• The Journal of Korean Academy of Prosthodontics
• /
• v.41 no.4
• /
• pp.493-502
• /
• 2003

Statement of problem : Removable partial denture and complete denture often require denture base relines to improve the fittness against tissue-bearing mucosa because of the gradual change in edentulous ridge contour and resorption of underlyng bony structure. Self-curing hard reline resins offers the immediate and relatively inexpensive means to be recondition the surface of denture base directly However weak bond between denture base resin and reline material can harbor bacteria, promote staining, or result in complete separation of the two materials. Purpose : The purpose of this study was to evaluate the effect of denture cleansers on bond strength and surface hardness of reline resin to denture base resin Denture base resin beams($60.0{\times}15.0{\times}3.0mm$) were made with Lucitone 199. Material and methods : 10mm section was removed from the center of each specimen. The samples were replaced in the molds and the space of l0mm sections were packed with Tokuso Rebase reline material. The specimens were immersed in denture cleansers (Polident, Cleadent) and were evaluated after 1 week, 2 weeks, and 4 weeks. The bond strength and surface hardness of self-curing hard reline materials to heat-curing denture base resin were measured using an UTM (universal testing machine). Results and conclusion : 1) There was no significant difference of usage, kind, and denture cleaner by application time on the bonding strength of self-curing hard reline resin to denture base resin. 2) There was no significant difference of usage, kind, and denture cleaner by application time on the surface hardness, but the surface hardness showed decreasing tendency, as the time of immersion was extended. 3) The failure modes of the specimens was initially adhesive failure and finally cohesive failure of self-curing hard reline resin.

• The Journal of Korean Academy of Prosthodontics
• /
• v.37 no.6
• /
• pp.782-790
• /
• 1999

The purpose of this study was to evaluate the effect of proportional thickness of various reline materials on the transverse strength of denture base. The denture base resin used in this study was Vertex $RS^{(R)}$ (Dentimex Zeist., Holland). The reline resins used were Tokuso $rebase^{(R)}$ normal set (Tokuyama Corp., Japan), $Rebaron^{(R)}$ (GC Corp., Japan), $Kooliner^{TM}$ (GC INC., U.S.A), New $truliner^{TM}$(Harry J. Bosworth Co., U.S.A). The bulk specimens with 2.5mm thickness of denture base were prepared as the control group. Group 1 was fabricated with 2.0mm thickness of denture base and 0.5mm reline material, group 2 with 1.5:1.0mm, group 3 with 1.0:1.5mm, group 4 with 0.5:2.0mm composition. Measurements of transverse strength were taken for each specimens The results were as follows: 1. Regardless of the reline resin type, the transverse strength of denture base was decreased after reline procedure. 2. The transverse strength according to the reline resin type was decreased in the following order : Rebaron, Tokuso rebase, Kooliner, and then New truliner and there was a significant difference among the reline materials (P<0.05). 3. The strength of the relined denture base generally decreased as the proportional thickness of the denture reline material increased. These results suggest that increasing the proportional thickness of the reline material progressively decreased the strength of the relined denture base. Thus, the denture base should not be unnecessarily altered during the reline procedure.

• The Journal of Korean Academy of Prosthodontics
• /
• v.40 no.1
• /
• pp.42-52
• /
• 2002

The purpose of this study was to evaluate the bond strength of reline resin to pressure injection type thermoplastic denture base resin. The denture base resins used in this study were $Hi-polycarbonate^{(R)}$(High Dental Co., Japan), Acetal $dental^{(R)}$(Pressingdental s.r.1., Repubblica di San Marine) of thermoplastic resin and Acron $MC^{(R)}$(GC Dental Industrial Co., Japan) of heat cured resin. The reline resins used were Lucitone $199^{(R)}$(Dentsply international Inc., USA), Tokuso $rebase^{(R)}$(Tokuyama Corp., Japan), and $Lightdon-U^{(R)}$(Dreve-Dentamid-Gmbh, Germany). The reline resins are representative of heat-cured, self-cured, and light-cured resin respectively Bond strength was examined by use of a three-point transverse flexural strength test. The results were as follows 1. The bond strength of Lucitone 199 to Acron MC was the highest. 2. The bond strengths of Lucitone 199 and Tokuso rebase to Hi-polycarbonate resulted in a value of approximately one half that of Lucitone 199 to Acron MC and there were no significant differences between these and the bond strength of Tokuso rebase to Acron MC(p<0.05) 3. The bond strengths of reline resins to Acetal dental were lower than those of reline resins to Hi-polycarbonate. 4. For all base resins Lightdon-U showed lower bond strength than the other reline resins.

