[Zirconia and removable partial dentures]

The present paper deals with the double crown technique in removable prosthodontics. New ceramic materials like zirconia are increasingly used in combination with CAD/CAM technologies for framework fabrication of fixed prosthesis, tooth- or implant-supported. However, zirconia is also a newly accepted material in removable prosthodontics. It replaces gold alloys for the fabrication of primary telescopic crowns. The Galvanoforming technology is preferably used to fabricate the secondary crowns. The combination of both techniques and materials results in a prosthetic reconstruction of high quality, optimum fit and good biocompatibility.

AN EXPERIMENTAL STUDY OF PARTIAL LOW RISK DEPLOYMENT IN A FIXED VEHICLE ENVIRONMENT

This study will look at the passenger air bag (PAB) performance in a fix vehicle environment using Partial Low Risk Deployment (PLRD) as a strategy. This development will follow test methods against actual baseline vehicle data and Federal Motor Vehicle Safety Standards 208 (FMVSS 208). FMVSS 208 states that PAB compliance in vehicle crash testing can be met using one of three deployment methods. The primary method suppresses PAB deployment, with the use of a seat weight sensor or occupant classification sensor (OCS), for three-year old and six-year old occupants including the presence of a child seat. A second method, PLRD allows deployment on all size occupants suppressing only for the presents of a child seat. A third method is Low Risk Deployment (LRD) which allows PAB deployment in all conditions, all statures including any/all child seats. This study outlines a PLRD development solution for achieving FMVSS 208 performance. The results of this study should provide an option for system implementation including opportunities for system efficiency and other considerations. The objective is to achieve performance levels similar too or incrementally better than the baseline vehicles National Crash Assessment Program (NCAP) Star rating. In addition, to define systemic flexibility where restraint features can be added or removed while improving occupant performance consistency to the baseline. A certified vehicles’ air bag system will typically remain in production until the vehicle platform is redesigned. The strategy to enable the PLRD hypothesis will be to first match the baseline out of position occupant performance (OOP) for the three and six-year old requirements. Second, improve the 35mph belted 5th percentile female NCAP star rating over the baseline vehicle. Third establish an equivalent FMVSS 208 certification for the 25mph unbelted 50th percentile male. FMVSS 208 high-speed requirement defines the federal minimum crash performance required for meeting frontal vehicle crash-test compliance. The intent of NCAP 5-Star rating is to provide the consumer with information about crash protection, beyond what is required by federal law. In this study, two vehicles segments were used for testing to compare and contrast to their baseline vehicles performance. Case Study 1 (CS1) used a cross over vehicle platform and Case Study 2 (CS2) used a small vehicle segment platform as their baselines. In each case study, the restraints systems were from different restraint supplier manufactures and each case contained that suppliers approach to PLRD. CS1 incorporated a downsized twins shaped bag, a carryover inflator, standard vents, and a strategic positioned bag diffuser to help disperse the flow of gas to improve OOP. The twin shaped bag with two segregated sections (lobes) to enabled high-speed baseline performance correlation on the HYGE Sled. CS2 used an A-Symmetric (square shape) PAB with standard size vents, including a passive vent, to obtain OOP similar to the baseline. The A-Symmetric shape bag also helped to enabled high-speed baseline performance improvements in HYGE Sled testing in CS2. The anticipated CS1 baseline vehicle-pulse-index (VPI) target was in the range of 65-67. However, actual dynamic vehicle (barrier) testing was overshadowed with the highest crash pulse from the previous tested vehicles with a VPI of 71. The result from the 35mph NCAP Barrier test was a solid 4-Star (4.7 Star) respectfully. In CS2, the vehicle HYGE Sled development VPI range, from the baseline was 61-62 respectively. Actual NCAP test produced a chest deflection result of 26mm versus the anticipated baseline target of 12mm. The initial assessment of this condition was thought to be due to the vehicles significant VPI increase to 67. A subsequent root cause investigation confirmed a data integrity issue due to the instrumentation. In an effort to establish a true vehicle test data point a second NCAP test was performed but faced similar instrumentation issues. As a result, the chest deflect hit the target of 12.1mm; however a femur load spike, similar to the baseline, now skewed the results. With noted level of performance improvement in chest deflection, the NCAP star was assessed as directional for 5-Star capable performance. With an actual rating of 3-Star due to instrumentation, using data extrapolation raised the ratings to 5-Star. In both cases, no structural changes were made to the surrogate vehicle and the results in each case matched their perspective baseline vehicle platforms. These results proved the PLRD is viable for further development and production implementation.

