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71.
Objectives

The aim of this study was to analyze the amount of root resorption of maxillary lateral incisors by relating the position, location, and angulation of the impacted canine using cone-beam computed tomography (CBCT).

Materials and methods

The study sample consisted of panoramic and CBCT radiographs of 46 patients with a unilateral impacted canine (16 males and 30 females; mean age: 19.53 ± 6.66 and 19.44 ± 5.77 years, respectively). Sector location and canine angulation were measured in panoramics. All tomographs were obtained using CBCT (NewTom 5G, QR, Verona, Italy) and three-dimensional (3D) reconstructions of the maxillary laterals assessed by Mimics 14.01 image analysis software.

Results

Upper lateral incisor volume was smaller on the impacted side (401.95 ± 83.69 mm3) than on the nonimpacted side (433.54 ± 92.6 mm3, P < 0.05). There were no significant differences of lateral root resorption volume when comparing the impacted canines being on the labial or palatal sides (P > 0.05), but impacted canine angulation was significantly steeper on the labial side (70.85°) than on the palatal side (46.09°, P < 0.05). The volume of root resorption of laterals when comparing the various positions of the canine in different sectors or canine angulation in 30o intervals was not statistically significantly different (P > 0.05).

Conclusions

The impacted canines caused root resorption of lateral incisors. The angulation of the canine was steeper on the labial side than on the palatal side but root resorption of adjacent laterals was not different. There were no statistically significant differences in the amount of root resorption of the laterals when the canine was evaluated according to localization and angulation.

