Acetylcysteine ; pharmacology ; Antioxidants ; pharmacology ; Composite Resins ; toxicity ; Dental Materials ; toxicity ; Fibroblasts ; drug effects ; metabolism ; Gingiva ; cytology ; drug effects ; Humans ; Methacrylates ; toxicity ; Polyethylene Glycols ; toxicity ; Polymethacrylic Acids ; toxicity ; Polymethyl Methacrylate ; toxicity ; Reactive Oxygen Species ; metabolism ; Resins, Synthetic ; toxicity

Emerging technologies such as four-dimensional computed tomography (4D CT) is expected to allow clinicians to accurately model interfractional motion and to quantitatively estimate internal target volumes (ITVs) for radiation therapy involving moving targets. A need exists for a 4D radiation therapy quality assurance (QA) device that can incorporate and analyze the patient specific intrafractional motion as it relate to dose delivery and respiratory gating. We built a 4D RT prototype device and analyzed the patient-specific 4D radiation therapy QA for 2D dose distributions successfully. With more improvements, the 4D RT QA prototype device could be an integral part of a 4D RT decision process to confirm the dose delivery.
Four-Dimensional Computed Tomography ; Humans ; Polymethacrylic Acids

PURPOSE: This study evaluated the existence of golden proportion between the widths of the maxillary and mandibular anterior teeth in Indian population. MATERIALS AND METHODS: The clinical tooth width measurements were recorded with the digital vernier calipers on 576 patients of both sexes in the age group of 21 - 30 years. Flexible ruler was used to determine the width of maxillary and mandibular anterior teeth on the patients by the same operator. The data obtained was statistically analyzed using paired student t-test (alpha=.05). RESULTS: The golden proportion was not found between the width of the right central and lateral incisors in 53% of women and 47% of men. The results revealed the golden percentage was rather inconstant in terms of relative tooth width. CONCLUSION: The golden proportion is an inappropriate method to relate the successive widths of the maxillary anterior teeth in Indian population.
Female ; Humans ; Incisor ; Male ; Polymethacrylic Acids ; Tooth

Artificial corneas have been developed as an alternative to natural donor tissue to replace damaged or diseased corneas. This study was conducted to evaluate the stability and biocompatibility of PHEMA-PMMA [poly (2-hydroxyl methacrylate)-poly (methyl methacrylate)] keratoprostheses in rabbits following penetrating keratoplasty. Sixteen male New Zealand White rabbits aged 16 weeks were divided into three groups. Group I and group II contained six rabbits each, while the control group had four rabbits. Experimental surgery was conducted under general anesthesia. The cornea was penetrated using an 8 mm diameter biopsy punch. In group I (core 5 mm & skirt 3 mm) and group II (core 6 mm & skirt 2 mm), the keratoprosthesis was placed into the recipient full thickness bed and sutured into position with double-layer continuous. In the control group, corneal transplantation using normal allogenic corneal tissue was performed with the same suture method. After four and eight weeks, keratoprosthesis devices were evaluated by histopathological analysis of gross lesions. Post-operative complications were observed, such as extrusion and infection in experimental groups. Most corneas were maintained in the defect site by double-layer continuous suture materials for 4 weeks and kept good light transmission. However, most artificial cornea were extruded before 8 weeks. Overall, combined PHEMA and PMMA appears to have sufficient advantages for production of artificial corneas because of its optical transparency, flexibility and other mechanical features. However, the stability and biocompatibility were not sufficient to enable application in humans and animals at the present time using penetrating keratoplasty. Further studies are essential to improve the stability and biocompatibility with or without other types of keratoplasty.
Anesthesia, General ; Animals ; Biopsy ; Cornea ; Corneal Transplantation ; Humans ; Keratoplasty, Penetrating* ; Male ; Methods ; Pliability ; Polyhydroxyethyl Methacrylate ; Polymethyl Methacrylate ; Rabbits* ; Sutures ; Tissue Donors

