• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.36.1-36.17
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• 2022

Objectives: This study aimed to evaluate the effect of aging on the marginal quality of glass hybrid (GH) material used to elevate dentin gingival margins, and to analyze the consistency of the results obtained by 3 in vitro methods. Materials and Methods: Ten teeth received compound class II cavities with subgingival margins. The dentin gingival margins were elevated with GH, followed by resin composite. The GH/gingival dentin interfaces were examined through digital microscopy, scanning electron microscopy (SEM) using resin replicas, and according to the World Dental Federation (FDI) criteria. After initial evaluations, all teeth were subjected to 10,000 thermal cycles, followed by repeating the same marginal evaluations and energy dispersive spectroscopy (EDS) analysis for the interfacial zone of 2 specimens. Marginal quality was expressed as the percentage of continuous margin at ×200 for microscopic techniques and as the frequency of each score for FDI ranking. Data were analyzed using the paired sample t-test, Wilcoxon signed-rank test, and Pearson and Spearmen correlation coefficients. Results: None of the testing techniques proved the significance of the aging factor. Moderate and strong significant correlations were found between the testing techniques. The EDS results suggested the presence of an ion-exchange layer along the GH/gingival dentin interface of aged specimens. Conclusions: The marginal quality of the GH/dentin gingival interface defied aging by thermocycling. The replica SEM and FDI ranking results had stronger correlations with each other than either showed with the digital microscopy results.

• Radiation Oncology Journal
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• v.14 no.4
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• pp.317-322
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• 1996

Purpose : Patients with cervical cancer who have positive resection margins after radical hysterectomy are at increased risk for local recurrence. The result of postoperative pelvic radiotherapy for cervix cancer with positive resection margins were analyzed to evaluate the role of radiotherapy. Materials and Methods : Between n 1979 and 1992, 60 patients of cervix carcinoma were treated with postoperative radiotherapy after radical hysterectomy and pelvic lymphadenectomy because of positive vaginal (48 patients) or parametrial resection margins (12 patients). Patients were treated with external beam radiation therapy (EBRT) alone (12 Patients) or EBRT plus vaginal ovoid irradiation (VOI) (48 patients). The median followup period was 55 months. Results : The 5-year actuarial disease free and overall survival rates for all patients were $75.2\%$, $84.1\%$, respectively. The overall recurrence rate was $23\%$ (14/60). In 48 patients with Positive vaginal resection margins, the pelvic recurrence was $8\%$ (4/48). Distant metastasis was $15\%$(7/48). Of the 43 patients with positive vaginal resection margins treated with EBRT and VOI, recurrence rate was $21\%$(9/43) , while recurrence rate was $40\%$(2/5) in the EBRT only treated group. In 12 patients with positive parametrial margins, three patients ($25\%$) had distant metastases. The most significant prognostic factor was lymph node metastasis. Complications resulting from radiotherapy occurred at a rate of $32\%$(19/60) and grade III complications occurred in three patients ($5\%$). Conclusion : Postoperative radiotherapy can produce excellent pelvic control rates in patients with positive resection margins. In patients with positive vaginal margins, whole pelvic EBRT and VOI is recommended.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.53-61
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• 1999

Newley developed dentin bonding system which contains self-etching primer performed the removing of smear layer and etching procedure at once. So, it make possible more simple and shorter working time, the stronger bonding strength than conventional dentin bonding system. Cavities were prepared in the buccal and lingual surface of 30 extracted primary molars, and randomly assigned into three equal groups of 10 each. All cavities were filled with Z-100 composite resin following manufacturer's specifications after priming of three different dentin bonding system. Specimens stored for 7 days in 37 degree C water, thermocycled for 1000 cycles between 5 degree C and 55 degree C, immersed in 50% silvernitrate solution for 24 hours, and embedded in resin before being sectioned longitudinally. Data were analyzed by t-test and ANOVA. Mac-Bond II and Clearfil Linear-Bond II showed less microleakage at the occlusal and gingival margins compared to Scotchbond Multi Purpose. All dentin bonding systems showed significantly less microleakage at the occlusal margins compared to the gingival margins. But, there were no significantley difference between each group.

• Journal of Korean Neurosurgical Society
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• v.50 no.6
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• pp.523-527
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• 2011

A 67-year-old woman presented for evaluation of severe coccygeal pain. The computed tomography scans and magnetic resonance imaging showed an asymmetric midline sacral tumor invading the right lower portion of S2. To preserve both S2 nerve roots and to obtain negative surgical margins, a modified mid-sacrectomy with an aid of a computed navigation system was performed. The sacral tumor was excised en bloc with negative tumor margins. Both S2 nerve roots were preserved and additional reconstruction was not necessary because of minimal resection of the sacroiliac joint. We report a case of a sacral chordoma which was excised en bloc with adequate surgical margins by a computer-assisted modified mid-sacrectomy. The computed navigation system may be a useful tool for tumor targeting and safe osteotomies in sacral tumor surgery via the posterior only approach.

