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WOS: 000354606800010, PubMed ID: 25330165, 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 32x 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.

WOS: 000340846900007, PubMed ID: 25102408, Objective: The purpose of this study was to investigate the effects of various surface pretreatments in the ridge lap area of acrylic resin denture teeth on the shear bond strength to heat-polymerized polymethylmethacrylate (PMMA) denture base resin. Background data: Tooth debonding of the denture is a major problem for patients with removable prostheses. Methods: A total of 84 central incisor denture teeth were used in this study. Seven test groups with 12 specimens for each group were prepared as follows: untreated (control, group C), ground, with a tungsten carbide bur (group H), airborne-particle abrasion (group AA), primed with methyl methacrylate (group M), treated with izobutyl methacrylate (group iBMA), Eclipse Bonding Agent applied (group E), and Er:YAG laser irradiated (group L). Test specimens were produced according to the manufacturers' instructions and mounted to a universal testing machine for shear testing with a crosshead speed of 1 mm/min. Data were evaluated by one way variance analysis (ANOVA) and Tukey's test (alpha = 0.05). Results: Similar bond strength values were found between groups L and M, and these were the highest shear bond strengths among the groups. The lowest one was observed in group E. All surface treatments, except group E, exhibited significant difference when compared with group C (p < 0.05). Conclusions: Lasing of the ridge lap area to enhance the bond strength of acrylic resin denture teeth to PMMA denture base resin might be an alternative to wetting with MMA monomer. To overcome tooth debonding, surface treatment of the ridge lap area should be performed as part of denture fabrication.

WOS: 000344330400064, PubMed ID: 25139129, Purpose. Debonding at the post-adhesive interface is a major problem for quartz fiber posts. The objective of this study was to evaluate surface roughness and bond strength of quartz fiber posts after various surface treatments. Materials and methods. Sixty-six quartz fiber posts were randomly divided into six experimental groups (n = 11) including group C, untreated (control); group SB, sandblasted; group SC, silica coated; group HF, hydrofluoric acid-etched; group N, Nd:YAG laser irradiated; group E, Er:YAG laser irradiated. Surface roughness of the posts was measured before and after pre-treatment. They were then bonded to resin cement and tensile bond strength was determined in a universal testing machine. Furthermore, two-way ANOVA and post hoc comparison tests (alpha = 0.05) were performed on all data. Results. The highest mean force value was observed in group SB and followed by group E. Tukey's HSD test showed that there was no statistical difference between group SB and group E (p = 0.673). The highest mean roughness value was observed in group SB and a significant difference was found between group SB and all other groups (p < 0.001). This study reveals that sandblasting and Er:YAG laser irradiation provided a significant increase in bond strength between quartz fiber posts and resin cement. Conclusions. Sandblasting or Er:YAG laser-irradiation of the surface of the quartz fiber post before cementation is recommended for increasing retention., Cumhuriyet University Scientific Research Project, This investigation was supported by the Cumhuriyet University Scientific Research Project. This study was presented in a poster at the annual meeting of the 19th Aegean Region Chambers of Dentists International Scientific Congress and Exhibition, 26-28 April, 2012, Fethiye, Turkey.

WOS: 000340259700006, PubMed ID: 24255966, 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, mu m) 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 Tukey's 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.

