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Öğe Assesment of normal color vision and color vision-deficient dentists success ratio on color evaluation(2012) Polat, Serdar; Tuncdemir, Ali Riza; Özturk, Caner; Tunçdemir, Makbule Tu?baObjectives: The aim of this study was to assesment of normal color vision and color visiondeficient dentists success ratio on color evaluation. Materials and Methods: Dentists who have minimum 3 years clinical experience and between 26-63 years old (n=90) were included for this study. Ishihara color blindness test was applied in all dentists before the test applying. Two pieces from each color totally 32 (13 mm × 2.4 mm) porcelain specimens were fabricated. There were 32 tabs were to be matched; the dentists were asked to mark the correct color code Results: Success rate of matching colors of color blind dentists was 33.92% ratio. The ratio in color vision dentists was 60.09%. Normal color vision dentists showed highest degree in matching at A3.5, B3, C4, D2 colors. Color vision-deficient dentists were unsuccessful in matching A1, B1, C1, B2, D2, A3 colors. Conclusions: Color vision-deficient dentists were less succesfull than normal color vision dentists in color matching.Öğe Effect of different palatal vault shapes on the dimensional stability of glass fiberreinforced heat-polymerized acrylic resin denture base material(Dental Investigations Society, 2012) Dalkiz, Mehmet; Arslan, Demet; Tuncdemir, Ali Riza; Selim Bilgin, M.; Aykul, HalilObjective: The aim of this study was to determine the effect of different palatal vault shapes on the dimensional stability of a glass fiber reinforced heat polymerized acrylic resin denture base material. Methods: Three edentulous maxilla with shallow, deep and medium shaped palatal vaults were selected and elastomeric impressions were obtained. A maxillary cast with four reference points (A, B, C, and D) was prepared to serve as control. Point (A) was marked in the anterior midline of the edentulous ridge in the incisive papillary region, points (B) and (C) were marked in the right and left posterior midlines of the edentulous ridge in the second molar regions, and point (D) was marked in the posterior palatal midline near the fovea palatina media (Figure 2). To determine linear dimensional changes, distances between four reference points (A-B, A-C, A-D and B-C) were initially measured with a metal gauge accurate within 0.1 mm under a binocular stereo light microscope and data (mm) were recorded. Results:No significant difference of interfacial distance was found in sagittal and frontal sections measured 24 h after polymerization and after 30 days of water storage in any of experimental groups (P>.05). Significant difference of linear dimension were found in all experimental groups (P<.01) between measurements made 24 h after polymerization of specimens and 30 days after water storage. Conclusion: Palatal vault shape and fiber impregnation into the acrylic resin bases did not affect the magnitude of interfacial gaps between the bases and the stone cast surfaces.Öğe Effect of different provisional cement remnant cleaning procedures including Er:YAG laser on shear bond strength of ceramics(Korean Acad Prosthodontics, 2012) Zortuk, Mustafa; Gumus, Hasan Onder; Kilinc, Halil Ibrahim; Tuncdemir, Ali RizaPURPOSE. The purpose of this study was to evaluate the effect of provisional cement removal by different dentin cleaning protocols (dental explorer, pumice, cleaning bur, Er:YAG laser) on the shear bond strength between ceramic and dentin. MATERIALS AND METHODS. In total, 36 caries-free unrestored human third molars were selected as tooth specimens. Provisional restorations were fabricated and cemented with eugenol-free provisional cement. Then, disc-shaped ceramic specimens were fabricated and randomly assigned to four groups of dentin cleaning protocols (n = 9). Group 1 (control): Provisional cements were mechanically removed with a dental explorer. Group 2: The dentin surfaces were treated with a cleaning brush with pumice Group 3: The dentin surfaces were treated with a cleaning bur. Group 4: The provisional cements were removed by an Er:YAG laser. Self-adhesive luting cement was used to bond ceramic discs to dentin surfaces. Shear bond strength (SBS) was measured using a universal testing machine at a 0.05 mm/min crosshead speed. The data were analyzed using a Kolmogorov Smirnov, One-way