Alper Kapdan

Evaluation of the surface roughness of zirconia ceramics after different surface treatments

Abstract Objective. This study aimed to investigate the effects of different mechanical surface treatments of pre-sintered zirconium oxide (ZrO2) in an attempt to improve its bonding potential. Materials and methods. One hundred and twenty IPS e-max ZirCAD (Ivoclar Vivadent) pre-sintered zirconia blocks (7 mm diameter, 3 mm height) received six different surface treatments (n = 20): Group C was untreated (control); Group E was Er:YAG laser irradiated; Group N was Nd:YAG laser irradiated; Group SB was sandblasted, Group SN was sandblasted and Nd:YAG laser irradiated; and Group SE was sandblasted and Er:YAG laser irradiated. After the surface treatments, the average surface roughness (Ra, µm) of each specimen was determined with a profilometer, then all the specimens were sintered. The surface roughness values were analysed through one-way ANOVA and Tukeys test. Changes in the morphological characteristics of ZrO2 were examined through scanning electron microscopy (SEM). Results. Sintered sandblasted, Er:YAG laser treatment, sandblasted + Er:YAG laser and sandblasted + Nd:YAG laser irradiation resulted in a rougher surface than the other treatments. Conclusion. Nd:YAG laser irradiation alone was not effective in altering the zirconia surface morphology.

Effects of dentin surface treatments including Er,Cr:YSGG laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin

Abstract Objective. Intra-canal post systems are commonly used to restore root-filled teeth. Bond strengths of the posts can be affected by various surface treatments of the post or the dentin. The aim of this study was to evaluate the effects of dentin surface treatments including erbium-chromium; yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin. Materials and methods. Forty single-rooted human maxillary incisors were filled and post spaces were prepared. After these procedures, the specimens were divided randomly into four groups according to the dentin surface treatments, as follows: (i) untreated surface (control), (ii) 1W Er,Cr:YSGG laser application, (iii) 2W Er,Cr:YSGG laser application and (iv) 3W Er,Cr:YSGG laser application. Then the posts were cemented into the root canals using dual-cured resin cement. Bonded specimens were cut into 1-mm-thick slices and push-out tests were performed using a universal testing device. All specimens were loaded until fracture and the failure modes were evaluated with a stereomicroscope at 32× magnification. Representative specimens were analyzed by scanning electron microscopy. Data were analyzed using a one-way ANOVA, Tukey and Wilcoxon tests. Results. The bond strength values ranged from 3.22–4.68 MPa. There were no statistically significant differences among the groups, regardless of the different levels. The coronal and middle levels of the post space had significantly higher bond strength values compared with the apical level (p < 0.05). Conclusion. Er,Cr:YSGG laser irradiation with different intensities did not increase the bond strength of the fiber posts to the root canal dentin walls.

Veneer Ceramic to Y‐TZP Bonding: Comparison of Different Surface Treatments

PURPOSE The purpose of this study was to evaluate the effects of various surface-treatment techniques for enhancing the bond strength between veneering ceramic and yttria-stabilized tetragonal zirconia polycrystals (Y-TZP). MATERIALS AND METHODS Pre-sintered Y-TZP specimens were divided into eight groups (n = 10) according to the surface-treatment technique used: (a) untreated (control); (b) air abrasion with aluminum oxide particles; (c) erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation at different energy intensities (1 to 6 W). All specimens were then sintered and veneered with veneering ceramic according to the manufacturers instructions. The obtained zirconia-ceramic specimens were immersed in 37°C distilled water for 24 hours before a shear bond strength test using a universal testing device at a 1 mm/min crosshead speed. The average values were calculated. After debonding, the Y-TZP surfaces were examined under a stereomicroscope to determine their fracture pattern, and the surface topography was evaluated with scanning electron microscopy after surface treatments. RESULTS The bond strength ranged from 13.24 to 20.54 MPa. All surface treatments increased the bond strength between the veneering ceramic and Y-TZP; however, the value for the 6 W irradiation group was significantly different from the values for other groups (p ˂ 0.05). CONCLUSIONS The present studys findings showed that higher energy densities were needed for the laser irradiation to improve the bond strength between the veneering ceramic and zirconia. CLINICAL IMPLICATION Y-TZP is commonly used as a core material in fixed restorations. The bond strength between zirconia and the veneering ceramic can be affected by various surface treatments.