WOS: 000319978500005, PubMed ID: 23741995, Objective: The aim of this study was to evaluate the effect of different surface treatments: sandblasting, liners, and different laser irradiations on shear bond strength (SBS) of pre-sintered zirconia to veneer ceramic. Background data: The SBS between veneering porcelain and zirconium oxide (ZrO2) substructure was weak. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to veneering porcelain. There is no study that evaluated the bond strength between veneering porcelain and the different surface treatments on pre-sintered ZrO2 substructure. Methods: Two hundred specimens with 7mm diameter and 3mm height pre-sintered zirconia blocks were fabricated. Specimens were randomly divided into 10 groups (n = 20) according to surface treatments applied. Group C, untreated (Control); Group E, erbium: yttrium-aluminum-garnet (Er:YAG) laser irradiated; Group N, neodymium: yttrium-aluminum-garnet (Nd:YAG) laser irradiated; Group SB, sandblasted; Group L, liner applied; Group NL, Nd:YAG laser irradiated + liner applied; Group EL, Er:YAG laser irradiated + liner applied; Group SN, sandblasted + Nd:YAG laser irradiated; Group SE, sandblasted + Er:YAG laser irradiated; and Group SL, sandblasted + liner applied. The disks were then veneered with veneering porcelain. Before the experiment, specimens were steeped in 37 degrees C distilled water for 24 h. All specimens were thermocycled for 5000 cycles between 5 degrees C and 55 degrees C with a 30 sec dwell time. Shear bond strength test was performed at acrosshead speed of 1 mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern. Results: Surface treatments significantly changing the topography of the yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic according to scanning electron microscopic (SEM) images. The highest mean bond strength value was obtained in Group SE, and the lowest bond strength value was observed in NL group. Bond strength values of the other groups were similar to each other. Conclusions: This study shows that sandblasting + Er:YAG, sandblasting, Er:YAG + liner, sandblasting + Nd:YAG, and Er:YAG laser treatment on pre-sintered ZrO2 substructure increased the bond strength to veneering porcelain, compared with other surface treatments. After different surface treatments, there was no difference in surface roughness of pre-sintered zirconia to compare after sintering; sintering enhanced the bond strength within the limitations of present study.

WOS: 000313096400017, PubMed ID: 22447403, This study evaluated the effect of various surface treatments on the tensile bond strength of a silicone-based soft denture liner to two chemically different denture base resins, heat-cured polymethyl methacrylate (PMMA), and light-activated urethane dimethacrylate or Eclipse denture base resin. PMMA test specimens were fabricated and relined with a silicone-based soft denture liner (group AC). Eclipse test specimens were prepared according to the manufacturer's recommendation. Before they were relined with a silicone-based soft denture liner, each received one of three surface treatments: untreated (control, group EC), Eclipse bonding agent applied (group EB), and laser-irradiated (group EL). Tensile bond strength tests (crosshead speed = 5 mm/min) were performed for all specimens, and the results were analyzed using the analysis of variance followed by Tukey's test (p = 0.05). Eclipse denture base and PMMA resins presented similar bond strengths to the silicone-based soft denture liner. The highest mean force was observed in group EL specimens, and the tensile bond strengths in group EL were significantly different (p < 0.05) from those in the other groups.

WOS: 000298152400006, PubMed ID: 22150095, Objective:The aim of this study was to evaluate the effect of different surface treatments; sandblasting, Er:YAG, Nd:YAG, or CO2 laser irradiation on the shear bond strength (SBS) of zirconia ceramic to dentin. Background data:Zirconia is not properly luted with resin cements. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to resin cements. There is no study that compared the effect of different laser types (Er:YAG, Nd:YAG, CO2) with sandblasting on SBS between zirconia and dentin. Methods:One hundred and twenty human maxillary third molar teeth were sectioned 3mm below the occlusal surfaces, embedded in a metal ring with autopolymerizing acrylic resin, and stored in distilled water at 37(0)C. One hundred and twenty disc-shaped zirconia specimens were fabricated (6mm in diameter and 4mm in thickness), and randomly assigned to six groups (n = 20):Group 1, untreated (control); Group 2, sandblasted; Group 3, Er:YAG laser irradiated; Group 4, Nd:YAG laser irradiated with contact; Group 5, Nd:YAG laser irradiated with non-contact; Group 6, CO2 laser irradiated. They were cemented onto the dentin with dual-cured resin cement (Variolink (R)). After they were stored in distilled water at 37(0)C for 24 h, the SBS test was performed at a crosshead speed of 1mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern. Results:Results of this study did not show statistically significant differences between Groups 1 and 2, or among Groups 3, 4 and 5. The lowest SBS was recorded in Group 6 (CO2 laser), and the highest SBS was recorded in Group 4 (Nd:YAG laser with contact), followed by Group 3 (Er:YAG laser). The adhesive failure mode was predominantly observed in Groups 2, 3, 5, and 6. Group 1 showed 45% mixed failure and Group 4 showed 50% mixed failure. Conclusions:This study shows that Er:YAG and Nd:YAG laser treatment increased the bond strength of zirconia compared to sandbasting and CO2 laser treatment.

WOS: 000348177500004, PubMed ID: 25555090, 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

WOS: 000351753800019, PubMed ID: 25772927, 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 degrees 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.