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991.
An emergency thoracotomy (ET) is a surgical procedure rarely practiced outside a hospital. However, it can be the only way to resuscitate a patient who has suffered cardiac arrest due to penetrating chest trauma. SAMUR-Protección Civil is a two-tier Emergency Medical Service of Madrid, with Advance Life Support teams led by Emergency Physicians, Emergency Nurses and Paramedics. Over the last 3 years, medical teams from SAMUR have performed ET in six cases, after a short period of cardiac arrest, restoring cardiac output in two cases, and one patient with a normal neurological outcome. The following SAMUR protocol describes these emergency situations and details the case of the patient who was treated and discharged from hospital without any repercussions.  相似文献   
992.
The aim of this study was to validate a Task-Specific Self-Efficacy Scale for Chinese people with mental illness. The study included 79 men and 77 women with chronic mental illness. The Task-Specific Self-Efficacy Scale for People with Mental Illness (TSSES-PMI) and Change Assessment Questionnaire for People with Severe and Persistent Mental Illness were used as measures for the study. Factor analysis of the TSSES-PMI resulted in four subscales: Symptom Management Skills, Work-Related Skills, Help-Seeking Skills, and Self-Emotional-Regulation Skills. These community living skills were found to be related to the level of readiness for psychiatric rehabilitation among Chinese people with mental illness. In conclusion the results support the construct validity of the TSSES-PMI for the Chinese population and the TSSES-PMI can be a useful instrument for working with Chinese people with mental illnesses.  相似文献   
993.
Unicystic ameloblastoma (UA) is a benign epithelial odontogenic tumor of the jaws with an aggressive potential that commonly occurs in children. This cystic odontogenic neoplasm is generally asymptomatic and found during routine radiographs. The purposes of this report were to describe a case of UA involving the crown of the unerupted right mandibular second premolar in an 11-year-old girl under orthodontic treatment, and discuss its diagnosis and radiographic and microscopic findings, emphasizing its distinction from the dentigerous cyst and the inflammatory follicular cyst.  相似文献   
994.
The purpose of this case report was to describe the management of a mandibular dentigerous cyst in a 10-year-old male patient. Without any clinical symptom, the lesion was detected in a routine panoramic radiograph showing a well-defined osteolytic lesion that measured 3 cm in diameter, partially surrounding the crown of the canine, first molar, and second premolar displacing the teeth to the mandible's lower border. The apex of the teeth were still open. Under local anesthesia, the patient was treated by: extraction of the left deciduous canine and first and second deciduous molars; and marsupialization of the cystic cavity. After 30 months, the premolar had erupted and an orthodontic therapy was started to maintain space for the canine.  相似文献   
995.
996.
This study was undertaken to explore the effect of heating on gutta-percha, analyzing the occurrence of endothermic peaks corresponding to the transformation that occurs in the crystalline structure of the polymer during thermal manipulation. This study also sought to determine the temperature at which these peaks occur, causing a transformation from the beta- to the alpha-form, and from the alpha- to the amorphous phase. Eight nonstandardized gutta-percha points commercially available in Brazil (Konne, Tanari, Endopoint, Odous, Dentsply 0.04, Dentsply 0.06, Dentsply TP, Dentsply FM) and pure gutta-percha (control) were analysed using differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The transition temperatures were determined and analysed. With the exception of Dentsply 0.04 and Dentsply 0.06, the majority of the products showed thermal behaviour typical of beta-gutta-percha, with two endothermic peaks, exhibiting two crystalline transformations upon heating from ambient temperature to 130 degrees. Upon cooling and reheating, few samples presented two endothermic peaks. It was concluded that heating dental gutta-percha to 130 degrees C causes changes to its chemical structure which permanently alter its physical properties.  相似文献   
997.
