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A scheme for the controlled generation of single traveling sine- Gordon breathers in a long Josephson junction is described. In the presence of dissipation, a direct current source, and thermal fluctuations, the theoretical analysis shows that, through the nonlinear supratransmission effect, tailored magnetic pulses at the junction’s edge can effectively yield breather modes only.

The agenesis of the upper lateral incisor is one of the most frequent aesthetic-functional problems in dentistry. The reported case concerns a 49 years old male patient with bilateral agenesis of teeth 1.2-2.2 and a root stump of tooth 5.2 temporarily rehabilitated through a Maryland bridge. Without orthodontic treatment, the only solution for implant-prosthetic rehabilitation of tooth 1.2 results therefore in the use of a 2.9 mm diameter implant. The clinical and radiographic control of the implant and the gingival stability at a distance of 1 year gives a positive result both clinically and radiographically. The use of the implant with a 2.9 mm diameter is therefore indicated in extreme cases of limited bone availability.

We report a case of a 37-year-old caucasian woman presenting a 1 cm pinkish nodular asymptomatic lesion of the hard palate, slowly growing in the last years. The lesion underwent to biopsy. Histological analysis showed the nevus tissue layered under a continuous squamous epithelium. The stroma contained nests of medium-sized round cells, with regular monomorphous nuclei. The nevus cells were immunohistochemically positive for S-100 protein, while melanin, visualized by Masson-Fontana silver staining, was absent. Therefore a diagnosis of non pigmented melanocytic nevus was formulated. Because of its rarity and to avoid any risk of malignant transformation, a surgical treatment with wide excision was chosen; the surgical wound was previously covered with a membrane of fibrin and autologous platelets, and subsequently sutured, resulting in a total heal. This procedure seems to be the most reliable to approach melanocytic lesions of the oral cavity. Clinical diagnosis of non-pigmented nevi, either flat or protruding, is difficult, because the nevus shows a pinkish colour that is indistinguishable from that of the surrounding mucosa. Moreover, attention is required when similar clinical evidence occurs, because the localization inside the oral cavity may offer several problems of differential diagnosis.

Peri-implantitis is an inflammatory process involving peri-implant bone. Angiogenesis is critical for the development, remodeling and healing of bone. Vascular Endothelial Growth Factor (VEGF) is a glycoprotein that induces endothelial cell proliferation, angiogenesis and capillary permeability. VEGF is expressed in a variety of highly vascularized tissues and seems to be a prerequisite for tumor growth and invasion. VEGF takes part in bone cell differentiation and by promoting angiogenesis at the site of bone formation. Aim of the present study was an evaluation of VEGF mRNA in bone around healthy and failing dental implants. Twenty patients participated in this study. Twenty bone biopsies were obtained, 10 at second-stage surgery from bone covering the healing screws (control), and 10 from implants presenting the typical signs and symptoms for peri-implantitis lesions (test). VEGF mRNA levels were not present in any of the controls, while it was identified in all tissues obtained from test implants. The difference was statistically significant (p < 0.05). Our results point to the fact that VEGF may be important in the regulation of tissue healing and bone remodeling in the peri-implantitis lesions because VEGF has been reported to play a role in the formation and attraction of osteoclasts, and osteoclasts have been shown to be a prominent feature of the peri-implantitis lesions.

Metal ions accumulate inside the epithelial cells of the oral mucosa and damage the DNA. The aim of this study was to analyze whether DNA damage and/or apoptosis also occurs after a short-term exposure to the metals of fixed orthodontic appliances. 23 subjects were enrolled in the test group and 8 patients in the control group. Analyses performed on samples of oral mucosa were cell count, cellular viability, quantification of intracellular metal concentration, comet and micronuclei tests and quantification of intracellular Glutathione (GSH). The obtained results indicated that orthodontic appliances release metal ions, especially chromium, that cause inflammatory processes leading to DNA damages. These phenomenon are visible only after 30 days from application of fixed orthodontic appliances.

Patients in treatment with rapid palatal expander (RPE) require professional assistance and more meticulous instructions on oral hygiene, since this appliance predisposes to gingivitis and caries. The aim of this work is to analyse the variability of the oral microbial flora found in patients in treatment with RPE with occlusal acrylic splint. It was also investigated whether the association of an antimicrobial mouthwash was useful during orthodontic treatment or whether regular and specific home oral hygiene manoeuvres were sufficient to maintain a good plaque control. The last goal was to highlight which of the different mouthwashes was the most effective in reducing the bacterial load. The patients were divided into 3 test groups and each one of them had a different mouthwash (chlorhexidine and sodium fluoride, fluorine, essential oils) randomly assigned. There was also a control group. Plaque samples were analysed through cultural analysis and PCR from T0 to T4 (8 months). Chlorhexidine mouthwash reduces the bacterial count by 96.08%, the fluorine by 94.50% and the essential oils by 95.74%. The results of the three mouthwashes are superimposable and although chlorhexidine gives the highest rate of bacteria reduction, its side effects lead the authors to prefer the essential oils.