ANOVA and Tukey HSD tests to perform multiple comparisons (alpha=0.05). RESULTS. The dentin cleaning methods did not significantly affect the SBS of ceramic discs to dentin as follows: dental explorer, pumice, cleaning bur, and Er:YAG laser. CONCLUSION. The use of different cleaning protocols did not affect the SBS between dentin and ceramic surfaces. [J Adv Prosthodont 2012;4:192-6]Öğe The effect of luting cement thicknesses on the push-out bond strength of the fiber posts(Taylor & Francis Ltd, 2013) Ozcan, Erhan; Cetin, Ali Riza; Tuncdemir, Ali Riza; Ulker, MustafaObjective. The aim of this study was to evaluate the effect of luting cement thicknesses on the push-out bond strength of the fiber posts. Materials and methods. Sixty human maxillary canine teeth were endodontically treated. Post spaces were prepared and root specimens randomly divided into three groups: Group 1: etch-and-rinse (Variolink II/Exite DSC), Group 2: self-etch (Panavia F2.0/ED primer) and Group 3: self-adhesive (Clearfil SA Cement). Then each group was divided into four sub-groups according to the cement thickness, as follows: Sub-group 1: 0.35 mm, Sub-group 2: 0.25 mm, Sub-group 3: 0.15 mm, and Sub-group 4: 0.05 mm. Three slices of 1 mm thickness were obtained from each root specimen (n = 15). Push-out tests were performed and data was analyzed with two-way ANOVA and Tukey tests. Results. The etch-and-rinse system (Variolink II) had a significantly higher bond strength compared with the other systems (p < 0.05). The thickest cement group (0.35 mm) had a significantly lower bond strength compared with the 0.15 and 0.05 mm groups in the etch-and-rinse and self-adhesive groups (p < 0.05). In the self-etch group, the cement thicknesses did not significantly affect the bond strength (p > 0.05). Conclusions. The etch-and-rinse system offered better bonding to root dentine than the self-adhesive and self-etch systems. The increases in cement thickness significantly reduced the bond strength of fiber posts to root dentine for both the etch-and-rinse and self-adhesive systems.Öğe The effect of post surface treatments on the bond strength of fiber posts to root surfaces(Springer London Ltd, 2013) Tuncdemir, Ali Riza; Yildirim, Cihan; Guller, Fatma; Ozcan, Erhan; Usumez, AslihanThe aim of the present study was to evaluate the influence of post surface treatment methods on the push-out bond strength of adhesively luted quartz fiber posts. Thirty freshly extracted and endodontically treated human incisor teeth were prepared for quartz fiber posts. The posts were submitted to three different surface treatments (n = 10), including no treatment, 50-A mu m aluminum-oxide (Al2O3) airborne-particle abrasion and Er:YAG laser (10 Hz, 150 mJ) irradiation. The posts were luted with resin cement. Each root was sectioned perpendicularly to its long axis to create specimens of 1-mm thickness. After the specimens were stored in distilled water at 37A degrees C for 24 h, their push-out bond strength was tested using a universal testing machine at a crosshead speed of 1 mm/min. The data were analyzed by two-way ANOVA (alpha = .05). The two-way ANOVA indicated that push-out test values did not vary significantly according to surface treatments applied (control, airborne particle abrasion, Er:YAG laser irradiation) (p > 0.05), however, values varied according to the root segments (cervical, middle, and apical) (p < 0.01). The push-out bond strength values of the coronal root sections were the highest (p < 0.05) and there were no significant differences between the middle and apical root sections in push-out bond strength of fiber posts (p > 0.05). Air-borne particle abrasion or Er:YAG laser irradiation applied on the quartz fiber posts did not affect the push-out bond strengths relative to the root surfaces. The highest bond strength was observed in the cervical third of the roots in all groups.