626 research outputs found

    Supersolid behaviour of a dipolar Bose-Einstein condensate confined in a tube

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    Motivated by a recent experiment [L.Chomaz et al., Nature Physics 14, 442 (2018)], we perform numerical simulations of a dipolar Bose-Einstein Condensate (BEC) in a tubular confinement at T=0 within Density Functional Theory, where the beyond-mean-field correction to the ground state energy is included in the Local Density Approximation. We study the excitation spectrum of the system by solving the corresponding Bogoliubov-de Gennes equations. The calculated spectrum shows a roton minimum, and the roton gap decreases by reducing the effective scattering length. As the roton gap disappears, the system spontaneously develops in its ground-state a periodic, linear structure formed by denser clusters of atomic dipoles immersed in a dilute superfluid background. This structure shows the hallmarks of a supersolid system, i.e. (i) a finite non-classical translational inertia along the tube axis and (ii) the appearance, besides the phonon mode, of the Nambu-Goldstone gapless mode corresponding to phase fluctuations, and related to the spontaneous breaking of the gauge symmetry. A further decrease in the scattering length eventually leads to the formation of a periodic linear array of self-bound droplets.Comment: 5 pages, 4 figures (version accepted for publication in PRA Rapid Communications

    Implant survival after surgical treatment of peri‐implantitis lesions by means of deproteinized bovine bone mineral with 10% collagen: 10‐year results from a prospective study

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    ObjectivesTo evaluate the 10‐year outcomes of a regenerative surgical treatment of single peri‐implantitis intrabony defects, by means of deproteinized bovine bone mineral with 10% collagen (DBBMC).Material and MethodsThe original population consisted of 26 patients with one crater‐like defect, around either SLA or TPS dental implants, with a probing depth ≥6 mm and no implant mobility. After debridement and surface decontamination, the defects were filled with DBBMC. Subsequently, patients were placed in an individualized supportive peri‐implant/periodontal therapy (SPT) program.ResultsFourteen patients (eight SLA and six TPS) reached the 10‐year examination. The overall implant survival rate was 67%, 80% for the SLA, and 55% for the TPS implants. During SPT, five patients were lost to follow‐up, eight patients needed additional antibiotic and/or surgical therapy, and seven patients had the implant removed. PD was reduced from 6.6 ± 1.3 to 3.2 ± 0.7 mm in SLA and from 7.2 ± 1.5 to 3.4 ± 0.6 mm in TPS. BOP decreased from 75.0 ± 31.2% to 7.5 ± 12.1% (SLA) and from 90.0 ± 12.9% to 30.0 ± 19.7% (TPS). Treatment success was found in 5 of the 12 SLA (42%) and in 4 of the 14 TPS (29%).ConclusionsThe proposed reconstructive treatment, followed by SPT, was able to maintain in function the majority of SLA implants, although the overall treatment success was limited and many of TPS implants were removed. Therefore, the decision to treat implants affected by peri‐implantitis should be based on several factors, including surface characteristics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156127/3/clr13628-sup-0001-Supinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156127/2/clr13628_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156127/1/clr13628.pd

    Minimal invasiveness in the reconstructive treatment of peri-implantitis defects.

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    Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, clinically characterized by increased peri-implant probing pocket depth and progressive loss of supporting bone. Consequently, to arrest further disease progression and to increase the chance to obtain re-osseointegration, surgical reconstructive procedures have been adopted. In particular, following a paradigm gathered from periodontal therapy, recent protocols have underlined the importance of a minimally invasive approach to optimize the outcomes of therapy while minimizing the risks of postoperative complications. The present review summarizes the level of evidence on the surgical reconstructive protocols focusing on the new approaches aiming to minimize surgical trauma and patients' postoperative discomfort, underlining the pros and cons of each treatment modality

