Işeri, U. | Özkurt, Z. | Yalniz, A. | Kazazoglu, E.

Article | 2012 | Journal of Prosthetic Dentistry107 ( 5 ) , pp.309 - 315

Statement of problem: The surface of zirconia ceramic is damaged during grinding, which may affect the mechanical properties of the material. Purpose: The purpose of this study was to compare the biaxial flexural strength of zirconia after different grinding procedures and to measure the temperature rise from grinding. Material and methods: Forty disk-shaped zirconia specimens (15 × 1.2 mm) with a smaller disk in the center of each disk (1 × 3 mm) were divided into 4 groups (n=10). The specimens were ground with a high-speed handpiece and micromotor with 2 different grinding protocols, continual grinding and periodic grinding (10 se . . .conds grinding with 10 seconds duration), until the smaller disk was removed. Control specimens without the center disk (n=10) were analyzed without grinding. The biaxial flexural strengths of the disks were determined in a universal testing machine at a crosshead speed of 0.5 mm/min. The fracture strength (MPa) was recorded, and the results were analyzed using a 1-way ANOVA, Tukey HSD test, Student's t test, and Pearson correlation test (?=05). Results: All grinding procedures significantly decreased flexural strength ( Daha fazlası Daha az

Özkurt, Z. | Tomruk, C.Ö. | Gürsoy, H. | Dölekoglu, S. | Kazazoglu, E.

Article | 2011 | Cumhuriyet Dental Journal14 ( 2 ) , pp.106 - 112

Objectives: The aim of this study was to evaluate the attitude and susceptibility of the patients who attended to Yeditepe University Faculty of Dentistry, about the cross-infection control. Methods: A questionnaire was designed to obtain information about cross-infection control in dental practices. The study population included 450 patients (277 female, 173 male) who attended to Yeditepe University Faculty of Dentistry, in December 2010. The questionnaire collected data on socio-demographic characteristics, expectations from dentists about wearing of gloves, mask, protective cap and glass, changing and renewing of these materials, . . . and infection control procedures before treatment. Descriptive statistical methods and Chi-square test were used to analyze data. An alpha level of 0.05 was used for all statistical analyses. Results: 100% of the patients expected from dentist to wear gloves, 98.9% of them expected to wear mask, 73% of them expected to wear protective cap, and 67.1% of them expected to wear protective glass. The 50.5% of the female respondents stated that all patients should wear protective glass, and this ratio is higher than male patients (37.6%) ( Daha fazlası Daha az

Malkondu, O. | Yurdagüven, H. | Say, E.C. | Kazazoglu, E. | Soyman, M.

Article | 2011 | Operative Dentistry36 ( 2 ) , pp.177 - 186

This study evaluated the effect of a highconcentration carbamide peroxide-containing home bleaching system (Opalescence PF) and a hydrogen peroxide-containing over-the-counter bleaching system (Treswhite Supreme) on the microhardness of two nanocomposites (Filtek Supreme XT and Premise) and leucitereinforced glass ceramic (Empress Esthetic), glass ceramic (Empress 2 layering), and feldspathic porcelain (Matchmaker MC). A total of 100 specimens, 20 of each kind of the restorative materials, 2 mm in thickness and 10 mm in diameter, were fabricated. Then the specimens were polished with SiC paper and 1 lm alumina polishing paste. After . . . polishing, porcelain specimens were glazed in accordance with the manufacturer's instructions. Each type of restorative material was then randomly divided into two groups (n=10), and the specimens were treated with either Opalescence PF or Treswhite Supreme. The microhardness of the specimens before bleaching (baseline) and after bleaching was determined using a digital microhardness tester. Data were analyzed using the Mann-Whitney U-test and the Wilcoxon test. Opalescence PF significantly influenced the hardness of all the restorative materials. Statistically significant decreases with respect to before bleaching were found for Premise (p=0.005), Empress Esthetic (p=0.003), Empress 2 layering (p=0.005), and Matchmaker-MC (p=0.003), whereas a increase was observed in Filtek Supreme XT (p=0.028). The difference in the microhardness values between before and after bleaching using Treswhite Supreme was statistically significant only for Premise (p=0.022). High-concentration carbamide peroxide-containing home bleaching may affect the microhardness of restorative materials Daha fazlası Daha az

Kursoglu, P. | Karagoz Motro, P.F. | Kazazoglu, E.

