949 resultados para Alveolar reconstruction
Resumo:
Background/purpose: The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation. Methods: Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3). Results: In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3. Conclusions: Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used. Published by Elsevier Inc.
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The aim of this study is to evaluate the efficacy of the application of allogenous bone at the maxillo-mandibular reconstructions for future rehabilitation with dental implants. The patients were submitted to reconstruction of maxilla, using allogeneic bone grafts, in 3 different techniques: onlay grafts for lateral ridge augmentation, onlay and particulate bone for sinus lift grafting, and particulate alone for sinus lift grafts. Clinical and radiographic control was done at the postoperative phase for at least 8 months, until the patient could be submitted to the installation of dental implants. The results showed success in the majority of the cases, and dental implants could be installed. This can be considered an excellent alternative when compared with the use of autogenous grafts; because handling is easier, there is a great amount of material available and a possibility of using local anesthesia, and consequently there is a reduction of patient morbidity. (C) 2008 American Association of Oral and Maxillofacial Surgeons
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The absence of an eyebrow, either partial or total, has been observed in patients with craniofacial clefts, such as the Tessier 9 to 13 cleft. Several techniques have been used to improve the appearance of the region, such as island scalp flaps and scalp strip grafting, with limited or marginally satisfactory aesthetic results. The authors report 2 patients with craniofacial clefts in whom a novel technique combining 2 separate surgical approaches, micrografting and tattooing, was used. The use of micrografting with single or double hair units, properly angulated, produces natural-looking and satisfactory results with a minimum of morbidity. Excellent volume and appearance of the eyebrow may be achieved in a single session using this technique. Tattooing performed subsequently over the microimplanted hairs provides the illusion of greater density to the eyebrow, resulting in an appearance closer to normal.
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Human leukocyte antigen (HLA) haplotypes are frequently evaluated for population history inferences and association studies. However, the available typing techniques for the main HLA loci usually do not allow the determination of the allele phase and the constitution of a haplotype, which may be obtained by a very time-consuming and expensive family-based segregation study. Without the family-based study, computational inference by probabilistic models is necessary to obtain haplotypes. Several authors have used the expectation-maximization (EM) algorithm to determine HLA haplotypes, but high levels of erroneous inferences are expected because of the genetic distance among the main HLA loci and the presence of several recombination hotspots. In order to evaluate the efficiency of computational inference methods, 763 unrelated individuals stratified into three different datasets had their haplotypes manually defined in a family-based study of HLA-A, -B, -DRB1 and -DQB1 segregation, and these haplotypes were compared with the data obtained by the following three methods: the Expectation-Maximization (EM) and Excoffier-Laval-Balding (ELB) algorithms using the arlequin 3.11 software, and the PHASE method. When comparing the methods, we observed that all algorithms showed a poor performance for haplotype reconstruction with distant loci, estimating incorrect haplotypes for 38%-57% of the samples considering all algorithms and datasets. We suggest that computational haplotype inferences involving low-resolution HLA-A, HLA-B, HLA-DRB1 and HLA-DQB1 haplotypes should be considered with caution.
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The aim of this study was to unravel the mechanisms by which interleukin (IL)-10, a potent pleiotropic cytokine, modulates alveolar bone homeostasis in C57BL/6 wild-type (WT) and IL-10 knockout (IL-10 KO) mice, evaluated at 8, 24, and 48 wk of age. Interleukin-10 KO mice presented significant alveolar bone loss when compared with WT mice, and this was not associated with changes in leukocyte counts or bacterial load. The levels of expression of messenger RNA (mRNA) for tumor necrosis factor-alpha (TNF-alpha), IL-1 beta, IL-6, transforming growth factor-beta (TGF-beta), receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), and matrix metalloproteinase 13 (MMP13) were similar between both strains, whereas a significant decrease of tissue inhibitor of metalloproteinase 1 (TIMP1) mRNA expression was found at 48 wk in IL-10 KO mice. The osteoblast markers core binding factor alpha1 (CBFA1) and type I collagen (COL-I) were expressed at similar levels in both strains, whereas the levels of alkaline phosphatase (ALP) and osteocalcin (OCN), and those of the osteocyte markers phosphate-regulating gene endopeptidases (PHEX) and dentin matrix protein 1 (DMP1) were significantly lower in IL-10 KO mice. Our results demonstrate that the alveolar bone loss in the absence of IL-10 was associated with a reduced expression of osteoblast and osteocyte markers, an effect independent of microbial, inflammatory or bone-resorptive pathways.