    Perioperative and anesthetic deaths: toxicological and medico legal aspects

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    Background: Anesthesia has become safer during decades, though there is still a preventable mortality; the complexity of medical and surgical interventions, increasingly older and sicker patients, has created a host of new hazards in anesthesiology. In this paper, some of these perioperative (PO) fatal adverse events are investigated in terms of health responsibility. Selective literature research in several data bases, concerning perioperative and anesthetic deaths and medical responsibility, was performed. Main text: A generally accepted definition of the anesthesia and perioperatory-related death still remains one of the major concerns in forensic pathology, and the terms “operative deaths” and “anesthetic deaths” are usually applied inaccurately within the medico-legal literature. Such events involve comprehensively PO fatalities and allow for subtle separation of natural and unnatural death, at least from the prospective of forensic pathology. Iatrogenic deaths in this field can be separated into some major categories, as attributable to previous patient’s unfavorable conditions or depending from surgical procedure per se (such as PO cardiac and cerebrovascular events). In this review, the authors carried out syntheses of specific research areas regarding epidemiology, complications of general and spinal anesthetic, failure in airway management and patient’s circulatory homeostasis, and adverse drugs reactions; analysis considering the challenge of anesthetic-related mortality, epidemiology and classifications, by indicating causal chain of death, in respect of both contributing and associated anesthetic and surgery facts. Conclusions: Perioperative quality control programs and its relevance for medico-legal evaluation are emphasized as, although mortality rates have decreased worldwide over the last decades, however, preventable drug-related deaths still happen. Such fatal events have to be considered within the field of forensic pathology experts, with regard of malpractice claims, to implement a strategy for preventing potentially fatal complications

    Clinical outcomes of dental implants in patients with and without history of periodontitis: A 20-year prospective study.

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    AIM To present the 20-year clinical outcomes of tissue-level implants in partially edentulous patients previously treated for periodontitis and in periodontally healthy patients (PHP). MATERIAL AND METHODS The original population consisted of 149 partially edentulous patients consecutively enrolled in a private specialist practice and divided into three groups: PHP, moderately periodontally compromised patients (mPCP) and severely PCP (sPCP). After successful completion of periodontal/implant therapy, patients were enrolled in an individualized supportive periodontal care (SPC) programme. RESULTS Eighty-four patients rehabilitated with 172 implants reached the 20-year examination. During the observation time, 12 implants were removed (i.e., 11 due to biological complications and 1 due to implant fracture), leading to an overall implant survival rate of 93% (i.e., 94.9% for PHP, 91.8% for mPCP and 93.1% for sPCP [p = .29]). At 20 years, PCP compliant with SPC did not present with significantly higher odds of implant loss compared with PHP compliant with SPC (p > .05). Conversely, PCP not compliant with SPC experienced implant loss with odds ratio of 14.59 (1.30-164.29, p = .03). CONCLUSIONS Tissue-level implants, placed after comprehensive periodontal therapy and SPC, yield favourable long-term results. However, patients with a history of periodontitis and non-compliant with SPC are at higher risk of biological complications and implant loss

    Long-term treatment outcomes of single maxillary buccal peri-implant soft tissue dehiscences: A 10-year prospective study.

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    INTRODUCTION To evaluate the 10-year clinical outcomes following surgical treatment of shallow isolated peri-implant soft-tissue dehiscences (PSTD) at single tissue level dental implants. METHODS The baseline population included 16 patients (16 implants) displaying an isolated peri-implant maxillary buccal soft-tissue dehiscence. The recipient bed was prepared with a minimally-invasive split-thickness flap limited to the buccal aspect to stabilize the tuberosity connective tissue graft (CTG) onto the periosteum. At the end of treatment, patients were enrolled in an individualized supportive peri-implant care (SPC) program. The aesthetic outcome was evaluated on photographs by three clinicians using a visual analog scale (VAS). RESULTS SPC during the 10-years proceeded uneventfully in all patients. A total of 12 patients completed the 10-year examination, as 3 patients dropped-out and 1 implant was lost. Complete PSTD coverage was obtained at 7 implant sites (i.e., 58%) while the mean PSTD coverage amounted to 89.6% ± 17.1% without statistically significant differences between 1 and 10 years (p > 0.05). Stable peri-implant parameters (i.e., PD and BoP) and full-mouth scores (i.e., FMPS, FMBS) were recorded throughout the observation period (p > 0.05). The aesthetic improvements obtained in the short-term were maintained up to 10 years. CONCLUSION Within their limits, the present results indicate that the proposed surgical technique is a simple and reliable treatment option for the treatment of single maxillary buccal PSTDs in selected cases with positive results up to 10 years in patients under regular SPC (NCT04983758-this clinical trial was not registered prior to participant recruitment)
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