Dental Pulp Stem Cells and Tissue Engineering Strategies for Clinical Application on Odontoiatric Field

Recent advances in tissue engineering have drawn scientists to test the possibility of tooth engineering and regeneration. Tooth regeneration is normally referred to as the regeneration of the entire tooth or root that can be integrated into the jaw bone. This technology is still at its infancy and when it matures, it may be used to restore missing teeth and replace artificial dental implants When the tooth is damaged but still in a reparable condition, regeneration of parts of the tooth structure can prevent or delay the loss of the whole tooth. To engineer and regenerate a whole tooth, the cell source, tissue engineering strategies and specific scaffolds needed to be correct choose. Indeed, for example, to repair partly lost tooth tissues such as PDL, dentin, and pulp, one or two particular types of dental stem cells may be sufficient to fulfill the need. In light of such considerations, aim of the present chapter is to define the main strategies to isolate dental pulp stem cells, their characterisation and differentiation, tissue enngineering strategies and clinical applications for the creation of artificial tissue useful in odontoiatric field

Platform switching on wide-diameter external hex implants a finite element analysis

Objectives: The objective of this work was to use finite element analysis to compare the effect of forces coming to bear on abutments 4.1 or 5.0 mm in diameter connected to a 5.0 mm implant (i.e. with or without platform swit - ching). Study design: A 3D CAD model of a 5 x 11.5 mm external hex implant was developed, complete with a connection screw and either of two abutments, one 4.1 and the other 5 mm in diameter, to assess the influence of two loading conditions, i.e. 200 N loaded either axially or off center on the top of the abutment. Results and conclusions: In the symmetrically loaded models, greater stresses were transmitted to the bone in the area below the neck of the implant in the case of the wider-diameter abutment. When the narrower abutment was considered, the stress lines remained confined to the metal and were transferred to the bone in a more distal position. When the stresses in the bone where compared under non-symmetrical loading of the larger- and smaller-diameter abutments, the stresses reached lower values in the latter case. These findings indicate that platform switching (i.e. coupling a 4.1 mm abutment with a 5 mm implant) achieves a better, more even distribution of the peri-implant stresses deriving from simulated occlusal loads on the bone margins

Silver Nanoparticles in Alveolar Bone Surgery Devices

Silver (Ag) ions have well-known antimicrobial properties and have been applied as nanostrategies in many medical and surgical fields, including dentistry. The use of silver nanoparticles (Ag NPs) may be an option for reducing bacterial adhesion to dental implant surfaces and preventing biofilm formation, containing the risk of peri-implant infections. Modifying the structure or surface of bone grafts and membranes with Ag NPs may also prevent the risk of contamination and infection that are common when alveolar bone augmentation techniques are used. On the other hand, Ag NPs have revealed some toxic effects on cellsin vitroandin vivoin animal studies. In this setting, the aim of the present paper is to summarize the principle behind Ag NP-based devices and their clinical applications in alveolar bone and dental implant surgery

Correction: Nanostructured Biomaterials for Tissue Engineered Bone Tissue Reconstruction. Int. J. Mol. Sci. 2012, 13, 737–757

We would like to change the authors’ names and E-Mail addresses on Page 737 of Article [1] from: [...

Nanostructured Biomaterials for Tissue Engineered Bone Tissue Reconstruction

Bone tissue engineering strategies are emerging as attractive alternatives to autografts and allografts in bone tissue reconstruction, in particular thanks to their association with nanotechnologies. Nanostructured biomaterials, indeed, mimic the extracellular matrix (ECM) of the natural bone, creating an artificial microenvironment that promotes cell adhesion, proliferation and differentiation. At the same time, the possibility to easily isolate mesenchymal stem cells (MSCs) from different adult tissues together with their multi-lineage differentiation potential makes them an interesting tool in the field of bone tissue engineering. This review gives an overview of the most promising nanostructured biomaterials, used alone or in combination with MSCs, which could in future be employed as bone substitutes. Recent works indicate that composite scaffolds made of ceramics/metals or ceramics/polymers are undoubtedly more effective than the single counterparts in terms of osteoconductivity, osteogenicity and osteoinductivity. A better understanding of the interactions between MSCs and nanostructured biomaterials will surely contribute to the progress of bone tissue engineering

