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 manufacturer's 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 study's 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.
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.
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.
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.
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.
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.
The aim of this study was to compare the effects of 2 NiTi file systems Twisted File Adaptive (TFA) and Reciproc (RP) and 2 irrigation techniques Conventional needle irrigation (CNI) and Laser ...activated irrigation (LAI) on the amount of apically extruded debris in primary maxillary molars.
Sixty extracted primary maxillary molars were randomly divided into 4 groups. The mesio-buccal roots of teeth in 4 groups were instrumented using TFA with LAI, RP with LAI, TFA with CNI and RP with CNI respectively. Debris extruded during instrumentation was collected into Eppendorf tubes and amounts were determined. The data were analyzed using two-way ANOVA test at 0.05 level of significance.
The results indicated all instrumentation and irrigation systems caused a measurable apical extrusion of debris. However, no statistically significant difference in debris extrusion was observed between irrigation techniques or instrumentation systems (P > 0.05). The total amount of debris extruded apically by LAI was greater than that by CNI.
All instrumentation and irrigation techniques caused debris extrusion. However, the optimal laser activation time and power settings should be investigated to ensure minimal extrusion of debris and irrigant due to cavitation and pressure during LAI in root canal treatment.
Additive manufacturing (AM), also known as 3D printing, has the potential to transform the industry. While there have been advancements in using AM for dental restorations, there is still a need for ...further research to develop functional biomedical and dental materials. It’s crucial to understand the current status of AM technology and research trends to advance dental research in this field. The aim of this study is to reveal the current status of international scientific publications in the field of dental research related to AM technologies.
In this study, a systematic scoping review was conducted using appropriate keywords within the scope of international scientific publishing databases (PubMed and Web of Science). The review included related clinical and laboratory research, including both human and animal studies, case reports, review articles, and questionnaire studies. A total of 187 research studies were evaluated for quantitative synthesis in this review.
The findings highlighted a rising trend in research numbers over the years (From 2012 to 2022). The most publications were produced in 2020 and 2021, with annual percentage increases of 25.7% and 26.2%, respectively. The majority of AM-related publications in dentistry research originate from Korea. The pioneer dental sub-fields with the ost publications in its category are prosthodontics and implantology, respectively.
The final review result clearly stated an expectation for the future that the research in dentistry would concentrate on AM technologies in order to increase the new product and process development in dental materials, tools, implants and new generation modelling strategy related to AM. The results of this work can be used as indicators of trends related to AM research in dentistry and/or as prospects for future publication expectations in this field.
Abstract Introduction To evaluate the effectiveness of QMix solution (Dentsply Tulsa Dental Specialties, Tulsa, OK) on the smear layer using the following irrigation activation techniques: the ...EndoActivator (EA) system (Dentsply Tulsa Dental Specialties), photon-initiated photoacoustic streaming (PIPS), and an Er:YAG laser with an endodontic fiber tip. Methods Sixty-four extracted single-rooted human teeth were decoronated and the canals instrumented with ProTaper (Denstply Maillefer, Ballagues, Switzerland) up to size F4. The canals were irrigated with 5.25% sodium hypochlorite and a saline solution for 1 minute each. The specimens were then divided randomly into 4 experimental and 4 control groups ( n = 8) according to the final irrigation activation technique. These groups included group 1, 2.5 mL QMix; group 2, QMix + EA; group 3, QMix + PIPS; and group 4: QMix + Er:YAG. Laser activated distilled water was used as control groups 5, 6, 7, and 8. Teeth were split longitudinally, and specimens were observed under a scanning electron microscope. Images were taken at the coronal, middle, and apical thirds of the teeth at a magnification of 1000× and were scored in the presence of the smear layer. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Results The highest scores were found in the apical third of all groups ( P < .05). The QMix + Er:YAG group removed the smear layer more effectively than the nonactivated QMix group in the apical third ( P < .05). The QMix + EA group removed the smear layer significantly in all thirds of the teeth when compared with the nonactivated QMix group ( P < .05). The QMix + PIPS group showed a significantly better effect than the QMix group in the coronal third ( P < .05). Conclusions The EA and Er:YAG laser enhanced the smear layer removal ability of QMix in the apical thirds of the canals. QMix removed more smear layer in the coronal thirds when activated with the PIPS technique.
