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31.
When paranasal deficiencies are not accompanied by occlusal alterations, mobilization of the maxilla via Le Fort I osteotomy may not be justified. In this preliminary, report for the first time is presented a U-shaped osteotomy (USO) that mobilizes anteriorly and/or superiorly the maxillary bone surrounding the pirifom aperture. Advantages and indications of this new procedure are discussed.  相似文献   
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应用"摇椅形"弓丝矫治前牙开牙合的临床研究   总被引:5,自引:2,他引:5  
目的 研究“摇椅形”弓丝对前牙开牙合畸形的矫治效果。方法 对 14例前牙开牙合的患者应用“摇椅形”弓丝同时配合前牙区垂直牵引进行矫治 ,通过分析矫治前后X线头颅定位侧位片 ,评价其矫治效果。结果 矫治后上下颌切牙伸长、内收 ,下颌磨牙直立 ,牙合平面改建 ;同时控制了开牙合患者垂直方向的生长。结论 应用“摇椅形”弓丝同时配合前牙区垂直牵引矫治开牙合畸形符合利用固定矫治器治疗开牙合的机理 ,能获得良好的矫治效果。  相似文献   
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To find evidence of salivary gland involvement in human type I diabetes, we explored the changes in aminotransferase and lactate dehydrogenase activities, as indices of cellular injury, in the whole saliva of diabetic children. Although no significant difference in these enzymatic activities was observed between control and diabetic children as a whole, a negative correlation was found between enzymatic activities and duration of the disease, the highest values being detected in the diabetic subgroup diagnosed for less than 4 years. This suggests that some cell damage could be present in salivary glands of recently diagnosed diabetic children, likely as a result of immune-mediated alterations. In conclusion, these results may support the hypothesis that, as in rodents, the salivary glands could be an additional target of the immunological attack mainly directed against pancreatic beta-cells and resulting in type 1 diabetes.  相似文献   
35.
There are few studies on pediatric oral pathologies in the literature. This study presents data from a review of 2,356 biopsies of young patients (birth to 14 years) received over 15 years (1985-2000) in the Oral Pathology Service at the University of Sao Paulo, Brazil. Information about patients (sex, age, race) and histopathological diagnosis was retrieved. Diagnosis data of 2,356 biopsies were classified into 20 groups. There was no significant difference between male (50.0%) and female (49.0%) patients. White is the predominant race (69.0%), and patients ages were concentrated between 9 and 14 years old (70%). Mucocele was the most frequent (13.5%), followed by dentigerous cyst (6.5%) and fibrous hyperplasia (5.4%). Papilloma and Langerhans cells histiocytosis were the most common non-odontogenic benign and malignant tumors, respectively. In the group of odontogenic tumors, odontoma was the most frequent, and ameloblastoma had a significant incidence (27 cases). These data are important in order to detect differences in geographic areas, diagnosis line tendencies and for clinicians to perform judgment to evaluate of the pediatric patients before the biopsy and management of pediatric oral lesions.  相似文献   
36.
IL-1RN gene polymorphism is associated with peri-implantitis   总被引:1,自引:0,他引:1  
Objectives: Interleukin (IL)‐1α, IL‐1β and their natural specific inhibitor IL‐1 receptor antagonist (IL‐1ra) play a key role in the regulation of the inflammatory response in periodontal tissues. Polymorphisms in the IL‐1 gene cluster have been associated with severe adult periodontitis. We aimed to investigate the IL‐1 gene cluster polymorphisms in patients with peri‐implantitis. Material and methods: The study included 120 North Caucasian individuals. A total of 71 patients (mean age 68 years, 76% smokers) demonstrating peri‐implantitis at one or more implants as evidenced by bleeding and/or pus on probing and bone loss amounting to >3 threads on Brånemark implants and 49 controls (mean age 66 years, 45% smokers) with clinical healthy mucosa and no bone loss around the implants were recruited for the study. The titanium implants, ad modum Brånemark, had been in function for at least 2 years. Mouthwash samples were collected and used for genotyping of the bi‐allelic polymorphisms IL‐1A?889, IL‐1B+3953, IL‐1B?511 and a variable number of tandem repeat IL‐1RN gene polymorphisms using PCR technique. Results: Significant differences were found in the carriage rate of allele 2 in the IL‐1RN gene between peri‐implantitis patients and controls (56.5% vs. 33.3%, respectively; odds ratios (OR) 2.6; 95% confidence interval (CI) 1.2–5.6; P=0.015). Logistic regression analysis taking smoking, gender and age into account confirmed the association between the IL‐1RN allele 2 carriers and peri‐implantitis (OR 3; 95% CI 1.2–7.6; P=0.02). Conclusions: Our results provide evidence that IL‐1RN gene polymorphism is associated with peri‐implantitis and may represent a risk factor for this disease.  相似文献   
37.
The purpose of this study was to investigate, in vivo, the bond strength of two adhesive materials: a moisture insensitive primer (MIP)* and a one step self etching primer (SEP)*, both used with Transbond XT* on dry and wet enamel and an adhesion time of 10-15 minutes. First or second upper and/or lower bicuspids (n = 124), to be extracted for orthodontic reasons, were used. A comparison of the materials' behavior was conducted under four different situations: 1) MIP on enamel etched and dry; 2) MIP on a surface etched and wetted with patient's saliva; 3) SEP on a dry field, 4) SEP on a saliva-wet enamel. For statistical analysis, Dunn-Sidak's multiple comparison test was applied with a probability of less than 0.05 (before correction). Stainless steel brackets with mesh-backed pads were bonded to the teeth. Bond strength was tested with modified orthodontic pliers on which a strain-gage was fixed to measure handle deformation while debonding. Moisture insensitive primer tested on wet enamel showed the highest mean bond strength outcomes (8.98 MPa) compared to one step etching primer (5.81 MPa). Statistical difference between these groups was significant (p = 0.000). Standard deviation was lower for the one-step technique, under dry and wet conditions. Since the media bond strength of SEP proved sufficient for clinical purposes and its behavior tended to be more homogeneous, this was considered the best choice.  相似文献   
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颞下颌关节外科   总被引:4,自引:0,他引:4  
颞下颌关节 (temporomandibularjoint,TMJ)外科广义讲包括所有需要应用外科手段治疗的TMJ疾病以及关节周围疾病。解剖学、病理形态学、生物化学、免疫学、影像诊断学、生物力学以及医学工程学等方面的进步都为TMJ外科的发展奠定了基础 ,新知识、新理论和新手术方法改变了TMJ外科的面貌和方向。 2 0世纪 70年代以前主要涉及处理TMJ结构 ,解决关节强直 ,80年代以后逐步转向关节镜外科 ,90年代至今关节镜应用的范围在扩大 ,关节重建的方法已更新 ,人工关节的设计、制作和临床使用的报道也在增多。一、TMJ外科的内容1.TMJ损伤 :包括关…  相似文献   
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