Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Prosthesis Coloring”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32Linked to original sources
PubMed2000

Pseudoaneurysm formation after infected modified Blalock-Taussig shunt: echocardiographic findings.

The modified Blalock-Taussig (B-T) shunt is well recognized as a palliative procedure for cyanotic congenital heart disease in infants. Pseudoaneurysm formation after a modified B-T shunt is a rare complication. We present the case of a 9-month-old girl with tetralogy of Fallot who had undergone a modified left B-T shunt at 5 months of age and developed a pseudoaneurysm after an episode of infective endocarditis as detected by echocardiography. Compression of the left bronchus, displacement of the mediastinum to right chest, and paralysis of the left hemidiaphragm were found. Magnetic resonance images, computed tomography scans, aortograms, and selective angiograms demonstrated the presence of a large pseudoaneurysm. The compression syndrome gradually disappeared after aneurysmectomy.

Anastomosis, Surgical↗
PubMed1995

Pseudoaneurysm following aortic homograft: clinical implications?

OBJECTIVE: To determine the prevalence of pseudoaneurysm formation after aortic (left ventricular outflow tract) homograft implantation and to evaluate predisposing factors. METHODS: Echocardiographic data were analysed in 30 patients for evidence of pseudoaneurysm formation after homograft implantation. Pseudoaneurysm was characterised as a perfused echo-free space between the homograft and the native aortic wall communicating with the left ventricular outflow tract. Clinical data were analysed for potential predisposing factors for pseudoaneurysm formation. RESULTS: Pseudoaneurysms were found in 22 of 30 patients. Mean age, length of follow up after surgery, aortic systolic pressure gradient (15 (SD 12) v 10 (4) mm Hg), aortic root diameter, and size of the homografts were comparable in patients with and without pseudoaneurysm. preoperative infection, operating techniques, and whether first or reoperation did not affect pseudoaneurysm formation. However, pseudoaneurysms were often localised at the site of an abscess or a paravalvular leak after eradicated prosthetic valve endocarditis. CONCLUSIONS: (1) Doppler echocardiography demonstrates that pseudoaneurysm formation is common after aortic homograft implantation. (2) A prospective study is needed to clarify the prognostic importance of pseudoaneurysms. (3) The high incidence of pseudoaneurysm formation may lead to an improvement of surgical technique (application of fibrin glue).

Adult↗
PubMed1993

Protection from atherosclerosis in vein grafts by a rigid external support.

Atherosclerosis is a common feature of autogenous vein bypass grafts resulting in their long-term failure. Arterial pressure-induced distension is thought to play a major role in the wall thickening of vein grafts, which may in turn favor atherosclerotic complications. In this study, we evaluated the influence of vein distension on the development of atherosclerotic lesions in jugular vein grafts interposed into the common carotid arteries of rabbits. The proximal half of each vein graft was wrapped with a 4-mm-diameter polytetrafluoroethylene graft that reduced the vein graft diameter by 46 +/- 5%. Fourteen animals were fed a 1% cholesterol-rich diet for 8 weeks, and five animals were fed a normal diet. In normocholesterolemic and hypercholesterolemic animals, the wall thickness and the total cross-sectional area were significantly reduced in wrapped compared with unwrapped segments. Foam cells were never observed in normocholesterolemic animals. In hypercholesterolemic rabbits, the sudanophilic lesions covered 62 +/- 4% of the luminal surface in unwrapped segments and 31 +/- 7% in wrapped segments (p < 0.0001). In transverse sections, the surface areas of foam cells were also markedly reduced in wrapped compared with unwrapped segments. Reduction of the wall distension using a rigid external support protected the vein grafts from atherosclerosis, possibly as a result of the decrease in wall thickening that occurred in response to arterialization.

Analysis of Variance↗
PubMed1980

Physical properties of maxillofacial elastomers under conditions of accelerated aging.

The stability of the physical properties of various commercially available maxillofacial prosthetic materials was evaluated with the use of an accelerated aging chamber. The tensile strength, maximum percent elongation, shear strength, tear energy, and Shore A hardness were determined before and after accelerated aging. Results indicate that silicone 44210, a RTV rubber, is a promising elastomer for maxillofacial application.

Chemical Phenomena↗
PubMed1981

Stain removal from a silicone maxillofacial elastomer.

In this study, environmental stains were removed from maxillofacial elastomers by solvent extraction. Silastic 44210, an RTV silicone with proven color and physical property stability, was stained with lipstick, disclosing solution, and methylene blue. These stains were then removed by solvent extraction with each of four chemically dissimilar solvents, namely: toluene, benzene, 1,1,1-trichloroethane, and n-hexane. An additional series of samples was prepared with 11 maxillofacial pigments, not for staining, but for evaluation of pigment stability. Results obtained from spectrophotometric measurements before and after solvent extraction demonstrated the effectiveness of solvent extraction in removing stains, while there was little or no change in the color of the pigments or the base elastomer.

Chemical Phenomena↗
PubMed1982

Stain removal from a pigmented silicone maxillofacial elastomer.

The removal of environmental stains from a pigmented maxillofacial elastomer was carried out by solvent extraction under network swelling. Silastic 44210 was pigmented with 11 maxillofacial pigments prior to staining. Samples were stained with lipstick, methylene blue, and disclosing solution. These stains were then removed by solvent extraction with 1,1,1-trichloroethane. Color parameter measurements both before and after staining and after solvent extraction demonstrated the effectiveness of removing these stains by solvent extraction while causing little or no change in the color of the pigmented samples.

