Perceptual and quantitative analysis of discoloration of orthodontic elastomeric chains by food.

BACKGROUND: The objectives of this study were to use a digital camera to measure the discoloration of orthodontic elastomeric chains in various immersion solutions over different time periods and to determine the valid acceptability tolerances for color changes in orthodontic elastomeric chains by surveying digital photographs. METHODS: Orthodontic elastomeric chains were applied to the maxillary anterior teeth of nine typodont models. The models were divided into three groups and immersed in the curry, coffee, and wine solutions. The digital images of the elastomeric modules were captured and processed using commercial software after 30 min of immersion, thrice a day, for 28 days. The differences in color changes ([Formula: see text]), depending on the type of immersion solution and period, were analyzed using a repeated-measures analysis of variance (ANOVA) test. A web-based survey questionnaire was randomly distributed to 50 respondents for a visual analysis of the elastomeric chain discoloration. The relationship between the surveying score and [Formula: see text] value was analyzed using Spearman's correlation coefficient. The perceptibility and acceptability of elastomeric chain discoloration ([Formula: see text]) based on the type of immersion solutions and periods were analyzed using a regression model. RESULTS: Significant differences were observed in the discoloration of the elastomeric power chain depending on the immersion solution and period. The amount of discoloration was highest in curry, followed by coffee and wine (P < 0.05). The mean discoloration ([Formula: see text]) continued to increase over the entire immersion period. There was a significant correlation between visual scoring and discoloration ([Formula: see text]) over the entire period, especially in the early stages compared to the later stages (r = 0.918, P < 0.05). In 50% of the respondents, the predicted clinically unacceptable discoloration was between 4.46 and 9.98 and in 90% of the respondents, it was between 16.52 and 19.85. CONCLUSIONS: The amount of discoloration was the highest for curry, followed by coffee and wine, and continued to gradually increase during the observation period. Significant differences were found between the color measurements obtained and the visual assessment by observers. The observers varied in their tolerance for perceptibility and acceptability for elastomeric chain discoloration based on the type of dietary media.

Relationship Between Korean Adolescents' Dependence on Smartphones, Peer Relationships, and Life Satisfaction.

Background: In recent years, the penetration rate of smartphones among Korean teenagers has increased, making it critical to clarify the influence of these devices on adolescents' lives. Objective: This study investigated the effects of smartphone dependence on peer relationships and life satisfaction among Korean adolescents. Methods: Using the middle school panel of the Korean Children and Youth Panel Survey (KCYPS), longitudinal data of 2,250 participants (53.4% boys) at Grade 1 (M age = 14.01, SD = 0.03) in 2018, Grade 2 in 2019, and Grade 3 in 2020 were analyzed to examine the causal relationships between smartphone dependence, peer relationships, and life satisfaction. Results: This study found that smartphone dependence had a longitudinal effect on negative peer relationships. Negative peer relationships had a longitudinal negative effect on early adolescents' life satisfaction. Finally, negative peer relationships in early adolescents longitudinally mediated the relationship between smartphone dependence and life satisfaction. Conclusions: This study showed that early adolescents' dependence on smartphones negatively affects their social relationships and, in turn, negative relationships with peers hindered life satisfaction, suggesting that adolescents' smartphone use should be guided and, when necessary, receive assistance to develop control of their smartphone use.

Development pathways from abusive parenting to delinquency: the mediating role of depression and aggression.

This study investigated the long-term relationship between abusive parenting and adolescent mental health, and the path to delinquent behavior. Longitudinal data from 5th through 7th graders from the Korean Children and Youth Panel Survey (KCYPS) were analyzed to examine if abusive parenting was a predictor of early adolescent delinquency behavior, via aggression and depression as mediating factors. The results were as follows. First, parental abuse (both emotional and physical) was found to have significant effects on children's psychosocial factors (aggression and depression), while parental neglect (both emotional and physical) had significant effects on depression alone and not on aggression. Second, aggression exerted significant effects on both violent and non-violent delinquent behaviors, while depression had a significant effect on only non-violent delinquent behaviors. Third, children's psychosocial factors (aggression and depression) played significant mediating roles between earlier abusive parenting and delinquent behaviors. Fourth, for children living in a family with their grandparents, paths from abusive parenting, psychosocial adaptation, and later delinquent behaviors were not significant, implying that living with grandparents played a protective factor in these relationships.