• Journal of Technologic Dentistry
• /
• v.25 no.1
• /
• pp.71-79
• /
• 2003

The purpose of this study was to investigate bond strength of denture base resin repaired according to contamination. One commercial denture base resin and two different kinds of relines resin were tested; Lusiton 199(denture base resin), Vertex(reline resin) and TokusoRebase(repair resin). The specimens were processed according to the manufacturer's instructions to cured denture base resin(polymethylmethacrylate; PMMA) and reline resin. Bond strengths were examined by use of a three-point transverse flexural strength test. Data were analyzed with two-factor analysis of variance and Duncan's post-hoc test at $\alpha$=0.05. Generally, the bondstrength of heat-cured resin(Lusiton 199) was higher than the other resins. The contaminations produced an decrease in bond strength. Therefore the contamination, such as saliva or water must be avoided during the laboratory repair procedures.

• The Journal of Korean Academy of Prosthodontics
• /
• v.28 no.1
• /
• pp.25-41
• /
• 1990

The purpose of this study was to evaluate and compare the dimensional changes of relined dentures with a light-curing resin, a heat-curing resin, and a direct, hard reline resin. And also to measure the transverse strength, impact strength, surface hardness of the three resins used in relining. The surface textures of three resins also of evaluated by using scanning electron microscope. Through analyses on the data from this study, the following conclusions were obtained. 1. Impact strength of heat-curing resin was highest, and direct, hard reline resin higher, light-curing resin lowest. 2. Transverse strength of heat-curing resin was highest, and direct, hard reline resin and light-curing resin was lower and not signiicantly different. 3. Surface hardness of light-curing resin was lighest, heat-curing resin higher, and direct, hard reline resin was lowest. 4. After storage of the relined dentures for 1 day and 1 week in water at room temperature, linear shrinkage of distance between the reference points in the maxillary base relined with direct, hard reline resin was lowest, and those relined with light-curing resin and heat-curing resin were lower and were not significantly different. 5. After storage for 4 weeks in orator at room tempeature, linear shrinkage of distance between ridge crests of dentures relined with heat-curing resin was highest and that of distance between denture borders was not significantly different. 6. The dimensional changes of relined dentures during storage in water was not significant except those of distance between denture borders relined with light-curing resin at 1 day and 1 week storage in water. 7. At low magnification (x40) of SEM examination, the surface textures of three resins were similar except light-curing resin which had some defects. At high magnification (x200), the surface textures of hard, direct reline resin were smooth with little defects, but those of heat-curing resin and light-curing resin w ere irregular.

• The Journal of Advanced Prosthodontics
• /
• v.8 no.6
• /
• pp.504-510
• /
• 2016

PURPOSE. Polyamide polymers do not provide sufficient bond strength to auto-polymerized resins for repairing fractured denture or replacing dislodged denture teeth. Limited treatment methods have been developed to improve the bond strength between auto-polymerized reline resins and polyamide denture base materials. The objective of the present study was to evaluate the effect of surface modification by acetic acid on surface characteristics and bond strength of reline resin to polyamide denture base. MATERIALS AND METHODS. 84 polyamide specimens were divided into three surface treatment groups (n=28): control (N), silica-coated (S), and acid-treated (A). Two different auto-polymerized reline resins GC and Triplex resins were bonded to the samples (subgroups T and G, respectively, n=14). The specimens were subjected to shear bond strength test after they were stored in distilled water for 1 week and thermo-cycled for 5000 cycles. Data were analyzed with independent t-test, two-way analysis of variance (ANOVA), and Tukey's post hoc multiple comparison test (${\alpha}=.05$). RESULTS. The bond strength values of A and S were significantly higher than those of N (P<.001 for both). However, statistically significant difference was not observed between group A and group S. According to the independent Student's t-test, the shear bond strength values of AT were significantly higher than those of AG (P<.001). CONCLUSION. The surface treatment of polyamide denture base materials with acetic acid may be an efficient and cost-effective method for increasing the shear bond strength to auto-polymerized reline resin.

• The Journal of Korean Academy of Prosthodontics
• /
• v.31 no.4
• /
• pp.515-522
• /
• 1993

The purpose of this study was to evaluate the bond strength of rebase resin to denture base resin. The denture base resins in this study were Premium Super-20(Lang Dental Mfg. Co. Inc., Wheeling, USA) and Lucitone 199(Dentsply International Inc., York, USA). And the rebase resins were Repair Acrylic(Lang Dental Mfg. Co. Inc., Wheeling USA). Toughron Rebase(Miki Chemical Product Co. Ltd., Japan) , Tokuso Rebase(Tokuyama Soda. Co. Ltd., Japan) and Triad VLC Reline Material(Dentsply International Inc., York, USA). The obtained results were as follows : 1. The bond strength of Repair Acrylic to Premium Super-20, and that of Toughron Rebase to Lucitone 199 were the highest. 2. In Premium Super-20 and Lucitone 199, bond strength of all rebase resins had significant differences. 3. The bond strength of Triad VLC Reline Material was inclined to the lowset.

