Implant-supported distal extensions in severely resorbed posterior alveolar ridges

The application of implant-borne rehabilitations in residual alveolar ridges may be restricted by various anatomic conditions, as available bone height and characteristics. Here we report the clinical outcome of implants placed in severely resorbed posterior ridges, in addition to various implant-supported treatment modalities. Extra Oral implants (Straumann, Basel, Switzerland) with the intraosseous length of 2.5–5mm were installed in the posterior alveolar ridges. Following the healing period of 4–6 months, implants were exposed and included in the distal extensions of fixed and removable prosthesis. At recall appointments were collected surgical, clinical and radiological variables, including the evidence of adverse effects. An 8-years life table analysis was calculated. The treatment protocol was applied in thirty-five patients, presenting 31 removable and 4 fixed complete implant-supported dentures. A total of 61 Extra Oral implants were placed posterior to the distal implants, at the mean distance of 29.8mm (range 15.6–62.7mm). Three implants failed during the osteointegration phase, yielding an 8-year cumulative success rate of 92.24%. Following the osteointegration period, no major bone loss or other adverse events were found. The clinical results indicated that the Extra Oral implants may be successfully used in addition to the other, longer implants. Thus, a relatively long extension in the posterior region may be employed. With careful preoperative planning, this technique offers a simple and beneficial complementary treatment option for removable and fixed complete dentures.

The Measurement of Current Efficiency in Zinc Sulphate Electrolytes Containing Antimony and Cobalt by Hydrogen Evolution

The measurement of current efficiency by hydrogen evolution is based on the assumption that the portion of the current which deposits no zinc will release hydrogen. This assumption is correct for solutions containing no impurities electropositive to zinc.

The Electrodeposition of Copper-Cobalt Alloys

An attempt was made to deposit a 50:50 copper-cobalt alloy from various sulfate electrolytes. No true 50:50 alloy was obtained but various mixtures of cobalt and copper rich crystals were deposited.

An Investigation of the Precipitation of Cobalt with Zinc Dust

Cobalt, as well as copper, cadmium, and other impurities, is removed by selective precipitation with zinc during the zinc electrolyte purification cycle, and the purification residue may be treated by a Cadmium Plant for the recovery of cadmium.

A systematic review of the survival and complication rates of implant supported fixed dental prostheses with cantilever extensions after an observation period of at least 5 years

OBJECTIVE: The aim of this systematic review was to assess the survival rates of short-span implant-supported cantilever fixed dental prostheses (ICFDPs) and the incidence of technical and biological complications after an observation period of at least 5 years. MATERIAL AND METHODS: An electronic MEDLINE search supplemented by manual searching was conducted to identify prospective or retrospective cohort studies reporting data of at least 5 years on ICFDPs. Five- and 10-year estimates for failure and complication rates were calculated using standard or random-effect Poisson regression analysis. RESULTS: The five studies eligible for the meta-analysis yielded an estimated 5- and 10-year ICFDP cumulative survival rate of 94.3% [95 percent confidence interval (95% CI): 84.1-98%] and 88.9% (95% CI: 70.8-96.1%), respectively. Five-year estimates for peri-implantitis were 5.4% (95% CI: 2-14.2%) and 9.4% (95% CI: 3.3-25.4%) at implant and prosthesis levels, respectively. Veneer fracture (5-year estimate: 10.3%; 95% CI: 3.9-26.6%) and screw loosening (5-year estimate: 8.2%; 95% CI: 3.9-17%) represented the most common complications, followed by loss of retention (5-year estimate: 5.7%; 95% CI: 1.9-16.5%) and abutment/screw fracture (5-year estimate: 2.1%; 95% CI: 0.9-5.1%). Implant fracture was rare (5-year estimate: 1.3%; 95% CI: 0.2-8.3%); no framework fracture was reported. Radiographic bone level changes did not yield statistically significant differences either at the prosthesis or at the implant levels when comparing ICFDPs with short-span implant-supported end-abutment fixed dental prostheses. CONCLUSIONS: ICFDPs represent a valid treatment modality; no detrimental effects can be expected on bone levels due to the presence of a cantilever extension per se.

Comparative study of four retentive anchor systems for implant supported overdentures--retention force changes

OBJECTIVES: Wear of attachments leads to a loss of retention and potentially reduces the function of complete dentures. This study evaluated the retention force changes of different prefabricated attachment systems for implant-supported overdentures to estimate the wear constancy and applicability in clinical practice. METHODS: Four prefabricated attachment systems were tested [Group SG: retentive ball attachment (Straumann, Switzerland) with gold matrix, Group ST: retentive ball attachment (Straumann, Switzerland) with titanium spring matrix, Group IB: UNOR i-Ball with Ecco matrix (UNOR, Switzerland) and Group IMZ: IMZ-TwinPlus ball attachment with gold matrix (DENTSPLY Friadent, Germany)]. Ten samples of each system were subjected to 10,000 insertion-separation cycles. RESULTS: Results showed that all types of attachments showed wear, which led to a loss of retention force after an initial increase at the beginning of the wear simulation. Attachments with a plastic retention insert or gold matrices underwent the smallest changes in retention force. The titanium spring system showed the largest changes in retention force and a greater variation between the different cycles and specimen. This behaviour is probably caused by a large fitting tolerance of the titanium spring. CONCLUSIONS: Attachment systems which possess a male and female component of different material composition are preferable. They show smaller changes in the retention force. For retention force increase and wear compensation, an attachment system should be adjustable.

