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101.
The aim of this study was to analyze a possible correlation of different cephalometric measurements to define facial type and to evaluate the best measurement for diagnosis. The sample consisted of 95 lateral cephalograms of caucasian patients with normal occlusion, aged between 15 years and two months and 21 years and four months, of which 54 were male and 41 female. The facial types were divided into dolichofacial, mesofacial and brachyfacial, according to the standards stated by different authors, and a relationship among them was investigated using the Kappa and Total agreement methods. The highest agreement found was between FMA and SN.GoGn; the lowest was between SN. Gn and VERT index. According to literature review and the interpretation of the results, SN.GoGn appears to be the best measurement to define facial type.  相似文献   
102.
Abstract – Objectives: To compare the fracture resistance of bovine teeth after intracoronal bleaching with sodium percarbonate (SPC) or sodium perborate (SP) mixed with water or 20% hydrogen peroxide (HP). Materials and methods: Fifty extracted bovine teeth were divided into four experimental groups (G1–G4) and one control (n = 10) after endodontic treatment. Following root canal obturation, a glass ionomer barrier was placed at the cemento–enamel junction. After that, the pulp chambers were filled with: G1 – SP with water; G2 – SP with 20% HP; G3 – SPC with water; and G4 – SPC with 20% HP. No bleaching agent was used in the control group. Coronal access cavities were sealed with glass ionomer and specimens were immersed in artificial saliva. The bleaching agents were replaced after 7 days, and teeth were kept in artificial saliva for an additional 7 days, after which the pastes were removed and the coronal access cavities were restored with glass ionomer. Crowns were subjected to compressive load at a cross head speed of 0.5 mm min?1 applied at 135° to the long axis of the root by an EMIC DL2000 testing machine, until coronal fracture. Data were statistically analysed by anova and Tukey test. Results: No differences in fracture resistance were observed between the experimental groups (P > 0.05). However, all experimental groups presented lower fracture resistance than the control group (P < 0.05). Conclusion: SPC and SP led to equal reduction on fracture resistance of dental crowns, regardless of being mixed with water or 20% HP.  相似文献   
103.

Objective

The aim of this cross-sectional study was to evaluate the relationship among pain intensity and duration, presence of tinnitus and quality of life in patients with chronic temporomandibular disorders (TMD).

Material and Methods

Fifty-nine female patients presenting with chronic TMD were selected from those seeking for treatment at the Bauru School of Dentistry Orofacial Pain Center. Patients were submitted to the Research Diagnostic Criteria anamnesis and physical examination. Visual analog scale was used to evaluate the pain intensity while pain duration was assessed by interview. Oral Health Impact Profile inventory modified for patients with orofacial pain was used to evaluate the patients'' quality of life. The presence of tinnitus was assessed by self report. The patients were divided into: with or without self report of tinnitus. The data were analyzed statistically using the Student''s t-test and Pearson''s Chi-square test, with a level of significance of 5%.

Results

The mean age for the sample was 35.25 years, without statistically significant difference between groups. Thirty-two patients (54.24%) reported the presence of tinnitus. The mean pain intensity by visual analog scale was 77.10 and 73.74 for the groups with and without tinnitus, respectively. The mean pain duration was 76.12 months and 65.11 months for the groups with and without tinnitus, respectively. The mean OHIP score was 11.72 and 11.74 for the groups with and without tinnitus, respectively. There was no statistically significant difference between groups for pain intensity, pain duration and OHIP scoreS (p>0.05).

Conclusion

Chronic TMD pain seems to play a more significant role in patient''s quality of life than the presence of tinnitus.  相似文献   
104.

Background

The dentigerous cyst is usually defined as a cystic cavity that surrounds the crown of an unerupted tooth on the cementoenamel junction. The present article reports a case of an uncommon dentigerous cyst, highlighting its clinical, radiographic and surgical characteristics and discussing the aspects related to its development in infancy.

Case report

A 03-year-old boy patient presented with an extensive radiolucid area involving the crown of the right maxillary lateral incisor. A surgical excision was performed. Anatomopathological examination revealed a cystic tissue with a fibrous wall surrounded by nonkeratinized stratified squamous oral epithelium, without atypia.

Conclusion

It is possible that the dentigerous cyst grows in the dental germ in any stage of development and not only in the follicle of a tooth with calcified crown attached to the cementoenamel junction.  相似文献   
105.

Purpose

Malignant gliomas are associated with alteration in EGF/EGFR signaling. Functional EGF+61A>G polymorphism is implicated with risk, recurrence, and progression of glioma. This study aimed to establish a putative association of EGF+61A>G with risk of glioma development, production of angiogenic growth factor EGF, and the response to perillyl alcohol administered by intranasal route.

Methods

The study included 83 patients with recurrent glioma enrolled in Phase I/II trial for intranasal perillyl alcohol therapy and subjects without cancer (n?=?196) as control group. DNA was extracted from blood samples, EGF genotype performed with PCR–RFLP assay, and EGF circulating levels by enzyme immunoassay. Adequate statistical tests were performed to verify associations between polymorphism and glioma risk, and genotype correlation with EGF circulating levels. The log-rank test was also used to evaluate differences on patient survival.

Results

Patients with primary glioblastoma had high frequency of AA genotype (p?=?0.037) and A allele (p?=?0.037). Increased EGF circulating levels were observed in glioma patients with AA (p?=?0.042), AG (p?=?0.006), and AA?+?AG (p?=?0.008) genotypes compared with GG. Patients with GG genotype showed increased but not significant (p?>?0.05) survival rate, and EGF levels lower than 250?pg/mL was consistently (p?=?0.0374) associated with increased survival.

Conclusion

Presence of EGF+61A>G polymorphism in Brazilian subjects was associated with glioma risk and increased circulating EGF levels. Better response to perillyl alcohol-based therapy was observed in a group of adult Brazilian subjects with lower EGF levels.  相似文献   
106.
目的:对比分析5种暂时冠桥材料的抗压强度。方法:参照标准制作直径4 mm,高6 mm的圆柱形试件50个,甲基丙烯酸酯即自凝树脂(A组)、Integrity(B组)、Luxatemp(C组)、Temphase(D组)、Protem 3 Garan(tE组)5种暂时冠桥材料试件各10个,采用万能材料试验机测定其抗压强度,并进行统计分析。结果:A组抗压强度(210.28±20.07)MPa,显著低于其余4组(P<0.05),E组抗压强度最高(304.55±24.50)MPa,B、C、D组间无统计学差异(P>0.05),B、D、E组间也无显著性差异(P>0.05),C组和E组间抗压强度差异有统计学意义(P<0.05)。结论:5种暂时冠桥材料抗压强度间存在较大差异,Bis-acryl类材料较甲基丙烯酸酯类材料抗压强度高。  相似文献   
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