OBJECTIVES: To evaluate the accuracy and consistency of two different apex locators at both the Apex and 0.5 marks. MATERIALS AND METHODS: Twenty-six root canals was scheduled for extraction for periodontal or prosthodontic reasons. Thirteen canals were measured using Root ZX and the rest by i-ROOT. The root canal length was measured both the at 0.5 mark and the Apex mark. The file was then fixed to the tooth, and the distance from the file tip to the major foramen of each canal was measured after removing the root dentin under the microscope so that the major foramen and the file tip were seen. RESULTS: 1. When the Apex mark was used, 100% of both the Root ZX and i-ROOT groups were within 0.5 mm of the major foramen. 2. When 0.5 mark was used, 100% of the Root ZX group and 77% of the i-ROOT group were within 0.5 mm of the major foramen. 3. In terms of standard deviation and quartile value, the Apex mark was more consistent than 0.5 mark in the Root ZX group, and 0.5 mark was more consistent in the i-ROOT group, but there was no statistically significant difference when compared with t-test. 4. The root canal length difference between the Apex mark and 0.5 mark was 0.22 mm and 0.46 mm in the Root ZX and i-ROOT groups, respectively. CONCLUSIONS: In this study, the Apex mark was the more consistent mark. Therefore, it is recommended to subtract 0.5 mm, which is the average length between the apex and apical constriction, from the root canal length at the Apex mark to obtain the working length clinically.
Constriction ; Dental Pulp Cavity ; Dentin ; Electronics ; Electrons ; Prosthodontics ; Tooth

The objectives of this study were to characterize the alterations of 3p and 9p in sporadic renal cell carcinomas (RCC) and to assess the relationship between the clinical stages or tumor size and the alteration of these chromosomes. Thirty eight archival, paraffin embedded tissue sections from 38 patients with RCC were analyzed for loss of heterozygosity (LOH) at 3p and 9p with 11 microsatellite markers. LOH was detected in 81.6% (31/38) and 37.8% (14/37) at 3p and 9p, respectively. The frequencies of LOH at VHL and FHIT locus were 75.6% and 72.2%, respectively. Twelve cases out of 38 showed LOH at both 9p21 and 3p. The loss of 3p in the samples tested was not related to clinical stages and tumor size, but that of 9p21 was significantly associated with advanced stage and larger tumor size. These results support that 3p deletion, including VHL and FHIT gene, play a critical role in the tumorigenesis of sporadic RCC, especially at early stage, and that 9p21 may contribute to the progression of sporadic RCC.
Carcinogenesis ; Carcinoma, Renal Cell* ; Humans ; Loss of Heterozygosity* ; Microsatellite Repeats ; Paraffin

BACKGROUND: In various studies in adults, caffeine may increase wakefulness and relieve pain, but caffeine overdose can cause many adverse serious effects on health. Caffeine intake has recently been increasing in adolescents. In spite of importance of caffeine effects on Korean adolescents, there are lack of scientific and systematic studies. The purpose of our study was to identify the relationship between caffeine consumption and effects on adolescents. METHODS: We performed study on 234 middle school students at one middle school in Daegu using a self-report questionnaire. We divided students to quartiles according to amount of caffeine intake. We used Beck Depression Inventory (BDI) to evaluate the degree of depression and Beck Anxiety Inventory (BAI) to evaluate the degree of anxiety. We also used Insomnia Severity Scale (ISI) to evaluate the degree of insomnia and Global Assessment of Recent Stress (GARS) to evaluate the stress in students. We used logistic regression analysis to identify the relationship between caffeine consumption and effects. RESULTS: Higher caffeine intake was associated with higher weight, height, lower academic achievement, and higher score in BDI, BAI, ISI, and GARS (P for trend <0.005). Higher caffeine intake quartile was associated with greater odds of having significant depression (BDI ≥10, P for trend=0.011), and insomnia (ISI ≥8, P for trend=0.015) after adjustment for factors that can affect the psychological status. CONCLUSION: We found that caffeine intake is associated weight, height, academic achievement, and higher score in BDI, BAI, ISI, and GARS. Caffeine intake was positively associated with the severity of depression and the severity of insomnia among adolescents in Korean.
Adolescent* ; Adult ; Anxiety* ; Caffeine* ; Daegu ; Depression* ; Humans ; Logistic Models ; Sleep Initiation and Maintenance Disorders ; Wakefulness