Öğe The effect of repeated porcelain firings on corrosion resistance of different dental alloys(Korean Acad Prosthodontics, 2013) Tuncdemir, Ali Riza; Karahan, Ismail; Polat, Serdar; Malkoc, Meral Arslan; Dalkiz, MehmetPURPOSE. The aim of this study was to evaluate the effects of repeated porcelain firing process on the corrosion rates of the dental alloys. MATERIALS AND METHODS. Cr-Co, Cr-Ni and Pd-Ag alloys were used for this study. Each metal supported porcelain consisted of 30 specimens of 10 for 7, 9 and 11 firing each. Disc-shaped specimens 10 mm diameter and 3 mm thickness were formed by melting alloys with a propane-oxygen flame and casted with a centrifuge casting machine and then with the porcelain veneer fired onto the metal alloys. Corrosion tests were performed in quintuplicate for each alloy (after repeated porcelain firing) in Fusayama artificial saliva solution (pH = 5) in a low thermal-expansion borosilicate glass cell. Tamhane and Sheffe test was used to compare corrosion differences in the results after repeated firings and among 7, 9 and 11 firing for each alloy. The probability level for statistical significance was set at alpha=0.05. RESULTS. The corrosion resistance was higher (30 mV), in case of 7 times firing (Commercial). On the other hand, it was lower in case of 11 times firing (5 mV) (P<.05). CONCLUSION. Repeated firings decreased corrosion resistance of Pd-Ag, Cr-Co and Cr-Ni alloys. The Pd-Ag alloy exhibited little corrosion in in vitro tests. The Cr-Ni alloy exhibited higher corrosion resistance than Cr-Co alloys in in vitro tests. [J Adv Prosthodont 2013;5:44-501Öğe Effects of different surface treatments on shear bond strength in two different ceramic systems(Springer London Ltd, 2013) Yavuz, Tevfik; Dilber, Erhan; Kara, Haluk Baris; Tuncdemir, Ali Riza; Ozturk, A. NilgunThe purpose of this study was to evaluate the influence of different surface treatments (sandblasting, acid etching, and laser irradiation) on the shear bond strength of lithium disilicate-based core (IPS Empress 2) and feldspathic ceramics (VITA VM 9). One hundred ceramic discs were divided into two groups of 50 discs each for two ceramic systems: IPS Empress 2 (group I) and VITA VM 9 (group II). Each of the two groups was further divided into five surface treatment groups (ten each) as follows: group SB, sandblasting with alumina particles (50 mu m); group HF, 5 % hydrofluoric acid etching; group L, Er:YAG laser irradiation (distance, 1 mm; 500 mJ; 20 Hz; 10 W; manually, noncontact R14 handpiece); group SB-L, sandblasting + Er:YAG laser; and group HF-L, 5 % hydrofluoric acid + Er:YAG laser. Luting cement (Panavia 2.0) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, a shear bond strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed with a two-way analysis of variance (ANOVA) and Tukey's honestly significant difference tests (alpha = 0.05). The two-way ANOVA indicated that the shear bond strength was significantly affected by the surface treatment methods (p < 0.05), but there was no significant interaction between the ceramic systems. Group SB-L had the highest mean values for each ceramic system. Sandblasting, followed by Er:YAG laser irradiation, enhanced the bond strength, indicating its potential use as an alternative method. The atomic force microscopic evaluation revealed that group SB had the most distinct sharp peaks among the groups.Öğe Effects of fibers on the color change and stability of resin composites after accelerated aging(Japanese Soc Dental Materials Devices, 2012) Tuncdemir, Ali Riza; Aykent, FilizComposite resins were reinforced with glass and polyethylene fibers in this study, and the effect of fiber reinforcement on the color change of composite resins was investigated. After accelerated aging, the effect of fiber reinforcement on the color stability of composite resins was also examined. There were three experimental groups (n=12 disks per group): non-fiber-reinforced composite (non-FRC control), polyethylene fiber (Ribbond-THM)-reinforced composite, and glass fiber (everstick NET)-reinforced composite. According to the critical remarks of color change of National Bureau of Standarts (NSB), glass fiber-reinforced anterior composites showed trace color change and polyethylene-fiber reinforced composites showed slight color change before accelerated aging. After accelerated aging, both control and fiber-reinforced composite groups showed noticeable color change. It was concluded that both the types of fiber reinforcement and composite resin influenced the color change of fiber-reinforced composite resins.