pp.152-163
• /
• 1995

This experiment was performed to observe the adhesion pattern and microleakage in the gingival margin according to variation in the resin cement thickness which results from thickness of Die spacer. which is considered to effect the adaptability of the composite resin inlays. Clearfil CR inlays were fabricated on stone models with CR Sep applicated once and Nice fit twice, 4 times, and 6 times each. After 2nd curing within the CRC-100 oven, CR inlays were cemented with CR inlay cement. Dye(2% methylene blue) penetration and adhesion pattern were evaluated after sectioning of gingival margin into :3 pieces. The results were as follows ; 1. The thickness of resin cement showed unevenchanging pattern with that of die spacer, namely, it was increased until 4 times' application of Nice-Fit but was decreased with 6 times' application of that. 2. The degree of dye penetration wasn't affected by cement thickness within a limited value. 3. Most of dye penetration was shown through the interface between cement and enamel rather than the interface between cement and CR inlay. This shows that the affinity of resin cement for CR inlay was superior to the adhesive strength with tooth structure. 4. No gap was found at the interface between enamel and cement but some showed separation between dentin and cement. It is concidered that the contraction force of cement was less than the bond strength with the enamel. 5. Lots of voids were found in the CR inlay and resin cement. There was a pooling tendency of bonding agent and cement in the axiogingival line angle portion. 6. In some specimens, cracks were shown in enamel margin. From this it could be considered that cavity preparation and surface treatment weakened the tooth structure.