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

Sintesi e caratterizzazione di complessi di palladio e platino con leganti dicarbenici macrociclici

NHC dicarbene complexes of metals of group 10 and 11 have an extended and studied chemistry both on structural aspect and catalytic properties. The first part of this work was about synthesis and characterization of some new platinum(II) and gold(I) complexes bearing macrocyclic ligands and the subsequently study of the reactivity of platinum(II) and palladium(II) complexes; since palladium(II) complexes was already successfully used as catalysts in copper-free Sonogashira reaction, resulting more active than the more classical carbene complexes reported in literature, in the second part a catalytic test was studied with a confront purpose for the qualitative determination of the catalytic efficiency of such compounds

Commons in Alpine Lombardy. The case of Brescia

Il contributo affronta, anche sulla base di una documentazione originale, un caso significativo di governo del territorio e di gestione dei beni comuni nell\u2019area alpina della Lombardia e di Brescia. Tra le diverse forme che il fenomeno ha conosciuto, viene presa in esame la \u201cVicinia\u201d della Valle Camonica, dall\u2019et\ue0 veneta a quella contemporanea, analizzando in particolare il momento di svolta rappresentato dalla Rivoluzione francese e dai suoi esiti sul piano locale. Qui se ne ripercorrono le vicende, dalla legislazione cisalpina \u2013 in un quadro culturale e politico che mette in campo varie ipotesi di soluzione \u2013 all\u2019approdo uniformante del decreto del 1806 che porta alla liquidazione dei beni delle \u201cVicinie\u201d stesse, dopo una discussione al Consiglio di Stato che pure non era stata priva di aperture. Dal confronto con la storiografia \u2013 dai classici ottocenteschi al dibattito recente sui Commons e agli studi su analoghe esperienze \u2013 emergono le peculiarit\ue0 di un sistema rivolto ad assicurare alle terre alte un equilibrio, poi messo in crisi dai nuovi scenari della modernit\ue0 politica ed economica. L\u2019et\ue0 napoleonica segna appunto la fine, per l\u2019intero mondo alpino e in generale per la montagna europea, delle antiche autonomie delle valli e delle singole comunit\ue0, autonomie non solo amministrative, ma anche sociali nel senso pi\uf9 ampio, interrotte dal modello di Stato che trova nella legislazione napoleonica il suo momento di affermazione, mutando radicalmente il precedente sistema di rapporti con l\u2019insieme dei corpi intermedi. Si tratta di un grande fenomeno di trasformazione che ha accompagnato la nascita dello Stato moderno suscitando resistenze e contraddizioni, pur facendo leva su problemi interni dell'assetto precedente. Le \u201cVicinie\u201d erano state appunto segnate dai contrasti prima fra "originari" e "forestieri" e poi fra "antichi" e "nuovi originari", dispute che solo a fatica il governo veneto era riuscito a contenere, ma quella sorta democrazia alpina fatta di assemblee al tocco di campana, certo con molti limiti, era stata in grado di assicurare un uso comune delle risorse, una sostenibilit\ue0 ambientale e una rete di integrazione sociale.The history of the Alps is a very interesting example to examine the government of commons from the early modern period to the nineteenth century, in particular in the Brescia area but also, in similar forms, in mountain territories of the Venetian Republic and Northern Italy. In the ancient social organization, this government was entrusted to an assembly of each village (called vicinia) and formed by the \u201coriginal\u201d inhabitants (originari), i.e. members of the families living from time immemorial, and \u201cnew original\u201d inhabitants (nuovi originari), later admitted to the assembly. Starting from Germanists and Marxist analysis, historical studies on village communities have shown that this system was not a primitive communism, but a relationship between public and private spheres, in a difficult but effective balance of power. The aim of this work, within the framework described, is to understand how the vicinia managed the common resources with a great capacity to protect the environment and guarantee important elements of democracy, then compromised by the economic modernization