The effect of additional etching and curing mechanism of composite resin on the dentin bond strength

PURPOSE: The aim of this study was to evaluate the effects of additional acid etching and curing mechanism (light-curing or self-curing) of a composite resin on the dentin bond strength and compatibility of one-step self-etching adhesives. MATERIALS AND METHODS: Sixteen human permanent molars were randomly divided into eight groups according to the adhesives used (All-Bond Universal: ABU, Clearfil S3 Bond: CS3), additional acid etching (additional acid etching performed: EO, no additional acid etching performed: EX), and composite resins (Filtek Z-250: Z250, Clearfil FII New Bond: CFNB). Group 1: ABU-EO-Z250, Group 2: ABU-EO-CFNB, Group 3: ABU-EX-Z250, Group 4: ABU-EX-CFNB, Group 5: CS3-EO-Z250, Group 6: CS3-EO-CFNB, Group 7: CS3-EX-Z250, Group 8: CS3-EX-CFNB. After bonding procedures, composite resins were built up on dentin surfaces. After 24-hour water storage, the teeth were sectioned to make 10 specimens for each group. The microtensile bond strength test was performed using a microtensile testing machine. The failure mode of the fractured specimens was examined by means of an optical microscope at x20 magnification. The data was analyzed using a one-way ANOVA and Scheffe's post-hoc test (alpha=.05). RESULTS: Additional etching groups showed significantly higher values than the no additional etching group when using All-Bond Universal. The light-cured composite resin groups showed significantly higher values than the self-cured composite resin groups in the Clearfil S3 Bond. CONCLUSION: The additional acid etching is beneficial for the dentin bond strength when using low acidic one-step self-etch adhesives, and low acidic one-step self-etch adhesives are compatible with self-cured composite resin. The acidity of the one-step self-etch adhesives is an influencing factor in terms of the dentin bonding strength and incompatibility with a self-cured composite resin.

The Effects of Green Tea Extracts (Polyphenon E, EGCG) in Human Papilloma Virus Positive Cervical Lesion / 대한산부인과학회잡지

OBJECTIVE: We tried to confirm the effects of green tea extracts (polyphenon E, EGCG) in patients with human papilloma virus (HPV) positive cervical lesion. METHODS: We divided 51 HPV positive cervical lesion patients (chronic cervicitis, mild dysplasia, moderate dysplasia and severe dysplasia) into 4 group and 37 patient as placebo control. We applied poly E ointment two times per week (27 patients), poly E ointment plus poly E capsule (8 patients), poly E capsule (6 patients), EGCG capsule (10 patients) 200 mg each for 8 to 12 weeks. RESULTS: Among 27 patients with poly E ointment group, 20 patients responded (74%), such as chronic cervicitis (12/18), mild dysplasia (4/5), moderate dysplasia (2/2) and severe dysplasia (1/2). Among 8 patients with poly E ointment and poly E capsule group, 6 patients responded (75%), 6 patients poly E capsule group responded 3 patients (50%). 10 EGCG capsule patients group responded 6 patients (60%). Overall responsive rate is 69% (35/51) in case of green tea extracted treated group and 10% (4/39) in placebo controlled group (P<0.05). CONCLUSION: The effects of green tea extract in HPV positive cervical lesion were statistically significant (P<0.05). This result suggests that green tea extract has highly potential of new treatment agent for HPV infected cervical lesion.

Relationship between stress amounts and health habits about nurses in one hospital

BACKGROUND: Stress is found to have influence on physical and mental disorders, and also to healthy life habits related to physical health mental stress. Job holders are groups that have suffered from chronic stressful condition. Consider medical people of job holders to received exess stress. So, we tested this investigation to know the relationship between health habits and stress amounts about nurse. METHODS: This study was performed on nurses who worked on one hosptal in Pusan Metropolitan city for one months(from April, 1, to April, 30, 2000). We used 128 results. Health habits were investigated about 5 articles out of "Breslow's 7 health habits" and stress amounts were measured by Korean translated BEPSI(Brief Encounter Psychosocial Instrument) and Bae Jong Myun's 30 items SRRQ(Social Readjustment Rating Questionnaire). RESULTS: There were differences in amounts of stress of subjects according to marital state(P<0.05), job department(P<0.05), BMI(Body Mass Index)(P<0.05), sleeping time(P<0.05). CONCLUSION: This investigation has showed that having excess stress in nurses. Body Mass Index, sleeping time appeared to be health habits related to amounts of stress.