Resumo:
Few studies has been done using guided bone regeneration in maxillary sinus defects. Aim: To assess the bone repair process in surgical defects on the alveolar wall of the monkey maxillary sinus, which communicates with the sinus cavity, by using collagen membranes: Gen-derm - Genius Baumer, Pro-tape - Proline and autologous temporal fascia. Materials and Methods: In this prospective and experimental study, orosinusal communications were performed in four tufted capuchin monkeys (Cebus apella) and histologic analysis was carried out 180 days after. Results: In the defects without a cover (control), bone proliferation predominated in two animals and fibrous connective tissue predominated in the other two. In defects repaired with a temporal fascia flap, fibrous connective tissue predominated in three animals and bone proliferation predominated in one. In the defects repaired with Gen-derm or Pro-tape collagen membranes there was complete bone proliferation in three animals and fibrous connective tissue in one. Conclusions: Surgical defect can be repaired with both bone tissue and fibrous connective tissue in all study groups; collagen membranes was more beneficial in the bone repair process than temporal fascia or absence of a barrier.
Resumo:
Objective: The objective of the study was to compare the functional and aesthetic results of fractured orbital wall reconstruction with an auricular cartilage graft or absorbable polyacid copolymer. Materials and Methods: Twenty patients with blow-out orbital fracture/orbital floor associated or not with the medial wall were assessed by the same craniofacial surgical group. All were evaluated preoperatively and postoperatively by an ophthalmologist for diplopia, enophthalmos, exophthalmos, sensitivity, ophthalmic reflexes, intraocular pressure, and visual field. The patients were subjected to a preoperative facial multislice computed tomographic scan, repeated 6 months after surgery. Eight patients underwent reconstruction with an auricular cartilage graft, and 12 patients, with blade absorbable polyacid copolymer. Subtarsal access was used for all patients. Results: Two patients showed temporary ectropion, 1 in each group. All patients presented satisfactory ocular function, and all tests revealed good orbital delineation, orbital symmetry, periorbital sinus individualization, and reduction of blow-out. Conclusions: The blow-out orbital wall reconstruction can be performed with the use of an auricular cartilage or with a blade absorbable copolymer without differences regarding functional or aesthetic complications and sequelae.
Resumo:
The present report describes an original surgical procedure for the mandibular reconstruction of 2 different defects using a single fibular flap. In addition to the habitual osteotomies, we resected a bone fragment from the middle portion of the flap, with care taken to maintain the integrity of the pedicle throughout its extension to guarantee an adequate blood supply also for the distal portion of the bone flap used for the treatment of the smaller mandibular defect. This simple maneuver permitted the reconstruction of 2 mandibular regions with well-vascularized bone tissue using a single microsurgical flap. (C) 2008 Published by Elsevier Inc.
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In 2007 Associate Professor Jay Hall retires from the University of Queensland after more than 30 years of service to the Australian archaeological community. Celebrated as a gifted teacher and a pioneer of Queensland archaeology, Jay leaves a rich legacy of scholarship and achievement across a wide range of archaeological endeavours. An Archæological Life brings together past and present students, colleagues and friends to celebrate Jay’s contributions, influences and interests.
