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The purpose of this study was to evaluate the clinical efficacy of platelet-rich plasma, autologous bone, and autologous fibrinogen as cryoprecipitate in maxillary sinus augmentation procedures. Six patients (age range, 29-58) undergoing sinus augmentation procedures were included in the study. Platelet-rich plasma and autologous fibrinogen in the form of cryoprecipitate were prepared from 300 ml of blood. Sinus augmentation was performed with intraoral bone grafts, platelet-rich plasma, and cryoprecipitate. The amount of regeneration was then evaluated quantitatively and qualitatively with Spiral TC (Dentascan) pre- and postoperatively 6 months after the intervention. Orthopantomography was performed preoperatively 3 and 6 months after the surgery. A mean platelet concentration of 320.5% was obtained from the baseline platelet blood count. The tomographic analysis indicated an average bone augmentation of 6.27 mm (range, 3.5-10 mm). Radiologically, a satisfactory morphological recovery of the maxillary jaw was obtained. No graft resorption was noticed. Orthopantomography indicated mineralization as early as 3 months postoperatively in the entire study population. This technique appeared to be safe and effective. Our preliminary results encourage the clinical use of platelet-rich plasma associated with cryoprecipitate.  相似文献   
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Acute phase protein levels as an index of severity of physical injury   总被引:1,自引:0,他引:1  
Inflammation resulting from any form of tissue injury causes an increase in plasma concentration of a number of liver-derived proteins (the acute phase reactant proteins), the measurement of which provides an indication of the magnitude of the inflammatory response. C reactive protein (CRP) is an example of an acute phase protein. Although concentrations increase particularly dramatically in response to inflammation and reflect the degree of ongoing tissue damage, this method has yet to be used to assess severity of injury in traumatology and forensic medicine. The rate at which the acute phase protein response occurred after injury was therefore explored in a series of 16 patients with maxillofacial skeletal injuries and in a series of 22 age- and sex-matched control patients. Increases in the plasma concentration of CRP were not detected until 6-12 h after injury and peaked at 48-72 h. Concentration of CRP was less than 10 mgm/l in all control patients. There was significant relation between peak levels and Abbreviated Injury Scale and Injury Severity scores. Results suggest that this method of assessing the severity of traumatic injury deserves further investigation and may be of use clinically, medico-legally and in relation to compensation awards.  相似文献   
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A quantitative study of the elastic fibres found in the human temporomandibular disc and its attachments was performed. Seven left discs from 57- to 82-year-old subjects, without macroscopic evidence of a TMJ disorder, were analysed and prepared in parasagittal sections. The surface amount was measured, thresholded and expressed from 0 to 1, using microscopic digitized views after Weigert's resorcin-fuchsin staining of elastic fibres. Fibre density rates ranged from 0 to 0.687. The mean density was 0.1532 (sigma=0.1150) in the upper bilaminary zone, 0.1097 (sigma=0.1159) in the lower bilaminary zone, 0.0474 (sigma=0.0782) in the anterior band, 0.0180 (sigma=0.0603) in the posterior band and null in the intermediate zone. The difference in density rate between the structures was significant, except for the posterior band and the intermediate zone. The elastic fibre density rates in central and medial locations of the upper and lower bilaminary zones were twice as big as in the lateral locations. In the anterior band, the elastic fibre density was less abundant medially than in its lateral part. These quantitative results support the current elastic fibre distribution scheme, and confirm the necessity of studying their orientation, taking into account age and temporomandibular joint health parameters.  相似文献   
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This study assessed the impact on happiness and quality of life of the cosmetic treatment of frontal teeth. This was compared with the impact of a restorative, not primarily cosmetic, treatment in the (pre)molar region on happiness and quality of life. The hypothesis that a cosmetic dental treatment makes a person happier or improves the quality of one's life was not supported by the results of the present study. In fact, oral health-related quality of life appeared to decline after the dental cosmetic treatment. Further research is needed to assess whether the results of the present study can be replicated in a larger sample and how the findings can be explained.  相似文献   
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PURPOSE: To evaluate fetuses with normal intracranial anatomy in the second trimester that became abnormal in the third trimester. METHODS: We sonographically examined 6 fetuses with a normal second-trimester head sonogram that presented later in pregnancy with an abnormal head sonogram. RESULTS: Four categories of intracranial pathology were depicted: obstructive hydrocephalus, intraventricular intracranial hemorrhage, non-intraventricular intracranial hemorrhage, and porencephaly. CONCLUSIONS: Despite a normal midtrimester intracranial examination, evaluation of the fetal intracranial contents should be undertaken in subsequent sonographic examinations, because significant pathology can develop spontaneously.  相似文献   
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Supraspinal processes in humans can have a top‐down enhancing effect on nociceptive processing in the brain and spinal cord. Studies have begun to suggest that such influences occur in conditions such as fibromyalgia (FM), but it is not clear whether this is unique to FM pain or common to other forms of chronic pain, such as that associated with osteoarthritis (OA). We assessed top‐down processes by measuring anticipation‐evoked potentials and their estimated sources, just prior (< 500 ms) to laser heat pain stimulation, in 16 patients with FM, 16 patients with OA and 15 healthy participants, by using whole‐brain statistical parametric mapping. Clinical pain and psychological coping factors (pain catastrophizing, anxiety, and depression) were well matched between the patient groups, such that these did not confound our comparisons between FM and OA patients. For the same level of heat pain, insula activity was significantly higher in FM patients than in the other two groups during anticipation, and correlated with the intensity and extent of reported clinical pain. However, the same anticipatory insula activity also correlated with OA pain, and with the number of tender points across the two patient groups, suggesting common central mechanisms of tenderness. Activation in the dorsolateral prefrontal cortex was reduced during anticipation in both patient groups, and was related to less effective psychological coping. Our findings suggest common neural correlates of pain and tenderness in FM and OA that are enhanced in FM but not unique to this condition.  相似文献   
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