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This article proposes a digital procedure to create the emergence profile of prosthetic crowns for teeth prepared with the Vertical Edgeless Preparation (VEP) technique. This technique extends the tooth preparation below the gingival margin on the root surface of teeth with reduced periodontal attachment. The tooth prepared according to this technique does not present a defined prosthetic margin or the relative finishing line. Still, it shows an edgeless axial wall that emerges from the gingival sulcus. The digital procedure for creating a prosthetic emergence profile, although representing a novelty in absolute terms, is based on traditional concepts, as they have been known and described in the literature for a long time. This article will explain and review the various clinical and laboratory steps necessary to produce, through an entirely digital procedure, a fixed partial denture composed of three zirconia elements, which are going to be subsequently veneered in a traditional way on the vestibular side to improve the esthetic appearance. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this case report is to show an effective and minimally invasive way to treat dentition which suffered the effects of severe acid erosion. Case Report: The patient was a 51-year-old man who presented with complaints about the appearance of his teeth. The patient reported he had been suffering from gastroesophageal reflux disease for 7 years and that he had not undergone any dental treatment except for 3 direct restorations performed 15 years before. Clinical and radiographical examinations showed a severely worn dentition presenting the typical pattern of acid erosion and a concrete loss in vertical dimension of occlusion (VDO). All teeth responded positively to the dental pulp vitality test, so it was decided to perform minimally invasive full-mouth restorations with lithium disilicate veneers to restore form and function of the dentition. First, the increase of VDO was determined. Then the Digital Smile Design (DSD) protocol was used to create a preview of the new shape and dimension of the teeth, produce a wax-up of the restored dentition, and two silicon indexes to create the mock-up. Subsequently, the mock-up on the worn teeth was printed and phonetic tests were performed. Since the patient was satisfied with the esthetics and function of the new dentition, we proceeded with our therapy plan. We performed a mock-up--driven preparation technique which resulted in minimally invasive preparations, and took VPS impressions for lithium disilicate veneers that were cemented in different appointments starting from the posterior areas, and carefully following the adhesive cementation protocol. Results: The rehabilitation successfully restored form and function of the dentition. At the 6-month recall, the patient was satisfied and the veneers were perfectly integrated with the surrounding soft tissues. Conclusion: In case of severe acid erosion, the presented protocol represents a viable, predictable, and minimally invasive therapeutic option. [ABSTRACT FROM AUTHOR]

The research in the field of biomaterials has largely focused on the development of methods to enhance their bioactivity. Adopted strategies include chemical-physical approaches, but mainly the use of monoclonal antibodies, which confer the system target specificity. However, antibodies are marred by numerous issues, such as low physical-chemical stability or the risk of inducing immunological responses in the host, which often make their use difficult. Aptamers - a new class of molecules discovered in the early nineties - are small oligonucleotides, or in some cases peptides, and have been proposed to rival antibodies in biomedicine, countering at least some of the antibody-related drawbacks. The aim of this review is to provide a background to nucleic acid aptamers and to explore their novel applications. In addition to providing brief overview of their therapeutics applications, here we have assessed the methods that employ aptamers to improve the bioactivity of biomaterials, in particular, those that enhance targeting properties of drug delivery systems for chemotherapy, and those ameliorating scaffold biocompatibility for tissue engineering approaches. [ABSTRACT FROM AUTHOR]

Background: Rough surface topography enhances the activation of Wnt canonical signaling, a pathway required for osteoblast differentiation. The present study investigated the effects of the modulation of prostaglandin E2 (PGE2) signaling on osteoblastic differentiation on titanium surfaces for endosseous implants with different topographies. Methods: C2C12 cells were plated on polished or acid-etched/sand-blasted (SLA) titanium discs and stimulated with 1 µM PGE2 or 100 nM cyclooxygenase inhibitor indomethacin. Activation of Wnt canonical signaling was measured with a reporter system. Gene expression was measured in the same cell system by real-time polymerase chain reaction (RT-PCR). Osteoblastic MC3T3 cells were then plated on polished or SLA titanium discs with or without indomethacin, and their proliferation and the expression of osteoblast-specific genes was assessed by RT-PCR. Cell morphology was furthermore studied on SEM, and cell adhesion was assessed by fluorescent labeling of focal adhesion. Results: PGE2 decreased Wnt signaling stimulation in cells growing on polished or SLA surfaces, while indomethacin increased the expression of Wnt target genes in C2C12 and MC3T3 cells, by reporter assay. Moreover, indomethacin increased the expression of early differentiation marker alkaline phosphatase in MC3T3 cells on polished discs and of late marker osteocalcin in cells on SLA titanium. Conclusions: Prostaglandin signaling affects the activation of Wnt canonical pathway in osteoblastic and mesenchymal cells on microstructured surfaces. [ABSTRACT FROM AUTHOR]

Aim: The aim of the present study was to investigate the efficacy of environmental scanning electron microscopy (ESEM), in low vacuum mode (LV-ESEM) and in wet mode (wet-ESEM) in the assessment of cell-material interactions., Methods: Mouse calvaria MC3T3 cells (ATCC) were seeded on commercially pure machined titanium discs of 10 mm diameter in Dulbecco modified MEM, 10% Fetal Bovine Serum, 1% Penicillin and Streptomycin and 1% Glutamine. Samples were then processed for microscope observation by rinse in Phosphate Buffer saline and fixation in 4.5% Glutaraldehyde. Samples were then rinsed in Sodium Cacodylate buffer and observed or dehydrated in alcohol prior to LV-ESEM observation. Fresh samples in 0.9% NaCl solution were observed in wet- ESEM., Results: No significant loss of detail was observed when dehydrated or non dehydrated samples were analysed at LV-ESEM.The observation of fresh samples in wet-ESEM however proved difficult for the need to eliminate water which forms a layer covering the sample, thus hiding cell surface details. When reducing the vapor pressure in the chamber, the layer evaporated and NaCl immediately started to precipitate and cells collapsed, thus no further investigation was possible., Conclusions: The use of low vacuum-ESEM after cell fixation, but without dehydration or gold sputter coating proved a viable alternative to traditional high vacuum SEM observation.