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排序方式: 共有2180条查询结果,搜索用时 15 毫秒
1.
George Haddad Malte Klling Urs A. Wegmann Angela Dettling Harald Seeger Roland Schmitt Inga Soerensen-Zender Hermann Haller Andreas D. Kistler Anne Dueck Stefan Engelhardt Thomas Thum Thomas F. Mueller Rudolf P. Wüthrich Johan M. Lorenzen 《Journal of the American Society of Nephrology : JASN》2021,32(2):323
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3.
Minini Andrea Raes Matthias Taccone Fabio S. Malbrain Manu L. N. G. 《Journal of clinical monitoring and computing》2021,35(4):681-687
Journal of Clinical Monitoring and Computing - 相似文献
4.
Braut V Bornstein MM Belser U Buser D 《The International journal of periodontics & restorative dentistry》2011,31(2):125-131
The purpose of this retrospective radiographic study was to analyze the thickness of the facial bone wall at teeth in the anterior maxilla based on cone beam computed tomography (CBCT) images, since this anatomical structure is important for the selection of an appropriate treatment approach in patients undergoing postextraction implant placement. A total of 125 CBCT scans met the inclusion criteria, resulting in a sample size of 498 teeth. The thickness of the facial bone wall in the respective sagittal scans was measured perpendicular to the long axis of the tooth at two locations: at the crest level (4 mm apical to the cementoenamel junction; MP1) and at the middle of the root (MP2). No existing bone wall was found in 25.7% of all teeth at MP1 and in 10.0% at MP2. The majority of the examined teeth exhibited a thin facial bone wall (< 1 mm; 62.9% at MP1, 80.1% at MP2). A thick bone wall (? 1 mm) was found in only 11.4% of all examined teeth at MP1 and 9.8% at MP2. There was a statistically significant decrease in facial bone wall thickness from the first premolars to the central incisors. The facial bone wall in the crestal area of teeth in the anterior maxilla was either missing or thin in roughly 90.0% of patients. Both a missing and thin facial wall require simultaneous contour augmentation at implant placement because of the well-documented bone resorption that occurs at a thin facial bone wall following tooth extraction. Consequently, radiographic analysis of the facial bone wall using CBCT prior to extraction is recommended for selection of the appropriate treatment approach. 相似文献
5.
Short-Term Results of IPS-Empress Inlays and Onlays 总被引:1,自引:0,他引:1
Stephan Studer DMD Christian Lehner DMD Urs Brodbeck DMD Peter Schärer DMD MS 《Journal of prosthodontics》1996,5(4):277-287
Purpose A leucite-reinforced, glass-ceramic material was recently introduced for clinical use. In this clinical trial, IPS-Empress inlays and onlays were evaluated using the modified United States Public Health Service (USPHS) criteria. Materials and Methods The teeth of 36 patients were restored with 105 posterior inlays and 25 onlays, fabricated by an indirect technique. After etching the restorations with hydrofluoric acid, they were silanized and luted using composite cements. The restorations were evaluated visually, clinically with a mirror and probe, and by bitewing radiographs and clinical photographs, using modified USPHS criteria. Restorations having neither charlie nor delta criteria were defined as successful, and their survival rate was calculated according to Kaplan-Meier analysis. Results The mean observation period for the 130 restorations was 23.4 ± 6.1 months. After 2 years, 127 restorations were successful with an estimated survival rate of 97.5%. Three restorations failed because of fractures. The esthetic results were excellent. Conclusions The initial clinical results of this esthetic restorative material are encouraging. However, because of fatigue phenomena for all ceramic materials, a longer observation period is needed to provide a definitive prognosis of the long-term clinical behavior. 相似文献
6.
AIM: The aim of this 10-year study (observation time 8-12 years, mean: 10 years) was to compare the survival rates, success rates and incidences of biological complications using three different implant designs of the ITI Dental Implant System. MATERIAL AND METHODS: In 89 dental patients treated comprehensively, a total of 112 hollow screw (HS), 49 hollow cylinder (HC) and 18 angulated hollow cylinder (AHC) implants were installed depending on the available bone volume and according to prosthetic needs. One and 10 years after surgical placement, clinical and radiographic parameters were assessed. The incidences of peri-implantitis according to various thresholds were registered over 10 years of maintenance. RESULTS: Success criteria at 10 years were set at: pocket probing depth (PPD)< or =5 mm, bleeding on probing (BoP)-, bone loss < 0.2 mm annually. The survival rate for HS was 95.4%, for HC 85.7% and for AHC 91.7%. Ninety percent of all the HS, 71% of the HC and 88% of the AHC did not present with an incidence of peri-implantitis over the 10 years, HC having significantly higher incidence of peri-implantitis than HS (P< 0.004). With the success criteria set above, a success rate for HS of 74%, for HC of 63% and for AHC of 61% was identified at 10 years. However, including a definition of PPD< or =6 mm, BoP - and bone loss < 0.2 mm annually for success, the rates for HS were 78%, for HC 65% and for AHC 67%, respectively. Basing success criteria purely on clinical parameters (without radiographic analysis), such as: PPD< or =5 mm and BoP-, the success rates increased to 90%, 76% and 89%, respectively. With PPD< or =6 mm and BoP - as success criteria chosen, the respective rates were 94%, 82% and 94% for HS, HC and AHC implants, respectively. CONCLUSIONS: A significantly higher survival rate as well as a significantly lower incidence of peri-implantitis was identified for hollow screw design ITI Dental Implants after 10 years of service when compared to hollow cylinder design ITI Dental Implants (95.4% vs. 85.7%; 10% vs. 29%). Depending on the setting of the threshold criteria for success, success rates are highly variable and hence, reporting of success rates with elaboration on the criteria set appears crucial for comparison of different studies. 相似文献
7.
