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81.
The CICERO system for CAD/CAM fabrication of full-ceramic crowns   总被引:17,自引:0,他引:17  
The CICERO method of crown fabrication consists of optically digitizing a gypsum die, designing the crown layer buildup, and subsequently pressing, sintering, and milling consecutive layers of a shaded high-strength alumina-based core material, a layer of dentin porcelain, and a final layer of incisal porcelain. Final finishing is performed in the dental laboratory. The CICERO method allows efficient production of all-ceramic restorations without compromising esthetics or function. This article reviews the process involved in the fabrication of a CICERO crown.  相似文献   
82.
A case of unusual hamartoma in a six-year-old otherwise healthy Brazilian girl is reported, with emphasis on histological and immunohistochemical features. A mass observed in the incisive papilla was detected whose appearance was similar to congenital epulis or fibroma. Histological findings showed interlacing fascicles of large spindle cells resembling smooth muscle cells. Immunohistochemical staining for desmin and for smooth-muscle actin was positive. The histological diagnosis was leiomyomatous hamartoma, based on clinical and microscopic observations.  相似文献   
83.
The practice of dentistry is most often perceived as the treatment of the hard tissues of the oral region, specifically the teeth and jaws. However, there are many disorders and conditions involving surgical treatment of the soft tissues that extend to the adjacent and associated structures of the oral and maxillofacial surgery region.  相似文献   
84.
CT diagnosis of synovial chondromatosis of the temporomandibular joint   总被引:3,自引:0,他引:3  
Synovial chondromatosis of the temporomandibular joint (TMJ) is a very rare condition. It is characterised by the presence of loose bodies in the joint space. Clinical signs, histopathological findings and radiography play an important role in the diagnostic process. Conventional X-rays have shown to be of limited value, for they fail to depict the intra-articular loose bodies in a significant amount of cases. Axial as well as coronal computer tomography (CT) is extremely useful in detecting loose bodies in the temporomandibular joint (TMJ). In this report we present and discuss a further case, and the use of CT in the diagnosis of TMJ-synovial chondromatosis is illustrated.  相似文献   
85.
We are made 730 inquirys about mothers to study the age in the teething begin to relationship with personal details. The issue shows a light relation in the advance teething with tall, weight, beginning the walking and female sex, and we have not shown relation with the nursing.  相似文献   
86.
Assessment of denture satisfaction   总被引:2,自引:0,他引:2  
The aim of this investigation was to evaluate the reliability and validity of a complaints questionnaire, designed to measure different aspects of denture satisfaction. Two groups of patients with full maxillary and mandibular dentures participated in the study. The patients in Group 1 (n = 113) were on a waiting list for new dentures, patients in Group 2 (n = 102) had recently had new dentures fitted. Five denture complaint scales were constructed from the questionnaire. The internal consistency (coefficient alpha) of the scales varied from 0.65 to 0.92. Furthermore, the scales showed a discriminatory ability between the patient groups (P less than or equal to 0.001) and significant Pearson correlation coefficients with satisfaction-related questions (r = 0.25-0.79). The scores on the scales can be considered a quantitative measure of denture satisfaction.  相似文献   
87.
PURPOSE: The purpose of this study was to evaluate the amount of dentifrice applied to the toothbrush by school children using a liquid dentifrice (drop technique), when compared to toothpaste. MATERIALS AND METHODS: A total of 178 school children (4-8 years old) from two cities in Brazil (Bauru and Bariri) participated in the present two-part crossover study. Children from Bauru received training regarding tooth-brushing techniques and use of dentifrice before data collection. In each phase, the amount of toothpaste or liquid dentifrice applied by the children to the toothbrush was measured, using a portable analytical balance (+ 0.01 g). Data were tested by analysis of covariance (Ancova) and linear regression (p < 0.05). RESULTS: The mean (+/- standard deviation) amounts of toothpaste and liquid dentifrice applied to the toothbrushes for children from Bauru were 0.41 +/- 0.20 g and 0.15 +/- 0.06 g, respectively. For children from Bariri, the amounts applied were and 0.48 +/- 0.24 g and 0.14 +/- 0.05 g, respectively. The amount of toothpaste applied was significantly larger than the amount of liquid dentifrice for both cities. Children from Bariri applied a significantly larger amount of toothpaste, when compared to those from Bauru. However, for the liquid dentifrice, there was no statistically significant difference between the cities. A significant correlation between the amount of toothpaste applied and the age of the children was verified, but the same was not found for the liquid dentifrice. CONCLUSION: The use of the drop technique reduced and standardised the amount of dentifrice applied to the toothbrush, which could reduce the risk of dental fluorosis for young children.  相似文献   
88.
