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101.
Maló P Nobre Mde A Petersson U Wigren S 《Clinical implant dentistry and related research》2006,8(4):223-232
Background: The current investigation focuses on new implant designs for increased predictability in clinically demanding situations. Microtextured implant surfaces create favorable conditions for enhanced osseointegration of dental implants compared to implants with a smooth surface, and the macroscopic implant design may influence implant stability. Purpose: The aim of the present study was to retrospectively evaluate the clinical performance of a novel implant design in the rehabilitation of completely edentulous jaws and in combination with an immediate function protocol. Materials and Methods: Forty‐six consecutive patients received 189 study implants (NobelSpeedyTM concept implant, Nobel Biocare AB, Göteborg, Sweden) supporting 53 full‐arch all‐acrylic prostheses (44 maxilla, 9 mandible). The majority (66%) of the reconstructions were supported by four implants, of which the two posterior implants were tilted. All patients were followed for a minimum of 1 year. Radiographic assessment of the marginal bone level was performed. Results: Two implants were lost in two patients, rendering a 1‐year cumulative clinical survival rate of 98.9%. The marginal bone level was, on average, situated 1.2 ± 0.7 mm below the implant‐abutment interface after 1 year of loading. Good soft tissue health and overall esthetic outcome was reported. Conclusions: The results of the present pilot study indicate that fully edentulous jaws with various types of bone can be treated with high success and good esthetics using immediately loaded implants with the presented design, and that favorable marginal bone levels can be maintained. 相似文献
102.
Cosentino TB Brazão-Silva MT Souza KC de Faria PR de Moraes S Loyola AM da Silva SJ Cardoso SV 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2008,106(2):e26-e29
Myoepithelial carcinoma is a rare and aggressive neoplasm of the salivary glands. One-third of the patients may develop regional distant metastases, and lungs and kidneys have been regarded as the most usual sites for implantation. There is, however, little information on the metastatic behavior of this malignancy. We report the first case of patient with multiple cutaneous metastases from a myoepithelial carcinoma of the submandibular gland, which depicted a very aggressive clinical course. 相似文献
103.
Gomes-Filho JE de Moraes Costa MM Cintra LT Duarte PC Takamiya AS Lodi CS Bernabé PF 《Journal of endodontics》2011,37(2):250-254
Introduction
The aim of this study was to evaluate the rat alveolar bone response after the implantation of experimental light-cured mineral trioxide aggregate (MTA) or Angelus MTA (Angelus, Londrina, Paraná, Brazil) by histological and fluorescence analysis.Methods
Thirty Wistar Albino rats were divided into three groups. In the control group, empty polyethylene tubes were inserted into the rat alveolar sockets immediately after extraction. In the other groups, the tubes were filled with light-cured MTA or Angelus MTA. Five animals from each group were injected with calcein on day 7, alizarin on day 14, and oxytetracycline on day 21. On day 30, these animals were killed, and the right hemimaxillas were removed and histologically processed. Half of the maxillas were processed and stained with hematoxylin and eosin. The remaining maxillas were processed for fluorescence analysis and stained with Stevenel blue and alizarin red. New bone was histomorphometrically evaluated using a Merz grid.Results
The light-cured MTA presented a similar response when compared with Angelus MTA; it was characterized by a mild inflammatory response and complete bone healing. In the light-cured MTA group, the fluorescence areas were more evident at 21 days, showing an increase in bone formation. However, dystrophic mineralization was observed only with Angelus MTA.Conclusions
It was concluded that both materials present a similar inflammatory response and bone healing, but dystrophic mineralization was observed only with Angelus MTA. 相似文献104.
Freitas-Junior AC Bonfante EA Martins LM Silva NR Marotta L Coelho PG 《The International journal of prosthodontics》2011,24(6):557-561
The reliability and failure modes of molar crowns supported by three different implant-supported designs were tested according to the following groups: group 1, one standard-diameter implant (3.75 mm); group 2, one narrow-diameter implant (3 mm); and group 3, two narrow-diameter implants (3 mm). Loads were applied as mouth-motion cycles using a step-stress accelerated life-testing method. ? values for groups 1 and 3 (1.57 and 2.48, respectively) indicated that fatigue accelerated the failure of both groups, but not for group 2 (0.39). Abutment screw failure was the chief failure mode. Strength and reliability were significantly higher for groups 1 and 3 compared to group 2. 相似文献
105.
Louly F Nouer PR Janson G Pinzan A 《Journal of applied oral science : revista FOB》2011,19(2):169-174
Objective
This study evaluated dental arch dimensional changes of Brazilian children.Material and methods
Dental casts were taken from 66 children (29 males; 37 females) with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dimensions were taken by one examiner using the Korkhaus’ compass and a digital pachymeter. ANOVA test was applied to compare the arch dimensions at the different ages and the t-test was used to compare the arch dimensions of male and female subjects. Arch forms were compared by means of chi-square tests.Results
Only the maxillary anterior segment length showed a statistically significant increase from 10 to 12 years of age. Males had a significantly larger maxillary depth than females at the age range evaluated. The predominant dental arch form found was elliptical.Conclusion
In the studied age range, anterior maxillary length increased from 10 to 12 years of age, males had larger maxillary depth than females and the predominant arch form was elliptical. 相似文献106.