Resin cement to indirect composite resin bonding: Effect of various surface treatments

Debonding at the composite-adhesive interface is a major problem for indirect composite restorations. The aim of this study was to evaluate the bond strength (BS) of an indirect composite resin after various surface treatments (air-abrasion with Al2O3, phosphoric acid-etchig and different applications of NdYAG laser irradiations). Fifty composite disks were subjected to secondary curing to complete polymerization and randomly divided into five experimental groups (n = 10) including Group 1, untreated (control); Group 2, phosphoric acid-etched; Group 3, air-abrasion with Al2 O3 ; Group 4, Nd:YAG laser irradiated with non-contact and Group 5, Nd:YAG laser irradiated with contact. They were then bonded to resin cement and shear BS was determined in a universal testing device at a crosshead speed of 1 mm/min. One way analysis of variance (ANOVA) and Tukey post-hoc tests were used to analyze the BS values. The highest BS value was observed in Group 4 and followed by Group 3. Tukey test showed that there was no statistical difference between Group1, 2 and 5. Furthermore, differences in BSs between Group 4 and the other groups except Group 3 were significant (p < 0.05) and also there were significant differences in BSs between Group 3 to 1 and Group 3 to 2 (p < 0.05). This study reveals that air-abrasion with Al2 O3 and Nd:YAG laser irradiation with non-contact provided a significant increase in BS between indirect composite and resin cement.

Efficacy of Surface Roughness and Bond Strength of Y-TZP Zirconia After Various Pre-Treatments

OBJECTIVE The aim of this study was to evaluate surface roughness (SR) and the influence of various surface treatments (STs) on the veneer ceramic shear bond strength (SBS) to Y-TZP zirconia. BACKGROUND DATA STs can improve the bonding properties of zirconia ceramics. However, little is known about the effect of Er,Cr:YSGG laser irradiation on SBS between zirconia and veneer ceramic/resin cement. METHODS Eighty ceramic discs of yttria-tetragonal zirconia polycrystals (Y-TZP) were prepared, and specimens were divided into eight groups (n=10): untreated (control), air abrasion, and Er,Cr:YSGG laser irradiation with different energy intensities (1-6 W). Average SR of each specimen was determined with a profilometer, and a veneering ceramic recommended for zirconia was fired into cylinder-shaped Y-TZP specimens. SBS test was performed for each specimen at a crosshead speed of 1 mm/min, and the average means of SBS and SR were calculated. Fracture modes and the surface topography were evaluated with various microscopes after STs. Data were analyzed by using one way analysis of variance (ANOVA) and Tukey honest significant difference (HSD) tests. RESULTS The highest mean force value was observed in the air abrasion group, and followed by 6 and 5 W laser irradiations, respectively. The difference between control and air abrasion groups was found to be statistically significant (p<0.05). All laser irradiations increased the SBS value, but 1 and 2 W laser irradiations showed no statistically significant differences compared with the control group. However, the SR value for air abrasion group was significantly higher than that of the control group and 1 W (p<0.05), and there were no significant differences between the SR of all the laser groups and the control group. CONCLUSIONS The result of this study showed that STs with air abrasion and high laser energy intensities (3-6W), can improve the bonding properties of Y-TZP zirconia.

