Although some employees working for Seoul Metropolitan Subway Cooperation are working at the noisy workplaces, they has been excluded from Special Periodic Health Examination Program. And some workers complained of hearing loss or tinnitus. So, this study was carried out to investigate the prevalence rate of Noise Induced Hearing Loss of employees(10,792) working for Seoul Metropolitan Subway Cooperation. The number of subjects were total 10,792 with 10,355 men and 437 women. A questionnaire survey, otological examination, Rinne test, pure tone audiometric tests were performed and through the first and second screening audiometric examination, 605 workers were selected after excluding employees with past otologic problems, recent exposure to high level noise, and under medications. and the results were as follow; 1. Among 10,792 workers, 4 workers(0.037%) diagnosed as NIHL and 601 workers(5.56%) as early NIHL. As workers grew older, the prevalence rate of NIHL and early NIHL became more rising. 2. The prevalence rate of NIHL and early NIHL was different between work site. After age adjustment, The prevalence rate of NIHL and early NIHL was 23.74% in Train repairmen{80dB(A)}, 3.1% in Station staffs{below 70dB(A)}, 2.53% in Train crew{below 70dB(A)}, 2.1% in Office workers. 3. The perception rate of necessities of ear plug in NIHL and early NIHL was below 55% and wearing rate of ear plug in NIHL and early NIHL was 1.1% In conclusion, some employees who was under working environment in Seoul Metropolitan Subway Cooperation should be monitored to prevent hearing impairment and would be needed health education.
Ear ; Female ; Health Education ; Hearing Loss* ; Hearing* ; Humans ; Male ; Mass Screening ; Noise* ; Prevalence ; Railroads* ; Seoul* ; Tinnitus ; Workplace ; Surveys and Questionnaires

BACKGROUND: The purpose of this study was to evaluate the postoperative magnetic resonance imaging (MRI) results of minimal-tying (one medial-row tie among 4 medial-row sutures) on the medial-row in double-row suture-bridge configuration (2x2 anchor with 4x4 suture stands). METHODS: From 2011 March to 2012 July, 79 patients underwent arthroscopic rotator cuff repair using 2x2 anchor double-row configuration. The mean age was 61.3 years (range, 31-81 years). Two double-loaded suture anchors were used for medial-row. Four medialrow stitches were made with only one medial-row knot-tying (the most anterior suture). Lateral-row was secured using the conventional suture-bridge anchor technique; all 4 strands were used for each anchor. Repair integrity was evaluated with MRI at mean 6.2 months postoperatively. Retear and the pattern of retear, change of fatty infiltration, and muscle atrophy of supraspinatus were evaluated using pre- and postoperative MRI. RESULTS: Repaired tendon integrity was 38 for type I, 30 for type II, 6 for type III, 4 for type IV, and 1 for type V, according to Sugaya classification. Considering type IV/V as retear, the rate was 6.3% (5 out of 79 patients). Medial cuff failure was observed in 4 patients. Fatty atrophy of supraspinatus was significantly improved postoperatively according to Goutallier grading (p=0.01). The level of muscle atrophy of supraspinatus was not changed significantly after surgery. CONCLUSIONS: Minimal tying technique with suture configuration of four-by-four strand double-row suture-bridge yielded a lower retear rate (6.3%) in medium to large rotator cuff tears.
Arthroscopy ; Atrophy ; Classification ; Humans ; Magnetic Resonance Imaging ; Muscular Atrophy ; Rotator Cuff* ; Shoulder ; Suture Anchors ; Sutures ; Tears* ; Tendons

Severe tooth wear may lead to pathological changes of pulp, imbalance in occlusion as well as functional and esthetic problems. In this case, 34-year-old male came to the hospital because of generally worn dentition due to attrition and erosion. After evaluation, a full mouth restoration with elevation of the vertical dimension of occlusion was planned. After occlusion was stabilized by an occlusal stabilization appliance, centric relation position was recorded and subsequent provisional restorations were fabricated. After evaluation, a CAD-CAM (computer aided design-computer aided manufacturing) prosthetic restoration was carried out using monolithic zirconia. After 12 months of follow up observation, the patient was satisfied with function and esthetic appearance.
Adult ; Bruxism ; Centric Relation ; Computer-Aided Design ; Dentition* ; Follow-Up Studies ; Humans ; Male ; Mouth ; Rehabilitation* ; Tooth Wear ; Vertical Dimension

A mandibular continuity defect can be repaired using either a prosthetic device or autogenous bone. A titanium reconstruction plate can be used with a localized or vascularized flap over the defect of the mandible. Unfortunately, the plate may fail due to plate exposure, screw loosening, fracture, or infection, and will need to be removed. Plate exposure though the skin or mucosa is one of the main reasons for failure. In the present work, the authors introduced a lingually positioned reconstruction plate fabricated via three-dimensional printed bending support. This custom reconstruction plate can avoid plate re-exposure as well as reduce surgical errors and operation time.

A mandibular continuity defect can be repaired using either a prosthetic device or autogenous bone. A titanium reconstruction plate can be used with a localized or vascularized flap over the defect of the mandible. Unfortunately, the plate may fail due to plate exposure, screw loosening, fracture, or infection, and will need to be removed. Plate exposure though the skin or mucosa is one of the main reasons for failure. In the present work, the authors introduced a lingually positioned reconstruction plate fabricated via three-dimensional printed bending support. This custom reconstruction plate can avoid plate re-exposure as well as reduce surgical errors and operation time.

No abstract available.