Article | 2015 | Journal of Prosthetic Dentistry113 ( 1 ) , pp.48 - 53

Statement of problem Understanding the translucency of ceramic materials is important to achieve good esthetics. Ceramic thickness is related to translucency; however, less information about core-veneer thickness in combination is available. Purpose The purpose of this study was to investigate the translucency parameters of core-veneer thicknesses in 2 different ceramic materials. Material and Methods A total of 56 ceramic disks of different thickness were fabricated as cores according to the manufacturer's recommendations and divided into groups (n=7). Each was veneered with its compatible veneer ceramic with a different thickness . . .(0.2, 0.5, 0.7 mm). One group of each ceramic type was left without veneer. The groups were named according to core names (group IPS e.max Press [EP], group IPS Empress Esthetic [EE]), and numbers were given according to thickness combination: 1=(1.00+0.5); 2=(0.8+0.7); 3=(1.00); 4=(0.8+0.2). All surfaces were measured by profilometry to ensure consistency within the groups. A glass disk (1.5 mm) positive control (group P) and a metal core (1.5 mm) negative control (group N) were prepared. The translucency parameter values were calculated by using spectrophotometry to calculate the color differences of the specimens over black and white backgrounds. Results A 1-way ANOVA found significant differences among the translucency parameter values of the ceramic groups (P.05). Conclusions Total ceramic thickness affected the translucency; higher combined ceramic thickness resulted in lower translucency parameter values. When total thickness decreases, the translucency of core material has more effect than that of veneer material on translucency parameter values. © 2015 Editorial Council for the Journal of Prosthetic Dentistry Daha fazlası Daha az

Malkondu, O. | Tinastepe, N. | Kazazoglu, E.

Article | 2016 | Journal of Prosthetic Dentistry116 ( 6 ) , pp.902 - 908

Statement of problem With the development of translucent zirconia, questions regarding the influence of cements on the final color of monolithic zirconia restorations have arisen. Purpose The purpose of this in vitro study was to evaluate color changes in terms of the perceptibility and acceptability of monolithic zirconia-and-cement combinations with 2 monolithic zirconia thicknesses and 3 types of cement. The translucency parameters of these combinations were also compared. Material and methods Sixty monolithic zirconia ceramic disks were milled with 2 different thicknesses (0.6 mm and 1 mm). A conventional glass ionomer cement, a . . . resin-modified glass ionomer cement, and a resin cement from the same manufacturer were applied to the ceramic surfaces of both thickness disks (n=10). Translucencies and color changes of the monolithic zirconia specimens after cement application were examined by using a spectrophotometer, and translucency parameters (TPs) and color changes (?Es) were calculated and statistically analyzed. Results Colors and TPs of the zirconia disks changed significantly after being cemented to 0.6- and 1-mm-thick disks ( Daha fazlası Daha az

Canpolat, C. | Özkurt-Kayahan, Z. | Kazazoglu, E.

Article | 2014 | Journal of Prosthetic Dentistry112 ( 3 ) , pp.418 - 422

Traumatic injuries or congenital malformations may cause soft and hard tissue defects resulting in the loss of alveolar bone and attached mucosa. Restoring the defective area presents a challenge for clinicians. The prosthetic rehabilitation of 2 patients with maxillary dentoalveolar defects with 2 different prosthetic designs is presented. The esthetic and functional requirements of the patients were fulfilled.

Capa, N. | Özkurt, Z. | Canpolat, C. | Kazazoglu, E.

Article | 2009 | Australian Dental Journal54 ( 4 ) , pp.334 - 340

Background: Bonding properties of luting cements are important for retention of restorative core materials. The aim of this study was to compare the bonding performance of a resin-modified glass ionomer cement and a self-adhesive resin cement to various fixed prosthodontic core materials. Methods: Cylindrical specimens with a thickness of 2 mm and a diameter of 5 mm were fabricated from Au-Pd-Ag, Co-Cr, Ni-Cr-Mo, Ni-Cr-Fe alloys, titanium, zirconia and Empress II (n = 20). Each group was divided into two subgroups to be luted with two different luting agents. Composite resin blocks were cemented onto specimens with RelyXUnicem and F . . .ujiCem. A shear bond strength machine with 50 kg load cell and 0.50 mm/ min crosshead speed was used. Kruskal Wallis test, Dunn's Multiple Range test and Mann-Whitney-U test were used for statistical analysis. The results were evaluated in a confidence interval of p < 0.05. Results: The highest bond strength was obtained between Ni-Cr-Fe-RelyXUnicem (8.22 ± 2.15 MPa) and the lowest was between Empress II-FujiCem (1.48 ± 0.9 MPa). In FujiCem groups, Co-Cr and Ni-Cr-Fe showed significantly higher bond strength than Au-Pd-Ag and Empress II. In RelyX Unicem groups, Ni-Cr-Fe showed higher bond strength than Empress II. Conclusions: The types of luting agents and restorative core materials may have a significant influence on bond strength. © 2009 Australian Dental Association Daha fazlası Daha az

Çapa, N. | Malkondu, Ö. | Kazazoglu, E. | Çalikkocaoglu, S.

