Comparison of the effect of different metal alloys on the esthetic appearance of dentin porcelain

Gonca Deste Gökay,Rukiye Durkan,Perihan Oyar,Gülsüm Gökçimen 한양대학교 세라믹연구소 2022 Journal of Ceramic Processing Research Vol.23 No.1

The purpose of this study was to examine the effect of aurofilm masking agents applied to various metal alloys on the colorof porcelain in metal-ceramic restorations (MCRs). The study was conducted with 2 different base-metal alloys (Ni-Cr, Co-Cr)and 2 different noble alloys (Pd-based, Au-Pd) used for MCRs, as well as 1 high noble alloy (Au-based) that served as a controlgroup. Eight experimental groups (n=7) and 1 control group were used in this study. An aurofilm masking agent was appliedto 4 groups (AuPdM, PdM, CoCr, NiCrM). Opaque porcelain and dentin body porcelain were applied to all groups. CIEL*a*b* color coordinates were measured. The Pd group had the highest mean a* value (-5.82); however, in comparisonto the control group, the differences in a* values were statistically significant only for the Cr-Co alloy groups (CoCr andCoCrM). The Pd group had the highest mean b* value (7.89). The ΔE value (2.13) of the CoCr group was significantly higherthan all other alloy groups. Metal alloy substrate and aurofilm masking agents significantly affected the color of porcelainMCRs. However, color differences between base-metal and noble alloys and the control group were within clinically acceptablelimits (ΔE<3.5).

The effect of acrylamide incorporation on the thermal and physical properties of denture resins

Ayaz, Elif Aydogan,Durkan, Rukiye,Bagis, Bora The Korean Academy of Prosthodonitics 2013 The Journal of Advanced Prosthodontics Vol.5 No.2

PURPOSE. Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature ($T_g$) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.

The effect of acrylamide incorporation on the thermal and physical properties of denture resins

Elif Aydogan Ayaz,Rukiye Durkan,Bora Bagi 대한치과보철학회 2013 The Journal of Advanced Prosthodontics Vol.5 No.2

PURPOSE Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature (Tg) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.

Peel strength of denture liner to PMMA and polyamide: laser versus air-abrasion

Korkmaz, Fatih Mehmet,Bagis, Bora,Ozcan, Mutlu,Durkan, Rukiye,Turgut, Sedanur,Ates, Sabit Melih The Korean Academy of Prosthodonitics 2013 The Journal of Advanced Prosthodontics Vol.5 No.3

PURPOSE. This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins. MATERIALS AND METHODS. Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) ($75mm{\times}25mm{\times}3mm$). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion ($50{\mu}m$), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey's test (${\alpha}$=.05). RESULTS. Denture liner tested showed increased peel strength after laser treatment with different parameters ($3.9{\pm}0.4-5.58{\pm}0.6$ MPa) compared to the control ($3.64{\pm}0.5-4.58{\pm}0.5$ MPa) and air-abraded groups ($3.1{\pm}0.6-4.46{\pm}0.3$ MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups ($3.1{\pm}0.6$ MPa). CONCLUSION. Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.

Peel strength of denture liner to PMMA and polyamide: laser versus air-abrasion

Sedanur Turgut,Sabit Melih Ate,Rukiye Durkan,Mutlu Ozcan,Bora Bagi,Fatih Mehmet Korkmaz 대한치과보철학회 2013 The Journal of Advanced Prosthodontics Vol.5 No.3

PURPOSE This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins. MATERIALS AND METHODS Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) (75 mm × 25 mm × 3 mm). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion (50 µm), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey's test (α=.05). RESULTS Denture liner tested showed increased peel strength after laser treatment with different parameters (3.9±0.4 - 5.58±0.6 MPa) compared to the control (3.64±0.5 - 4.58±0.5 MPa) and air-abraded groups (3.1±0.6 - 4.46±0.3 MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups (3.1±0.6 MPa). CONCLUSION Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.