Home About us Contact
|
Home About us Contact | ||
|
|
||
Vertical Height (vertical + height)
Selected AbstractsSegmental osteotomy to reposition multiple osseointegrated dental implants in the anterior maxilla in a trauma patientDENTAL TRAUMATOLOGY, Issue 1 2007Shou-Yen Kao Abstract,,, A 16-year-old young man had severe loss of alveolar bone and lost four teeth in the anterior maxilla because of traumatic injury in a traffic accident. To overcome the surgically compromised condition for implant rehabilitation, the deficient ridge was augmented by autogenous bone graft from the mandibular symphysis. The augmented ridge had much improvement in width but less in vertical height. Four implants were placed to gain initial osseointegration. Segmental osteotomy was performed to occlusally reposition the implants and bone for 5-mm in the anterior maxilla. After 2 years of clinical follow-up, the rehabilitation outcome is satisfactory and stable. [source] Enhancing Effect of Tob Deficiency on Bone Formation Is Specific to Bone Morphogenetic Protein-Induced Osteogenesis,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2002Michihiko Usui Abstract Tob is a recently reported novel bone morphogenetic protein (BMP) inhibitor, which originally was identified by West-Western procedure using ErbB2 as a probe and contains a nuclear localization signal. To further characterize the effects of Tob deficiency on BMP-induced new bone (NB) formation, we examined microcomputed tomography (,CT) on the cross-section of the bone induced by daily injection with BMP onto the calvariae of newborn mice. The calvariae of the saline-injected Tob-deficient (TD) mice were similar to those of the saline-injected or untreated wild-type (WT) mice. BMP injection locally produced NB on the calvaria in WT mice as known previously. In contrast to WT mice, BMP injection onto the calvariae of TD mice produced a calcified area in the cross-section of NB, which was more than that produced by BMP in the WT calvariae. In addition, the horizontal width and the vertical height of the NB induced by BMP in TD mice were several-fold more than those in WT mice. The effect of Tob deficiency on bone-forming activity was selective to the response to the injection with BMP because the levels of injury-induced NB formation examined by ,CT 10 days after bone marrow ablation in the femora were similar between the TD and WT mice. These data indicate that Tob acts as a novel specific antagonist against bone formation induced by BMP treatment in bone. [source] Measurements by MRI of the settling and packing of solid particles from aqueous suspensionsAICHE JOURNAL, Issue 6 2009Julio Acosta-Cabronero Abstract This study extends the application of existing magnetic resonance imaging methods to measure the settling of solid particles from aqueous suspensions. The acquisition of one-dimensional multiecho projections allowed the direct measurement of initial magnetizations (M0), from which solid volume fractions along the sedimentation column were inferred. For polystyrene beads, it was found that monoexponential curves accurately fitted the transverse relaxation decays. In contrast, for the other four solids investigated (activated carbon, talc, calcium carbonate, and glass beads), the single exponential model did not suffice and additional terms in the fitting function significantly improved the calculation of solid concentrations. Additional information about particle sizes was obtained by comparing volume fractions with the spin,spin relaxation times of the hydrogen protons as a function of the vertical height through the sedimenting suspensions of activated carbon and polystyrene beads. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Cross-Sectional Imaging Characteristics of Pituitary Adenomas, Invasive Adenomas and Adenocarcinomas in Dogs: 33 Cases (1988,2006)JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2010Rachel E. Pollard Background: Pituitary tumors in dogs can be adenomas, invasive adenomas, or adenocarcinomas. In people, invasive adenomas and pituitary adenocarcinomas carry a worse prognosis than adenomas. Hypothesis/Objective: To identify differentiating features on cross-sectional imaging in dogs with pituitary adenomas, invasive adenomas, and adenocarcinomas. Animals: Thirty-three dogs that had computed tomography (CT) or magnetic resonance imaging (MRI) performed and a necropsy diagnosis of pituitary adenoma (n= 20), invasive adenoma (n= 11), or adenocarcinoma (n= 2). Methods: Medical records were retrospectively reviewed for signalment, history, and diagnosis. CT and MR images were reviewed for characteristics of pituitary tumors. Results: Mean (± standard deviation) age for dogs with pituitary adenomas (10.6 ± 2.9 years) was greater than that of those with invasive adenomas (8.3 ± 2.7 years, P= .04). Eighteen out