Article | 2010 | Journal of the American Dental Association141 ( 1 ) , pp.71 - 76

Background. The authors conducted a study to evaluate the influence of dentists' and nondentists' experience, age, sex, eye color and use of eyeglasses or contact lenses on tooth shade-matching ability. Methods. The authors included 120 participants in this study conducted in Istanbul (periodontists, oral and maxillola-ciai surgeons, orthodontists, endodontists, pediatric dentists, prosthodontists, restorative dentists, general dentists in private practice, dental technicians, dental assistants, dental assistant students and laypeople). The authors assigned participants to one of three groups: group 1 was composed of prosthodontists . . ., restorative dentists and dental technicians; group 2 consisted of other dental specialists and general dentists; and group 3 included dental assistants, dental assistant students and laypeople. The authors asked participants to match the shades of three artificial maxillary right central incisors (Vitapan acrylic teeth [shades 2L1.5,1M2, 2R1.5], Vita Zahnfabrik, Bad Säckingen, Germany) by using a shade guide system (Vita Toothguide 3D-Master, Vita Zahnfabrik). They calculated shade matching for the three color components (value, hue, chroma) and analyzed the results by using a ?2 test. Results. The rate of success in matching the shade for IM2 was 53.3 percent for participants in group 1, 30 percent for participants in group 2 and 20 percent for participants in group 3 (P = .017). However, there were no significant differences between the three groups for shades 2L1.5 and 2R1.5. Professional experience (P = .003) and age (P = .027) were associated with shade-matching success for tooth shade 2L1.5 only. The results showed no statistically significant differences with respect to sex, eye color or use of eyeglasses or contact lenses. Conclusions. Dental care professionals who routinely performed restorative procedures matched the shades better than did participants in other groups. Professional experience was associated positively with the outcome, while sex, eye color and use of eyeglasses or contact lenses did not have any effect on shadematching results. Clinical Implications. To improve shade-matching skills, clinicians should participate in hands-on courses, continuing education classes and other training programs Daha fazlası Daha az

Motro, P.F.K. | Kursoglu, Pi. | Kazazoglu, E.

Article | 2012 | Journal of Prosthetic Dentistry108 ( 4 ) , pp.231 - 237

Statement of problem: Final adjustments may result in a loss of ceramic glaze, a situation which must be corrected by reglazing or polishing to obtain clinically successful restorations; such restorations may be susceptible to staining. Purpose: The purpose of this study was to determine the stainability of ceramics exposed to coffee after different surface treatments and to correlate the surface roughness with the color differences. Material and methods: Sixty-six ceramic (IPS e.maxCeram) disks (15 × 2 mm) were fabricated and glazed according to the manufacturer's instructions, then assigned to 6 groups. Group Glaze (Group G), the . . .control, was not subjected to any procedure. All the others were abraded with a diamond rotary cutting instrument. Group Reglaze (Group R) was reglazed; others were polished with different polishing materials; Group Shofu (Group S) was polished with abrasive stone (Dura-Green Stones), coarse silicon polisher (Ceramaster Coarse), silicon polisher (CeraMaster), and polishing paste (Ultra II) with polishing disks (Super-Snap Buff Disks); Group Ultradent (Group U) was polished with 1.0 and 0.5-µm polishing pastes (Ultradent Diamond) with a goat hair brush (Jiffy) and Group Bredent (Group B) was polished with an abrasive stone (Diagen turbo grinder), a round polishing brush (Abraso-fix), and polishing paste (Diamond) with felt wheels. Group Diamond rotary cutting instrument (Group D) was not treated after abrasion with a diamond rotary cutting instrument. Surface roughness was evaluated by profilometer (n=10), and 1 specimen from each group was evaluated by scanning electron microscopy (SEM). Color difference was measured by a spectrophotometer before and after 12 days of immersion in a coffee solution. Data were analyzed by 1-way ANOVA, the Tukey HSD test, and the Pearson rank correlation tests (?=.05). Results: The surface roughness (Ra) values were ordered from the highest to the lowest value, which were Group D, B, U, S, R, and G, respectively. Significant differences among groups ( Daha fazlası Daha az

Kursoglu, P. | Karagoz Motro, P.F. | Kazazoglu, E.

