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Objectives: To investigate the effects, digital impression procedures can have on the threedimensional fit of ceramic partial crowns in vitro. Methods: An acrylic model of a mandibular first molar was prepared to receive a partial coverage all-ceramic crown (mesio-occlusal-distal inlay preparation with reduction of all cusps and rounded shoulder finish line of buccal wall). Digital impressions were taken using iTero (ITE), cara TRIOS (TRI), CEREC AC with Bluecam (CBC), and Lava COS (COS) systems, before restorations were designed and machined from lithium disilicate blanks. Both the preparation and the restorations were digitised using an optical reference-scanner. Data were entered into quality inspection software, which superimposed the records (best-fitalgorithm), calculated fit-discrepancies for every pixel, and colour-coded the results to aid visualisation. Furthermore, mean quadratic deviations (RMS) were computed and analysed statistically with a one-way ANOVA. Scheffé's procedure was applied for multiple compar- isons (n = 5, α = 0.05). Results: Mean marginal (internal) discrepancies were: ITE 90 (92) μm, TRI 128 (106) μm, CBC 146 (84) μm, and COS 109 (93) μm. Differences among impression systems were statistically significant at p < 0.001 ( p = 0.039). Qualitatively, partial crowns were undersized especially around cusp tips or the occluso-approximal isthmus. By contrast, potential high-spots could be detected along the preparation finishline and at central occlusal boxes. Conclusions: Marginal and internal fit of milled lithium disilicate partial crowns depended on the employed digital impression technique. Clinical significance: The investigated digital impression procedures demonstrated significant fit discrepancies. However, all fabricated restorations showed acceptable marginal and internal gap sizes, when considering clinically relevant thresholds reported in the literature. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Machined restorations have been investigated for their preciseness before, while detailed information on the milling-step itself are lacking. Therefore, the aim of this laboratory study was to quantify the effect of a novel milling-procedure on the marginal and internal fit of ceramic restorations. Methods: An acrylic model of a lower left first molar was prepared to receive a ceramic partial crown and was duplicated by one step dual viscosity impressions. Gypsum casts were formed and laser-scanned to realize virtual datasets, before restorations were designed, exported (PRE) and machined from lithium disilicate blanks. Crowns were digitized by a structure-light-scanner to obtain post-milling-data (POST). PRE and POST were virtually superimposed on the reference tooth and subjected to computer-aided-inspection. Visual fit-discrepancies were displayed with colors, while root mean square deviations (RMSD) and degrees of similarity (DS) were computed and analysed by t-tests for paired samples (n =5, α =0.05). Results: The milling procedure resulted in a small increase of the marginal and internal fit discrepancies (RMSD mean: 3μm and 6μm, respectively). RMSD differences were not statistically significant (p =0.495 and p =0.160 for marginal and internal fit, respectively). These results were supported by the DS data. Significance: The products of digital dental workflows are prone to imprecisions. However, the present findings suggest that differences between computer-aided designed and actually milled restorations are small, especially when compared to typical fit discrepancies observed clinically. Imprecisions introduced by digital design or production processes are small. [Copyright &y& Elsevier]