OBJECTIVE: The aim of the study is to evaluate the measurement properties of the Brazilian version of the short form of the Oral Health Impact Profile (OHIP14). METHODS: Data were obtained from a cross-sectional study designed to assess the impact of toothache on quality of life during pregnancy. The sample consisted of 504 postpartum women (mean age 24 years; SD 6.2), most of whom had unsolved dental problems and belonged to low-income families. The questionnaire was administered in the form of interviews by two trained interviewers who also performed clinical examinations. Reliability was assessed in terms of internal consistency and stability. Construct validity was evaluated based on comparison of the total scores among groups according to: self-perceived and normative oral health care needs, self-perceived general and oral health status, presence of carious lesions and tooth loss. It was also hypothesized that the scores of OHIP14 and Oral Impacts on Daily Performances (OIDP) would correlate with each other. RESULTS: Both test-retest stability and internal consistency, as measured by the intra-class correlation coefficient (0.87) and by Cronbach's alpha (0.91), proved to be adequate. Construct validity was confirmed as the correlation between OHIP14 scores with self-perceived general and oral health were in the expected direction, and the differences in scores of the groups formed according to the selected attributes were significant at values of P < or = 0.05 (Mann-Whitney test). Moreover, the correlation coefficient between OIDP and OHIP14 was 0.76 (rs). CONCLUSION: The Brazilian version of OHIP14 has good psychometric properties, which are similar to those of the original instrument. 相似文献
107.
Novaes AB Souza SL de Oliveira PT Souza AM 《The International journal of oral & maxillofacial implants》2002,17(3):377-383
PURPOSE: The different implant systems available today present several types of surface treatment, with the aim of optimization of bone-implant contact. This study compared 4 different types of implant surfaces. MATERIALS AND METHODS: The first, second, third, and fourth mandibular premolars were extracted from 5 young adult mongrel male dogs. Ninety days after removal, four 3.75-mm-diameter, 10-mm-long screw-type implants (Paragon) were placed with different surface treatments in mandibular hemiarches. The dogs received 2 implants of each of the following surface treatments: smooth (machined), titanium plasma spray (TPS), hydroxyapatite coating (HA), and sandblasting with soluble particles (SBM). The implants were maintained unloaded for 90 days. After this period, the animals were sacrificed, and the hemimandibles were extracted and histologically processed to obtain non-decalcified sections. Two longitudinal ground sections were made for each implant and analyzed under light microscopy coupled to a computerized system for histomorphometry. RESULTS: The following means were obtained for bone-implant contact percentage: machined = 41.7%, TPS = 48.9%, HA = 57.9%, and SBM = 68.5%. DISCUSSION: The means for all treatments that added roughness to the implant surface were numerically superior to the mean found for the machined surface. However, this difference was statistically significant only between groups SBM and machined (Tukey test, P < .05). CONCLUSIONS: The SBM-treated surface provided a greater bone-implant contact than a machined surface after 90 days without loading in this model. 相似文献
108.
109.
Croider Franco LACERDA Paulo Anderson BERTULUCCI Ant?nio Talvane Torres de OLIVEIRA 《Brazilian archives of digestive surgery》2014,27(3):191-195
Background
Despite the increasing number of laparoscopic hepatectomy, there is little published experience.Aim
To evaluate the results of a series of hepatectomy completely done with laparoscopic approach.Methods
This is a retrospective study of 61 laparoscopic liver resections. Were studied conversion to open technique; mean age; gender, mortality; complications; type of hepatectomy; surgical techniques applied; and simultaneous operations.Results
The conversion to open technique was necessary in one case (1.6%). The mean age was 54.7 years (17-84), 34 were men. Three patients (4.9%) had complications. One died postoperatively (mortality 1.6%) and no deaths occurred intraoperatively. The most frequent type was right hepatectomy (37.7%), followed by bisegmentectomy (segments II-III and VI-VII). Were not used hemi-Pringle maneuvers or assisted technic. Six patients (8.1%) underwent simultaneous procedures (hepatectomy and colectomy).Conclusion
Laparoscopic hepatectomy is feasible procedure and can be considered the gold standard for various conditions requiring liver resections for both benign to malignant diseases. 相似文献110.
Fabricio Ferreira COELHO Marcos Vinícius PERINI Jaime Arthur Pirola KRUGER Gilton Marques FONSECA Raphael Leonardo Cunha de ARAúJO Fábio Ferrari MAKDISSI Renato Micelli LUPINACCI Paulo HERMAN 《Brazilian archives of digestive surgery》2014,27(2):138-144