Non-linear frequency and amplitude modulation of a nano-contact spin torque oscillator

We study the current controlled modulation of a nano-contact spin torque oscillator. Three principally different cases of frequency non-linearity ($d^{2}f/dI^{2}_{dc}$ being zero, positive, and negative) are investigated. Standard non-linear frequency modulation theory is able to accurately describe the frequency shifts during modulation. However, the power of the modulated sidebands only agrees with calculations based on a recent theory of combined non-linear frequency and amplitude modulation.Comment: 4 pages, 4 figure

Cost-effectiveness analysis of 3-D computerized tomography colonography versus optical colonoscopy for imaging symptomatic gastroenterology patients.

BACKGROUND: When symptomatic gastroenterology patients have an indication for colonic imaging, clinicians have a choice between optical colonoscopy (OC) and computerized tomography colonography with three-dimensional reconstruction (3-D CTC). 3-D CTC provides a minimally invasive and rapid evaluation of the entire colon, and it can be an efficient modality for diagnosing symptoms. It allows for a more targeted use of OC, which is associated with a higher risk of major adverse events and higher procedural costs. A case can be made for 3-D CTC as a primary test for colonic imaging followed if necessary by targeted therapeutic OC; however, the relative long-term costs and benefits of introducing 3-D CTC as a first-line investigation are unknown. AIM: The aim of this study was to assess the cost effectiveness of 3-D CTC versus OC for colonic imaging of symptomatic gastroenterology patients in the UK NHS. METHODS: We used a Markov model to follow a cohort of 100,000 symptomatic gastroenterology patients, aged 50 years or older, and estimate the expected lifetime outcomes, life years (LYs) and quality-adjusted life years (QALYs), and costs (£, 2010-2011) associated with 3-D CTC and OC. Sensitivity analyses were performed to assess the robustness of the base-case cost-effectiveness results to variation in input parameters and methodological assumptions. RESULTS: 3D-CTC provided a similar number of LYs (7.737 vs 7.739) and QALYs (7.013 vs 7.018) per individual compared with OC, and it was associated with substantially lower mean costs per patient (£467 vs £583), leading to a positive incremental net benefit. After accounting for the overall uncertainty, the probability of 3-D CTC being cost effective was around 60 %, at typical willingness-to-pay values of £20,000-£30,000 per QALY gained. CONCLUSION: 3-D CTC is a cost-saving and cost-effective option for colonic imaging of symptomatic gastroenterology patients compared with OC

Trans-nasal endoscopic marsupialization of a voluminous radicular cyst involving maxillary sinus and nasal cavity: A case report and a literature review on this surgical approach

The treatment of a huge cystic lesion in the upper jaw involving the respiratory cavities may result challenging. A traditional oral approach entails patient discomfort and may have negative aesthetic implications. This treatment, particularly in case of enucleation not preceded by marsupialization for volumetric reduction of the lesion, may cause irreversible damage to important anatomical structures and the collapse of the bone architecture. The purpose of this case report is to show the benefits of an endoscopic trans-nasal approach for the definitive treatment of such a clinical situation. The surgical technique aimed to remove part of the cystic wall and to open the inner compartment of the lesion to the nasal cavity after the resection of the anterior edge of the inferior turbinate and the lateral wall of the inferior nasal meatus. After a follow-up period of 18 months, without any problem or discomfort for the patient, the cyst appeared radiologically healed without the loss of any lesion-associated tooth. The bone nasal cavity, the maxillary sinus and the anterior alveolar process architecture, noticeably modified by the expansive enlargement of the cyst, resulted completely restored with a complete recover of the respiratory and oral functions

Conservative treatment of unicystic mural ameloblastoma

Mural ameloblastoma is a subtype of Unicystic Ameloblastoma characterised by the expansion or infiltration of tumour nodules into the fibrous wall of the cyst. The behaviour of this subtype is highly aggressive, with a risk of recurrence comparable with that of Conventional Ameloblastoma. Consequently, the preferred treatment for Unicystic mural Ameloblastom is broad resection of the tumour. In this case report we describe the successful conservative treatment of a Unicystic mural Ameloblastom associated with an impacted tooth. The conservative treatment consinsted in a initial marsupialization followed by the enucleation of the lesion performed with a lateral corticotomy to create a \u201cbone door\u201d and the relocation of the \u201cbone door\u201d using microplates and titanium screws. Our conservative approach preserved the integrity of the inferior alveolar nerve as well as mandibular functionality and resulted in a good aesthetic outcome. Due to the behaviour of this lesion, a strict follow up is mandatory. In our experience, follow-up is conducted as long as possible regardless of the surgical treatment. This protocol includes Cone Beam CT performed 1 year after surgery and panoramic radiology (OPG) once a year until 5 years after surgery. OPG is then repeated every 3 years in patients with Unicystic Ameloblastoma and every 2 years in those with Conventional Ameloblastoma or ameloblastoma with mural invasion. Suspected recurrence should be evaluated by CBCT

COVID-19 dentistry-related aspects: a literature overview

A new coronavirus (Sars-CoV-2) was detected in China at the end of 2019 and has since caused a worldwide pandemic. This virus is responsible for an acute respiratory syndrome (COVID-19), distinguished by a potentially lethal interstitial bilateral pneumonia. Because Sars-CoV-2 is highly infective through airborne contamination, the high infection risk in the dental environment is a serious problem for both professional practitioners and patients. This literature overview provides a description of the clinical aspects of COVID-19 and its transmission, while supplying valuable information regarding protection and prevention measures