Norbert Moszner Urs Karl Fischer J?rg Angermann Volker Rheinberger 《Dental materials》2008,24(5):694-699
OBJECTIVES: The objective of this study was to investigate the use of a new, partially aromatic urethane dimethacrylate in visible-light cured resin-based composite restoratives. Selected mechanical properties, such as flexural strength and flexural modulus of elasticity, of model monomer mixtures and composites containing the new urethane dimethacrylate were investigated and compared to the properties of materials that are based on Bis-GMA, at present the most frequently used cross-linker in restorative composites. In addition, the polymerization shrinkage and the water sorption of selected composites were determined. METHODS: The flexural strength, flexural modulus of elasticity, and the water sorption were determined according to ISO 4049:2000. Test specimens (rods: 2 mmx2 mmx25 mm; discs: d=15 mm and h=1 mm) of the investigated composites were prepared in stainless steel molds and light-cured (150 mW/cm2, 2x180 s). The flexural strength and flexural modulus of rods were measured after the samples had been stored under dry conditions or in water for 24 h at 37 degrees C as well as after they had been stored in water for 7 days at 37 degrees C. The water sorption was determined with discs. The polymerization shrinkage was calculated from the densities of the uncured composite pastes and cured composites. RESULTS: Visible light cured mixtures of dimethacrylate diluents with the new urethane dimethacrylate and composites based on these mixtures show a reactivity, flexural strength, flexural modulus of elasticity, polymerization shrinkage and water sorption similar to those of materials that are based on Bis-GMA. The composites did not show any strong deterioration of the mechanical properties after water storage. 相似文献
8.
Buser D Chen ST Weber HP Belser UC 《The International journal of periodontics & restorative dentistry》2008,28(5):441-451
Early implant placement is one treatment option for implant therapy following single-tooth extraction in the anterior maxilla. The surgical technique presented here is characterized by tooth extraction without flap elevation, a 4- to 8-week soft tissue healing period, implant placement in a correct three-dimensional position, simultaneous contour augmentation on the facial aspect with guided bone regeneration using a bioabsorbable collagen membrane combined with autogenous bone chips and a low-substitution bone filler, and tension-free primary wound closure. The surgical step-by-step procedure is presented with a case report. In addition, the biologic rationale is discussed. 相似文献
9.
Müller-Richter UD Kohlhof JK Reichert TE Roldán JC 《The British journal of oral & maxillofacial surgery》2008,46(4):325-327
Undifferentiated pleomorphic sarcoma (formerly known as malignant fibrous histiocytoma) has been established as an entity in the WHO-classification of soft tissue tumors since 2002. Before this the term "malignant fibrous histiocytoma" has been a collective term for soft tissue malignancies that had no distinct components and included most soft tissue sarcomas (40%). With the new classification they account for only about 5%, and tumors arising in the head and neck contribute only about 1-3% of all undifferentiated pleomorphic sarcomas. We report a rare case in which the orbital region was involved. 相似文献
10.
Bernard JP Szmukler-Moncler S Pessotto S Vazquez L Belser UC 《Clinical oral implants research》2003,14(5):593-600
Abstract: The anchorage of machined Brånemark and ITI TPS‐coated implants of various lengths was investigated in an animal model. Brånemark fixtures 7 and 10 mm long and ITI implants 6 and 10 mm long were inserted in the mandible of dogs and were reverse‐torqued after 3 months of healing. The failing mode was different for the two implant systems. For the ITI implants, loosening coincided with the peak reverse‐torque values. For the Brånemark fixtures, two reverse‐torque values were identified and recorded, a ‘start to rotate’ and a peak value. The ‘start to rotate’ values for the 7 and 10 mm Brånemark fixtures were 36.67 and 38.57 Ncm, respectively, the peak values were 61.88 and 69.13 Ncm. The increase in implant length from 7 to 10 mm did not significantly improve the anchorage. The mean reverse‐torque values for the 6‐ and 10‐mm ITI implants were 104.66 and 192.25 Ncm, respectively; the difference was statistically significant. The mean removal torque of the 6‐mm ITI implant was higher than the 7‐ and 10‐mm Brånemark implants. It is suggested that the distinct anchorage magnitude and the distinct loosening patterns registered for both implant systems might be related to the various surface states. The latter might account for the different failure tendencies mentioned in the literature for short Brånemark and ITI implants. 相似文献