of 20 (90%) dogs with adenomas had contrast-enhancing masses. Thirteen out of 20 (65%) had homogeneous enhancement. Mean adenoma height was 1.2 ± 0.7 cm. Eight out of 20 (40%) adenomas were round and 8/20 (40%) compressed surrounding brain. Eleven out of 11 dogs (100%) with invasive adenomas had contrast-enhancing masses. Seven out of 11 (64%) masses were homogeneous. Mean invasive adenoma height was 1.8 ± 0.7 cm, which was significantly greater than adenomas (P= .03). Mass shape varied from round to oval to irregular. Six out of 11 (55%) masses compressed surrounding brain. Clinical and imaging features were variable for 2 dogs with adenocarcinomas. Conclusions and Clinical Relevance: Invasive adenoma should be suspected if a dog with a pituitary tumor is <7.7 years of age and has a mass >1.9 cm in vertical height. Adenocarcinomas are uncommon and metastatic lesions were not seen with imaging. [source] Sculpturing a fibular flap: Combined horizontal/vertical osteotomy and ostectomy for reconstruction of complex craniofacial defects with one flapMICROSURGERY, Issue 8 2005Ayhan Okumus M.D. A fibular flap has great versatility in reconstructive procedures. Osteomies and ostectomies enable the flap to be used for variable defects. We used combined horizontal/vertical osteotomy and ostectomy for reconstruction of complex craniofacial defects with one flap in two patients. Vertical osteotomy transforms the tubular structure of a fibula into a flat bone that can be used for reconstruction of wider defects with less vertical height. Neither vertical osteotomy nor ostectomy had negative effects on viability and bony healing of the segments in our patients. We think that the fibular flap, thanks to its versatility, can be used for reconstruction of complex orbito-zygomatic and orbito-cranial defects successfully. © 2005 Wiley-Liss, Inc. Microsurgery 25:589,595, 2005. [source] UNSTEADY STATE DISPERSION OF AIR POLLUTANTS UNDER THE EFFECTS OF DELAYED AND NONDELAYED REMOVAL MECHANISMSNATURAL RESOURCE MODELING, Issue 4 2009MANJU AGARWAL Abstract In this paper, we present a two-dimensional time-dependent mathematical model for studying the unsteady state dispersion of air pollutants emitted from an elevated line source in the atmosphere under the simultaneous effects of delayed (slow) and nondelayed (instantaneous) removal mechanisms. The wind speed and coefficient of diffusion are taken as functions of the vertical height above the ground. The deposition of pollutants on the absorptive ground and leakage into the atmosphere at the inversion layer are also included in the model by applying appropriate boundary conditions. The model is solved numerically by the fractional step method. The Lagrangian approach is used to solve the advection part, whereas the Eulerian finite difference scheme is applied to solve the part with the diffusion and removal processes. The solutions are analyzed to observe the effects of coexisting delayed and nondelayed removal mechanisms on overall dispersion. Comparison of delayed and nondelayed removal processes of equal capacity shows that the latter (nondelayed) process is more effective than the former (delayed removal) in the removal of pollutants from the atmosphere. [source] Theoretical study on adsorption and diffusion of N atoms on Cu low-index surfaceCHINESE JOURNAL OF CHEMISTRY, Issue 11 2004Zhao-Yu Diao Abstract The adsorption and diffusion of N atoms on the three low-index Cu planes were studied using 5-parameter Morse potential (5-MP) method, and the best theory-experiment agreement was obtained. N atom of Cu(100) surface sit on the fourfold hollow site with the vertical height of 0.018 nm closely coplanar with the topmost copper layer, and the four CuN bond lengths are 0.182 nm and the fifth CuN distance is 0.199 nm. For Cu(111) system, the existence of aberrant Cu(100) reconstructed structure is approved at higher coverage, and at low coverage the structure is almost an ideal Cu(111) surface structure. With respect to Cu(110) system, the N atoms are adsorbed at LB and H3 sites, not at SB site. The diffusion passage and diffusion barrier of adsorbed N atoms were also studied. [source] Double-blind randomized controlled trial study on post-extraction immediately restored implants using the switching platform concept: soft tissue response.CLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2009Preliminary report Abstract Aim: To evaluate the soft tissue response to immediately placed implants using the platform switching concept. Material and methods: In 22 patients, 22 implants of 5.5 mm platform diameter were placed immediately into fresh extraction sockets in maxillae without compromised bone tissue. Eventual post-extraction bone defects were filled using bovine bone matrix mixed with collagen. Immediately after insertion, implants were randomly divided: 