A rare case of solitary fibrous tumor of the temporal region: 7-year-follow-up clinical-radiographic evaluation and literature review

Solitary fibrous tumor is a rare spindle-cell neoplasm of mesenchymal origin. In head and neck region, the tumors present slow-growing masses, often with local compressive symptoms. Although it is generally benign, malignant variants have been identified. The radiological diagnosis of solitary fibrous tumor is usually based on computer tomography and/or magnetic resonance imaging. Microscopically, a solitary fibrous tumor is characteristically a circumscribed neoplasm composed of variably cellular and patternless distributions of bland spindle and ovoid cells within variably collagenous stroma that frequently shows areas of dense hyalinisation, as well as interspersed large branching or “staghorn”- shaped thin-walled vessels. Immunohistochemical staining is very effective to distinguish solitary fibrous tumors from other fibroblastic tumors. Recently, NAB2–STAT6 gene fusion derived from inv12 (q13q13) has been reported as the genetic hallmark of solitary fibrous tumor. Complete local surgical excision appears to be the treatment of choice for solitary fibrous tumor of the head and neck region. Recurrence was reported in 5% of cases. The median recurrence-free interval was 36.5 months. We report the case of a solitary fibrous tumor of the temporal region, surgically excised and with no clinical and/or radiological signs of recurrence after 7 years of follow-up

Ulcerative oral lesions: an overview of non-pharmacologic treatment options

Background and Objective: Ulcerative diseases frequently affect the oral cavity and are disabling conditions. The management is challenging, and traditional treatments are associated with potential side effects. Alternative non-pharmacologic strategies have become available to effectively manage these conditions. This review aims at providing a synthesis of the most common erosive-ulcerative oral diseases and an updated overview of the main non-pharmacologic options for their management, such as laser therapy, ozone applications, and photodynamic therapy. Methods: A narrative review was conducted by searching PubMed/MEDLINE for the most recent relevant systematic reviews or, alternatively, clinical trials or case reports. Results: Laser photobiomodulation therapy (PBMT), ozone therapy and photodynamic therapy (PDT) generally resulted in rapid relief of painful symptoms, reduced healing time and improved oral functions and patients’ quality of life. No major side-effects were reported. Regardless of the primary etiology, photodynamic therapy proved particularly effective in case of infections. Ozone was used in gaseous, ozonized water and oil formulations. The most used light sources were Nd:YAG, He:Ne, Er,Cr:YSGG, red and infrared diode lasers and LED for PBMT, while red diode lasers prevailed for PDT. The most common photosensitizers were methylene blue and toluidine blue O. Conclusions: There is growing evidence for an efficacy of PBMT, ozone and PDT for the treatment of ulcerative oral lesions, and therefore these approaches should be considered as valid non-pharmacologic strategies. However, due to the great heterogeneity of protocols, additional well-designed research to identify the best therapeutic protocols is needed. (www.actabiomedica.it)

Analysis of Marsupialization of Mandibular Cysts in Improving the Healing of Related Bone Defects

Purpose: Marsupialization, designed to reduce the mandibular cyst volume, has continued to debated regarding its influence on the healing of the related bone cavity. The aim of the present study was to evaluate the 3-dimensional radiographic variation over time in mandibular odontogenic cystic lesions after marsupialization and assess the correlations between these variations and variables that can affect the procedure. Materials and Methods: We planned a retrospective cohort study. The predictor variables were the treatment duration, preoperative volume, patient age, histologic type, and number of preoperative residual bony walls. The outcomes variables were the postoperative volume reduction and the daily reduction rate calculated using computed tomography (CT) from before to after marsupialization using software designed for volumetric reconstruction and measurement of cyst-related bone defects. The descriptive and bivariate statistics were computerized, and the significance level was set at P =.05. Results: The sample included 15 patients (12 men and 3 women; mean age, 51.6; range, 27 to 85 years) affected by keratocysts (n = 6), dentigerous cysts (n = 6), and radicular cysts (n = 3) who had undergone marsupialization. The median duration of marsupialization was 406 days (25th to 75th percentile, 276 to 519). The mean ± standard deviation (SD) pre- and postdecompression volumes were 6,908.27 ± 2,669.058 and 2,468.13 ± 1,343.517 mm3, respectively (P < 0.001), and the mean ± SD percentage of reduction was 63.90 ± 13.12%. The volume decrease in the bone defects correlated positively with the treatment duration (P =.009) and preoperative volume (P <.001). However, no correlation was found with the other variables (P >.05) nor between the daily reduction rate and other variables (P >.05). Conclusions: Marsupialization appears useful in improving the healing of cyst-related bone defects in mandibles, especially larger defects. Further studies with a wider sample size would add more knowledge to this topic

Enucleation of a multilocular odontogenic keratocyst using sagittal osteotomy: A case report

Odontogenic keratocysts are significant cysts of the jaw that are characterized by aggressive behavior and a high tendency to recur. The treatments of choice may be radical or conservative, and in the literature a debate is still open about the gold standard in the treatment of OKCs.This report describes a wide multilocular OKC extended in the right mandibular ramus and illustrates atypical behavior of a cystic lobe after marsupialization, not found to our knowledge in the previous literature. Moreover, an orthognathic procedure, consisting of sagittal osteotomy was chosen for the excision of the cyst to preserve as much bone as possible and the integrity of the inferior alveolar nerve