Efficacy of ceramic repair material on the bond strength of composite resin to zirconia ceramic

Abstract Objective. The aim of this study was to evaluate the shear bond strength of composite resin in five different repair systems. Materials and methods. Sixty specimens (7 mm in diameter and 3 mm in height) of zirconia ceramic were fabricated. All specimen surfaces were prepared with a 30 µm fine diamond rotary cutting instrument with water irrigation for 10 s and dried with oil-free air. Specimens were then randomly divided into six groups for the following different intra-oral repair systems (n = 10): Group 1, control group; Group 2, Cojet system (3M ESPE, Seefeld, Germany); Group 3, Cimara® System (Voco, Cuxhaven, Germany); Group 4, Z-Prime Plus System (Bisco Inc., Schaumburg, IL); Group 5, Clearfil™ System (Kuraray, Osaka, Japan); and Group 6, Z-Bond System (Danville, CA). After surface conditioning, a composite resin Grandio (Voco, Cuxhaven, Germany) was applied to the zirconia surface using a cylindrical mold (5 mm in diameter and 3 mm in length) and incrementally filled up, according to the manufacturer’s instructions of each intra-oral system. Each specimen was subjected to a shear load at a crosshead speed of 1 mm/min until fracture. One-way analysis of variance (ANOVA) and Tukey post-hoc tests were used to analyze the bond strength values. Results. There were significant differences between Groups 2–6 and Group 1. The highest bond strength values were obtained with Group 2 (17.26 ± 3.22) and Group 3 (17.31 ± 3.62), while the lowest values were observed with Group 1 (8.96 ± 1.62) and Group 6 (12.85 ± 3.95). Conclusion. All repair systems tested increased the bond strength values between zirconia and composite resin that used surface grinding with a diamond bur.

Shear bond strength of a self-etched resin cement to an indirect composite: Effect of different surface treatments

OBJECTIVES The aim of this study was to compare the shear bond strength of resin cement (Rely X-U200) bonded to differently conditioned indirect composite samples. MATERIALS AND METHODS Sixty-six composite resin specimens (5 mm in diameter and 3 mm in thickness) were prepared with an indirect composite resin (Grandia) and randomly divided into six groups. Surfaces of the samples were treated with one of the following treatments; %37 phosphoric acid etching, sandblasting, 1,5 W, 2 W and 3 W erbium, chromium: Yttrium-scandium-gallium-garnet laser application. An untreated group was used as a control. In each group surface of the sample was analyzed with scanning electron microscopy. The remaining samples (n = 60) were built up with a self-adhesive resin cement (Rely X-U200) 3 mm in diameter and 2 mm height. After 24 h water storage at 37°C, the prepared specimens were submitted to shear bond strength test. One-way analysis of variance was used to analyze the bond strength values of different groups. RESULTS Highest shear bond strength values were observed in sandblasting group however there were not statistical difference among the tested surface treatment methods. CONCLUSION In Shear bond strength of resin, cement was independent of the surface conditioning methods applied on tested indirect resin composite.

Factors Associated with Knowledge and Attitude of Management of Traumatic Dental Injuries: A Cross-Sectional Study among Turkish Dentists

Objective: To evaluate the factors associated with knowledge and attitude of dentists regarding management of traumatic dental injuries (TDI). Material and Methods: In this cross-sectional and correlational study, the sample consisted of 136 Turkish dentists. A specialized questionnaire was developed and validated to collect data. The first part of the questionnaire included questions about sociodemographic characteristics, education level, working experince, working place, last dental trauma course, self-efficacy about management of TDI, and treatment frequency. The second part included a total of 17 questions with multiple choice and single correct answers regarding the management of intrusion and extrusion, avulsion, complicated crown fracture and crown-root fracture injuries in children. Descriptive statistics, multivariate analysis of variance, and partial eta squared coefficient ( 2 ) were used for statistical analysis. Results: There was a moderate level of knowledge among participants. The level of knowledge was statistically correlated (p 0.05). General dentists had lower self-efficacy than specialist dentists (p < 0.05). Conclusion: While Turkish dentists working in a province seem to have a moderate level of knowledge regarding treatment of different types of TDI, it is necessary to carry out necessary studies to improve the knowledge and raise self-efficacy.