INTRODUCTIONThis study aimed to compare the accuracy of cone-beam computed tomographic (CBCT) scanning and 2 different electronic apex locators (EALs) in the detection of simulated root canal ...perforations in different localizations.METHODSEighty human mandibular premolars were prepared and divided into 2 groups according to the localization of the perforation area, having a 1-mm diameter. The distance between the occlusal edge and the beginning of the perforation was measured under a stereomicroscope (actual working length) using 2 EALs (Propex II Dentsply Maillefer, Ballaigues, Switzerland and Dentaport ZX J. Morita, Tokyo, Japan) (electronic working length) and CBCT images (CBCT working length). The calculations were made by subtracting the actual working length from the electronic working length and the CBCT working length to determine the differences.RESULTSIn the apical third perforation group, there was a significant difference between Dentaport ZX and CBCT imaging. There was no significant difference between Dentaport ZX and Propex II and Propex II and CBCT measurements. In the middle third perforation group, Propex II was significantly more successful than CBCT imaging. In addition, there was no significance between the accuracy of Propex II in detecting the perforation area between the apical third perforation group and the middle third perforation group. CBCT imaging was more accurate in detecting the perforation area in the apical third perforation group than in the middle third perforation group.CONCLUSIONSIn cases in which the root canal perforation was in the apical third of the root, both the EAL and CBCT imaging were successful in determining the perforation area, whereas the success rate of all devices used in this study decreased when the perforation area was in the middle third of the root.
Objective:The objective of this study was to evaluate the antimicrobial activity of different power settings of potassium-titanyl-phosphate (KTP) laser in experimentally infected root ...canals.Methods:A total of 119 freshly extracted human single-rooted teeth with mature apices were selected for study. After preparation and sterilization, the specimens were inoculated with 15 µL Enterococcus faecalis for 24 hours at 37°C. The contaminated roots were divided into five experimental groups (1W, 1.5W, 2W, 3W, and 4W KTP laser), one negative control sodium hypoclorite (NaOCl) group, and one positive control sterile saline (SF) group of 17 teeth each. Before and after applications in the groups, samples retrieved with sterile paper points from the root canal were transferred to tubes containing 5 mL of the brain heart infusion broth. Next, 10 μL of these suspensions were placed at two different sides of the blood agar medium. Bacterial reduction was counted according to the colony-forming units and data were statistically analyzed using the Kruskal–Wallis and Tukey’s tests.Results:The maximum decrease occurred in the 2.5% NaOCl (100%±0.00%) group. This decrease was followed by decreases in the following KTP laser groups: 4W (94.26%), 3W (87.98%), 2W (77.43%), SF (68.80%), 1.5W (65.89%), and 1W (52.08%). Statistically, the difference between the 1W KTP laser group and all groups and the difference between the 2.5% NaOCl group and all groups, except the 4W KTP laser group, were found to be significant (p<0.05).Conclusion:High-power KTP laser irradiation showed efficient antibacterial activity against E. faecalis.
Purpose: To investigate the influence of various nickel-titanium (Ni-Ti) files on debris extrusion during the retreatment of teeth with simulated lateral root perforation, focusing on root ...resorption.Methods: Sixty human mandibular premolar teeth were divided into groups with and without perforation and further subdivided based on the retreatment technique. Lateral root perforations were created in one group (Group 1), while the other group had no perforations (Group 2). Two retreatment techniques were compared: Remover (RE)+One RECI (OR) and ProTaper Universal Retreatment (PTUR)+WaveOne Gold (WOG). The weight of the extruded debris was determined. The time of both retreatment procedures was measured. Statistical analyses were performed using a two-way analysis of variance (ANOVA) test (P < 0.05).Results: Teeth with simulated lateral root perforation exhibited higher extrusion of debris during retreatment. In both groups, RE+OR files led to more extruded debris than PTUR+WOG files. However, this difference was statistically significant in Group 2 (P < 0.001). Compared to PTUR+WOG files, RE+OR files showed a statistically significant longer time to remove obturation material (P < 0.001).Conclusion: Perforated teeth exhibited significantly higher debris extrusion. While both file systems demonstrated similar debris extrusion in perforated teeth, the RE+OR files significantly increased debris extrusion in non-perforated teeth compared to the PTUR+WOG files.
This study compared the effects of 3 different cavity disinfection protocols (CDP) on the shear bond strength (SBS) of resin‐modified glass ionomer cement (RM‐GIC) to mineral trioxide aggregate ...(MTA). One hundred eighty standard holes were prepared and filled with MTA. They then divided into 3 main groups based on the chosen time intervals (15 min, 24 h, and 72 h). Main groups were divided into 3 subgroups based on the CDP chlorhexidine gluconate (CHX), ozone, laser, and control. RM‐GIC was applied on MTA after CDP for all groups. A universal testing device was then used for test and the data was statistically analysed. CHX showed significantly lower SBS values except ozone and laser than the control (p < 0.05). There were no statistically significant differences among the time intervals. As a result, CHX decreased the bond strength between the MTA and RM‐GIC while ozone and laser had no negative effect.
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