  相似文献   
72.
73.
Background: Although many factors seem to have an impact on the resonance frequency (RF) values of implants, there is a lack of evidence about some other parameters, which may have an influence on implant stability. Purpose: The aims of the study were to determine whether initial stability of a dental implant differs when the buccolingual width of the bone changes, to determine whether different orientations affect the RF measurements in the RF device, and to investigate two dental implants with different morphologies with regard to their initial stability. Materials and Methods: Two implant systems (Tidal Spiral Dental Implant Systems, Huntsville, AL, USA, and MIS Seven, MIS Implants Technologies Ltd., Shlomi, Israel) with diameters of 3.75 mm and 4.2 mm and with a length of 13 mm were used. Following the insertion of implants, buccolingual thinning of the models was performed in 2‐mm increments ranging between 0 and 8 mm. Results: A statistically significant decrease for implant stability quotient (ISQ) values was noticed for both diameters and both systems for all dimensional time points of the blocks (p < .05). The second system (more number of threads) resulted with higher ISQ values for both diameters than the first system (lower number of threads) (p < .001). The orientation of the probe influenced the measurements, where a standard orientation is advisable for the magnetic RF device. Conclusion: Different implant surface geometries seem to behave in different patterns in terms of initial stability. Dimensional changes in buccolingual direction seem to have an impact on the initial stability, where wider implants also presented higher ISQ values than narrow ones.  相似文献   
74.
75.
OBJECTIVE: Anti-RNA polymerase I/III (anti-RNAP I/III) antibodies are clinically useful markers of scleroderma, and their presence is associated with diffuse skin disease and an increased risk of cardiac and kidney involvement. Although RNAP I antibodies localize to the nucleolus, nucleolar staining by many anti-RNAP antibody-positive sera is not always observed. Nucleolar staining by anti-RNAP antibody-positive sera was examined by double staining with antifibrillarin antibodies to evaluate whether nucleolar staining can be used as a screening test for anti-RNAP I/III antibodies. In addition, the relationships between nucleolar staining and levels of anti-RNAP III antibodies were examined by enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation (IP) assay. METHODS: Sera were tested using immunofluorescent antinuclear antibodies on HEp-2 cell slides, by anti-RNAP III ELISA, and by IP assay using (35)S-labeled K562 cell extract. Nucleolar staining by anti-RNAP antibody IP-positive sera was confirmed by double staining using antifibrillarin monoclonal antibodies. The levels of anti-RNAP III antibodies were quantitated by ELISA and by IP assay using a serially diluted reference serum as a standard, and their relationship was analyzed. RESULTS: All 18 anti-RNAP I/III antibody-positive sera showed nuclear speckled patterns, but nucleolar staining was readily noticeable in only 44% of the sera. A positive correlation was found between ELISA and IP units for anti-RNAP III antibodies. The levels of anti-RNAP III antibodies and anti-RNAP I antibodies correlated well, with the exception of a few sera. Levels of anti-RNAP III antibodies were low in sera with nucleolar staining, whereas several sera with high levels of anti-RNAP I antibodies clearly showed nucleolar staining. CONCLUSION: Although some sera positive for anti-RNAP I/III antibodies clearly stain nucleoli, nucleolar staining is inconsistent and cannot be used to screen for anti-RNAP I/III antibodies.  相似文献   
76.
Colonic complications of Behcet''s disease due to intestinal involvement are rarely reported in the literature. Ulcers are the most frequently seen intestinal complications that cause bleeding and perforation predominantly in the ileocecal region. In this article, we report a patient with Behcet''s disease who presented with multiple perforations along the entire colon. Postoperative histopathological examination revealed multiple ulcers containing lymphocytic infiltrations in the small peripheral and submucosal venules. Intimal thickening and fresh intraluminal fibrin thrombosis were also seen in these venules.  相似文献   
77.
A false aneurysm of the left ventricle that is in fact a contained rupture is rare. False aneurysms have been reported to be mostly at the posterior-basal and rarely at the apical segments of the left ventricle. Early surgical intervention is recommended because of the risk of rupture. This report describes the successful surgical management of two patients with false aneurysms of the left ventricle, located at the lateral wall and the inferior wall following a recent inferior and lateral-wall myocardial infarction.  相似文献   
78.
BACKGROUND: Varied vascular and biliary anatomies are common in the liver. Living donor hepatectomy requires precise recognition of the hilar anatomy. This study was undertaken to study donor vascular and biliary tract variations, surgical approaches and implications in living liver transplant patients. METHODS: Two hundred living donor liver transplantations were performed at our institution between 2004 and 2009. All donors were evaluated by volumetric computerized tomography (CT), CT angiography and magn...  相似文献   
79.
Certain viral and bacterial infections may contribute to the initiation and progression of atherosclerosis. The aim of this study is to determine whether Helicobacter pylori (HP) seropositivity contributes to conventional atherosclerosis risk factors in the development of an early sign of atherosclerosis: intima-media thickness (IMT) of the carotid artery. Eighty-four patients who had at least two conventional atherosclerosis risk factors and a control group of 50 patients having no risk factors for atherosclerosis were enrolled in the study. None of the patients had ever received HP eradication treatment. HP IgG antibodies were determined by enzyme-linked immunosorbent assay. Carotid artery IMT was measured 1 cm before the carotid bifurcation. Seventy-five percent of the study group was HP seropositive. HP seropositive (n=64) and seronegative (n=21) groups were identical in terms of sex distribution, smoking pattern, mean age, hemoglobin, leukocyte, platelet, C-reactive protein, erythrocyte sedimentation rate, glucose, cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein, systolic blood pressure and diastolic blood pressure levels. There was no significant difference between the mean carotid IMT of HP seropositive (0.8+/-0.3 mm) and negative (0.8+/-0.3 mm) patients in the study group. Similar to the study group, there was no statistically significant difference between mean carotid IMT of HP seropositive (0.56+/-0.19 mm) and negative patients (0.67+/-0.13 mm) in the control group (p=0.2). Future studies concerning virulent strains are needed to determine the probable role of HP in atherosclerosis.  相似文献   
80.
Colon hemangiomas are rare benign vascular lesions which are usually seen in teenagers. The frequent presentation is repetitive painless rectal bleeding. Colonic hemangiomas are occasionally found in the rectosigmoid area. A 62-year-old male patient was admitted to the hospital with the complaints of mechanical bowel obstruction. The radiological imaging techniques revealed a transverse colon tumor. Consequently, the patient was operated, and transverse colectomy and end-to-end anastomosis were performed. No postoperative complications occurred. The pathologic examination revealed cavernous hemangioma of the transverse colon. This report describes a very rare case of bowel obstruction due to colonic hemangioma.  相似文献   
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