BackgroundThree millimeter is considered as the minimum distance to obtain soft and bone tissue stability in case of adjacent implants. The possibility to preserve peri‐implant bone level using a platform switching connection has questioned this concept.PurposeThe study evaluates soft tissue maintenance and marginal bone stability around implants, placed at 2 or 3 mm of distance.Materials and methodsThirty patients received two immediately loaded implants either at 2‐mm (test) or at 3‐mm (control) of distance in the premolar area. Soft tissue esthetics (papilla height and fill, keratinized tissue, recession) and radiographic peri‐implant bone level changes were measured at 3, 6, and 12 months.ResultsNo significant differences between the two groups were detected neither for all soft tissue esthetic outcomes nor for bone level modifications up to 12 months.ConclusionThe results suggested that up to 12 months post‐loading, both 2‐ and 3‐mm inter‐distance platform‐switched implants in healed site, supported adequate esthetic outcomes and peri‐implant bone stability.

The use of alloplastic materials in periodontal regenerative therapies is limited by their incapacity to establish a dynamic dialog with the surrounding milieu. The aim of the present study was to control biomaterial surface bioactivity by introducing aptamers to induce the selective adsorption of fibronectin from blood, thus promoting platelets activation in vitro and bone regeneration in vivo. A hyaluronic acid/polyethyleneglycole-based hydrogel was enriched with aptamers selected for recognizing and binding fibronectin. In vitro, the capacity of constructs to support osteoblast adhesion, as well as platelets aggregation and activation was assessed by chemiluminescence within 24 h. Matrices were then evaluated in a rat periodontal defect to assess their regenerative potential by microcomputed tomography (µCT) and their osteogenic capacity by Luminex assay 5, 15 and 30 d postoperatively. Aptamers were found to confer matrices the capacity of sustaining firm cell adhesion (p = 0.0377) and to promote platelets activation (p = 0.0442). In vivo, aptamers promoted new bone formation 30 d post-operatively (p < 0.001) by enhancing osteoblastic lineage commitment maturation. Aptamers are a viable surface modification, which confers alloplastic materials the potential capacity to orchestrate blood clot formation, thus controlling bone healing.

This article explores the relations between agricultural production, international migration, wage labour and processes of differentiation among peasant households. It does so based on the analysis of the ejido Jesús María in the northeast of the state of Guanajuato, Central Mexico. The history of this ejido and how Mexican neoliberal policies led to increased levels of migration and proletarianization since at least the early 1990s is presented. Then, it presents how in this context the production of asparagus for agro‐export developed on the irrigated lands of this ejido, showing that this process went hand in hand with social differentiation and important changes in the distribution of land and water. Then, it presents the results of a household and production survey that shows that most peasant households combine agricultural production with local urban and rural wage labour, migration, remittances and/or other economic activities. Households that can live from agriculture alone have had important capital investments in agricultural production coming from international migration and remittances. Based on these results, it argues that, as rural communities become increasingly dependent on external ‘urban/global’ capital, the rural/urban divide has become increasingly permeable with important consequences for peasant economies and related social differentiation processes.

Prostaglandin signaling affects the activation of Wnt canonical pathway in osteoblastic and mesenchymal cells on microstructured surfaces.

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