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991.
BACKGROUND: The present study evaluated the efficacy of controlled-release delivery of chlorhexidine gluconate (CHX) on clinical parameters and on gingival crevicular fluid (GCF) matrix metalloproteinase (MMP)-8 levels in chronic periodontitis patients. METHODS: Twenty patients with chronic periodontitis were screened for 6 months. Two interproximal sites were selected from mesial surfaces of anterior teeth with probing depths of 6 to 8 mm that bled on probing in each patient. There were at least 2 teeth between the selected sites. CHX chip was inserted into a randomly selected site following scaling and root planing (SRP+CHX), while the other selected site received only SRP in each patient. Probing depth (PD), clinical attachment level (CAL), plaque index (PI), and papilla bleeding index (PBI) were recorded at baseline and at 1, 3, and 6 months. GCF MMP-8 levels were analyzed at baseline; 2 and 10 days; and at 1, 3, and 6 months by immunofluorometric assay (IFMA). RESULTS: At baseline, there were no statistically significant differences in the mean PD, CAL, PBI, and PI scores between SRP+CHX and SRP alone groups. At 1, 3, and 6 months, all clinical parameters in each group significantly decreased (P <0.0167) when compared to baseline. The reduction of PD and improvement in CAL were higher in the SRP+CHX group compared to SRP alone at 3 and 6 months. However, the differences between the 2 groups were not statistically significant. PBI and PI scores were not significantly different between SRP+CHX and SRP alone groups at any visit. GCF MMP-8 levels were similar in both groups at baseline. Intragroup analysis showed significant decreases in the GCF MMP-8 level for the SRP+CHX group between baseline and 1, 3, and 6 months (P<0.01). Intergroup analysis demonstrated significantly lower mean levels of GCF MMP-8 at 1 month in the SRP+CHX group compared to the SRP alone group (P <0.05). CONCLUSIONS: These data suggest that CHX chip application following SRP is beneficial in improving periodontal parameters and reducing GCF MMP-8 levels for 6 months' duration. The use of a chairside MMP-8 dipstick periodontitis test might be a useful adjunctive diagnostic tool when monitoring the course of CHX chip treatment.  相似文献   
992.
BACKGROUND: The plasminogen activator (PA) system plays many roles in the inflammatory process and tissue remodelling and repair and is considered to play a significant role in periodontal tissue destruction and healing. The aim of this study was to evaluate the role of the PA system in cyclosporin A (CsA)-induced gingival overgrowth in renal transplant patients. METHODS: Eighteen renal transplant patients exhibiting moderate to severe CsA-induced gingival overgrowth, 10 other renal transplant patients receiving CsA therapy but showing no sign of CsA-induced gingival overgrowth (CsA-H), 16 chronic gingivitis patients (CG) and 16 systemically and periodontally healthy control subjects (H) were included in the study. Gingival crevicular fluid (GCF) samples were obtained from four randomly selected sites in each subject with the exception of the CsA-induced gingival overgrowth group, where four GCF samples were harvested from sites with severe overgrowth (CsA GO+) and from four sites without any gingival overgrowth (CsA GO-). The GCF levels of albumin, tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA), plasminogen activator inhibitor 1 (PAI-1) and plasminogen activator inhibitor 2 (PAI-2) were analysed by enzyme-linked immunosorbent assay. The results were tested for statistical differences. RESULTS: In CsA GO+ sites t-PA levels were significantly elevated in comparison with gingivitis and healthy sites, while PAI-2 levels in these sites showed statistically significant differences only with CsA-H and gingivitis sites (p<0.05). The levels of t-PA and PAI-2 were significantly higher in CsA GO- sites compared with those of CsA-H, gingivitis and healthy sites (p<0.05). The levels of u-PA and PAI-1 failed to show significant differences between the study groups. CONCLUSIONS: The findings of the present study indicate alterations in GCF t-PA and PAI-2 levels in CsA-induced gingival overgrowth and might suggest involvement of the plasminogen activating system in the pathogenesis of this side-effect of CsA therapy. However, to what extent these molecules contribute to the pathogenesis of CsA-induced gingival overgrowth remains to be determined.  相似文献   
993.
