PURPOSE: This study aimed to evaluate the effect of pretreatment of three different universal adhesives (Single Bond Universal [SBU], All-Bond Universal [ABU], and Prime&Bond universal [PBU]) on the bonding durability of an adhesive (Panavia F 2.0, PF) and a conventional (Duo-Link, DL) resin cements to air-abraded zirconia. MATERIALS AND METHODS: Rectangular-shaped zirconia specimens were prepared. The chemical composition and surface energy parameters of the materials were studied by Fourier transform infrared spectroscopy and contact angle measurement, respectively. To evaluate resin bonding to the zirconia, all the bonding specimens were immersed in water for 24 h and the specimens to be aged were additionally thermocycled 10000 times before the shear bond strength (SBS) test. RESULTS: The materials showed different surface energy parameters, including the degree of hydrophilicity/hydrophobicity. While the DL/CON (no pretreatment) showed the lowest SBS and a significant decrease in the value after thermocycling (P < .001), the PF/CON obtained a higher SBS value than the DL/CON (P < .001) and no decrease even after thermocycling (P = .839). When the universal adhesives were used with DL, their SBS values were higher than the CON (P < .05), but the trend was adhesive-specific. In conjunction with PF, the PF/SBU produced the highest SBS followed by the PF/ABU (P = .002), showing no significant decrease after thermocycling (P > .05). The initial SBS of the PF/PBU was similar to the PF/CON (P = .999), but the value decreased after thermocycling (P < .001). CONCLUSION The universal adhesive pretreatment did not necessarily show a synergistic effect on the bonding performance of an adhesive resin cement, whereas the pretreatment was beneficial to bond strength and durability of a conventional resin cement.

Background: In addition to vascular endothelial cells, vascular smooth muscle cells (VSMCs) are subject to continuous shear stress because of blood circulation. The angiogenic properties of VSMCs in extracranial arteriovenous malformations (AVMs) may exceed those of normal blood vessels if the body responds more sensitively to mechanical stimuli. This study was performed to investigate the hypothesis that rapid angiogenesis may be achieved by mechanical shear stress. Methods: VSMCs were obtained from six patients who had AVMs and six normal controls. The target genes were set to angiopoietin-2 (AGP2), aquaporin-1 (AQP1), and transforming growth factor-beta receptor 1 (TGFBR1). Reverse-transcriptase polymerase chain reaction (RT-PCR) and real-time PCR were implemented to identify the expression levels for target genes. Immunofluorescence was also conducted. Results: Under the shear stress condition, mean relative quantity values of AGP2, AQP1, and TGFBR1 in AVM tissues were 1.927±0.528, 1.291±0.031, and 2.284±1.461 when compared with neutral conditions. The expression levels of all three genes in AVMs were higher than those in normal tissue except for AQP1 under shear stress conditions. Immunofluorescence also revealed increased staining of shear stress-induced genes in the normal tissue and in AVM tissue. Conclusions Shear stress made the VSMCs of AVMs more sensitive. Although the pathogenesis of AVMs remains unclear, our study showed that biomechanical stimulation imposed by shear stress may aggravate angiogenesis in AVMs.

Very virulent infectious bursal disease virus (vvIBDV) causes high mortality in chickens but measures to reduce the mortality have not been explored. Chickens (8–9 weeks) were treated with 3 agents before and during vvIBDV inoculation. Dexamethasone treatment reduced the mortality of infected chickens (40.7% vs. 3.7%; p < 0.001), but treatment with aspirin or vitamin E plus selenium did not affect the mortality. The bursa of Fabricius appeared to have shrunk in both dead and surviving chickens (p < 0.01). The results indicate that dexamethasone can reduce mortality in vvIBDV-infected chickens and may provide therapeutic clues for saving individual birds infected by the virus.