Color↗
PubMed1987

The color accuracy of the Kubelka-Munk theory for various colorants in maxillofacial prosthetic material.

The reflectance model developed by Kubelka and Munk was evaluated for agreement in color prediction of thick pigmented samples and for linearity of optical absorption and scattering coefficients with concentration of colorant in maxillofacial elastomer. The colorants tested were generic opacifiers, dry mineral earth pigments, and fibrous colorants. Significant linear relationships were commonly found between the optical coefficients and the concentration of the colorants. These relationships indicated occasional optical interaction between the colorants and the elastomer. Color differences between theoretical and observed colors of the thick samples averaged 2.96, 3.47, and 1.60 for the opacifiers, mineral earth pigments, and fibrous colorants, respectively, when measured using the CIELAB uniform-color space. The agreement between theoretical and observed colors was significantly closer for the fibrous colorants than for the dry mineral earth pigments of the same labeled color.

Color↗
PubMed1992

Low accuracy of color Doppler ultrasound in the detection of proximal leg vein thrombosis in asymptomatic high-risk patients. The RD Heparin Arthroplasty Group.

OBJECTIVE: To evaluate the ability of color Doppler ultrasound to detect proximal deep venous thrombosis (DVT) in asymptomatic high-risk patients who subsequently underwent contrast venography. DESIGN: Prospective cohort study using blinded observers, with contrast venography as the comparison standard. SETTING: Seven medical centers (university and community hospitals) participating in a clinical trial of low-molecular-weight heparin for prevention of DVT. PATIENTS: A total of 385 consecutive patients undergoing elective unilateral hip or knee replacement. MEASUREMENTS: Ten days after surgery or before hospital discharge (whichever occurred first), patients had bilateral color Doppler ultrasound examinations of the proximal veins of the lower extremities. Subsequently, a contrast venogram of the operated leg was obtained. RESULTS: Color Doppler ultrasound studies and venograms were both evaluable in 319 of the 385 patients. Deep venous thrombosis was identified by contrast venography in 80 patients (prevalence, 25%; 95% CI, 20% to 30%) and involved the proximal veins in 21 patients (prevalence, 7%; CI, 4% to 10%). For proximal DVT, color Doppler ultrasound showed poor sensitivity (38%; CI, 18% to 62%), moderately good specificity (92%; CI, 89% to 95%), and a poor positive predictive value for this population (26%). CONCLUSION: Color Doppler ultrasound examinations are insensitive to proximal DVT in asymptomatic high-risk patients and should not be substituted for venography for identifying proximal DVT in such patients.

Adolescent↗
PubMed2000

Immediate results of the 'Bioglis' valve use in the surgical treatment of Ebstein's anomaly.

BACKGROUND AND AIM OF THE STUDY: The optimum material for heart valves bioprostheses remains in dispute. We have created a biological valve made from hepatic Glisson's capsule and named 'Bioglis'. Experimental studies have shown the major characteristics of the 'Bioglis' valve to be equivalent to, and in some cases superior to, those of traditional valves made from xenopericardial tissue. We present the first experience of the 'Bioglis' valve use in surgical treatment of Ebstein's anomaly. METHODS: Twelve consecutive patients (age range: 7-48 years) with Ebstein's anomaly who underwent surgery between 1997 and 1999 were reviewed. A 'Bioglis' valve was implanted in all cases; two patients underwent repeat surgery because of incompetence of a previously implanted xenopericardial valve. The 'Bioglis' valve was formed, using a flexible frame, from the hepatic Glisson's capsule of bull calves. Short-term results at between two and 10 weeks after surgery were analyzed. Valvular function of the implanted 'Bioglis' valve was monitored by echocardiography. RESULTS: The implanted 'Bioglis' valve diameter ranged from 31 to 33 mm. There were no in-hospital deaths or complications. Echocardiography showed good function of the bioprostheses. Consequent peak and mean pressure gradients across the biological valve ranged from 3 to 7 mmHg and from 1.2 to 2.3 mmHg, respectively. Valve insufficiency occurred in one patient, but was minimal. CONCLUSION: Preliminary results with the 'Bioglis' support our recommendation of this new biological valve for clinical use.

Adolescent↗
PubMed1989

Esthetic and physiologic considerations in metallic framework design.

The metal framework is the essential precursor to a successful porcelain fused to metal fixed partial denture. The framework should be rigid not by bulkiness, but by design. Pontics must be supported to span the edentulous space and replace the missing dentition while providing adequate space for a 1-mm porcelain veneer. The combined thickness of the metal and porcelain must be sufficient to achieve the desired color and vitality without producing a prosthesis that is morphologically overcontoured. To develop a framework that meets all the requirements of physiology, esthetics, and strength, a diagnostic waxup directs the positioning of connectors and allows planning of both form and support. A properly designed and positioned connector area should allow separation of the units by permitting the development of natural appearing labial embrasures. At the same time, the connector must, by engineered design, provide adequate structural strength to support the porcelain. Designing and fabricating the metallic framework for a fixed partial denture requires planning and an understanding of what is desired in the final form. An outline has been presented that details the connector form and placement and a technique has been suggested for developing a framework that provides optimal strength while allowing space for placement of esthetically contoured porcelain.

Dental Abutments↗