RESUMO
Ameloblastic fibroma (AF) is a rare, slow-growing benign neoplasm, comprised of tissues of odontogenic origin. It constitutes 2% of odontogenic tumours, occurring at any age, but has a predilection to present in the first two decades of life. AF principally affects the posterior mandible. It is characterized by epithelial islands and cords immersed in ectomesenchyme that mimics the dental papilla and enamel organ but without actual hard tissue formation. Herein, we describe the case of a 6-year-old Caucasian male who presented to the Oral and Maxillofacial Department at Alder Hey Children's Hospital, Liverpool, UK, with a painless expansile mass in the left mandible which was diagnosed as a benign ameloblastic fibroma and subsequently enucleated and reconstructed with a parietal calvarial bone graft. A brief literature review and the issues surrounding diagnosis are discussed.
RESUMO
Regional odontodysplasia (RO) also known as ghost teeth is a rare developmental anomaly affecting the mesodermal and ectodermal components of teeth with characteristic clinical and radiographic findings. The enamel and dentin are hypomineralized and hypocalcified with short roots and open apices. The affected teeth have an abnormal morphology, meaning they are fragile and thin and liable to fracture and decay. Radiographically, there is a marked reduction in radiodensity with little distinction between the enamel and dentin, hence the term "ghost teeth." RO generally affects one particular segment in one or both arches of the maxilla or mandible and can affect both the primary and permanent dentition. We report a unique case of a 3-year-old female who presented to Alder Hey Children's Hospital acutely unwell with a left-sided cervicofacial swelling from RO affecting the entire portion of the left maxilla.
RESUMO
Organometal mixed-halide perovskite materials hold great promise for next-generation solar cells, light-emitting diodes, lasers, and photodetectors. Except for the rapid progress in the efficiency of perovskite-based devices, the stability issue over prolonged light illumination has severely hindered their practical application. The deterioration mechanism of organometal halide perovskite materials under light illumination has seldom been conducted to date, which is indispensable to the understanding and optimization of photon-harvesting process inside perovskite-based optoelectronic devices. Here, explicit degradation pathways and comprehensive microscopic understandings of white-light-induced degradation have been put forward for two organometal mixed-halide perovskite materials (e.g., MAPbI3-xClx and MAPbBr3-xClx) under high vacuum conditions. In situ compositional analysis and real-time film characterizations reveal that the decomposition of both mixed-halide perovskites starts at the grain boundaries, leading to the formation of hydrocarbons and ammonia gas with the residuals of PbI2(Cl), Pb, or PbClxBr2-x in the films. The degradation has been correlated to the localized trap states that induce strong coupling between photoexcited carriers and the crystal lattice.
RESUMO
INTRODUCTION: Tumours of the parapharyngeal space are rare. Only 0.5% of head and neck tumours occur in this space. Surgical excision of parapharyngeal space lesions is challenging because of the anatomical complexity of the area. PRESENTATION OF CASE: A 31-year-old male patient was referred by his general dental practitioner for removal of lower wisdom teeth due to multiple episodes of pericoronitis. At the initial examination, an incidental finding was made of a large fluctuant posterior oropharyngeal swelling. A fluid aspirate was taken from the lesion but this was inconclusive. The patient underwent an urgent MRI and CT neck revealing a large parapharyngeal mass. An incisional biopsy of the lesion confirmed the presence of a vagal nerve schwannoma which was subsequently removed via a transcervical approach. DISCUSSION: Due to their slow growing and painless nature, they are often not detected until they are large enough to palpate or visualise. It may cause secondary symptoms such as dysphagia, hoarseness and nasal obstruction. This case represents a typical presentation of a parapharyngeal schwannoma and reiterates the subtle and often ambiguous nature of the lesion. CONCLUSION: Vagal schwannomas in the parapharyngeal space are rare. They usually present in the form of an isolated intraoral or neck mass. A positive diagnosis is made on imaging and confirmed by histopathological examination. Complete surgical excision is the treatment of choice and recurrence rates are low.
RESUMO
This paper examines the distinct world of online poker. It outlines the online poker eco-system, and the players which inhabit it, their distinctive attitudes and behaviors towards the game and gambling. These unique patterns of behavior have been created and sustained by the interaction of players within online poker forums. Therefore online poker forums were identified as primary mechanism within which a poker sub-culture may exist. The study conducted an extensive netnography of online poker forums. The study found that within the online poker eco-system there are forums which are elevated to sacred status amongst this online poker sub-culture. The members of these forums enact sub-cultural characteristics such as ethos of collaboration/cooperation, and a competitive hierarchy of status. In particular this paper identifies the importance of identity generation, and communities within the online poker eco-system.
