Block of the mitral-pulmonary isthmus during ablation of a single left-sided accessory pathway causing different patterns of retrograde atrial activation

The case of a 16-year-old patient with atrioventricular tachycardia caused by a single left anterolateral accessory pathway is reported. When the patient underwent radiofrequency ablation, a lesion on the mitral annulus lateral wall produced changes in the retrograde atrial activation pattern determined by that pathway; changes ranged from a delay in depolarization of the annulus posterior portions to full left atrium counterclockwise activation. Such phenomena were probably caused by a block in the isthmus between the annulus and the lower left pulmonary vein ostium. This case illustrates the importance of the mitral-pulmonary isthmus in the process of left atrium activation, an alert to changes induced by its unintentional block during accessory pathway ablation.     

The effect of IL-1 receptor antagonist on orthodontic tooth movement in mice

ObjectiveOrthodontic tooth movement (OTM) is achieved by alveolar bone remodelling induced by mechanical loading. Whilst interleukin-1 (IL-1) is directly involved in OTM, the role of interleukin-1 receptor antagonist (IL-1Ra), a naturally occurring IL-1 antagonist, is not completely defined. Therefore, the aim of this study was to investigate the effects of IL-1Ra on OTM.MethodsAn orthodontic appliance was placed in C57BL6 mice treated with vehicle or IL-1Ra (10 mg/kg/day). OTM and TRAP-positive osteoclasts were evaluated after 12 days of mechanical loading and the levels of cytokines on periodontal tissues were analysed by ELISA after 12 and 72 h.ResultsMice treated with IL-1Ra showed diminished OTM and decreased numbers of TRAP-positive osteoclasts. In line with this, lower levels of IL-1β and TNF-α, and higher levels of IL-10, were observed on periodontal tissues of IL-1Ra-treated mice in relation to the vehicle-treated group.ConclusionThe present study suggests that IL-1Ra downregulates OTM, probably by its anti-inflammatory actions.     

Bleeding assessment in oral surgery: A cohort study comparing individuals on anticoagulant therapy and a non-anticoagulated group

Some prospective studies have been designed specifically to investigate perioperative bleeding in dental surgery. The quantitative assessment of intraoperative blood loss can be useful for indicating the real risk of bleeding complications, especially in medically compromised individuals. The aim of this study was to evaluate the pattern of bleeding in individuals under vitamin K antagonist (VKA) therapy and non-anticoagulated individuals submitted to dental extractions. Perioperative bleeding was evaluated by using a total collected bleeding corrected by absorbance reading (dental bleeding score). 138 procedures were performed. When the perioperative dental bleeding score was correlated with the number of extracted teeth, the quantity of bleeding was found to be directly proportional to the procedure. Extractions of two or more teeth presented higher scores than single extractions (p = 0.003). In a comparative analysis between the VKA and non-anticoagulated groups, no significant difference in the scores was found. The previous history of complications in dental procedures (p = 0.001) and the use of additional hemostatic measures were higher in the VKA group (p = 0.017). VKA therapy did not impact significantly the volume of blood lost during dental extractions. Perioperative bleeding assessment might be a useful parameter for evaluating patients under antithrombotic treatment.     

Cone-beam computed tomography analysis of cemento-osseous dysplasia-induced changes in adjacent structures in a Brazilian population

Clinical Oral Investigations - To describe the effects of cemento-osseous dysplasia (COD) on anatomical structures. CBCT scans were retrospectively selected from a database of individuals who...     

Evaluation of the reliability of computerized profile cephalometric analysis

The use of computers as an auxiliary instrument for case evaluation and procedures in health sciences is not new, and their advantages are well known. A growing number of orthodontists are using computerized systems for cephalometric analysis. Thus, this study evaluated the reliability of both computerized and manual methods used for creating profile cephalograms. Fifty profile radiographs were selected from the files of the Post-Graduate Course in Orthodontics at the Dental School of the Federal University of Rio de Janeiro. The good quality of the material was the only necessary requirement for selection. Results were submitted to the interclass correlation coefficient and a reliable similarity between cephalometric data obtained through both evaluated methods was found. However, the clinical utilization of computerized cephalometric analysis is not absolutely reliable.     

Pilomatricoma of the auricular region: case report

Pilomatricomas are relatively rare tumors of ectodermal origin from the outer root sheath cell of the hair follicle. They are usually asymptomatic, solitary, firm or hard, freely mobile, dermal or subcutaneous nodules. The purpose of this article is to present a case that illustrates the diagnostic difficulty encountered by oral surgeons and pathologists and to review the literature regarding pilomatricomas of the auricular region.