Article | 2014 | Journal of Prosthetic Dentistry112 ( 2 ) , pp.306 - 313

Statement of problem Stainability is an important factor in the long-term clinical success of ceramic restorations. Contour adjustments on restoration surfaces cause differences in ceramic texture that may be affected differently by the staining agent. Purpose The purpose of this study was to evaluate the surface texture obtained by different surface treatments relevant to the stainability of heat-pressed leucite-reinforced ceramic disk-shaped specimens. Material and methods Sixty-six ceramic disks (IPS Empress Esthetic) (15×2 mm) were prepared, glazed, and then assigned to 6 groups. All disks were abraded with a diamond rotary cutt . . .ing instrument except group GG (control), which was not subjected to any procedure. Group R (rotary diamond cutting instrument) was left untreated after abrasion. Group PB was polished with an abrasive stone, a round polishing brush, and paste with felt wheels. Group PU was polished with 1.0- to 0.5-µm polishing pastes with a goat-hair brush. Group PS was polished with abrasive stone, silicon carbide polishers, and polishing paste with polishing disks. Group GR was reglazed. Surface roughness was measured with a profilometer and evaluated with scanning electron microscopy. A spectrophotometer was used before and after 12 days of immersion in a coffee solution to assess color difference. Data were analyzed by 1-way ANOVA, the Tukey honestly significant difference test, and the Pearson rank correlation tests (?=.05). Results Ra values of groups from highest to lowest were, in order, R, PB, PU, PS, GR, and GG ( Daha fazlası Daha az

Dikbas, I. | Ozkurt, Z. | Kazazoglu, E.

Review | 2013 | Journal of Dental Education77 ( 1 ) , pp.85 - 92

This study was conducted to evaluate the predoctoral removable partial denture (RPD) curricula in Turkish dental schools in regards to materials, techniques, and approaches. A questionnaire consisting of eighteen multiple-choice questions was sent by e-mail to the senior members of the prosthodontic departments of seventeen long-established dental schools in Turkey. The response rate was 100 percent. All schools (100 percent) used custom trays for making final impressions of partially dentate arches, taught border molding of the custom tray for the edentulous areas, used modeling plastic impression compound in border molding the fin . . .al impression trays, and used base metal alloys for RPD frameworks. None of the schools had an in-house laboratory that fabricates RPD frameworks, and none of the students cast the frameworks of their own RPDs. The majority of schools used irreversible hydrocolloid as a final impression (70.6 percent) and dental surveyor (76.5 percent) in the designing of RPDs. The majority of schools did not flask their own RPDs (64.7 percent), did not treat patients using RPDs with attachments (76.5 percent), and did not perform the altered cast technique in bilateral and unilateral distal extension RPD cases (76.5 percent). Sixteen schools (94.1 percent) had a minimum number of RPD arches that a student must complete in order to graduate. It was found that predoctoral RPD curricula in Turkish dental schools were both variable and similar Daha fazlası Daha az

Ozkurt, Z. | Dikbas, I. | Kazazoglu, E.

Review | 2013 | Journal of Dental Education77 ( 1 ) , pp.93 - 98

The aim of this study was to evaluate predoctoral complete denture curricula in the dental schools of Turkey in terms of materials, techniques, and approaches. A questionnaire with twenty-two multiple-choice questions was prepared and sent by e-mail to the directors of the prosthodontic departments of the seventeen long-established dental schools in Turkey. All schools responded for a response rate of 100 percent. All schools (100 percent) reported using irreversible hydrocolloid impression material for preliminary impression, impression compound for border molding, zinc oxide eugenol for a final impression, and heat curing techniqu . . .e for complete denture processing. A majority of schools said they used similar materials in complete dentures: cold cured acrylic resin in fabrication of record bases (70.5 percent) and anatomic teeth for posterior region (70.5 percent). The majority of schools did not use eccentric interocclusal records (76 percent) or occlusal equilibration and face-bow preservation (94 percent) and did not treat patients who require tooth-supported overdentures (70.5 percent). None of the schools taught treatment of implant-retained overdentures in their curriculum. Eleven schools (65 percent) used positioning mandible in centric relation techniques performed by both the clinician and the patient. It can be concluded that dental schools in Turkey have different prosthodontic curricula regarding complete dentures, although some topics are the same Daha fazlası Daha az