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Background: The Tubu are nomadic people who live in remote parts of the central Sahara, primarily in the Tibesti massif(Chad), and in both Northeastern Niger and Southern Libya. All of these areas are close to become conflict zones. However, no data about the Tubu’s health and sanitary status are currently available, which would be of major concern if humanitarian interventions would become required.Methods: In 1970, the "Mission Anthropologique Belge au Niger"(MABN) investigated a Tubu tribe named Broaya that lived at Seguedine and Djado on the northeastern rim of the Tenere desert. One hundred fifty-one adult volunteers answered an oral questionnaire and underwent a medical examination, followed by the collection of blood thin films and samples of urine and stool. The environmental fauna of medical importance was also studied.Results: Albeit 43 year-old, these results have not been previously published. The estimated age of death for fathers was approximately 56 years, and that for mothers was 60 years. On average, each married woman had had 4.7 children. The overall perinatal mortality rate was 232 ‰, the overall infant mortality rate was 153 ‰, and the overall child mortality rate was 99 ‰. The mean height was 164.1 cm and 157.4 cm, the mean weight was 50.1 kg and 47.9kg, and the mean blood pressure was 131/78 mm Hg and 127/75 mm Hg for males and females, respectively. The physical examination found 6 cases of blindness(4.0%). Five subjects presented with an elevated blood pressure(3.3%), and 5(3.3%) displayed an abnormal thoracic auscultation evocative of tuberculosis or of an acute lung infection. The abdominal examination and renal palpation found 5 large masses(3.3%), and 2 subjects had a palpable enlarged spleen(1.3%). The blood thin films were fixed in methanol and subsequently examined in Toulouse. The search for blood parasites was negative. The urine samples were centrifuged and then microscopically examined in the field. No blood-fluke eggs were found. The stool samples were mixed with a pre  相似文献   
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OBJECTIVE: The aim of this clinical study was to seek an answer to the question of whether CT gives better qualitative and quantitative information as compared to panoramic radiograph when deciding on extraction of upper impacted third molars. STUDY: The study concerned 34 third molars appearing in direct relation with the sinus on the panoramic radiograph for which a CT scan had been recommended. For each case, the panoramic radiograph was compared with the CT scan for 5 evaluation criteria. RESULTS: The CT scan was more precise than the panoramic radiograph by 1.67 mm for measurement of the level of impaction of the third molar, by 12.44 degrees for measurement of the third molar displacement, by 0.74 mm for bone height separating the third molar roots and the sinus, and by 2.26 mm for the length of roots in the sinus. The CT scan was equally accurate for measurement of the distance separating the crowns of second and third molars in 34 cases. CONCLUSIONS: This study confirms the gain in precision for the CT scan as compared with conventional techniques. The CT scan therefore presents advantages when considering the extraction of upper third molars by providing both qualitative and quantitative information liable to bear on the diagnosis and therapeutic management.  相似文献   
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PURPOSE: The purpose of this prospective multicenter study was to evaluate the efficacy of 3i threaded implants for the treatment of edentulous patients in a 1- to 5-year period. This article reports the total data and global results of 3 threaded designs of 3i implants: self-tapping, ICE, and Osseotite. MATERIALS AND METHODS: A total of 1,583 implants (619 ICE, 545 Osseotite, and 419 self-tapping) were placed between 1995 and 1999 in 528 patients at 13 European clinical centers. The average age of the patients was 53.6 years. Clinical and radiographic evaluations were performed annually for up to 5 years. RESULTS: Of the total implants, 707 were placed in the maxilla and 876 in the mandible. A total of 1,162 implants were placed in posterior segments. Forty-eight implants were lost to follow-up and 55 were failures. The most frequent prosthetic indication was the short-span fixed prosthesis (440 cases), followed by 172 single-tooth replacements, 56 long-span prostheses, and 4 overdentures. Radiographic evaluation after 6, 12, and 24 months of implant loading showed, respectively, mean crestal bone loss of 0.04 +/- 1.3 mm, 0.12 +/- 1.6 mm, and 0.2 +/- 1.7 mm. A cumulative survival rate of 96.5% was observed 5 years after implant placement, with 97.2% survival in the maxilla and 95.8% in the mandible. The survival rate was similar in anterior (96.7%) and posterior (96.5%) segments. DISCUSSION: A total of 55 failures were reported in this study with 47 early failures and 8 late failures. The rate of late failures is of utmost importance for the restorative dentist. CONCLUSION: This clinical study gives evidence of very high success rates using 3 threaded designs of 3i implants.  相似文献   
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Particulate parietal bone is used for maxillary sinus floor elevation procedure prior to dental implant placement. However, data on internal structure of the parietal bone and on graft remodeling and incorporation in the host bone are limited. We determined the structure and remodeling activities of 24 parietal bone specimens sampled at time of sinus grafting (T1 samples), and the amount and turnover of bone formed at the recipient site at time of implant placement (T2 samples, obtained 10 months after T1 samples, on average). In T1 samples, the outer cortex was 1.16+/-0.45 mm thick, had a typical haversian structure, and showed a low level of remodeling. In the cancellous portion of the samples, trabecular bone volume represented 52.8+/-10.3%. Bone remodeling was more active in the cancellous portion than in the cortical portion, but few osteoblasts and osteoclasts were seen. T2 samples consisted solely of trabecular bone, which occupied 49.4+/-18.4% of total sample volume. The boundary between new bone and the recipient bed was not discernible. Remnants of the graft particles were embedded within new bone, and showed signs of intense resorption. Bone remodeling was highly active, as shown by the presence of numerous osteoclasts resorbing new bone, together with thick osteoid seams and large osteoblasts. A loose cotton-like mineralized material was frequently observed in the marrow spaces; this acellular and non-collagenous material was strongly stained by toluidine blue, suggesting a glycoprotein nature. This study offers insights into cortical and trabecular bone structure and shows the low-level remodeling activity of parietal bone. About 10 months after grafting, the grafted chips were incorporated in new bone and almost completely resorbed. This high turnover may be beneficial for implant placement.  相似文献   
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