Partial overlap of anti-mycobacterial, and anti-Saccharomyces cerevisiae mannan antibodies in Crohn's disease

AIM: To test whether humoral immune reaction against mycobacteria may play a role in anti-Saccharomyces cerevisiae antibodies (ASCA) generation in Crohn's disease (CD) and/or whether it correlates with clinical subtypes. METHODS: The dominant ASCA epitope was detected by Galanthus nivalis lectin (GNL)-binding assay. ASCA and IgG against mycobacterial lysates (M avium, M smegmatis, M chelonae, M bovis BCG, M avium ssp. paratuberculosis (MAP)] or purified lipoarabinomannans (LAM) were detected by ELISA. ASCA and anti-mycobacterial antibodies were affinity purified to assess cross-reactivities. Anti-mycobacterial IgG were induced by BCG-infection of mice. RESULTS: GNL bound to different extents to mycobacterial lysates, abundantly to purified mannose-capped (Man) LAM from M tuberculosis, but not to uncapped LAM from M smegmatis. Fifteen to 45% of CD patients but only 0%-6% of controls were seropositive against different mycobacterial antigens. Anti-mycobacterial IgG correlated with ASCA (r = 0.37-0.64; P = 0.003-P < 0.001). ASCA-positivity and deficiency for mannan-binding lectin synergistically associated with anti-mycobacterial IgG. In some patients, anti-mycobacterial antibodies represent cross-reactive ASCA. Vice-versa, the predominant fraction of ASCA did not cross-react with mycobacteria. Finally, fistulizing disease associated with antibodies against M avium, M smegmatis and MAP (P = 0.024, 0.004 and 0.045, respectively). CONCLUSION: Similar to ASCA, seroreactivity against mycobacteria may define CD patients with complicated disease and a predisposition for immune responses against ubiquitous antigens. While in some patients anti-mycobacterial antibodies strongly cross-react with yeast mannan; these cross-reactive antibodies only represent a minor fraction of total ASCA. Thus, mycobacterial infection unlikely plays a role in ASCA induction.

PARTITIONING THE BLOCKS OF A STEINER TRIPLE SYSTEM INTO PARTIAL PARALLEL CLASSES

Does there exist a Steiner Triple System on v points, whose blocks can be partitioned into partial parallel classes of size m, where m ≤ [v⁄3], m | b and b is the number of blocks of the STS(v)? We give the answer for 9 ≤ v ≤ 43. We also show that whenever 2|b, v ≡ 3 (mod 6) we can find an STS(v) whose blocks can be partitioned into partial parallel classes of size 2, and whenever 4|b , v ≡ 3 (mod 6), there exists an STS(v) whose blocks can be partitioned into partial parallel classes of size 4.

Benson's Theorem for Partial Geometries

In 1970 Clark Benson published a theorem in the Journal of Algebra stating a congruence for generalized quadrangles. Since then this theorem has been expanded to other specific geometries. In this thesis the theorem for partial geometries is extended to develop new divisibility conditions for the existence of a partial geometry in Chapter 2. Then in Chapter 3 the theorem is applied to higher dimensional arcs resulting in parameter restrictions on geometries derived from these structures. In Chapter 4 we look at extending previous work with partial geometries with α = 2 to uncover potential partial geometries with higher values of α. Finally the theorem is extended to strongly regular graphs in Chapter 5. In addition we obtain expressions for the multiplicities of the eigenvalues of matrices related to the adjacency matrices of these graphs. Finally, a four lesson high school level enrichment unit is included to provide students at this level with an introduction to partial geometries, strongly regular graphs, and an opportunity to develop proof skills in this new context.

Removable partial dentures

On one side, prosthodontic reconstructions compensate for the sequelae of negative changes in the oral cavity; on the other side, they often enhance or accelerate them. As a consequence of negative changes in the oral cavity over time, treatment planning for RPDs becomes highly complex. A set of reliable criteria is necessary for decision-making and problem management It appears that the majority of published data on RPDs does not depict high effectiveness of this treatment modality. From a strict point of view of evidence-based dentistry, the level of evidence is low if not missing for RPDs. Randomized controlled trials on RPDs are difficult to design, they are not feasible for some questions due to the complexity of the material, or may remain without clinical relevance. The literature rarely gives information on the denture design, tooth selection, and management of the compromised structural integrity of teeth. So far treatment outcomes with RPDs must be considered under the aspect of bias due to the bias in indication and patient selection for RPDs. Better clinical models should be elaborated with more stringent concepts for providing RPDs. This encompasses: risk analysis and patient assessment, proper indications for maintenance or extraction of teeth, strategic placement of implants, biomechanical aspects, materials, and technology. Although there is a tendency to offer fixed prostheses to our patients, this might change again with demographic changes and with an increase in the ageing population, an increase in their reduced dentition, and low socioeconomic wealth in large parts of the world.

