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101.
Markus B Blatz Avishai Sadan John O Burgess Donald Mercante Stefan Hoist 《Quintessence international, dental digest》2005,36(2):97-104
OBJECTIVES: This study evaluated the ability of a new polyvinyl siloxane impression material (Affinis, Coltène/Whaledent, material A) to obtain final impressions free of bubbles and voids for indirect fixed cuspal-coverage restorations. The results were compared to a control polyvinyl siloxane impression material (material B). Both materials were handled by inexperienced clinicians (undergraduate dental students) in student clinics. METHOD AND MATERIALS: One-hundred and thirty patients who were treated in the Louisiana State University School of Dentistry Junior Student Clinic for indirect fixed cuspal-coverage restorations and who met the inclusion criteria were randomly assigned to either one of two treatment groups, group A (n = 65) or group B (n = 65). Two calibrated examiners evaluated the first impression of prepared posterior teeth at a magnification of 10x for acceptability (no voids or bubbles). Position of tooth, type of preparation, preparation finish line (Class I-V), and gingival bleeding scores were recorded. All statistical tests were performed with the level of significance set at .05. RESULTS: The Fisher-Freeman-Halton test did not reveal significant associations between material and gingival bleeding score (P = .492). Significant differences in the location of the preparation finish line between materials were observed (P = .0096); material A was more frequently used in cases where the preparation finish line was located at least 2 mm subgingivally. Logistic regression was used to assess the effect of the material on the success of the impression (acceptable/ unacceptable). Material was highly significant in the logistic model (P < .001) with an odds in favor of an acceptable impression being eight times higher with material A than with material B (odds ratio = 8.00; 95% confidence index for odds ratio: 2.832, 22.601). The 60/65 (92.3%) impressions made with material A and 39/65 (60%) impressions made with material B were rated "acceptable." CONCLUSION: The new polyvinyl siloxane impression material provided a significantly higher proportion of impressions free of bubbles and voids than the control polyvinyl siloxane material. 相似文献
102.
Kobayashi C Yaegaki K Calenic B Ishkitiev N Imai T Ii H Aoyama I Kobayashi H Izumi Y Haapasalo M 《Journal of endodontics》2011,37(4):479-484
Introduction
Untreated dental caries will eventually lead to pulpal inflammation. Although much is known regarding the interaction of microbial antigens and the immunologic defense systems of pulp, many aspects of the pathogenesis of pulpitis are not fully understood. The relationship between human pulp stem cells (HPSCs) and the pathogenesis of pulpitis remains among the poorly understood areas. Many of the invading bacteria are known to produce considerable amounts of hydrogen sulfide (H2S), which causes apoptosis in some tissues. The aims of this study were to determine whether H2S causes apoptosis in HPSCs and to examine its signaling pathway.Methods
Stem cells were isolated from human dental pulp and incubated with 50 ng/mL H2S for 48 hours. To detect apoptosis, the cells were analyzed by using flow cytometry. The mitochondrial signaling pathway was examined by determining mitochondrial membrane depolarization. Activation of the key apoptotic enzymes caspase-9, caspase-8, and caspase-3 was assessed by using enzyme-linked immunosorbent assay. Release of cytochrome C from mitochondria was also determined.Results
The number of apoptotic cells increased significantly with H2S treatment from 1.6% to 16.3% (P < .01). Significant increases were also measured in the amounts of caspase-9 and caspase-3 and in cytochrome C release (all P < .01) and in mitochondrial membrane depolarization (P < .05), whereas caspase-8 activity was not found.Conclusions
H2S causes apoptosis in HPSCs by activating the mitochondrial pathway. It is suggested that H2S might be one of the factors modifying the pathogenesis of pulpitis by causing loss of viability of HPSCs through apoptosis. 相似文献103.