Evaluation of Various Pretreatments to Fiber Post on the Push-out Bond Strength of Root Canal Dentin

Introduction: The aim of this in vitro study was to compare the effect of different pretreatments (fiber post) with the laser‐activated irrigation (LAI) technique (for removal of the smear layer) on root canal dentin in terms of push‐out bond strength (PBS) in a fiber post. Methods: Fifty freshly extracted mandibular single‐rooted premolars were prepared, and LAI was applied to all roots (17% EDTA was 5 mL for 120 seconds with an erbium, chromium:yttrium‐scandium‐gallium‐garnet laser [0.50 W, 20 Hz, 25 mJ]). In addition, 50 quartz fiber posts were randomly assigned to 5 groups (n = 10) according to the surface treatments as follows: group S (sandblasting), group N1 and group N2 (neodymium:yttrium‐aluminum‐garnet laser irradiation [2 W, 200 mJ, 10 Hz, with pulse durations of 180 or 320 microseconds), group HF (9.7% hydrofluoric acid etched), and group C (control with no treatment). Dual‐cure resin cement was adhered onto the fiber posts after they were covered with a silane agent, and then the posts were placed into the canal space using a Lentulo spiral. The PBS test was performed after all specimens were transversally sectioned (root slices of 1‐mm thickness). Data were analyzed with 1‐way analysis of variance/Tukey post hoc test (&agr; = 0.05). Results: The highest PBS value was observed in group S (middle part), and the lowest value was observed in group C (apical part). There were no statistical differences among the groups regardless of the part. Furthermore, when the PBS values of the different parts of dentin were compared within treated groups, significant differences were observed in all groups except group N2 (P < .05). Conclusions: Within the limitations of this study, it can be concluded that the LAI technique when used with 17% EDTA had a significant effect on the amount of smear layer removed from the root canal dentin, which was also detected in the fracture pattern (adhesive failure [resin‐post interface]). However, the various treatments of the fiber post did not improve the PBS of the root dentin. HighlightsIt is crucial to maximize the bond strength between the root dentin and resin and between the resin and fiber post for the success of post‐core restorations.EDTA + laser‐activated irrigation significantly reduces debris or smear layers from the root dentin wall.The mechanical treatments on the fiber post surfaces cannot affect the push‐out bond strength (PBS); however, other additional parameters must be evaluated.Studies on the effects of different surface treatments on the fiber post and root dentin walls together with PBS could enrich the literature.

Sivas İlindeki Okul Öncesi Yaş Grubu Çocukların Diş Sağlığı Durumlarının Değerlendirilmesi

Amac: Calismanin amaci, Sivas bolgesindeki okul oncesi yas grubundaki cocuklarda df(t) ve df(s) skorlarinin saptanarak, dis curugunun yasa ve cinsiyete gore dagiliminin degerlendirilmesidir. Gerec ve Yontem: Calismaya okul oncesi (3-6) doneminden uc, dort, bes ve alti yas olmak uzere 4 grup olusturacak sekilde toplam 1244 cocuk dahil edilmistir. Cocuklar okul ortaminda, dogal isik altinda ayna ve sond kullanilarak Dunya Saglik Orgutu’nun (WHO) kriterleri dogrultusunda muayene edilmislerdir. Bulgular formlara kaydedilmistir. Bulgular: Calismanin sonuclarina gore df(t) indeks degerleri 3 yas grubunda 1,63, 4 yas grubunda 2,72, 5 yas grubunda 3,04, 6 yas grubunda 3,64 olarak hesaplanmistir. Yaslara gore df(t) degerleri karsilastirildiginda farklilik onemli bulunmustur (p<0,05). Sonuc: Curuk prevelansi yas ile birlikte istatistiksel olarak anlamli oranda artmaktadir. Calismada edinilen sonuclar Dunya Saglik Orgutu tarafindan belirlenen hedeflerin henuz gerisindedir. Bu durum dikkate alinarak, agiz-dis hastaliklarini onlemeye yonelik olarak “Koruyucu Dis Hekimligi Hizmetleri”nin yayginlastirilmasi gerekmektedir.