This study aimed to measure the active mandibular range of motion (ROM) (mouth opening: MO; right and left lateral movements: RL and LL; protrusion: P) in Brazilian children of both genders and of various ages, weights, and heights, and to establish correlations among such variables. Study subjects (n = 303) were healthy boys and girls, with ages ranging between 6 and 14 years, who were regular students of a public school in the state of S?o Paulo. Analysis of variance and intra-class correlation coefficients were considered significant for p < 0.05. Weak significant correlations were observed between mandibular ROM and age, height, and weight. No statistically significant differences (p > 0.05) were observed regarding mandibular ROM between gender groups. Mean mandibular ROM values showed significant increases (p < 0.05) in relation to age, height, and weight, except for RL (p > 0.05), in the studied age range. Significantly smaller (p < 0.05) mean mandibular ROM values were observed for the intervals of 6 and 7 years of age, 1.15-1.35 m, and 17.30-26.50 kg, in relation to the other ranges. Nonetheless, no differences were observed among mean mandibular ROM values in the ranges 8 to 12-14 years, 1.36-1.75 m, and 47-85 kg. Thus, it is suggested that weight, height, and age variables be considered when obtaining mandibular ROM values, particularly in children aged 6 to 7 years, measuring 1.15-1.35 m, and weighing between 17.3-46.5 kg.  相似文献   
89.
OBJECTIVES: To evaluate the bonding interface in experimentally weakened roots reinforced with adhesive restorative materials and quartz fibre posts, varying the light-exposure time of the composite resin used for root reinforcement. METHODS: Twelve extracted human maxillary incisors teeth were used. The crowns were removed and the roots were endodontically treated. After post space preparation, the roots were assigned to four groups. The thickness of the root dentine was reduced and adhesively restored with composite resin light-activated through a translucent fibre post for either 40s (group 1), 80s (group 2) or 120s (group 3). In the case of control (group 4), the roots were not weakened. One day after post cementation, the specimens were sectioned transversally in three slices and processed for scanning electron microscopic analysis to observe bonding interface formation, quality of the hybrid layer and density of resin tags using a four-step scale method. RESULTS: Formation of a hybrid layer and resin tags were evident in all groups. There was no statistically (p>0.05) significant difference between the regions analysed in each group (Friedman test) and between groups in each section depth (Kruskal-Wallis test). Furthermore, comparison of the flared/reinforced groups showed that the different times used for composite resin cure did not affect the results significantly (Kruskal-Wallis test, p=0.2139). CONCLUSIONS: Different light-exposure times used for composite resin polymerisation during root canal reinforcement did not affect significantly the formation and quality of the dentine/adhesive/composite resin bonding interface.  相似文献   
90.
The aim of this study was to verify the relationship between the inclination of the coronoid process of the mandible, and electromyographic activity of the anterior part of the temporal muscle in skeletal Class I and II individuals. Forty-seven volunteers (mean age 24.5 +/- 3.9 years) were subdivided into two groups, according to angle ANB: Class I (n = 25) and II (n = 22). Two radiographic examinations were performed; one lateral cephalogram to measure angle ANB, and one frontal cephalogram to measure the inclination of the coronoid process. Electromyographic (EMG) examination of the anterior part of the subjects' temporal muscles was performed. Statistical analysis of the data showed that Class II individuals presented lower electromyographic activity of the anterior part of the temporal muscle. Based on the results obtained, it was concluded that the skeletal classes analyzed had no influence on the inclination of the coronoid process. The inclination of the coronoid process was not influenced by the electromyographic activity of the anterior part of the temporal muscle in Class I and II individuals; however, the lower electromyographic activity of the anterior part of the temporal muscle could be influenced by the skeletal class in Class II individuals.  相似文献   
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