Tseng William W. Swallow Carol J. Strauss Dirk C. Bonvalot Sylvie Rutkowski Piotr Ford Samuel J. Gonzalez Ricardo J. Gladdy Rebecca A. Gyorki David E. Fairweather Mark Lee Kyo Won Albertsmeier Markus van Houdt Winan J. Fau Magalie Nessim Carolyn Grignani Giovanni Cardona Kenneth Quagliuolo Vittorio Grignol Valerie Farma Jeffrey M. Pennacchioli Elisabetta Fiore Marco Hayes Andrew Tzanis Dimitri Skoczylas Jacek Almond Max L. Mullinax John E. Johnston Wendy Snow Hayden Haas Rick L. Callegaro Dario Smith Myles J. Bouhadiba Toufik Desai Anant Voss Rachel Sanfilippo Roberta Jones Robin L. Baldini Elizabeth H. Wagner Andrew J. Catton Charles N. Stacchiotti Silvia Thway Khin Roland Christina L. Raut Chandrajit P. Gronchi Alessandro 《Annals of surgical oncology》2022,29(12):7335-7348
Annals of Surgical Oncology - Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly... 相似文献
104.
Hagen Loertzer Tanja Huesch Ruth Kirschner-Hermanns Ralf Anding Armin Rose Bernhard Brehmer Carsten Maik Naumann Fabian Queissert Joanne Nyarangi-Dix Roland Homberg Markus Grabbert Torben Hofmann Tobias Pottek Wilhelm Hübner Axel Haferkamp Ricarda Michaela Bauer Alexander Kretschmer 《Neurourology and urodynamics》2020,39(3):987-993
105.
106.
107.
Marcus Raudner MD Markus M. Schreiner MD Michael Weber Mag. Dr. Vladimir Juras PhD David Stelzeneder MD Reinhard Windhager Prof. MD Siegfried Trattnig Prof. MD 《Journal of orthopaedic research》2020,38(9):2057-2064
The aim of this study was to assess T2 values of the lumbar intervertebral discs in the axial and sagittal plane views and assess their respective interobserver reliability. The lumbar intervertebral discs of 23 symptomatic patients (11 female; 12 male; mean age, 44.1 ± 10.6; range, 24-64 years) were examined at 3T. Region-of-interest (ROI) analysis was performed on axial and sagittal T2 maps by two independent observers. Intraclass correlation coefficient (ICC) was assessed for every ROI. The interobserver agreement was excellent for the nucleus pulposus (NP) in the sagittal (0.951; 95% confidence interval [CI], 0.926-0.968) and axial (0.921; 95% CI, 0.845-0.955) planes. The posterior 20% region showed a higher ICC in the axial vs the sagittal assessment (0.845; 95% CI, 0.704-0.911 vs 0.819; 95% CI, 0.744-0.873). The same was true for the posterior 10%, with the axial ROI showing a higher ICC (0.923; 95% CI, 0.865-0.953 vs 0.628; 95% CI, 0.495-0.732). The intraobserver agreement was excellent for every ROI except the sagittal 10% region, which showed good performance (0.869; 95% CI, 0.813-0.909). The sagittal nucleus pulposus was the best-performing ROI with regard to intra- and interobserver agreement in the T2 assessment of the lumbar intervertebral disc. However, the axial NP showed more stable agreements overall and across the value range. In addition, the annular analysis showed better inter- and intraobserver agreement in the axial plane view. Clinical significance: Based on the presented analysis, we highly recommend that further studies use axial T2 mapping due to the higher intra- and interreader agreement. 相似文献
108.
109.
Mannion Anne F. Mariaux Francine Reitmeir Raluca Fekete Tamas F. Haschtmann Daniel Loibl Markus Jeszenszky Dezsö Kleinstück Frank S. Porchet François Elfering Achim 《European spine journal》2020,29(8):1935-1952
European Spine Journal - Depression, anxiety, catastrophising, and fear-avoidance beliefs are key "yellow flags" (YFs) that predict a poor outcome in back patients. Most surgeons... 相似文献
110.