STATEMENT OF PROBLEM: Abutment and prosthetic loosening of single and multiple screw-retained, implant-supported fixed partial dentures is a concern. PURPOSE: The purpose of this study was to investigate stress distribution of preloaded dental implant screws in 3 implant-to-abutment joint systems under simulated occlusal forces. MATERIAL AND METHODS: Three abutment-to-implant joint systems were simulated by using the 3-dimensional finite element analysis method: (1) Branemark external hexagonal screw-retained abutment, (2) ITI 8-degree Morse tapered cemented abutment, and (3) ITI 8-degree Morse tapered plus internal octagonal screw-retained abutment. A thermal load and contact analysis method were used to simulate the preload resulting from the manufacturers' recommended torques in implant screw joint assemblies. The simulated preloaded implants were then loaded with 3 simulated static occlusal loads (10 N; horizontal, 35 N; vertical, 70 N; oblique) on the crown position onto the implant complex. RESULTS: Numeric and graphical results demonstrated that the stresses increased in both the abutment and prosthetic screws in the finite element models after simulated horizontal loading. However, when vertical and oblique static loads were applied, stresses decreased in the external hexagonal and internal octagonal plus 8-degree Morse tapered abutment and prosthetic screws with the exception of the prosthetic screw of ITI abutment after 70-N oblique loading. Stresses increased in the ITI 8-degree Morse tapered cemented abutment after both vertical and oblique loads. CONCLUSION: Although an increase or decrease was demonstrated for the maximum calculated stress values in preloaded screws after occlusal loads, these maximum stress values were well below the yield stress of both abutment and prosthetic screws of 2 implant systems tested. The results imply that the 3 implant-to-abutment joint systems tested may not fail under the simulated occlusal forces.  相似文献   
994.
BACKGROUND: The aim of the present study was to evaluate the effects of systemic administration of low-dose doxycycline and a bisphosphonate, alendronate, on serum levels of interleukin-1beta (IL-1beta), osteocalcin (OC), and C-reactive protein (CRP) in experimental periodontitis in rats. METHODS: Experimental periodontitis was induced by repeated injection of purified lipopolysaccharide (LPS) derived from Escherichia coli endotoxin. Forty-seven adult male Sprague-Dawley rats were divided into five study groups and given LPS, LPS + doxycycline, LPS + alendronate, LPS + doxycycline + alendronate, and saline control. At the end of the 1-week protocol, blood samples were obtained, and the rats were sacrificed. Serum samples were analyzed for IL-1beta, OC, and CRP concentrations by enzyme-linked immunosorbent assay (ELISA). The jaws were defleshed, and alveolar bone loss was assessed morphometrically. Data were evaluated statistically by non-parametric tests. RESULTS: Morphometric measurements revealed significantly more bone loss in the LPS group compared to the saline control group (P <0.05). Alendronate revealed slight inhibition on alveolar bone loss either alone or in combination with doxycycline (alveolar bone loss: 0.41 mm in alendronate and combined drug treatment groups versus 0.45 mm in LPS and doxycycline groups). Significantly higher IL-1beta levels were observed with alendronate either alone or in combination with doxycycline than in the LPS group (P <0.05). Combined administration of doxycycline and alendronate showed significantly higher levels of OC than all of the other groups (P <0.01). Serum CRP levels did not exhibit significant differences between the study groups. CONCLUSIONS: Alendronate either alone or in combination with doxycycline provided slight inhibition on LPS-induced alveolar bone resorption. The significantly increased serum OC level observed in the combined drug treatment group suggests that combined administration of alendronate and doxycycline might increase bone remodeling and thereby inhibit the progression of alveolar bone resorption in rats.  相似文献   
995.
Treatment options of maxillary fibrous dysplasia are surgical recontouring or total or partial maxillectomy depending on the site and behavior of the lesion. Among the reconstruction procedures, which include many surgical options, reconstruction using a maxillary obturator is the least invasive one. This report describes a case of aggressive maxillary fibrous dysplasia that was treated with a total maxillectomy and reconstructed with a malar implant-retained maxillary obturator.  相似文献   
996.
997.