Tonsillolith is a rare dystrophic calcification as a result of chronic inflammation of the tonsils. Three asymptomatic cases of tonsillolith are reported, incidentally discovered through panoramic radiographs, which showed different sizes of radiopaque images, varying from 2 to 5 mm; cases I and III images did not overlap the mandible ramus, which led to a probable diagnosis of soft tissue calcification. Case II had radiopaque unilateral images, with osseous tissue density, overlapping the mandibular ramus, leading to a benign intra-osseous lesion, which was considered as differential diagnosis. No symptoms were reported in any case. Only case I had clinical characteristics, showing highly consistent white plaques partially visible through the mucosa. Computed tomography of the maxillofacial region/head and neck were requested to find out the exact location of these images, since most of the overlapping radiopaque images in the mandibular ramus were very similar to intra-osseous abnormalities. The computed tomography showed hyperdense images in the palatine tonsils, confirming the diagnosis of tonsillolith. The patients are currently under follow-up. No treatment is required if there is no symptom. In conclusion, tonsillolith might show images on panoramic radiographs similar to intra osseous abnormalities. The diagnosis is relatively easy when computed tomography is requested, although the images are not pathognomonic. Therefore, clinicians should consider other pathologies as differential diagnosis.  相似文献   
998.
PURPOSE: To test the effects of sequential application of potassium oxalate gel/adhesive agent on in vitro dentin permeability. MATERIALS AND METHODS: Full crown preparations were made in extracted human molars to expose deep coronal dentin. The roots and pulp were removed and the resulting crown segments were connected to a special device (Flodec) to permit the measurement of the permeability of the specimens before and after treatments. Minimum and maximum permeability were recorded after smear layer and phosphoric acid treatment. A new smear layer was created and the permeability measured after the crowns were bonded with Single Bond (3M ESPE), One-Up Bond F (Tokuyama), and AdheSE (Ivoclar Vivadent), either according to manufacturer's instructions or after treating the acid-etched dentin with a 3 wt% potassium oxalate gel. The results were expressed as a percentage of maximum permeability values. Impressions and epoxy resin replicas from the crown segments were produced for SEM examination. RESULTS: None of the adhesives were able to eliminate the fluid flow through dentin. Two-way ANOVA revealed that the application of potassium oxalate prior to the bonding procedures was the most effective technique in reducingthe dentin permeability (p < 0.05), regardless of the adhesive used. SEM micrographs showed that transudation of dentinal fluid could be identified on the surfaces of all replicas. CONCLUSION: The use of potassium oxalate gel was effective in reducing the permeability of bonded dentin.  相似文献   
999.
Idiopathic osteosclerosis (IO) is described as a localized no expansible radiopacity with unknown etiology. The IO is generally asymptomatic and could appear as round, elliptical or irregular in shape. The internal aspect is usually uniformly radiopaque. IO should be distinguished from condensing osteitis of dental origin, or other alveolar bone related radiopacities such as periapical cemental dysplasia. This condition may cause changes in tooth position or problems during orthodontic treatment. The purpose of the present study is to report a case of tooth resorption caused by ectopic eruption rote caused by IO. This condition represents a rare complication of IO.  相似文献   
1000.
The purpose of this study was to develop a technique to evaluate the implant-abutment gap of an external hexagon implant system as a function of radius. Six implants of 3.75 mm in diameter (Conexao Sistema de Protese Ltda, Sao Paulo, Brazil) and their respective abutments were screw connected and torqued to 20 N cm(-1). The implants were mounted in epoxy assuring an implant long-axis position perpendicular to the vertical axis. Each implant was grounded through its thickness parallel to implant long-axis at six different distance interval. Implant-abutment gap distances were recorded along the implant-abutment region for each section. Individual measurements were related to their radial position through trigonometric inferences. A sixth degree polynomial line fit approach determined radial adaptation patterns for each implant. Micrographs along implant sections showed a approximately 300 mum length implant-abutment engagement region. All implants presented communication between external and internal regions through connection gaps and inaccurate implant-abutment alignment. Average gap distances were not significantly different between implants (P > 0.086). Polynomial lines showed implant-abutment gap values below 10 mum from 0 mum to approximately 250 mum of the implant-abutment engagement region. Gap distances significantly increased from approximately 250 mum to the outer radius of the implant-abutment engagement region. The technique described provided a broader scenario of the implant-abutment gap adaptation compared with previous work concerning implant-abutment gap determination, and should be considered for better understanding mechanical aspects or biological effects of implant-abutment adaptation on peri-implant tissues.  相似文献   
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