ABSTRACT
This study evaluated release of the residual monomer and cytotoxicity after polymerization of three denture base resins (heat curing resin, self-curing resin, light curing resin by 3D printer). Three types of resin specimen according to the manufacturer’s guideline were fabricated: heat curing resin (Group H), self-curing resin (Group S), 3D Printed resin (Group L). Each group of specimen were stored in distilled water at 37 ℃ for 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks, and 8 weeks in order to measure the release of the residual monomer. Absorbance was measured at each storage time in the three groups. Cytotoxicity is measured by MTT test at each storage time in the three groups. For statistical analysis, one-way ANOVA with post-hoc tests of Dunnett T3 test and Scheffe test were carried out, where p values of less than 0.05 were considered as significant. Group H showed the lower absorbance than Group S and Group L. There was no statistically significant difference in the absorbance of Group S and Group L for 8 weeks, except for the one day. Group H and Group S showed no cytotoxicity, but Group L resulted in cytotoxicity. To conclude, light curing resin used in 3D printer revealed high cytotoxicity in this study. In order to apply the 3D printed denture base resin to clinical situation, it is necessary to develop a method to reduce the release of residual monomers.
ABSTRACT
PURPOSE: Predicted adult height (PAH) is often crucial to decision-making about treatment with human growth hormone (GH) or gonadotropin-releasing hormone agonist in children with short stature. This study compares final adult height (FAH) with different methods used to determine PAH and assesses the clinical utility and analytical validity of height prediction for children not treated with GH. METHODS: Clinical findings were retrospectively analyzed, and the heights of 44 children (22 males and 22 females) who visited our clinic between August 2006 and June 2017 and reached near final adult height (NFAH) were evaluated. Children treated with GH were excluded. We compared measured NFAH to PAH using the Bayley-Pinneau (BP), Tanner-Whitehouse Mark 2, and Roche-Wainer-Thissen (RWT) methods. RESULTS: Pearson correlation between all 3 prediction methods and NFAH showed high positive correlations in males and females (P < 0.05). The average difference between PAH and NFAH for the BP method (0.4±3.9 cm) was significantly lower than those for the RWT and TW 2 methods in females (P=0.000, analysis of variance). Furthermore, only PAH by the BP method in females was very close to measured NFAH (paired t-test). A Bland-Altman plot verified that 95% of the differences between the PAH and NFAH exist between limits of agreement (mean±1.96 standard deviation). CONCLUSIONS: The BP method is more useful to predict NFAH in females than other methods. Careful attention is still required when using such tools because PAH can be inaccurate. Therefore, a more accurate FAH prediction model for Korean children is needed.
Subject(s)
Adult , Child , Female , Humans , Male , Gonadotropin-Releasing Hormone , Human Growth Hormone , Methods , Retrospective StudiesABSTRACT
Menkes disease is a rare, neurodegenerative, copper metabolism disorder characterized by mutations in ATP7A gene. Clinical symptoms include epilepsy, growth delay, reduced muscle strength, skin hyperextension, hair deformation and urologic abnormalities. However, since these clinical symptoms occur 2–3 months after birth, early diagnosis of Menkes disease is very difficult for clinicians. We report here the case of a patient who initially presented urinary tract infection followed by neurologic symptoms of Menkes disease; he was accurately diagnosed via ATP7A genetic analysis and found to harbor a novel mutation. Although neurological symptoms are the primary diagnostic feature of Menkes disease, clinicians should take into account urinary abnormalities as well, which may be an important clue to the early diagnosis of these patients.