The purpose of this study is to evaluate the change in condylar position, width, and angle before and after orthognathic surgery using 3-dimensional computed tomograph. Pre and posterative 3-D CT was taken on 38 patients and through axial, frontal, sagittal measurements and by 3-dimensional reconstruction, the changes in condylar postion, mandibular width and angle were analyzed and others such as the difference in gender, operation and fixation method, setback length and in relation with temporomandibular disorders were done together too. The results were as follows: The inward rotation of condyle in axial condylar angle, the forward movement of right condyle in sagittal anterior-posterior distance, the superior movement of both condyles in sagittal superior-inferior distance, the decrease in gonial angle, the increase in mandibular width, the decrease in distance between the axial coronoid process distance and the increase in the frontal intercondylar distance were statistically significant. There were no statistically significant changes in gender difference, however in the difference in operation method, change in the gonial angle was observed and there was more change in bilateral sagittal split osteotomy group compared to two-jaw surgery group. In the difference in fixation method, the decrease in axial coronoid process distance and the change in sagittal anterior-posterior distance were statistically significant. In the difference in setback, the increase in setback didn't relate directly with the increased change in condyle position. In the relation with temporomandibular disorder, changes in left axial condylar angle and axial coronoid process distance were statistically significant. Changes in condylar position could be observed after the orthognathic surgery but it doesn't seem to have much of a clinical importance. The orthognathic surgery is effective in decreasing the mandibular angle, and it is not related with the temporomandibular disorder.
Head ; Humans ; Orthognathic Surgery ; Osteotomy ; Polymethacrylic Acids ; Temporomandibular Joint Disorders

Management of posttraumatic enophthalmos can present as a challenge to the reconstructive surgeon, particularly in cases of late presentation. This article reviews the pertinent anatomy of the orbit, diagnostic modalities, indications for surgery, and surgical approaches as they relate to the treatment of posttraumatic enophthalmos. Internal orbital reconstruction has evolved to an elegant procedure incorporating various biologic or alloplastic implants, including anatomical pre-bent implants. Successful repair of late enophthalmos has been demonstrated in multiple recent studies and is likely related to the precision with which orbital anatomy can be restored.
Enophthalmos ; Orbit ; Orbital Fractures ; Orbital Implants ; Polymethacrylic Acids

BACKGROUND: This study evaluated how the alcohol drinking motives and alcohol drinking expectancies, as the internal factors, would relate to university students' alcohol drinking problems. METHODS: The general characteristics, the alcohol drinking problems, the motives to drink, and drinking expectancy were surveyed with 197 university students (106 males, 91 females) who visited the Health Center of Chungnam National University. RESULTS: The alcohol drinking amount per drink (P < 0.001), weekly alcohol drinking frequency (P < 0.001), alcohol drinking problem score (P < 0.001), the score of drinking expectancy (P < 0.001) and motives to drink for each domain (P < 0.05) for male students were significantly higher or larger than those of the female students. The distribution of the number of binge, heavy and at risk drinkers didn't show significant difference between sexes. The drinking problem score, the score of drinking expectancy and motives to drink for each domain showed significant (P < 0.001) positive correlation and male students displayed a higher positive correlation than that of female. Stepwise multiple regression analysis was conducted to evaluate the influence on drinking problem score. The male students' drinking problem score was associated with the score of coping motive, lower grade, the score of enhancement motive and drinking expectancy (R2, 0.325; P < 0.05) whereas those of female students were related to the score of social and coping motive (R2, 0.477; P < 0.001). CONCLUSION: The common factor that related to drinking problem for both male and female students was the coping motive to resolve negative feeling. In addition, the enhancement motive and drinking expectancy in male students and the social motive in female students were the associated factors.
Alcohol Drinking ; Drinking ; Female ; Humans ; Male ; Polymethacrylic Acids

