• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.19-29
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• 1993

The static tensile tests of GFRP, ID300, CFRID300 and CFRPEEK were made on the plain and notched specimens at room temperature. The results were discussed based on linear notch mechanics which was proposed by H.Nistani. The fracture of notched GFRP, ID300, CFRID300 and CFRPEEK specimens is controlled by the elastic maximum stress, $({\sigma}_max)$, and the notch root racius,$\rho$, alone, independently of the other geometrical conditions. The relation between fracture nominal stress,$({\sigma}_max)$, and stress concentration factor, $K_t$ and a part where $({\sigma}_c)$ is nearly constant independent of $K_t$. A similar phenomenon can be seen in the fatigue tests of notched specimes under rotating bending or push-pull. The almost constant $({\sigma}_c)$ values correspond to the nearly constant apparent stress intensity factor, $K_{1pc}$ values, obtained by assuming ,$\rho$=0. This can be attributed to the existence of the stable crack. Linear notch mechanics is very useful for analyzing the static tensile fracture behavior of notched GFRP, ID300, CFRPEEK specimens.

• Imaging Science in Dentistry
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• v.44 no.2
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• pp.103-113
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• 2014

Purpose: In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. Materials and Methods: In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Results: Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. Conclusion: The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.5
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• pp.224-230
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• 2013

Objectives: Papilloma frequently develops as a benign tumor of the head and neck area, but its potential for malignant transformation has yet to be studied. This study aims to provide basic information for papillomas using the immunohistochemical staining of matrix metalloproteinase 2 (MMP-2) and human papilloma virus (HPV) 16 and 18. Materials and Methods: To evaluate the malignant transformation of papillomas, the selected tissue samples were serially diagnosed with pre-cancerous papilloma (with epithelial dysplasia, pseudo-epitheliomatous hyperplasia) or malignant lesion (squamous cell carcinoma, SCC) after the first diagnosis (squamous papilloma, inverted papilloma). The selected tissues were stained with an antibody to MMP-2 and HPV 16-E7, HPV 18-L1. A statistical analysis was performed according to each transformation step. Results: The epithelial layer of papilloma and pre-cancerous papilloma lesions had a similar MMP-2 expression, but that of the malignant lesion had a significantly increased MMP-2 expression. HPV 16 and 18 infection rates were 28.6%, 33.3% and 63.6% in papillomas, pre-cancerous papilloma lesions, and SCC. Conclusions: A relatively high MMP-2 expression and HPV 16 or 18 infection of papillomas may be associated with early events in the multistep processes of malignant transformation of papillomas.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.3
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• pp.103-106
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• 2018

Objectives: The goal of the study was to investigate the clinical effects of amoxicillin-clavulanic acid (500+125 mg) with metronidazole 400 mg administered three times daily (Group I) versus azithromycin 500 mg administered once daily and with metronidazole 400 mg three times daily (Group II) for the prevention of postoperative infection following mandibular third molar surgical removal. Materials and Methods: The study design was a single-center prospective study. Patients who reported to the Department of Oral and Maxillofacial Surgery between February 2015 and January 2017 for removal of mandibular third molar were screened, and 108 patients were chosen. One surgeon carried out all procedures. Patients were prescribed antibiotics until the two groups contained a similar number of cases. Results: Our data showed that Group II had fewer incidences of surgical site infection, but with no statistical significance. Conclusion: Although both treatments are used routinely after removal of the mandibular third molar, neither is significantly better than the other.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.5
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• pp.232-236
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• 2018

Objectives: Hormonal changes during menopause alter a woman's susceptibility to some disorders. Information regarding the prevalence of temporomandibular disorder (TMD) in menopausal women is limited in the literature. In this study, the prevalence and severity of TMDs were compared between menopausal and non-menopausal women. Materials and Methods: The study included 140 women (69 premenopausal and 71 postmenopausal) 45 to 55 years of age that were examined in Shiraz Dental School, Shiraz in Iran. The Helkimo clinical dysfunction index (Di) was used to evaluate temporomandibular joint (TMJ) dysfunction. The data were analyzed using chi-square and Fisher's exact tests. Results: Occurrence of TMD was significantly higher in menopausal than non-menopausal women (P<0.001). All the TMD criteria based on Helkimo Di except range of mandibular movement were significantly more common in menopausal women. The range of mandibular movement was not significantly different between menopausal and non-menopausal women (P=0.178). Conclusion: The results from this study show that TMD can be considered more common and severe in menopausal than non-menopausal women. This finding indicates that, similar to other conditions in menopausal women such as arthritis and osteoporosis, TMD should be taken into consideration by dental and medical professionals.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.5
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• pp.237-241
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• 2018

Objectives: The aim of this study was to determine the rate of peer-reviewed publication of abstracts presented at the annual meetings of the Turkish Association of Oral and Maxillofacial Surgeons (TAOMS) and to identify the time to publication, subspecialty, and study design. Materials and Methods: All abstracts accepted for presentation at a TAOMS meeting between 2007 and 2009 were identified from a book of abstracts and were searched for publication using PubMed and Google Scholar. The following variables were evaluated: publication rate, type of presentation (oral or poster), time to publication, subspecialty, study design, and name of the journal in which the article was published. Results: A total of 478 abstracts were presented at the TAOMS meetings between 2007 and 2009. Of these, 140 abstracts (29.3%) were subsequently published in peer-reviewed journals, including 38.2% of oral presentations and 26.6% of poster presentations. The mean time from presentation to publication was 22 months. Regarding publication fields, research and emerging technologies presentations had the highest publication rate (100%). With regard to study type, animal study (70.0%) and basic research (55.0%) had the highest publication rates. Conclusion: Only 29.3% of abstracts presented at the TAOMS meeting were subsequently published as full-text articles. This rate was found to be similar to the previously reported publication rates in the field of oral and maxillofacial surgery.