Objectives: A novel three-dimensional scanning technique was used to investigate the effects a one-step and a two-step impression methods can have on the three-dimensional fit of ceramic partial crowns. Methods: An acrylic model of a mandibular first molar was prepared to receive a partial coverage all-ceramic crown (mesio-occlusal-distal inlay preparation with reduction of all cusps and rounded shoulder finish line of buccal wall). Type IV plaster replicates were cast based on one-step single viscosity (OS/SV), one-step dual viscosity (OS/DV), and two-step dual viscosity (TS/DV) impressions. Five partial crowns were fabricated per impression method using hot-pressed lithium disilicate ceramics. Then, preparation and restorations were digitized using a non-contact, white-light scanner featuring self-calibrating optics (overall measurement uncertainty of <5 mm). Data were entered into quality inspection software which superimposed the records (best-fit-algorithm), calculated fit-discrepancies for every pixel, and colour-coded the results to aid visualization. Furthermore, mean quadratic deviations (RMS) were computed and analyzed statistically with a 1-way ANOVA. Scheffé's procedure was applied for multiple comparisons (a = 0.05). Results: Mean RMS-values for marginal (internal) surfaces were: OS/SV 70 (20) mm, OS/DV 78 (34) mm, and TS/DV 107 (52) mm. Differences among impression techniques were statistically significant at p = 0.006 (0.001). Qualitatively, occlusal ridges and preparation finish lines were over contoured, whereas inner occlusal boxes and the proximal-occlusal isthmus were under contoured. Conclusions: OS/SV and OS/DV impressions resulted in statistically significantly smaller marginal and internal discrepancies than the two-step technique. Clinical significance: Marginal and internal fit of hot-pressed lithium disilicate partial crowns depended on the employed impression technique. One-step impressions are preferred over two-step techniques in many day-to-day clinical situations, especially for the fabrication of partial coverage crown restorations. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: The objective of this in vitro study was to visualize and to quantify the marginal and internal fit of heat-pressed ceramic restorations by a novel three-dimensional procedure. Accuracy and reproducibility of the employed measuring method were determined. Methods: An acrylic model of a lower left first molar was prepared to receive a partial crown and duplicated by single step dual viscosity impressions. Corresponding working casts were formed from Type IV die stone and indirect restorations were fabricated from heat-pressable lithium disilicate ceramics (IPS e.max Press, Ivoclar Vivadent AG, Schaan, Liechtenstein). The acrylic tooth model and the ceramic partial crowns were digitized by a structure light scanner with a measurement-uncertainty of 4μm and subjected to computer-aided quality inspection. Visual discrepancies in marginal and internal fit were displayed with colors. For quantitative analysis, mean quadratic deviations (RMS) were computed and analyzed by Student''s t-test (n =5, α =0.05). Results: Mean RMS-values for accuracy (reproducibility) ranged from 34 (14)μm for internal areas to 78 (23)μm for marginal surfaces. Differences in accuracy (p =0.003) and reproducibility (p <0.001) were statistically significant. In general, areas with sharp internal line angles such as occlusal ridges and the preparation finish line exhibited oversized dimensions, whereas areas with rounded and soft internal line angles were undersized. Significance: The viability of a computer-aided and three-dimensional approach for assessing marginal and internal fit of indirect restorations was demonstrated. Thereby, the obtained results track complex form changes as they occur during laboratory processing. [Copyright &y& Elsevier]

Introduction/objectives: Contrast-enhanced MRA (ce-MRA) has been claimed by many authors as a replacement of conventional angiography evaluating peripheral arterial occlusive disease. However, reliable detection of relevant stenoses (>70%) has to be provided for planning vascular interventions. Only few data in the literature focuses on this crucial problem. The purpose of this study was to evaluate this topic using a two-step body-coil-based MRA protocol. Methods and patients: Forty three patients presenting with 82 stenoses ≥50% and 61 stenoses >70% on conventional catheter angiogram received fast Gadolinium-DTPA-enhanced high resolution 3D MR angiography at 1.5 T covering the pelvic and peripheral vascular tree in two examination steps using the body-coil. The data were evaluated double-blinded by three readers distinguishing moderate (50–70%) from severe stenoses (>70%). Results: Overall sensitivity/specificity/accuracy was 84/60/70% evaluating 143 segments. Specificity was rather poor in the iliac (58%) and crural (50%) region and moderate in the femoral and popliteal level (73%). The negative predictive value ranged between 78 and 91%. The grade of stenosis tend to be overestimated rather than underestimated in all levels with positive predictive values between 55 and 78%. Discussions and conclusions: Body-coil-based contrast-enhanced MRA has limited potential in distinguishing moderate from severe stenoses in peripheral occlusive disease. Overestimations are more common than underestimations. Both occur mainly in small-sized crural arteries but also in larger iliac arteries where vessel course in partition direction may cause inadequacy between voxel size and lumen diameter in severe stenosis. [Copyright &y& Elsevier]

Von Hippel-Lindau (VHL) disease is a progressive autosomal dominant multisystem disorder that is associated with a germ line mutation of the VHL gene on the short arm of chromosome 3. A variety of benign and malignant diseases, including eye and CNS hemangioblastomas, renal cell carcinoma and pheochromocytoma are the major components. Gastroenteropancreatic neuroendocrine tumors are also listed among the typical complications, although these occur seldom. Virtually all such tumors are pancreatic islet cell tumors. VHL-associated islet cell tumors are mostly hormone-inactive. They can be detected during screening investigations according to the multidisciplinary disorder or by workup of space-occupying lesions. There are no specific predictors for malignancy in VHL-associated islet cell neoplasias, but tumors smaller than 3 cm in diameter are believed to be always benign. Gadolinium-enhanced MRI is currently the imaging method of choice, but contrast-enhanced CT is also a diagnostic option. The spectrum of manifestations is illustrated by selected cases. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objectives: There is a lack of literature regarding the procedure-specific quality of acute postoperative pain management after midfacial fracture repair. The purpose of the presented prospective clinical study was to evaluate postoperative pain management after surgical repair of midfacial fractures. Materials and methods: Eighty-five adults were evaluated on the first postoperative day following midfacial repair using the questionnaire of the Quality Improvement in Postoperative Pain Management (QUIPS) project. The main outcome measures were patients' characteristics and clinical- and patient-reported outcome parameters. Results: Overall, pain on the first postoperative day was moderate. A significant correlation between process and outcome parameters could be shown. Duration of surgery above the calculated median was significantly associated with higher maximum pain intensity ( p = 0.017). Patients requiring opioids in the recovery room presented significantly higher pain on activity ( p = 0.029) and maximum pain ( p = 0.035). Sleeping impairment ( p = 0.001) and mood disturbance ( p = 0.008) were significantly more prevalent in patients undergoing repair of a centrolateral midfacial fracture. Conclusions: QUIPS is a simple and qualified tool to evaluate the procedure specific quality of acute postoperative pain management. Pain on the first postoperative day following midfacial fracture repair seems overall to be moderate. Nearly a third of the patients showed inadequate postoperative pain management. To prevent inadequate postoperative pain management, it is necessary to establish a continued procedure-specific outcome measurement. [ABSTRACT FROM AUTHOR]