BACKGROUND: This study evaluated how the alcohol drinking motives and alcohol drinking expectancies, as the internal factors, would relate to university students' alcohol drinking problems. METHODS: The general characteristics, the alcohol drinking problems, the motives to drink, and drinking expectancy were surveyed with 197 university students (106 males, 91 females) who visited the Health Center of Chungnam National University. RESULTS: The alcohol drinking amount per drink (P < 0.001), weekly alcohol drinking frequency (P < 0.001), alcohol drinking problem score (P < 0.001), the score of drinking expectancy (P < 0.001) and motives to drink for each domain (P < 0.05) for male students were significantly higher or larger than those of the female students. The distribution of the number of binge, heavy and at risk drinkers didn't show significant difference between sexes. The drinking problem score, the score of drinking expectancy and motives to drink for each domain showed significant (P < 0.001) positive correlation and male students displayed a higher positive correlation than that of female. Stepwise multiple regression analysis was conducted to evaluate the influence on drinking problem score. The male students' drinking problem score was associated with the score of coping motive, lower grade, the score of enhancement motive and drinking expectancy (R2, 0.325; P < 0.05) whereas those of female students were related to the score of social and coping motive (R2, 0.477; P < 0.001). CONCLUSION: The common factor that related to drinking problem for both male and female students was the coping motive to resolve negative feeling. In addition, the enhancement motive and drinking expectancy in male students and the social motive in female students were the associated factors.
Alcohol Drinking ; Drinking ; Female ; Humans ; Male ; Polymethacrylic Acids

PURPOSE: This study firstly examined the pattern and prevalence of drinking. Secondly, we investigated the association between various psychosocial work environment and problem drinking among Korean male workers in different age groups. METHODS: The study sample was a weighted population of 3,289 (3,289 survey samples) men aged 20 to 64 years who responded to the 2006 Korean Working Condition Survey. Social support from colleague and supervisor, work autonomy, psychological wellbeing at work, and intellectual and emotional work demand were assessed. RESULTS: After considering sociodemographic factors, smoking, occupational characteristics and other psychosocial work environment factors, problem drinking was associated with "intellectual work demand" for the 20~34 year old group. Social support from colleague and supervisor was significantly associated with problem drinking in the 35~49 year old group. For the 50~64 year old group, problem drinking was associated with 'work autonomy'. CONCLUSION: The present study clarified that certain psychosocial work environmental factors relate to problem drinking, and the association varies among different age groups.
Aged ; Drinking ; Humans ; Male ; Polymethacrylic Acids ; Prevalence ; Smoke ; Smoking

STATEMENT OF PROBLEM: An incompatibility between the initiator systems of self-curing composite resins and light-curing adhesives was supposed recently. PURPOSE: The purpose of the study was to evaluate the influence of activators for self/dual bonding on dentin shear bonding strengths. MATERIAL AND METHODS: Fifty human molars were divided into 5 groups. A flat dentin surface was created for each tooth. A self-curing composite resin (Luxacore) was bonded with the following adhesives (n = 10): One-Step, Prime and Bond NT, AdheSE, Prime and Bond NT and AdheSe were also used in combination with activators. Shear bond strengths were measured after 24 hours of water storage. The specimens were loaded in shear in the Instron until failure at a 1 mm/min crosshead speed. Data were compared using one-way ANOVA and Tukey HSD test (alpha = 0.05). RESULTS: The dentin adhesive systems in order of decreasing median bond strength were One-Step > Prime & Bond NT with activator, AdheSe with activator > Prime and Bond NT, AdheSe. Among adhesives, One-Step had the highest bond strength. Prime & Bond NT with activator had higher bond strengths than Prime and Bond NT that was used alone, and so was AdheSe. CONCLUSION: Shear bond strengths were increased in Prime and Bond NT and AdheSe when these were used with activators comparing used without activators. But using activators was not effective clinically comparing One-Step.
Adhesives ; Composite Resins ; Dentin ; Humans ; Molar ; Polymethacrylic Acids ; Tooth ; Water