Numerical investigation of the mechanical loading of supporting soft tissue for partial dentures

The aim of this research was to study the impact of loading on partial dentures within the supporting soft tissue with respect to different attachment techniques. A finite element model was developed to calculate the stress and strain distribution in this tissue. The model consisted of the left half of a mandible with three remaining teeth that had suffered an atrophy in the anterior region, and a partial denture over the toothless area that was connected at the left mandibular canine using an attachment system. Resulting stress/strain distributions are presented for different load cases using a commercially available prefabricated attachment system.

Unanticipated Partial Behavioral Reflection: Adapting Applications at Runtime

Dynamic, unanticipated adaptation of running systems is of interest in a variety of situations, ranging from functional upgrades to on-the-fly debugging or monitoring of critical applications. In this paper we study a particular form of computational reflection, called unanticipated partial behavioral reflection, which is particularly well-suited for unanticipated adaptation of real-world systems. Our proposal combines the dynamicity of unanticipated reflection, i.e. reflection that does not require preparation of the code of any sort, and the selectivity and efficiency of partial behavioral reflection. First, we propose unanticipated partial behavioral reflection which enables the developer to precisely select the required reifications, to flexibly engineer the metalevel and to introduce the meta behavior dynamically. Second, we present a system supporting unanticipated partial behavioral reflection in Squeak Smalltalk, called Geppetto, and illustrate its use with a concrete example of a web application. Benchmarks validate the applicability of our proposal as an extension to the standard reflective abilities of Smalltalk.

[Partial femur head necrosis in adults--results with intertrochanteric osteotomy and revascularization]

Osteotomy and revascularization have both been used for many years in the therapy of partial aseptic necrosis of the femoral head in the adult. We first attempted a combination of the two techniques in 1978. Stress on the necrotic sector was relieved by intertrochanteric osteotomy, and the necrotic part of the bone was revascularized with a pedicled iliac crest bone graft based on the deep circumflex iliac vessels. Long-term results are now available in 45 hips in 38 patients, with a mean follow-up time of 32 months. Clinically, 71% of the hips were rated very good or good, and among those classed as stage II before surgery the results were rated as very good or good in as many as 90%. Subjective evaluation of the hips by the patients confirmed these results: 85% of the hips were judged to be optimal or markedly improved compared with before operation. Radiological evaluation showed further flattening of the femoral head in one case. A segmental collapse of the femoral head, i.e. stage III lesion according to Ficat, occurred in 2 hips with stage II preoperatively. In 6 hips with stage III necrosis preoperatively secondary arthritis developed. Computerized tomograms taken of all 25 hips from which metal implants had been removed showed signs of integration of the graft in 68%. Scintigraphy with 99-Tc-diphosphonate showed a homogeneous uptake in 42.8% and a non-homogeneous uptake in the remaining 57.2% of the cases. So-called photopenia was not observed in any of the hip joints treated.(ABSTRACT TRUNCATED AT 250 WORDS)

Accelerated partial breast irradiation with interstitial brachytherapy as second conservative treatment for ipsilateral breast tumour recurrence: multicentric study of the GEC-ESTRO Breast Cancer Working Group

PURPOSE To analyse the clinical outcome after salvage lumpectomy and multi-catheter brachytherapy (MCB) for ipsilateral breast tumour recurrence (IBTR). MATERIAL AND METHODS Between 09/00 and 09/10, 217 patients presenting an IBTR underwent lumpectomy and MCB (low, pulsed, or high-dose rate). Survival rates without second local recurrence (2nd LR), distant metastasis (DM), and overall survival (OS) were analysed as well as late effects and cosmetic results. Univariate and multivariate analyses (MVA) based on IBTR data were performed to find prognostic factors for 2nd LR, DM, and OS. RESULTS Median follow-up after the IBTR was 3.9 years [range: 1.1-10.3]. Five and 10-year actuarial 2nd LR rates were 5.6% [range: 1.5-9.5] and 7.2% [range: 2.1-12.1], respectively. Five and 10-year actuarial DM rates were 9.6% [range: 5.7-15.2] and 19.1% [range: 7.8-28.3], respectively. Five and 10-year actuarial OS rates were 88.7% [range: 83.1-94.8] and 76.4% [range: 66.9-87.3], respectively. In MVA, histological grade was prognostic factor for 2nd LR (p=0.008) and OS (p=0.02); while tumour size was prognostic factor for DM (p=0.03). G3-4 complication rate was 11%. Excellent/good cosmetic result was achieved in 85%. CONCLUSION This study suggests that in case of IBTR, lumpectomy plus MCB is feasible and effective in preventing 2nd LR with an OS rate at least equivalent to those achieved with salvage mastectomy.