Objectives: Cheek rotation flaps are an established surgical procedure for coverage of facial skin defects especially of the cheek and infraorbital region. A comparison of pre- and postoperative anthropometric measurements may help to objectify intraoperative estimations with regards to postoperative appearance. Materials and methods: We present an evaluation of 31 patients undergoing periorbital reconstruction by a cheek rotation flap on standardized photographs based on reference anthropometric data. Analysis included intercanthal, binocular and eye fissure width, eye fissure, lid sulcus and upper lid height, upper and lower iris coverage, position of cornea to palpebra inferior, scleral show, ectropion, and canthal tilt. Furthermore, it was clearly differentiated whether the defect to cover included eyelid skin or not. Results: Ectropion showed a significant association to surgery ( p = 0.03) and time ( p = 0.03). If the defect to cover included lower eyelid skin, lower iris coverage values decreased significantly ( p = 0.02), meanwhile the rate of scleral show increased significantly ( p < 0.01), indicating pre- to postoperative lower eyelid retraction. Conclusions: In all patients analyzed, indices were reproducible and reliable. An association between surgery and ectropion was detectable. Whenever lower eyelid skin is involved in the defect to be covered, the significantly decreased lower iris coverage and increased rate of scleral show indicate an increased risk of lower lid retraction. Clinical relevance: Whenever eyelid skin is involved in a defect to be covered by a cheek rotation flap, there is an increased risk of postoperative lower lid distortion. Special care has to be taken to perform techniques preventing lower lid retraction. [ABSTRACT FROM AUTHOR]

Objectives: There is an ongoing discussion in the literature about preoperative planning and postoperative evaluation of orthognathic surgery and its impact on facial appearance and aesthetics. Materials and Methods: We present an anthropometric and cephalometric evaluation of orthognathic surgery results based on reference anthropometric data. In 171 Class II patients, mandibular advancement by bilateral sagittal split osteotomy was performed. Preoperative as well as 3 and 9 months postoperative standardized frontal view and profile photographs and lateral cephalograms were evaluated in a standardized manner by use of 21 anthropometric indices. In cephalograms, SNA and SNB angle as well as Wits appraisal were investigated. Results of anthropometric and cephalometric measurements were correlated. Results: Lower vermilion contour, vermilion and cutaneous total lower lip height, nose-lower face height, nose-face height, upper face-face height, upper lip- and chin-mandible height index showed significant pre- to postoperative changes as well as SNB angle and Wits appraisal. Furthermore, medial-lateral cutaneous upper lip height, vermilion and cutaneous total lower lip height and philtrum-mouth width index presented significant correlations to cephalometric measurements. Conclusions: The investigated anthropometric indices and cephalometric measurements presented reproducible results related to surgery. The correlation of cephalometric to anthropometric measurements has been proven useful for preoperative planning and postoperative evaluation of orthognathic surgery patients. Clinical relevance: The presented anthropometric measurements and their observed correlation to cephalometric measurements could lead to a better prediction and optimized planning of the soft tissue result in orthognathic surgery patients and thereby improve the aesthetic outcome. [ABSTRACT FROM AUTHOR]