• Progress in Superconductivity and Cryogenics
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• v.6 no.4
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• pp.41-45
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• 2004

Rapid Single flux quantum (RSFQ) confluence buffer is widely used in complex superconductive digital circuits. In this work, we have improved the currently used confluence buffer and obtained a more soundly designed confluence buffer. In simulations, improvements in the bias margins of 11 % and the global margins of 10%, compared to the previously used confluence buffer, were achieved. Global margins are very important in estimating a process error range allowed in fabrications. We used two circuit simulation tools, WRspice and Julia, to design and optimize the confluence buffer. We used Xic to obtain a mask layout. We fabricated the improved circuits by using Nb technology. The test results at low frequency showed that the improved confluence buffer operated correctly and had a very wide main bias margin of +/-43% enhanced from +/-26% of the previously used confluence buffer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2211-2215
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• 2014

Background: To examine the incidence of positive vaginal surgical margins and determine the predicting factors following radical hysterectomy for stage IB1 carcinoma of the cervix. Materials and Methods: The clinical and histological data of 656 FIGO stage IB1 cervical cancer patients who had radical hysterectomy with bilateral pelvic lymphadenectomy (RHPL) from January 2003 to December 2012 were retrospectively reviewed and were analyzed for their association with a positive vaginal surgical margin. A p-value of < 0.05 was considered significant. Results: Thirty-five patients (5.3%) had positive vaginal surgical margins following RHPL; 24 (3.7%) for intraepithelial lesions and 11 (1.7%) for carcinoma. On multivariate analysis, microscopic vaginal involvement by high-grade squamous intraepithelial lesion and/or carcinoma (adjusted odd ratio (OR) 186.8; 95% confidence interval (CI) 48.5-718.5) and squamous histology (OR 8.7; 95% CI 1.7-44.0), were significantly associated with positive vaginal surgical margin. Conclusions: Microscopic vaginal involvement by HSIL and/or carcinoma are strong predictors for positive vaginal surgical margins for stage IB1 cervical cancer patients undergoing radical hysterectomy. Preoperative 'mapping' colposcopy or other strategies should be considered to ensure optimal vaginal resection.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.621-628
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• 1997

This study aimed to quantify the impact of crossbreeding at farm level, in mixed farm systems in Gujarat. Households with crossbred cattle did not differ from households without crossbreds in terms of farm resources, crop gross margins and off-farm income. The use of crossbred animals did increase livestock gross margins by 64% and household income by 22%. The three agro-ecological zones included in this study differed considerably according to farm system and household income. However, in all three zones, households with crossbreds had higher livestock gross margins than households without crossbreds. There was no real difference in work load and labour division between households with and without crossbreds. There was also no difference in the use of bullocks for draught purposes between the two types of households. In particular buffaloes are being replaced by crossbred cattle. There was a large variation in farm income, largely because of land area. The milk offake per average cow and the number of buffaloes also related positively to farm income in both types of households. Crossbreeding has proved technically and financially viable in different Gujarat mixed farming systems. It can be concluded that crossbreeding is an important development option for landless farmers.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3317-3320
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• 2016

Purpose: To assess the success rates of two step loop electrosurgical excision procedure (LEEP) compared with conventional cold conization procedures for decreasing positive surgical margins. Materials and Methods: This study was conducted on 70 patients who underwent colposcopic evaluation in Zeynep Kamil Women and Children's Health Training and Research Hospital between 2013-2015 with indications of CIN 2/3 or persistent CIN 1 for more than 2 years. The study included age matched groups of patients with similar histopathololical lesions who underwent cold conization (n=40) or LEEP (N=30). Results: Comparison of tissue characteristics between the two groups revealed significantly higher deepest depth and lower volume of tissue removed by the two step LEEP. Ectocervical positivity rate was similar between groups (1/39 versus 0/29, P>0.05), while endocervical surgical margin positivity rate was significantly higher in the cold conization group (9/39 versus 0/29, P<0.05). Surgical margin positive cases were significantly older than the cases with negative margins (P<0.05). Conclusions: Two step LEEP made it easier to reach the squamocolumnar junction in the endocervical region with lower blood loss and applicability in office settings. Our study suggests to use two step approach in cases with high grade and glandular CIN.

• The Journal of Korean Academy of Prosthodontics
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• v.23 no.1
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• pp.113-123
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• 1985

The purpose of this study was to evaluate the marginal fitness of collarless metal-ceramic crown formed with direct lift technique using wax compared with metal-ceramic crown with metal butt margin. Twenty crowns, ten were collarless metal-ceramic crowns and ten were metal-ceramic crowns with metal butt margins, were made and cemented on epoxy resin dies, and their marginal openings were measured on scanning electron microphotographic prints at x200 magnification. The results were as follows; 1. In the case of collarless metal-ceramic crowns, the mean marginal opeining was $43.78{\pm}17.67{\mu}m$, the mean maximum marginal opening was $52.81{\pm}19.81{\mu}m$, and the mean minimum marginal opening was $34.99{\pm}16.58{\mu}m$. 2. In the case of metal-ceramic crowns with metal butt margins, the mean marginal opening was $47.62{\pm}25.55{\mu}m$, the mean maximum marginal opening was $61.90{\pm}24.39{\mu}m$, and the mean minimum marginal opening was $34.86{\pm}24.92{\mu}m$. 3. There was no significant difference between two types of crowns at the 99% confidence level. 4. The marginal fitness of collarless metal-ceramic crown formed with direct lift technique using wax was clinically acceptable.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.149-154
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• 2017

Computer-aided surgery (CAS) started being used for head and neck reconstruction in the late 2000s. Its use represented a paradigm shift, changing the concept of head and neck reconstruction as well as mandible reconstruction. Reconstruction using CAS proceeds through 4 phases: planning, modeling, surgery, and evaluation. Thus, it can overcome a number of trial-and-error issues which may occur in the operative field and reduce surgical time. However, if it is used for oncologic surgery, it is difficult to evaluate tumor margins during tumor surgery, thereby restricting pre-surgical planning. Therefore, it is dangerous to predetermine the resection margins during the presurgical phase and the variability of the resection margins must be taken into consideration. However, it allows for the preparation of a prebending plate and planning of an osteotomy site before an operation, which are of great help. If the current problems are resolved, its applications can be greatly extended.