Resumo:
The present work studied the adverse effects of maternal exposure of rats to alcohol during lactation, on the development of their offspring. Histometric evaluation by karyometry and of the alveolar bone at the level of the first upper molar of the sucking was perfomed. Two groups of animals, one coming from mothers exposed to drinking water containing 20% ethanol during the total lactation period and the other of controls coming from mothers receiving only alcohol-free drinking water during this period. On the 21 first day of lactation the young of each group were aleatorily selected and following anesthesia, their heads severed; after histological treatment, serial 6 mu m sections on the frontal plane at the molar level, stained with hematoxilin and eosin, were obtained. The experimental results produced, suggest that sucking from ethanol-treated mothers, show retarded post-natal growth, their alveolar bones presenting scarce, little calcified trabeculae, and a more abundant bone marrow compared to controls.
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Objective-To evaluate the effects of increasing doses of remifentanil hydrochloride administered via constant rate infusion (CRI) on the minimum alveolar concentration (MAC) of isoflurane in cats. Animals-6 healthy adult cats. Procedures-For each cat, 2 experiments were performed (2-week interval). On each study day, anesthesia was induced and maintained with isoflurane; a catheter was placed in a cephalic vein for the administration of lactated Ringer`s solution or remifentanil CRIs, and a catheter was placed in the jugular vein for collection of blood samples for blood gas analyses. On the first study day, individual basal MAC (MAC(Basal)) was determined for each cat. On the second study day, 3 remifentanil CRIs (0.25, 0.5, and 1.0 mu g/kg/min) were administered (in ascending order); for each infusion, at least 30 minutes elapsed before determination of MAC (designated as MAC(R0.25`) MAC(R0.5`) and MACR(R1.0`) respectively). A 15-minute washout period was allowed between CRIs. A control MAC (MAC Control) was determined after the last remifentanil infusion. Results-Mean +/- SD MAC(Basal) and MAC(Control) values at sea level did not differ significantly (1.66 +/- 0.08% and 1.52 +/- 0.21%, respectively). The MAC values determined for each remifentanil CRI did not differ significantly. However, MACR(0.25`) MAC(R0.5`) and MAC(R1.0) were significantly decreased, compared with MAC(Basal`) by 23.4 +/- 79%, 29.8 +/- 8.3%, and 26.0 +/- 9.4%, respectively. Conclusions and Clinical Relevance-The 3 doses of remifentanil administered via CRI resulted in a similar degree of isoflurane MAC reduction in adult cats, indicating that a ceiling effect was achieved following administration of the lowest dose. (Am J Vet Res 2009;70:581-588)
Resumo:
Purpose: The purpose of this study was to evaluate the area and volume of bone available for grafting in a donor retromolar region using computed tomography (CT). Materials and Methods: Ten patients previously scanned by multislice CT were selected for evaluation. Images from partially and completely dentate patients at least 18 years of age were included in the study; those from patients with impacted or erupted third molars or intrabony lesions in the study area were not included. Computer software with appropriate tools was used to handle the images. Two calibrated observers made measurements separately. Safety margins in relation to the lingual cortex, the base of mandible, and the alveolar canal were established in each cross-section of the CTs. Measurements were done by using cross-sectional views, and the results were calculated after three-dimensional reconstruction, providing area and volume data. Results: The mean area of bone available for grafting was 8.12 cm(2) ( range, 0.00 to 13.60 cm(2)) and 8.32 cm(2) ( range, 0.00 to 14.30 cm(2)) for observers 1 and 2, respectively. Mean available bone volume for grafting was 0.79 cm(3) ( range, 0.00 to 1.50 cm(3)) for observer 1 and 0.85 cm(3) ( range, 0.00 to 1.60 cm(3)) for observer 2. Interobserver analysis showed substantial agreement. Conclusion: The retromolar region showed a wide variety of anatomic differences among patients. Three-dimensional multislice CT allows reproducible measurements of the area and volume of the retromolar region. Int J Oral Maxillofac Implants 2010; 25: 374-378