Öğe Inadequate shear bond strengths of self-etch, self-adhesive systems for secure orthodontic bonding(Japanese Soc Dental Materials Devices, 2012) Isman, Eren; Karaarslan, Emine Sirin; Oksayan, Ridvan; Tuncdemir, Ali Riza; Usumez, Serdar; Adanir, Nejdet; Cebe, Mehmet AtaThis study evaluated the shear bond strength (SBS) of a traditional orthodontic bracket bonding agent (Transbond XT) against two self-etch, self-adhesive systems (Maxcem Elite and Vertise Flow). Sixty premolar teeth and sixty brackets were randomly and equally divided into five groups: Transbond XT (TXT) as the control, Maxcem Elite (ME) without etching, ME with etching (ME/Etch), Vertise Flow (VF) without etching, and VF with etching (VF/Etch). Respective SBS results of the five groups were 9.86 +/- 3.20, 4.67 +/- 2.94, 7.82 +/- 2.56, 2.55 +/- 0.77, and 7.89 +/- 1.17 MPa. SBS values of the new self-etch adhesive systems were significantly lower than the traditional etch-and-rinse control (p<0.005). However, no significant differences were found between TXT and the self-adhesives applied with etching (p>0.005). After debonding, ARI scores 0 and 1 were predominant in non-etched ME and VF groups. It was concluded that new self-etch, self-adhesive bonding systems require additional phosphoric acid application to achieve comparable SBS values as the traditional orthodontic bonding agent.Öğe Influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents(Springer, 2013) Ozcan, Erhan; Cetin, Ali Riza; Capar, Ismail Davut; Tuncdemir, Ali Riza; Aydinbelge, Hale AriThis study evaluated the influence of eugenol on the push-out bond strengths of fiber posts cemented with different types of resin luting agents. Seventy-two extracted maxillary single-rooted canine teeth were randomly divided into two groups of 36 teeth. Group 1, the control group, was filled with gutta-percha only (i.e., did not receive eugenol), whereas group 2 was filled with a eugenol-containing sealer. All root canals were filled and each group was divided into three subgroups. The posts in each subgroup were cemented with the following materials: subgroup 1 with a 2-step self-etching adhesive system (Clearfil Liner Bond 2V + Panavia F); subgroup 2 with a 1-step self-etching adhesive (Panavia F); and subgroup 3 with a self-adhesive (Clearfil SA Cement). Dislodgement resistance was measured using a universal testing machine. All data were subjected to ANOVA using a factorial design and Tukey test (alpha = 0.05). The use of the eugenol-containing sealer significantly reduced the push-out bond strength of the fiber post (P < 0.05). The push-out bond strength of Panavia F was significantly higher than those of the other groups filled with the eugenol-containing sealer (P < 0.05). The Panavia F group was less susceptible to the inhibiting effect of eugenol than were the other evaluated groups when the fiber post was cemented in the canals filled with the eugenol-containing sealer.Öğe The relationship of some patients factors with shade of their teeth measured by spectrophotometry in Turkish people(Professional Medical Publications, 2012) Tuncdemir, Ali Riza; Gungor, Ahmet Y.; Kahraman, BahadirObjective: To investigate the relationships of some patients' factors with the shade of their teeth in Turkish people. Methodology: Four Hundred subjects who had no defects in their natural right maxillary central incisors were examined in this study. Shade of teeth was measured with a spectrophotometer. Eye colours were classified as brown, honey, hazel, green, black and blue respectively. Skin complexions were determined by using the Fitzpatrick Skin Type Classification. Tooth shades were placed into 13 categories using the vita shade scale, and skin complexion in 6 categories. The Pearson Chi-Square and Likelihood Ratio statistical tests were used to analyze the data. Results: There was no correlation between the skin complexion and tooth shade (P > 0.05). Statistically significant differences were found between gender and tooth shade (P < 0.05). People with their ages between 14-30 and 31-45 generally had A2 tooth shade, and those who were between the ages of 46-60 and 61-80 generally had A3 tooth shade. There was a statistically significant correlation between age and tooth shade (P < 0.05). People having hazel, brown, blue and black eyes had A2 shade teeth and those with honey and green eyes generally had teeth with the A3 shades. There were no statistically significant correlations between eye and tooth shade (P > 0.05). Conclusion: Within the limitations of this study, there were no significant relationships between skin complexion, eye color and tooth shade. Younger people generally had A2 shade teeth. Elderly people were more likely to have darker teeth.
