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Bone maintenance after dental extraction has a significant impact on the success of future treatment. The purpose of this study was to regenerate bone by implanting an engineered porous scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in a socket created by extraction of the lower left central incisor in rabbits, utilizing the principles of tissue engineering. It involved preparation and characterization of three-dimensional porous hollow root form scaffolds consisting of a poly-L-lactic acid:polyglycolic acid composite (PLG, 50:50), using a solvent casting/compression molding/particulate leaching technique. Porosity of the scaffolds was 83.71% with good interconnectivity and uniform distribution of the various pore sizes. The degraded scaffolds maintained their porosity and form for the first 2 weeks and their mass loss continued up to 6 weeks. The scaffolds developed viscoelastic behavior under dynamic compression; yet they lost their mechanical characteristics as they degraded. The scaffolds were seeded with BMSCs and examined by scanning electron microscopy. Cell proliferation and scaffold degradation were shown up to 2 weeks in vitro. The cultivated scaffolds were implanted in empty extraction sockets immediately after tooth removal. Four weeks later, bone regeneration was evaluated histologically in the healed sockets in three experimental groups: sockets left empty, sockets that received PLG without cells, and sockets that received PLG with cells. Radiographic evaluation, performed 4 weeks later for the three experimental groups, demonstrated preservation of alveolar bone walls in the extraction sockets that received PLG with cells as compared with the other two groups. The bone density profile for the healed sockets confirmed both histological and radiographic findings. The results of this study show promise in the area of dentoalveolar surgery, yet longitudinal studies under variable clinical situations would encourage the current application.

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Purpose In this study, we aimed to determine the regenerative and antimicrobial impact of the electrospun nanofiber mats, with/without silver nanoparticles (AgNPs), on full-thickness skin wounds in rabbits. Methods Polyvinyl alcohol was combined with gelatin to provide biocompatible electrospun binary nanofiber mats. AgNPs were added to the polyvinyl alcohol/gelatin mixture to obtain ternary nanofiber-AgNPs mats. Binary and ternary nanofiber mats were characterized by scanning electron microscopy before being applied as wound dressings in vivo. Subsequently, wound healing was evaluated. Results Both nanofiber/nanofiber-AgNPs mats improved the microscopic quality of the healed skin, albeit without obvious acceleration of the healing rate. As well, both types of nanofiber mats were able to combat microbial invasion into the wound bed. Conclusions Both binary polyvinyl alcohol/gelatin and ternary polyvinyl alcohol/gelatin/AgNPs nanofiber mats developed in the present study depicted similar regenerative and antimicrobial potential when applied as full-thickness wound dressing. However, in comparison to the binary nanofiber mats, no obvious synergistic effect was observed after loading nanofibers with AgNPs.

A survey study was done during the period between September 2010 and December 2012 on 2580 Friesian cows and heifers distributed in four armed forces farms.This work revealed that, teat wounds represent the higher acquired teat affections (28.16 %) while teat papilloma represents the lowest affection (1.65 %). The supernumerary teat represents the higher congenital teat abnormalities (36.8 %) while the lower was incompetent teat (1.5 %).The present study revealed that the prevalence of acquired teat affections were in November, December, January, and February, whenever the weather is cold and rainy and stables are muddy and the accidental injuries during milking, feeding or even laying were predominant and predictable.