11 implants were connected with a 3.8 mm diameter abutment (test group) and 11 with a 5.5 mm diameter abutment (control group). A provisional crown was adapted and adjusted for non-functional immediate positioning. Two months later, definitive prosthetic rehabilitation was performed. Periodontal parameter, buccal peri-implant mucosal changes (REC), mesial and distal papilla height (PH) and vertical height of jumping distance (VHG) were measured at the time of implant placement, of definitive prosthesis insertion and every 6 months thereafter. Results: The mean follow-up was 25 months. All implants were clinically osseointegrated. The test group showed a +0.18 mm REC gain. PH gain was +0.045 mm on average. The mean values were statistically significant (P,0.005) compared with the control group (PH=,0.88 mm; REC=,0.45 mm). No difference between the two groups in periodontal parameters was found. The mean value of bone filling was 7.51 mm in the test group (97.4% of VHG) and 8.57 mm in the control group (95.2% of VHG). No statistically significant difference was found between the two groups. Conclusions: This study suggests that, in a limited time period of 2 years, immediately placed implants with subsequent platform switching can provide peri-implant tissue stability. [source] Dental implants placement in conjunction with osteotome sinus floor elevation: a 12-year life-table analysis from a prospective study on 588 ITI®implantsCLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2006Nicola Ferrigno Abstract Objectives: The purpose of this prospective study was to evaluate the clinical success of placing ITI dental implants in the posterior maxilla using the osteotome technique. Material and methods: All implants were placed following a one-stage protocol (elevating the sinus floor and placing the implant at the same time). Five hundred and eighty-eight implants were placed in 323 consecutive patients with a residual vertical height of bone under the sinus ranging from 6 to 9 mm. The mean observation follow-up period was 59.7 months (with a range of 12,144 months). This prospective study not only calculated the 12-year cumulative survival and success rates for 588 implants by life-table analysis but also the cumulative success rates for implant subgroups divided per implant length and the percentage of sinus membrane perforation were evaluated. Results: The 12-year cumulative survival and success rates were 94.8% and 90.8%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93.4%) compared with 10 and 8 mm long implants (90.5% and 88.9%, respectively). During the study period, only 13 perforations of the Schneiderian membrane were detected with a perforation rate of 2.2% (13 perforations/601 treated sites). Ten perforations out of 13 were caused during the first half of the study period and of these, seven were detected during the first 3 years of this prospective study. Conclusion: Based on the results and within the limits of the present study, it can be concluded that ITI implant placement in conjunction with osteotome sinus floor elevation represents a safe modality of treating the posterior maxilla in areas with reduced bone height subjacent to the sinus as survival and success rates were maintained above 90% for a mean observation period of ,60 months. Shorter implants (8 mm implants) did not significantly fail more than longer ones (10 and 12 mm implants): the differences were small compared with the number of events; hence, no statistical conclusion could be drawn. But, from the clinical point of view, the predictable use of short implants in conjunction with osteotome sinus floor elevation may reduce the indication for complex invasive procedures like sinus lift and bone grafting procedures. [source] Growth analysis of a patient with ectodermal dysplasia treated with endosseous implants: 6-year follow-upJOURNAL OF ORAL REHABILITATION, Issue 3 2006T. ALCAN summary, The purpose of this article is to report the clinical course and 6-year follow-up of a child with ectodermal dysplasia who was treated with implants surgery very early. This article reports placement of mandibular endosseous implants in a 4-year-old patient with hypohidrotic ectodermal dysplasia and oligodontia. This congenital anomaly does not appear to retard healing and the osseointegration remains after 6 years and 3 months of loading. Mandibular and maxillary skeletal growth and development was normal. However, because of lack of alveolar growth, in time, patient's vertical growth pattern changed to low angle. This could be corrected by changing the vertical heights of the abutment and prosthesis. As a result, in ectodermal dysplasias cases with anadontia, early implant placement and fixed prosthesis could be a good multidisciplinary treatment option for poor cooperative child. [source] | |||||||||||||