• The Journal of Advanced Prosthodontics
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• v.9 no.6
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• pp.432-438
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• 2017

PURPOSE. The purpose of this study was to evaluate the in vitro validity of quantitative light-induced fluorescence-digital (QLF-D) and laser fluorescence (DIAGNOdent) for assessing proximal caries in extracted premolars, using digital radiography as reference method. MATERIALS AND METHODS. A total of 102 extracted premolars with similar lengths and shapes were used. A single operator conducted all the examinations using three different detection methods (bitewing radiography, QLF-D, and DIAGNOdent). The bitewing x-ray scale, QLF-D fluorescence loss (${\Delta}F$), and DIAGNOdent peak readings were compared and statistically analyzed. RESULTS. Each method showed an excellent reliability. The correlation coefficient between bitewing radiography and QLF-D, DIAGNOdent were -0.644 and 0.448, respectively, while the value between QLF-D and DIAGNOdent was -0.382. The kappa statistics for bitewing radiography and QLF-D had a higher diagnosis consensus than those for bitewing radiography and DIAGNOdent. The QLF-D was moderately to highly accurate (AUC = 0.753 - 0.908), while DIAGNOdent was moderately to less accurate (AUC = 0.622 - 0.784). All detection methods showed statistically significant correlation and high correlation between the bitewing radiography and QLF-D. CONCLUSION. QLF-D was found to be a valid and reliable alternative diagnostic method to digital bitewing radiography for in vitro detection of proximal caries.

• The Journal of Advanced Prosthodontics
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• v.9 no.6
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• pp.409-415
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• 2017

PURPOSE. Accurate information is essential in dentistry. The image information of missing teeth is used in optically based medical equipment in prosthodontic treatment. To evaluate oral scanners, the standardized model was examined from cases of image recognition errors of linear discriminant analysis (LDA), and a model that combines the variables with reference to ISO 12836:2015 was designed. MATERIALS AND METHODS. The basic model was fabricated by applying 4 factors to the tooth profile (chamfer, groove, curve, and square) and the bottom surface. Photo-type and video-type scanners were used to analyze 3D images after image capture. The scans were performed several times according to the prescribed sequence to distinguish the model from the one that did not form, and the results confirmed it to be the best. RESULTS. In the case of the initial basic model, a 3D shape could not be obtained by scanning even if several shots were taken. Subsequently, the recognition rate of the image was improved with every variable factor, and the difference depends on the tooth profile and the pattern of the floor surface. CONCLUSION. Based on the recognition error of the LDA, the recognition rate decreases when the model has a similar pattern. Therefore, to obtain the accurate 3D data, the difference of each class needs to be provided when developing a standardized model.

• Journal of Gastric Cancer
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• v.18 no.2
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• pp.152-160
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• 2018

Purpose: Totally laparoscopic gastrectomy (TLG) for advanced gastric cancer (AGC) is a technically and oncologically challenging procedure for surgeons. This study aimed to compare the oncologic feasibility and technical safety of TLG for AGC versus early gastric cancer (EGC). Materials and Methods: Between 2011 and 2016, 535 patients (EGC, 375; AGC, 160) underwent curative TLG for gastric cancer. Clinicopathologic characteristics and surgical outcomes of both patient groups were analyzed and compared. Results: Patients with AGC required a longer operation time and experienced more intraoperative blood loss than those with EGC did. However, patients from both the AGC and EGC groups demonstrated similar short-term surgical outcomes such as postoperative morbidity (14.4% vs. 13.3%, P=0.626), mortality (0% vs. 0.5%, P=0.879), time-to-first oral intake (2.7 days for both groups, P=0.830), and postoperative hospital stay (10.2 days vs. 10.1 days, P=0.886). D2 lymph node dissection could be achieved in the AGC group (95%), with an adequate number of lymph nodes being dissected ($36.0{\pm}14.9$). In the AGC group, the 3-year overall and disease-free survival rates were 80.5% and 73.7%, respectively. Conclusions: TLG is as safe and effective for AGC as it is for EGC.

• Journal of the Korean Society of Costume
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• v.53 no.4
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• pp.163-176
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• 2003

Waist lined Coat with Pleats excavated from Byun-su(1447-1524) Tomb in Yangpyeong were very similar in size to the costume of Haeina Temple which is the oldest YosunChollik up to now YosunChollik was popularly worn in the Yuan Dynasty of China(원) and it is presumed to be flown into Korea in that period. In China, the coat with a straight collar was called ByeonseonOh , and one with a round collar was called ByeonseonOhja in the Yuan Dynasty. The excavated relics of Haeinsa Temple are almost same as ByeonseonOh. In the Myoung Dynasty(명), the coat with a straight collar was called YoseonOhja, and one with a round collar was called Round collar YoseonOhja . The Waist lined Coat with Pleats excavated in the Byunsu Tomb is same as YoseonOhja Attendants who is low in position and doctors used to wear the coat, which was spread to diverse classes by degrees. Later, even emperors and high ranking officials used to wear it as military uniforms. It was made of silk and summer cloth. As mentioned above, 1 examined its history carefully through Chinese documents and photographic materials on relics. In addition, with the authentic records of Korea and the excavated relics of the Byun-su Tomb, 1 analyzed its components. However, the analysis was very restricted because the relics to be compared with were few.