Flexural Strength of 3D-Printing Resin Materials for Provisional Fixed Dental Prostheses.

The clinical application of 3D-printed provisional restorations is increasing due to expansion of intraoral scanners, easy dental computer-aided design (CAD) software, and improved 3D printing speed. This study compared flexural strength of 3D-printed three-unit fixed dental prostheses with that of conventionally fabricated and milled restorations. A metal jig of two abutments and pontic space and an indenter for flexural strength measurement were fabricated. A three-unit fixed dental prosthesis was designed and manufactured using three additive manufacturing technologies, with subtractive manufacturing and a conventional method as controls. Digital light processing (DLP) group specimens were prepared from a polymethyl methacrylate (PMMA)-based resin and printed with a DLP printer. Stereolithography (SLA) group specimens were prepared from PMMA-based resin and printed with an SLA printer, and fused deposition modeling (FDM) group specimens were from a polylactic acid-based resin and printed with an FDM printer. Flexural strength was investigated using a universal testing machine, and the results were statistically analyzed. DLP and SLA groups had significantly higher flexural strength than the conventional group (p < 0.001). No significant difference was observed in flexural strength between DLP and SLA groups. The FDM group showed only dents but no fracture. The results of this study suggest that provisional restorations fabricated by DLP and SLA technologies provide adequate flexural strength for dental use.

Economic Burden and Disability-Adjusted Life Years (DALYs) of Attention Deficit/Hyperactivity Disorder.

Objective: We investigated the economic burden and disability-adjusted life years (DALYs) for attention deficit/hyperactivity disorder (ADHD) in the Republic of Korea. Method: Using the National Health Insurance Service claims data for the population aged 19 years or younger, a prevalence-based approach was used to calculate the DALYs of ADHD. Direct medical costs, direct nonmedical costs, and indirect costs resulting from ADHD were estimated to calculate the economic burden of ADHD. Results: A total of 69,353 people in Korea were diagnosed with ADHD in 2012. The burden of ADHD as measured by the prevalence-based approach was 32,605 DALYs. The total economic burden of ADHD was US$47.55 million, which accounted for approximately 0.004% of Korean GDP (gross domestic product) in 2012. Conclusion: Our findings shed light on the considerable burden of ADHD, emphasizing the need for policies that can encourage ADHD treatment and enhance compliance.

Evaluating the Minimal Specimens From Endoscopic Ultrasound-Guided Fine-Needle Aspiration in Pancreatic Masses.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become one of the most useful diagnostic modalities for the diagnosis of pancreatic mass. The aim of this study was to investigate the role of analyzing the minimal specimens obtained by EUS-FNA for the diagnosis of solid masses of pancreas.This study consisted of retrospective and prospective analyses. The retrospective study was performed on 116 patients who underwent EUS-FNA of solid masses for cytological smear, histological analysis, and combined analysis including immunohistochemical (IHC) staining. In the prospective study, 79 patients were enrolled to evaluate the quality and accuracy of EUS-FNA histological analysis and feasibility of IHC staining.The final diagnoses of all patients included pancreatic cancer (n = 126), nonpancreatic cancer (n = 21), other neoplasm (n = 27), and benign lesions (n = 21). In our retrospective study, the combined analysis was more sensitive than cytological analysis alone (P < 0.01). The overall sensitivity of cytology, histology, and combined analysis was 69.8%, 67.2%, and 81.8%, respectively. In the prospective analysis, 64.2% of all punctures were helpful for determining the diagnosis and 40.7% provided sufficient tissue for IHC staining. Histological analysis was helpful for diagnosis in 74.7% of patients. IHC staining was necessary for a definite diagnosis in 11.4% of patients, especially in the cases of nonmalignant pancreatic mass.Histological analysis and IHC study of EUS-FNA specimens was useful for the accurate diagnosis of pancreatic and peripancreatic lesions. Combined analysis showed significantly higher sensitivity than cytology alone because IHC staining was helpful for a diagnosis in some patients.

Prognostic significance of ATM and cyclin B1 in pancreatic neuroendocrine tumor.

Ataxia telangiectasia mutated kinase (ATM) and cyclin B1 are involved in cell cycle control. The prognostic significance of both molecules has not yet been investigated in pancreatic neuroendocrine tumors. The aim of this study was to evaluate the clinical and prognostic significance of ATM and cyclin B1 in patients with pancreatic neuroendocrine tumors. A total of 107 pancreatic neuroendocrine tumor specimens that were surgically resected were immunohistochemically investigated using the tissue microarray technique. Clinicopathologic results and survival were evaluated retrospectively. High expression of ATM and cyclin B1 was related to well-differentiated endocrine tumors of the World Health Organization (WHO) classification, but not related to TNM stages. The high ATM expression group (ATM ≥ 4) had a significantly smaller tumor size, lower recurrence rate, more number of functioning tumor, and well differentiation of WHO classification. The high cyclin B1 expression group (cyclin B1 ≥ 5) was related to smaller tumor size, less vascular invasion, less recurrence rate, and less death rate. However, cyclin B1 was the only significant factor for survival following multivariate analysis (p = 0.008; OR, 0.54; 95 % CI, 0.35-0.85). The current results suggested that expression of ATM and cyclin B1 may be useful markers to identify patients with poor prognosis who may benefit from close follow-up and aggressive therapy in pancreatic neuroendocrine tumors.

A prospective comparison of liquid-based cytology and traditional smear cytology in pancreatic endoscopic ultrasound-guided fine needle aspiration.

OBJECTIVE: To compare results of liquid-based cytology (LBC) and the conventional smear method (SMEAR) when performing endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for lesions of suspected pancreatic malignancy without an on-site cytopathologist. STUDY DESIGN: Fifty-eight patients were prospectively enrolled between July and December 2009. Aspirates obtained from the first needle pass were randomized either to SMEAR or LBC. Another sample from the second needle pass was allocated to the other method. The rest of the aspirates from the third or later needle passes were used for SMEAR. Diagnostic accuracy was compared and related factors were pursued. RESULTS: Although both methods were 100% specific, LBC was inferior to SMEAR in terms of sensitivity, negative predictive value, and accuracy. However, LBC provided correct diagnoses in 2 out of 3 cases of false negatives for malignancy by SMEAR in which blood was highly contaminated. Although no factor was identified for LBC, low blood contamination and more than 3 needle passes were related with accurate diagnosis in SMEAR. CONCLUSION: LBC was less accurate than SMEAR when performing pancreatic EUS-FNA without an on-site cytopathologist. However, LBC might serve as a good complement to SMEAR if blood contamination is profound.