The term “ES” has been widely used for describing a clinical condition consisting of skin rash, fever, and weight gain that occur during neutrophil recovery period following HSCT. In this study, the incidence, clinical features, risk factors, and outcomes of ES were evaluated in 169 children following allogeneic HSCT from full‐matched related donor according to the Spitzer criteria. Seventeen patients (10.1%) presented with clinical conditions suggesting ES. In both univariate and multivariate analysis underlying malignant disease and early release of monocytes to the PB, and in univariate analysis using only CsA for GVHD prophylaxis were found to be the significant risk factors for the development of ES. Patients with ES experienced significantly higher incidence of acute and chronic GVHD and propensity toward a higher rate of TRM. OS did not differ between the patient groups. Thirteen of 17 patients received steroid therapy, and all but one patient responded to therapy. Monitoring for early detection of ES and early intervention with steroid therapy is the key for recovery. The most crucial approach for this purpose mainly is to find out and use the most useful and feasible diagnostic criteria for routine medical practice.  相似文献   
998.
Aim Treatment modalities of vesicoureteral reflux (VUR) consist of antimicrobial prophylaxis and antireflux surgery. In this study, we aimed to determine if antireflux surgery changes the course of renal functional deterioration in children with VUR and urinary tract infections (UTI). Methods Medical files of patients with VUR diagnosed during evaluation for UTI were evaluated retrospectively for gender, age, follow-up period, and renal ultrasonography (US) and serial 99mTc-dimercaptosuccinic acid (99mTc-DMSA) scintigraphy findings. Estimated glomerular filtration rate and urinary protein levels were determined at the initial and last visits, and before the operation in children who had antireflux surgery. The patients were divided into two groups as solely medically treated (Group 1) and both medically and surgically treated (Group 2). Group 2 was further divided as those with stable renal function (Group 2a) and with progressive renal injury (Group 2b). Results There were 140 patients (77 female; mean age 51.6?±?51.9 months). Group 1 and Group 2 included 82 and 58 patients, respectively. In Group 2, the number of patients with the abnormal US, DMSA scintigraphy, and renal function was higher than in Group 1. Recurrent UTI rate was similar, but progressive scarring was more prominent in the antireflux surgery group. In Group 2, 31 patients had a stable renal function (Group 2a) while 27 had progressive deterioration of renal functions (Group 2b). These subgroups were not different with respect to the rate of high-grade VUR, the presence of a renal scar in DMSA, and UTI recurrence. However, the bilateral renal scar was more common in Group 2b. Conclusion Antireflux surgery does not change the course of ongoing renal injury and renal functional deterioration.  相似文献   
999.
The aims of this retrospective study were to consider the diagnostic role of dual-time 18F-fluorodeoxyglucose positron emission tomography and computed tomography (18F-FDG PET/CT) in detection of breast carcinoma and axillary lymph node (ALN) status and to evaluate the primary tumor 18F-FDG uptake pattern. Preoperative staging was performed by 18F-FDG PET/CT in 78 female patients with breast carcinoma. Conventional imaging results were evaluated by breast magnetic resonance imaging (MRI) of 79 lesions in 78 patients, bilateral mammography (MMG) of 40 lesions in 40 patients, and breast ultrasonography (USG) of 47 lesions in 46 patients. The primary tumor detection rate using 18F-FDG PET/CT was higher than those using MRI, USG, and MMG. The sensitivity and specificity of 18F-FDG PET/CT scans for detecting multifocality were higher than those of MRI. The specificity of ALN metastasis detection with MRI was higher than that with 18F-FDG PET/CT, but 18F-FDG PET/CT had higher sensitivity. Higher 18F-FDG uptake levels were detected in patients with ALN metastasis, histologic grade 3, estrogen–progesterone-negative receptor status, lymphatic invasion, and moderate to poor prognostic groups. There was no statistical difference for the retention index in categorical pathological parameters except for progesterone-negative status. In conclusion, 18F-FDG PET/CT scans may be a valuable imaging technique for evaluating primary tumor and axillary status in staging breast carcinoma and 18F-FDG uptake may be a prognostic factor that indicates aggressive tumor biology and poor prognosis. Dual-time imaging in breast carcinoma staging may not be used for predicting pathological criteria and the aggressiveness of primary lesions.  相似文献   
1000.
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