Temporal sequence of hard and soft tissue healing around titanium dental implants.

The objective of the present review was to summarize the evidence available on the temporal sequence of hard and soft tissue healing around titanium dental implants in animal models and in humans. A search was undertaken to find animal and human studies reporting on the temporal dynamics of hard and soft tissue integration of titanium dental implants. Moreover, the influence of implant surface roughness and chemistry on the molecular mechanisms associated with osseointegration was also investigated. The findings indicated that the integration of titanium dental implants into hard and soft tissue represents the result of a complex cascade of biological events initiated by the surgical intervention. Implant placement into alveolar bone induces a cascade of healing events starting with clot formation and continuing with the maturation of bone in contact with the implant surface. From a genetic point of view, osseointegration is associated with a decrease in inflammation and an increase in osteogenesis-, angiogenesis- and neurogenesis-associated gene expression during the early stages of wound healing. The attachment and maturation of the soft tissue complex (i.e. epithelium and connective tissue) to implants becomes established 6-8 weeks following surgery. Based on the findings of the present review it can be concluded that improved understanding of the mechanisms associated with osseointegration will provide leads and targets for strategies aimed at enhancing the clinical performance of titanium dental implants.

In vivo degradation of magnesium plate/screw osteosynthesis implant systems: Soft and hard tissue response in a calvarial model in miniature pigs.

Biodegradable magnesium plate/screw osteosynthesis systems were implanted on the frontal bone of adult miniature pigs. The chosen implant geometries were based on existing titanium systems used for the treatment of facial fractures. The aim of this study was to evaluate the in vivo degradation and tissue response of the magnesium alloy WE43 with and without a plasma electrolytic surface coating. Of 14 animals, 6 received magnesium implants with surface modification (coated), 6 without surface modification (uncoated), and 2 titanium implants. Radiological examination of the skull was performed at 1, 4, and 8 weeks post-implantation. After euthanasia at 12 and 24 weeks, X-ray, computed tomography, and microfocus computed tomography analyses and histological and histomorphological examinations of the bone/implant blocks were performed. The results showed a good tolerance of the plate/screw system without wound healing disturbance. In the radiological examination, gas pocket formation was found mainly around the uncoated plates 4 weeks after surgery. The micro-CT and histological analyses showed significantly lower corrosion rates and increased bone density and bone implant contact area around the coated screws compared to the uncoated screws at both endpoints. This study shows promising results for the further development of coated magnesium implants for the osteosynthesis of the facial skeleton.

Empowering Teachers as Leaders: A Hard Sell

Despite emphasis on preparing teachers as leaders, teacher educators realize that the transition of classroom practitioners into school leaders is fraught with many obstacles. This session addresses some of these obstacles, describes strategies and opportunities that we have used in our graduate master’s degree programs for teachers that support professionals as they make this change. The session will present evidence on the results of our efforts in terms of teachers’ performances within their programs and in the field after they graduate.

Johannes Daniel Hard, Hüftbild

Signatur des Originals: S 36/G03135

Why the Village is so Hard to Find: Challenging Ourselves, Transforming Our Helping Systems

Keynote address presented by Roger Friedman, PhD, LCSW at the Family Preservation Institute Annual Conference, San Antonio, Texas, September 9, 2004. Looking at Language and Concepts Looking closely at certain language that we use helps us understand how we think about our work and our world—and ultimately, it helps us understand ourselves better. The term "village " as used in the title of the paper and in many of our professional conversations is worthy of such an inquiry

Succession of benthic hard-bottom communities in the shallow sublitoral of Comau Fjord, Chile

Succession was already studied over decades. The present thesis investigated the succession on hard substrate at two different study sites within the fjord Comau, Chile. Nine plates were installed at both sites (mouth of fjord and inner fjord) and photographed over three years. Additionally the natural community was recorded and a ground truthing was carried out to verify the analyzed species. Respectively at both sites over 50 different species were identified. Abundance data decreased with only one exception continuously, whereas the percentage cover increased. But the communities on the recruitment plates do still not reach the community structure of the natural environment. The present data showed that the hard-bottom succession in the fjord Comau is best described by the TOLERANCE MODEL (Connell & Slatyer, 1977). An important species of the natural community is the stony coral Desmophyllum dianthus, which normally (outside the fjord) grows beneath 1000 m water depth. The results of this work indicate that the mature community is not reached after 36 months.