STATEMENT OF PROBLEM: Porcelain veneers have become a popular treatment modality for aesthetic anterior prosthesis. Fitting porcelain veneers in the mouth usually involve a try-in appointment, which frequently results in salivary contamination of fitting surfaces. PURPOSE: An in vitro study was carried out to investigate the effect of silane treatment timing and saliva contamination on the resin bond strength to porcelain veneer surface. MATERIAL AND METHODS: Cylindrical test specimens (n = 360) and rectangular test specimens (n = 5) were prepared for shear bond test and contact angle analysis. Whole cylindrical specimens divided into 20 groups, each of which received a different surface treatment and/or storage condition. The composite resin cement stubs were light-polymerized onto porcelain adherends. The shear bond strengths of cemented stubs were measured after dry storage and thermocycling (3,000 cycles) between 5 and 55 degrees C. The silane and their reactions were chemically monitored by using Fourier Transform Infrared Spectroscopy analysis (FTIR) and contact angle analysis. One-way analysis of variance (ANOVA) and Dunnett' multiple comparison were used to analyze the data. RESULTS: FT-IR analysis showed that salivary contamination and silane treatment timing did not affect the surface interactions of silane. Observed water contact angles were lower on the saliva contaminated porcelain surface and the addition of 37 percent phosphoric acid for 20 seconds on saliva contaminated porcelain increased the degree of contact angle. Silane applied to the porcelain, a few days before cementation, resulted in increasing the bond strength after thermocycling. CONCLUSION: Within the limitation of this study, it can be concluded that it would be better to protect porcelain prosthesis before saliva contamination with silane treatment and to clean the contaminated surface by use of phosphoric acid.
Cementation ; Dental Porcelain ; Mouth ; Phosphoric Acids ; Prostheses and Implants ; Resin Cements ; Saliva ; Spectroscopy, Fourier Transform Infrared ; Water

Kissing aneurysms are the rare type of multiple aneurysms. They are adjacent aneurysms of different origin arteries in the same region, which require great care in diagnosis and treatment. We report a case of kissing aneurysms at the anterior communicating artery (AcomA) which were treated by endovascular coil embolization.
Aneurysm ; Arteries ; Subarachnoid Hemorrhage

PURPOSE: In this paper we tried to evaluate the most appropriate surface for rhBMP-2 coating among 4 rough titanium surfaces. MATERIALS AND METHODS: We used machined surface as a control group and anodized, RBM and SLA surfaces as test groups. We coated rhBMP-2 on the 4 surfaces and with uncoated surfaces for each case, we cultured human mesenchymal stem cells on all 8 surfaces. 24 hours after we measured the stem cell'attachment with SEM, and on 3rd, 7th, and 14th days, we checked the cell proliferation and differentiation by using MTT and ALP activity assay. And on the 7th day after the culture, we performed RT-PCR assay to determine whether the expression levels of Type I collagen, osteocalcin, osteopontin were changed. RESULTS: We observed with SEM that 4 rhBMP-2 coated surfaces exhibited wider and tighter cell attachment and more cell process spreading than uncoated surfaces. The anodized rhBMP-2 surface caused robustest effects. In MTT assay we could not find any meaningful difference. In ALP assay there was a significant increase (P<.05) in the ALP activity of anodized rhBMP-2 coated surface compared with that of the control (3rd and 14th days) and with that of the RBM rhBMP-2 coated surface (14th day). In RT-PCR assay there was increased expressions in the anodized rhBMP-2 coated surface for osteocalcin, and osteopontin. CONCLUSION: We found that the anodized rhBMP-2 coated surface were most prominent stem cell attachment and differentiation in compared to control and Machined rhBMP-2 coated, RBM rhBMP-2 coated surface.
Cell Proliferation ; Collagen Type I ; Humans ; Mesenchymal Stromal Cells ; Osteocalcin ; Osteopontin ; Stem Cells ; Titanium

STATEMENT OF PROBLEM: Microleakage at the occlusal and gingival margin of Class V cavities restored with composite resin has traditionally been considered an obstacle to successful restoration. PURPOSE: The aim of this study was to assess the effectiveness of three different surface sealants(Fortify, Permaseal and Biscover LV) on the marginal sealing of Class V light-activated composite resin restorations(Z250). MATERIAL AND METHODS: Forty noncarious human premolars and molars extracted within a three-month period were selected. Class V cavities with the occlusal margin in enamel and gingival margin in cementum were prepared in both buccal and lingual surfaces. The teeth, randomly assigned in four groups with twenty cavities in each group, were restored with composite resin after applying an adhesive system(Clearfil SE bond). After the finishing and polishing procedures, the restorations were covered with a specific surface sealants, except for the control samples, which were not sealed. After placing restorations, the specimens were thermocycled, and immersed in a 2% methylene blue solution for twenty four hours and sectioned longitudinally. The marginal microleakage was evaluated at the occlusal and gingival interfaces using a microscope and compared among the four groups using ANOVA test and Wilcoxon Rank-Sum test(alpha=0.05). RESULTS: Statistical analysis showed that there was significantly less leakage when the surface sealants were used than there was in control group (P < .05). There were no significant differences of microleakage at occlusal and gingival margins among groups. There were no significant differences between microleakage of occlusal and gingival margins in each group. Fortify was not statistically different from control group at the gingival margin (P > .05). CONCLUSION: Application of surface sealants was an effective method of surface coating in reducing microleakage at occlusal and gingival margins of Class V composite resin restorations. However, it is certain that some microleakage still occurred despite the application of surface sealants, especially gingival margins.
Acrylates ; Adhesives ; Bicuspid ; Dental Cementum ; Dental Enamel ; Humans ; Methylene Blue ; Molar ; Resin Cements ; Tooth