• The Journal of Korean Academy of Prosthodontics
• /
• v.41 no.2
• /
• pp.160-168
• /
• 2003

Statement of problem : Direct denture reline resins tend to discolor during service in the oral environment by intrinsic and extrinsic factor. Purpose : This study was designed to evaluate the color stability of direct denture reline resins. Material and methods : Mild Rebaron(GC Corp., Japan), Meta Base M(Sun medical Co., Japan), Mild Rebaron LC(GC Corp., Japan) and as a control group, Vertex SC(Dentimex Zeist, Holland) were chosen for this study. Ten specimens of each direct denture reline resins were fabricated. Treatment methods designed for this study were the coffee staining test(7days) and the accelerated aging test(100hours). The color changes before and after treatment were measured by Tristimulous colorimeter(Yasuda seiki seisakusho, Ltd. Japan) and analyzed. Results All the direct denture reline resins subjected to the coffee staining test and the accelerated aging test showed noticible difference in color change. After coffee staining test, Meta Base M showed the highest color change followed by Vertex SC. Mild Rebaron LC and Mild Rebaron. There were no statistical differences between Meta Base M and Vertex SC and between Mild Rebaron LC and Mild Rebaron(p>0.05). After accelerated aging test. Mild Rebaron LC showed the highest color change followed by Vertex SC, Meta Base M and Mild Rebaron. There were no statistical differences only between Mild Rebaron and Mata Base M(p>0.05) but among the others, there were statistical differences(p<0.05). Conclusion : Within the limitation of this study, all the direct denture reline resins subjected to the extrinsic and intrinsic factors showed noticible difference in color change, and there were differences among manufacturers.

• Journal of Technologic Dentistry
• /
• v.39 no.3
• /
• pp.161-167
• /
• 2017

Purpose: We compare the bond strength of heat-cured PMMA of Lucitone 199 and QC-20 and Tokuyama Rebase Resin of self-cured resin, which are widely used and well accepted in clinical practice. In order to test the mechanical bonding and chemical bonding, we will compare the bond strength between EstheShot Bright, Smiletone, Repair and Rebase resins. Methods: The denture base resin used in this study was PMMA heat-cured QC-20 and Lucitone 199, polyamide resin EstheShot Bright, Smiletone. And Two types of self-curing Rapid Repair and Tokuyama Rebase were used as resection resins. To measure the bond strength, the denture specimens were fabricated in the size of $10{\times}64{\times}3.5mm$ as instructed by the manufacturer. A surface treatment agent was applied to the cut surfaces of each denture specimen, and the specimens were placed in a preformed silicone mold, and autoclaved excimer resins were prepared. The bending strength of the fabricated specimens was measured using a universal testing machine (STM-5, United Calibration Co., U.S.A.) to measure the three-point bending strength. Results: In both polycarbonate and polyacetal resin, a special resin surface treatment agent showed higher bonding strength than the resin surface treatment agent(p<0.05). Regardless of the type of surface treatment, polycarbonate showed higher bond strength than polyacetal resin(p<0.05). Conclusion: It is considered desirable to use a special surface treating agent for the thermoplastic denture base resin such as polycarbonate and polyacetal resin.

• The Journal of Advanced Prosthodontics
• /
• v.6 no.2
• /
• pp.109-114
• /
• 2014

PURPOSE. The purpose of this study was to analyze the effect of denture cleansers on Candida albicans biofilm formation over resilient liners and to evaluate compatibility between resilient liners and denture cleansers. MATERIALS AND METHODS. Acrylic resin (Lucitone 199$^{(R)}$) and 3 resilient liners (COE-SOFT$^{TM}$, GC RELINE$^{TM}$ and SOFRELINER TOUGH TOUGH$^{(R)}$) were incubated in denture cleansers (Polident$^{(R)}$ and Cleadent$^{(R)}$) for 8 hours a day and in unstimulated saliva for 16 hours a day (n=25/gp) for 60 days. Two-way and three-way repeated measures ANOVA were performed to compare the surface roughness (Ra), pH and C. albicans binding level by radioisotope (${\alpha}$=0.05). The statistical significance of the relation between Ra and adhesion was evaluated by correlation analysis. RESULTS. The degree of Ra was significantly decreased in the following order: COE-SOFT$^{TM}$, acrylic resin, GC RELINE$^{TM}$ and SOFRELINER TOUGH$^{(R)}$. The immersion in denture cleansers significantly increased Ra of resilient liners, except for SOFRELINER TOUGH$^{(R)}$ in Cleadent$^{(R)}$. No significant differences in pH curves were observed among groups immersed in distilled water and denture cleansers. The binding levels of C. albicans were significantly decreased in the following order: COE-SOFT$^{TM}$, GC RELINE$^{TM}$, SOFRELINER TOUGH$^{(R)}$, and acrylic resin. The immersion in Cleadent$^{(R)}$ seemed to decrease C. albicans binding level on GC RELINE$^{TM}$ and SOFRELINER TOUGH$^{(R)}$. CONCLUSION. Based on the C. albicans binding levels results, it is not recommended to immerse COE-SOFT$^{TM}$ in denture cleansers, and GC RELINE$^{TM}$ and SOFRELINER TOUGH$^{(R)}$ should be immersed in Cleadent$^{(R)}$.