[Rehabilitation of a periodontally compromised dentition with implant-supported zirconia bridges. Case report]

Clinical aspects of reconstruction with fix prosthesis and dental implants in a patient with a history of periodontitis is shown. A successful stabilization and rehabilitation of the periodontally involved dentition can be achieved with tooth-worn crown and bridge reconstructions. From a functional and aesthetic point of view the result may not be satisfying due to mobility and overlength of the teeth and open approximal spaces. Today, dentist and patient have often to weigh if teeth shall be maintained or replaced by dental implants. Thereby, both must be aware of the fact that in complex cases long-term success and aesthetic outcome may be difficult to predict. An intense discussion with the patient on his expectations, invasive treatment, risks with regard to biologic and prosthetic aspects is mandatory and must be based on the best scientific evidence available. The present case report shows different considerations and describes a radical solution which meets the patient's needs and is based on modern CAD-CAM technology.

Endothelial cell activation leads to neutrophil transmigration as supported by the sequential roles of ICAM-2, JAM-A, and PECAM-1

Leukocyte transmigration is mediated by endothelial cell (EC) junctional molecules, but the associated mechanisms remain unclear. Here we investigate how intercellular adhesion molecule-2 (ICAM-2), junctional adhesion molecule-A (JAM-A), and platelet endothelial cell adhesion molecule (PECAM-1) mediate neutrophil transmigration in a stimulus-dependent manner (eg, as induced by interleukin-1beta [IL-1beta] but not tumor necrosis factor-alpha [TNF-alpha]), and demonstrate their ability to act in sequence. Using a cell-transfer technique, transmigration responses of wild-type and TNF-alpha p55/p75 receptor-deficient leukocytes (TNFR(-/-)) through mouse cremasteric venules were quantified by fluorescence intravital microscopy. Whereas wild-type leukocytes showed a normal transmigration response to TNF-alpha in ICAM-2(-/-), JAM-A(-/-), and PECAM-1(-/-) recipient mice, TNFR(-/-) leukocytes exhibited a reduced transmigration response. Hence, when the ability of TNF-alpha to directly stimulate neutrophils is blocked, TNF-alpha-induced neutrophil transmigration is rendered dependent on ICAM-2, JAM-A, and PECAM-1, suggesting that the stimulus-dependent role of these molecules is governed by the target cell being activated. Furthermore, analysis of the site of arrest of neutrophils in inflamed tissues from ICAM-2(-/-), JAM-A(-/-), and PECAM-1(-/-) mice demonstrated that these molecules act sequentially to mediate transmigration. Collectively, the findings provide novel insights into the mechanisms of action of key molecules implicated in leukocyte transmigration.

Aza-Michael addition of amines to activated alkenes catalyzed by Silica supported perchloric acid under a solvent-free condition

An efficient aza-Michael addition of amines to a series of ,-unsaturated ketones, carboxylic esters, nitriles and chalcones has been carried out using perchloric acid supported over silica gel (HClO4-SiO2) at room temperature in high yields under solvent-free reaction conditions.

A user supported object tracking framework for interactive video production

We present a user supported tracking framework that combines automatic tracking with extended user input to create error free tracking results that are suitable for interactive video production. The goal of our approach is to keep the necessary user input as small as possible. In our framework, the user can select between different tracking algorithms - existing ones and new ones that are described in this paper. Furthermore, the user can automatically fuse the results of different tracking algorithms with our robust fusion approach. The tracked object can be marked in more than one frame, which can significantly improve the tracking result. After tracking, the user can validate the results in an easy way, thanks to the support of a powerful interpolation technique. The tracking results are iteratively improved until the complete track has been found. After the iterative editing process the tracking result of each object is stored in an interactive video file that can be loaded by our player for interactive videos.

Combined Tooth-Implant-Supported Telescopic Prostheses in a Midterm Follow-up of > 2 Years

Purpose: The aim of this trial was to evaluate telescopic-retained prostheses on teeth and implants. Materials and Methods: Ten patients with a mean of 2.8 teeth received strategic implants to achieve triangular/quadrangular support. Survival and complication rates were estimated for telescopic abutments and prostheses. Results: After a mean observation period of > 2 years, no abutment was lost and all prostheses were in function. Complication rates were low, and maintenance services were limited to minor interventions. Conclusions: Combined tooth-implant-retained telescopic prostheses improve prosthetic support and offer successful function over a midterm period in patients with a severely reduced dentition.

Effects of Feeding Cobalt Dextro Lac (CDL) on Feedlot Performance and Carcass Value of Finishing Steers Fed Wet Corn Gluten Feed

A 192-day experiment involving 144 young Angus steers fed growing and finishing diets containing 20% corn gluten feed was conducted to evaluate feeding a soluble source of readily available cobalt. No benefits were observed in rate of gain, feed intake or carcass value by feeding the available source of cobalt.

OMA and OPA—Software-Supported Mass Spectra Analysis of Native and Modified Nucleic Acids

The platform-independent software package consisting of the oligonucleotide mass assembler (OMA) and the oligonucleotide peak analyzer (OPA) was created to support the analysis of oligonucleotide mass spectra. It calculates all theoretically possible fragments of a given input sequence and annotates it to an experimental spectrum, thus, saving a large amount of manual processing time. The software performs analysis of precursor and product ion spectra of oligonucleotides and their analogues comprising user-defined modifications of the backbone, the nucleobases, or the sugar moiety, as well as adducts with metal ions or drugs. The ability to expand the library of building blocks and to implement individual structural variations makes it extremely useful for supporting the analysis of therapeutically active compounds. The functionality of the software tool is demonstrated on the examples of a platinated doublestranded oligonucleotide and a modified RNA sequence. Experiments also reveal the unique dissociation behavior of platinated higher-order DNA structures.