Very virulent infectious bursal disease virus (vvIBDV) causes high mortality in chickens but measures to reduce the mortality have not been explored. Chickens (8–9 weeks) were treated with 3 agents before and during vvIBDV inoculation. Dexamethasone treatment reduced the mortality of infected chickens (40.7% vs. 3.7%; p < 0.001), but treatment with aspirin or vitamin E plus selenium did not affect the mortality. The bursa of Fabricius appeared to have shrunk in both dead and surviving chickens (p < 0.01). The results indicate that dexamethasone can reduce mortality in vvIBDV-infected chickens and may provide therapeutic clues for saving individual birds infected by the virus.

This study aimed to investigate whether pre-curing the universal adhesives affect the resin bonding to zirconia ceramic. Two commercial universal adhesives (All-Bond Universal, ABU; Single Bond Universal Adhesive, SBU) were tested in comparison with a conventional zirconia primer (Z-Prime Plus, ZPP). Air-abraded zirconia specimens were divided into six groups, to which different priming agents were applied with or without photo-polymerization. After resin cylinders were built on the primed zirconia surface using a resin cement (Duo-Link), all bonded specimens were stored in water at 37℃ for 24 hours and half of them (n = 12) were additionally thermocycled 5,000 times. A shear bond strength test was performed at a crosshead speed of 0.5 mm/minute and failure modes were assessed using an optical microscope at 25× magnification. Before thermocycling, the light-cured specimens of ABU and SBU showed higher bond strengths than the uncured ones of the materials (p<0.05), whereas no significant difference was found between the pre-cured and uncured specimens of ZPP (p > 0.05). After thermal aging, there were significant decreases in the bond strength for all specimens treated with the universal adhesives (p<0.05). However, ZPP produced no significant difference after aging (p > 0.05) and attained higher bond strength values for both the pre-cured and uncured specimens when compared to the two universal adhesives (p<0.05). Adhesive failures were predominant in all test groups and thermocycling resulted in the higher incidences of adhesive failures for the uncured groups, which was not shown in the pre-cured groups.
Adhesives ; Aging ; Ceramics ; Incidence ; Resin Cements ; Water

PURPOSE: The present study was designed to examine the clinical fit of fixed dental prosthesis fabricated by the milling-sintering method using a presintered cobalt-chromium alloy. MATERIALS AND METHODS: Two single metal-ceramic crowns were fabricated via milling-sintering method and casting method in each of the twelve consecutive patients who required an implant-supported fixed prosthesis. In the milling-sintering method, the prosthetic coping was designed in computer software, and the design was converted to a non-precious alloy coping using milling and post-sintering process. In the casting method, the conventional manual fabrication process was applied. The absolute marginal discrepancy of the prostheses was evaluated intraorally using the triple-scan technique. Statistical analysis was conducted using Mann-Whitney U test (α=.05). RESULTS: Eight patients (66.7%) showed a lower marginal discrepancy of the prostheses made using the milling-sintering method than that of the prosthesis made by the casting method. Statistically, the misfit of the prosthesis fabricated using the milling-sintering method was not significantly different from that fabricated using the casting method (P=.782). There was no tendency between the amount of marginal discrepancy and the measurement point. CONCLUSION: The overall marginal fit of prosthesis fabricated by milling-sintering using a presintered alloy was comparable to that of the prosthesis fabricated by the conventional casting method in clinical use.
Alloys ; Clinical Study ; Crowns ; Dental Prosthesis ; Humans ; Methods ; Prostheses and Implants

The purpose of this study was to compare the accuracy of the working models fabricated by the subtractive and additive processing methods based on the 3-dimensional reconstruction model. A total of 20 models were fabricated with subtractive processing method from polymethyl methacrylate (PMMA) blocks using the stereolithography (STL) file of master gypsum model and another 20 models were fabricated with additive processing method using 3D printer with 0.025 mm of a layer thickness. The CAD-reference-model (CRM) and CAD-test-model (CTM) were superimposed by a software for accuracy analysis (Geomagic Qualify 13), where the STL files were transformed to point cloud data and the surface data (CRM and CTM) were subjected to initial alignment and followed by re-alignmented according to best-fit superimposition. The distances between surface data and all points, in this process, were converted to the root mean square (RMS) and averaged. In the experimental results, It was shown that the accuracy is higher in work model fabricated by additive processing method compared to one fabricated by subtractive one (p < 0.05). In addition, it is considered that the working model fabricated by subtractive processing method is to be clinically applicable by improving the improper reproducibility of the tooth surface and depressed area.
Calcium Sulfate ; Methods ; Polymethyl Methacrylate ; Printing, Three-Dimensional ; Tooth

