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31.
OBJECTIVE: The purpose of this study was to demonstrate the sensitivity and specificity of multislice computerized tomography (CT) for diagnosis of maxillofacial fractures following specific protocols using an independent workstation. STUDY DESIGN: The study population consisted of 56 patients with maxillofacial fractures who were submitted to a multislice CT. The original data were transferred to an independent workstation using volumetric imaging software to generate axial images and simultaneous multiplanar (MPR) and 3-dimensional (3D-CT) volume rendering reconstructed images. The images were then processed and interpreted by 2 examiners using the following protocols independently of each other: axial, MPR/axial, 3D-CT images, and the association of axial/MPR/3D images. The clinical/surgical findings were considered the gold standard corroborating the diagnosis of the fractures and their anatomic localization. The statistical analysis was carried out using validity and chi-squared tests. RESULTS: The association of axial/MPR/3D images indicated a higher sensitivity (range 95.8%) and specificity (range 99%) than the other methods regarding the analysis of all regions. CONCLUSION: CT imaging demonstrated high specificity and sensitivity for maxillofacial fractures. The association of axial/MPR/3D-CT images added important information in relationship to other CT protocols.  相似文献   
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Trauma to deciduous anterior teeth, frequently occur in children, and the treatment is a big challenge for the pediatric dentistry. In these cases, besides the pain and discomfort provoked by the injury, both child and parents/persons responsible were eager to reconstruct the damage, as soon as possible. In modern operative restorative dentistry, no restorative material is able to substitute for the human dental enamel in quality, color and resistance. The aim of this paper is to relate the treatment of esthetic veneer (facet) of human dental enamel in a three-year-old child after trauma that caused concussion and accentuated color alteration. Clinical results showed an efficient esthetical resolution, revealing it to be a good alternative for treatment of traumatized anterior deciduous teeth.  相似文献   
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Optimal facial esthetics is one of the objectives in orthodontic treatment and an important issue in modern society. In this context, orthodontic treatment permits individuals with dental malpositions to achieve improved dentofacial esthetics. To reach this result, the orthodontist needs to recognize the characteristics considered normal and pleasant in dental arches and smiles. The objective of this article is to review and discuss criterion adopted by dental literature to technically analyze the smile, such as dental midline, smile line, dental exposure, negative space, dental proportion, and symmetry. This article proposes a way to visualize an ideal smile for each patient.  相似文献   
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This study quantified microleakage in restorations made with three packable resin composites-Solitaire, SureFil and P60; one hybrid resin composite-Z250 and an amalgam-Dispersalloy, with or without the thermocycling process. Sixty sound, freshly extracted human molars were sectioned mesiodistally, creating buccal and lingual blocks. One hundred blocks with the flattest surface were selected. Cylindrical cavities with a diameter of 1.85 +/- 0.05 mm and a depth of 1.5 mm were prepared with a special diamond bur. The blocks were randomly assigned to 10 test groups (n = 10): five restorative materials and two thermal stress groups (thermocycled groups at 3,000 cycles at 5 degrees C and 55 degrees C with a dwell time of one minute at each temperature, or non-thermocycled). After the thermocycling test, the samples were immersed in 2% methylene blue for 12 hours. The samples were ground and the powder prepared for analysis in an absorbance spectrophotometer. All the results were statistically analyzed by the Kruskal-Wallis test and the Mann Whitney test. For the non-thermocycled groups, the means (microg/ml) of microleakage were: Amalgam-4.279 (a); Solitaire-4.148 (ab); Z250-3.418 (abc); P60-3.184 (bc); SureFil-2.890 (c). For the thermocycled groups, the means were: Amalgam-7.572 (a); Solitaire-5.471 (a); Z250-4.330 (ab); P60-3.418 (bc) and SureFil-2.779 (c). Thermocycling analysis showed no significant differences between the thermocycled and non-thermocycled groups for each material tested. It was concluded that no test material prevented microleakage. Only SureFil and P60 showed leakage means significantly lower than amalgam, with SureFil showing lower leakage than Solitaire. P60 only showed lower leakage than Solitaire in the thermocycled groups and Z250 showed results similar to the others materials.  相似文献   
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To evaluate the retention and caries experience effects of three different materials used as fissure sealants after 24 months of clinical application: a resin-modified glass ionomer cement (A), a flowable resin composite (B) and a compomer (C). One hundred and seventeen (117) teeth were sealed with material A, 119 teeth with material B and 120 teeth with material C. Children were randomly assigned. Each one received only one of the materials studied. Plaque index, dmft score and socioeconomic level were scored at baseline. The clinical exams were conducted 6, 12 and 24 months after application of the sealant. Statistical analysis (Kruskal-Wallis) revealed that there were statistically significant differences between the retention rates of groups A and B and between groups B and C after 2 years, with material B showing better results. After 2 years, 3.1% of the teeth of group A, 4.3% of group B and 6.7% of group C were Carious+Filled. There was no evidence of association between caries presence after 2 years and plaque index, dmft score and socioeconomic level. These results suggest that flowable resin composite had a satisfactory retention after this period of evaluation and all three materials were effective on occlusal caries prevention.  相似文献   
37.
Age-related changes in human sublingual glands: a post mortem study   总被引:1,自引:0,他引:1  
OBJECTIVES: To analyse age- and gender-related microscopic changes in sublingual glands obtained from human cadavers. STUDY DESIGN: One hundred eighty six human sublingual glands were obtained from 93 autopsies. Approximately five individuals of each gender per decade of life were allocated to three age groups: group I (0-30 years, n=26); group II (31-60 years, n=32) and group III (61-90 years, n=35). The specimens were fixed in 10% formalin and submitted to routine histological processing, and sections were stained with hematoxylin and eosin. RESULTS: Significant differences with increasing age were observed for the following microscopic aspects: acinar atrophy (r=0.26, p=0.0115); replacement of parenchyma by fibrous tissue (r=0.79, p<0.0001) and/or adipose tissue (r=0.63, p<0.0001); oncocytosis (r=0.61, p<0.0001); duct-like structures (chi(2)=14.68, p=0.0006) and congested blood vessels (chi(2)=7.18, p=0.0276). The mononuclear infiltrate changed from focal to diffuse with age (H=8.47, p=0.0144). No significant differences were observed between genders. CONCLUSIONS: The aging process starts with acinar atrophy, followed by the presence of duct-like structures and ends with the replacement of the parenchyma by fibrous and/or adipose tissue. The mononuclear infiltrate changes from focal to diffuse. No difference in the aging of the sublingual glands is observed between men and women.  相似文献   
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