Objectives: In the literature, there is an ongoing discussion about the influence of orbital fractures and the surgical approach on the rate of eyelid deformities of the lower eyelid. Materials and methods: We present an evaluation of a series of 221 patients 9 months after zygomaticomaxillary complex fracture repair that underwent implant removal. Reference anthropometric data were measured on standardized pre- and postoperative photographs. Analysis included eye fissure width and height, lid sulcus and upper lid height, upper and lower iris coverage, position of cornea to palpebra inferior, canthal tilt, scleral show, ectropion, and entropion. Both operated and contralateral eyelids were evaluated as well as whether a transconjunctival or a subciliary approach was performed. Results: Time, surgery, and surgical approach presented significant effects on eye fissure index and lower iris coverage. Scleral show was significantly influenced by the surgical procedure itself as well as by the type of incision. The rate of ectropion increased significantly pre- to postoperative. Conclusions: The subciliary approach included the highest risk of lower lid retraction. The low pre- to postoperative increase of scleral show and ectropion compared to recent studies gives us an idea about the influence of the underlying trauma on the rate of lower lid retraction. The standardized measurements described are accurately and objective to evaluate postoperative results. Clinical relevance: The transconjunctival approach is preferable in orbital fracture repair. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To determine image quality and lesion detection of sliding multislice (SMS), a recently developed moving table MRI technique, in patients with rectal cancer. Materials and methods: Twenty-seven paired SMS (Avanto, Siemens Medical Solutions) and MDCT (Sensation 64, Siemens Medical Solutions) examinations of abdomen and pelvis were performed in patients with rectal cancer and compared for detection of liver, lymph node and bone metastases by two independent observers. A contrast-enhanced, fat saturated 2D gradient echo sequence (TE, 2.0ms; TR, 102ms; slice, 5mm) was acquired with SMS and a standard contrast-enhanced protocol (100ml @ 2.5ml/s; slice, 5mm) was used for abdominal MDCT. Standard of reference consisted of a consensus evaluation of SMS, MDCT, and all available follow-up examinations after a period of 6 months. Artifact burden and image quality of SMS was assessed in comparison to stationary gradient echo sequences obtained in an age-matched group of 27 patients. Results: Whereas SMS achieved a mean quality score of 3.65 (scale, 0–4) for the liver, representing very good diagnostic properties, strong breathing artifacts in the intestinal region were observed in 19 cases by both observers. The retroperitoneum still achieved a mean quality score of 3.52, although breathing artifacts were noted in 12 and 15 cases (observers 1 and 2, respectively). The sensitivities of SMS to detect hepatic metastases were 91.2% and 94.1% for both observers, respectively, compared to 98.5%/98.5% for MDCT. The sensitivities for lymph node metastases were 87.5%/81.3% for SMS compared to 78.1%/81.3% for MDCT. The sensitivities for bone metastases were 91.7%/100% for SMS compared to 8.3%/16.7% for MDCT. Conclusion: With slightly reduced image quality in the intestinal region, SMS exhibits equal detection of lymph node and liver metastases compared to MDCT. SMS MRI proved to be superior to MDCT in detection of bone metastases. [Copyright &y& Elsevier]

Purpose: To assess pulmonary abnormalities in patients with primary Sjogren's syndrome (PSS) using high-resolution computed tomography (HRCT). Material and Methods: The HRCT scans of 24 patients with the diagnosis PSS were retrospectively reviewed regarding the presence, extension and distribution of 16 pathological findings. Results: Nineteen patients (79.2%) showed pathological findings and in five patients (21.8%) the HRCT scan was judged to be normal. A predominance of abnormalities in the lower lobes and subpleural areas was detected. The following pathologies were found: bronchiectasis, thin-walled cysts and small pulmonary nodules (46.2%), ground-glass attenuation and emphysema (37.8%), interlobular-septal thickening (29.4%), honeycombing (25.2%), bronchial wall thickening, tree-in-bud pattern (21.0%), mosaic perfusion (16.8%), architectural distortion (12.6%). Airspace consolidation, air trapping, large nodules (10-30mm) and masses (>30mm), mediastinal lymph node enlargement (>15mm) and free pleural fluid were seen each in 4.2%. In 7 of the 11 patients with thin-walled cysts areas of ground-glass attenuation were detected. Conclusion: HRCT seems is contributive to the characterization of the wide variety of lung abnormalities in PSS. Airway disease alone or in association with the presence of varying degrees of interstitial disease represents the main findings in accordance with earlier reports. Unexpectedly, almost half of the patients had thin-walled cysts on the HRCT scans, which etiology is unclear but could be associated with areas of ground-glass attenuation indicating LIP. [ABSTRACT FROM AUTHOR]

Reports on a study which evaluated responses to five outbreaks involving more than one member state of the European Union. How international trade and travel has increased the likelihood that outbreaks of infection will involve more than one country; Methods; Common critical control points, including failure to identify and report cases and failure to link information to action; Suggestion that national surveillance systems need to be improved.