Orthodontic bracket bonding to glazed full-contour zirconia

OBJECTIVES: This study evaluated the effects of different surface conditioning methods on the bond strength of orthodontic brackets to glazed full-zirconia surfaces. MATERIALS AND METHODS: Glazed zirconia (except for the control, Zirkonzahn Prettau) disc surfaces were pre-treated: PO (control), polishing; BR, bur roughening; PP, cleaning with a prophy cup and pumice; HF, hydrofluoric acid etching; AA, air abrasion with aluminum oxide; CJ, CoJet-Sand. The surfaces were examined using profilometry, scanning electron microscopy, and electron dispersive spectroscopy. A zirconia primer (Z-Prime Plus, Z) or a silane primer (Monobond-S, S) was then applied to the surfaces, yielding 7 groups (PO-Z, BR-Z, PP-S, HF-S, AA-S, AA-Z, and CJ-S). Metal bracket-bonded specimens were stored in water for 24 hr at 37℃, and thermocycled for 1,000 cycles. Their bond strengths were measured using the wire loop method (n = 10). RESULTS: Except for BR, the surface pre-treatments failed to expose the zirconia substructure. A significant difference in bond strengths was found between AA-Z (4.60 ± 1.08 MPa) and all other groups (13.38 ± 2.57 - 15.78 ± 2.39 MPa, p < 0.05). For AA-Z, most of the adhesive remained on the bracket. CONCLUSIONS: For bracket bonding to glazed zirconia, a simple application of silane to the cleaned surface is recommended. A zirconia primer should be used only when the zirconia substructure is definitely exposed.

Environmental and Familial Risk Factors of Children and Adolescents with Attention Deficit/Hyperactivity Disorder / 신경정신의학

OBJECTIVES: The aim of this study was to analyze the environmental and familial variables associated with attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. METHODS: Children and adolescents aged 6-18 with in attention, hyperactivity, or impulsivity who visited the Department of Psychiatry at Soonchunhyang University Bucheon Hospital from April 2006 to April 2012, were interviewed for diagnosis of ADHD. Diagnostic and Statistical Manual of Mental Disorders, 4th edition symptom criteria for ADHD were assessed using a semi-structured interview, the schedule for affective disorders and schizophrenia for school-age children present and lifetime version (K-SADS-PL). Environmental and familial variables were obtained using questionnaires for parents. RESULTS: In total, 262 children and adolescents with ADHD (n=139) and control subjects (n=123) were recruited. In a multivariate logistic regression model, results of this study showed that maternal psychiatric problem during pregnancy, dystoia, forceps/vacuum use during delivery, and unplanned pregnancy were risk factors for ADHD. CONCLUSION: Findings of this study showed an association of some prenatal factors (such as unplanned pregnancy or maternal psychiatric problem during pregnancy) and some perinatal factors (dystocia and forceps/vacuum use during delivery) with increased risk of ADHD. The identified risk factors are environmental, and therefore potentially preventable. Conduct of further prospective studies is needed in order to clarify the potential role of these risk factors for ADHD.

Factors affecting patients decision-making for dental prosthetic treatment / 대한치과보철학회지

STATEMENT OF PROBLEM: Factors affecting patients' decision-making for dental prosthetic treatment should be examined in terms of understanding improving patients' oral health. PURPOSE: The main purpose of this dissertation was to investigate patients' dental prosthetic treatment and factors affecting patients' decision-making for dental prosthesis treatment in Deagu and Gyungbook areas. MATERIAL AND METHODS: This study was based on the preliminary survey of dental patients conducted from July 1 to August 31 in 2006. A total of 700 questionnaires had been distributed and 640 were collected. 629 questionnaires were used for the statistical analysis. Descriptive and inferential statistics, such as frequencies, cross tabulation analysis, correlation analysis, logistic regression analysis, and multiple regression analysis were introduced. In the multiple regression analysis and logistic regression analysis, twenty-two independent variables were employed to explore the factors which have impacts on decision-making and satisfaction. RESULTS: The results of this dissertation are as follows: Logistic regression analysis turned out that monthly income, age, degree of expectation, marital status, and employer-insured policy of national insurance statistically increased the odds of decision-making of dental prosthesis treatment. But educational attainment decreased the odds ratio of the decision-making of dental prosthesis treatment. However, the rest independent variables do not have statistically significant impacts on the decision-making of dental prosthesis treatment CONCLUSION: Among independent variables, marital status had the most significant influence on the decision making of dental prosthesis treatment. Finally, suggestions for the future study and policy implications to improve satisfaction of the patients' dental prosthetic treatment were discussed.