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991.
ObjectiveOptimal tooth reduction is a key requirement for aesthetics, function, and the longevity of fixed restorations. Research has demonstrated that controlled and conservative tooth preparation is crucial for the long-term success of adhesive restorations. Different techniques of fabricating reduction guides have been previously reported in literature. The present technical note describes the fabrication technique and clinical application of a customized metal preparation reduction guide.Material and methodPatient presented with tilted maxillary left central incisor. The flared-out part of the tooth was modified prior to veneer restoration preparation. Resin pattern reduction guide was fabricated on the diagnostic cast with a window on the tilted mesial portion of the tooth. After intraoral evaluation, resin pattern guide was casted. Metal reduction guide was place intraorally and reduction was provided on the exposed surface of the tooth. After the removal of the tilted portion, a harmonious arch form allowed the clinician to provide adequate evaluation and preparation for veneer restorations.ResultsThe device demonstrated good practical value, allowing for selective and controlled reduction of tooth structure, and definitive protection of adjacent tooth surfaces from iatrogenic damage. The clinical outcome successfully addressed the patient’s restorative and aesthetic needs, and the veneer was stable 2 years postoperatively.ConclusionUse of a metal guide assists clinicians to provide a more predictable reduction of a desired tooth surface, while decreasing the risk of compromising the other/adjacent tooth surfaces.  相似文献   
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This study aims to evaluate the epidemiological and molecular features associated with HAV transmission in adults in Rio de Janeiro during a period of increased registered cases of HAV (2017–2018). Socio-epidemiological data and serum samples from anti-HAV IgM+ individuals were obtained. HAV RNA was RT-PCR amplified and sequenced for further phylogenetic and phylogeographic analyses. From fifty-two HAV IgM+ individuals, most were men (78.85%; p = 0.024), aged 20–30 years old (84.61%; p < 0.001), resided in the Rio de Janeiro north zone (31/52; 59.62%; p = 0.001), and are men who have sex with men (MSM) (57.69%; p = 0.002). Sexual practices were more frequent (96%) than others risk factors (food-borne (44%), water-borne (42.31%), and parenteral (34.62%)). Individuals who traveled to endemic regions had a 7.19-fold (1.93–36.04; p < 0.01) increased risk of HAV. Phylogenetic analysis revealed four distinct clades of subgenotype IA, three of them comprised sequences from European/Asian MSM outbreaks and one from Brazilian endemic strains. Bayesian Inference showed that the imported strains were introduced to Brazil during large mass sportive events. Sexual orientation and sexual practices may play a role in acquiring HAV infection. Public policies targeting key populations must be implemented to prevent further dissemination of HAV and other STIs.  相似文献   
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Background: In recent years, modifications of treatment protocols introduced in pediatric oncology have resulted in a significant improvement in treatment outcomes. Unfortunately, the probability of subsequent malignant neoplasm (SMN) in this group of patients is 3 to 6 times higher than the general age-matched population. In this study, we sought to evaluate the treatment options for patients with secondary bone tumors after prior anti-cancer therapy. Materials and Methods: Twenty-four patients (median age 12.9 years) with subsequent malignant bone tumors were treated according to oncological guidelines for bone sarcoma during the period 1991–2020. All patients had a standard tumor imaging and laboratory evaluation. All toxicities were documented. Results: The median time from the first neoplasm to SMN was 7.6 years (range 2.4 to 16.3 years). All patients received chemotherapy and underwent surgery as a local control procedure. Two patients with Ewing sarcoma had additional radiation on the tumor bed. A complete response was achieved in 20 patients. With a median follow-up of 18.3 years (range 5.7 to 40.3 years), 18 patients (75%) are alive. The estimated 5-year post-subsequent bone malignant neoplasm survival was 74.5% (95% CI 55–95%). Fourteen patients required chemotherapy dose modification, and doxorubicin was discontinued in seven patients. One patient required a renal transplant two years after treatment. There were no other significant toxicities. Conclusions: The treatment of bone SMNs can be effective, although in many patients it is necessary to reduce the doses of drugs. Early detection and aggressive treatment can improve the outcome.  相似文献   
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Introduction

Tinea capitis (TC) is a dermatophytosis that affects the hair and scalp. The epidemiology of TC depends on the different geographical areas and is variable over time. Direct microscopic examination and fungal culture are essential to confirm the diagnostic suspicion and to identify the germ involved.

Objectives

To determine the frequency of TC, to identify the etiological agents and to analyze the epidemiological aspects, in patients with suspected TC from Santiago Norte during the period 2009-2015.

Materials and methods

A total of 505 patients with suspected TC were evaluated in the Dermatology Laboratory, Hospital Clinico Universidad de Chile. Direct microscopic examination was performed with KOH 30% and fungal culture of scalp lesions. Identification of the fungi was mainly morpho-physiological.

Results

The diagnosis of TC was confirmed in 155 cases (30.7%). Male gender predominated (57.4%). The average age was 5 years. 85.2% of the cases occurred in the preschool and school population. The most frequent isolated agent was Microsporum canis in 89.8%, followed by Trichophyton tonsurans in 7.1%. It was confirmed that 81.8% of the cases of Trichophyton tonsurans had foreign ancestry, mainly of Haiti and Peru.

Conclusions

This study evidenced the occurrence of Trichophyton tonsurans as a cause of TC, which could be explained by the increase in the immigrant population and the anthropophilic characteristics of the dermatophyte.  相似文献   
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