PURPOSE: To assess the usefulness of an ultrasound (US)-guided peritoneal biopsy for the solitary peritoneal thickening visualized as only infiltrated fat on a computed tomography (CT) scan. MATERIALS AND METHODS: This retrospective study included 36 patients (16 males, 20 females; mean age, 51.7 years) who underwent a US-guided biopsy for the solitary peritoneal thickening of unknown cause visualized as only infiltrated fat without an apparent mass formation on a CT scan. The rate of the specific histopathological diagnosis and accuracy for the diagnosis of malignant disease was assessed. RESULTS: The procedure was technically successful with the acquisition of an adequate amount of the specimen for microscopic examination from all patients. A specific histopathological diagnosis was made in 31/36 patients (86.1%): peritoneal carcinomatosis in 15/31 (48.4%), tuberculous peritonitis in 15/31 (48.4%) and panniculitis in 1/31 (3.2%). A non-specific histopathological diagnosis was made in 5/36 (13.9%): chronic inflammation in 4/5 (80%) and mesothelial hyperplasia in 1/5 (20%). The procedure showed sensitivity of 83.3%, with a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 85.7%, and an accuracy rate of 86.1% for the diagnosis of malignant diseases. CONCLUSION The US-guided peritoneal biopsy is a fairly accurate diagnostic procedure for the peritoneal thickening visualized as only infiltrated fat on a CT scan, and it can be used before performing laparoscopic or an open biopsy.

OBJECTIVES: Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. MATERIALS AND METHODS: Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). RESULTS: Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. CONCLUSIONS: The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.
Bacterial Adhesion ; Composite Resins ; Flow Cytometry ; Fungi ; In Vitro Techniques* ; Streptococcus mutans* ; Streptococcus* ; Surface Properties ; Water

OBJECTIVES: To determine the optimal timing for post space preparation of root canals sealed with epoxy resin-based AH Plus sealer in terms of its polymerization and influence on apical leakage. MATERIALS AND METHODS: The epoxy polymerization of AH Plus (Dentsply DeTrey) as a function of time after mixing (8, 24, and 72 hours, and 1 week) was evaluated using Fourier transform infrared (FTIR) spectroscopy and microhardness measurements. The change in the glass transition temperature (Tg ) of the material with time was also investigated using differential scanning calorimetry (DSC). Fifty extracted human single-rooted premolars were filled with gutta-percha and AH Plus, and randomly separated into five groups (n = 10) based on post space preparation timing (immediately after root canal obturation and 8, 24, and 72 hours, and 1 week after root canal obturation). The extent of apical leakage (mm) of the five groups was compared using a dye leakage test. Each dataset was statistically analyzed by one-way analysis of variance and Tukey's post hoc test (α = 0.05). RESULTS: Continuous epoxy polymerization of the material with time was observed. Although the T(g) values of the material gradually increased with time, the specimens presented no clear T(g) value at 1 week after mixing. When the post space was prepared 1 week after root canal obturation, the leakage was significantly higher than in the other groups (p < 0.05), among which there was no significant difference in leakage. CONCLUSIONS: Poor apical seal was detected when post space preparation was delayed until 1 week after root canal obturation.
Bicuspid ; Calorimetry, Differential Scanning ; Dataset ; Dental Pulp Cavity* ; Fourier Analysis ; Glass ; Gutta-Percha ; Humans ; Polymerization ; Polymers ; Post and Core Technique ; Root Canal Obturation ; Root Canal Preparation ; Spectrum Analysis ; Transition Temperature