Assessment of metal artifacts in three-dimensional dental surface models derived by cone-beam computed tomography / 대한치과교정학회지

OBJECTIVE: The aim of this study was to assess artifacts induced by metallic restorations in three-dimensional (3D) dental surface models derived by cone-beam computed tomography (CBCT). METHODS: Fifteen specimens, each with four extracted human premolars and molars embedded in a plaster block, were scanned by CBCT before and after the cavitated second premolars were restored with dental amalgam. Five consecutive surface models of each specimen were created according to increasing restoration size: no restoration (control) and small occlusal, large occlusal, disto-occlusal, and mesio-occluso-distal restorations. After registering each restored model with the control model, maximum linear discrepancy, area, and intensity of the artifacts were measured and compared. RESULTS: Artifacts developed mostly on the buccal and lingual surfaces. They occurred not only on the second premolar but also on the first premolar and first molar. The parametric values increased significantly with increasing restoration size. CONCLUSIONS: Metallic restorations induce considerable artifacts in 3D dental surface models. Artifact reduction should be taken into consideration for a proper diagnosis and treatment planning when using 3D surface model derived by CBCT in dentofacial deformity patients.

Hemorrhagic fever with renal syndrome and coexisting hantavirus pulmonary syndrome

Hemorrhagic fever with renal syndrome (HFRS) is an acute viral disease with fever, hemorrhage and renal failure caused by hantavirus infection. Hantavirus induces HFRS or hantavirus pulmonary syndrome (HPS). HPS progression to a life-threatening pulmonary disease is found primarily in the USA and very rarely in South Korea. Here, we report a case of HFRS and coexisting HPS.

A Case of Guide Wire Fracture With Remnant Filaments in the Left Anterior Descending Coronary Artery and Aorta

Guide wire fractures during percutaneous coronary intervention (PCI) are very rare, but when they do occur they may lead to life-threatening complications, such as embolization, thrombus formation and perforation. In cases when percutaneous retrieval has failed, surgical extraction of the remnant fragments is recommended. We present a case of remnant guide wire filaments that remained in place without complications, over a one-year clinical follow up period.

An Association of ADHD and Their Risk Factors in Pregnancy, Delivery, Perinatal Stage / 신경정신의학

OBJECTIVE: Many researchers reported that obstetrical complications during late pregnancy or delivery may be related to major psychiatric illnesses, especially schizophrenia. We hypothesized that obstetrical complications are among the most important factors which precipitate onset of attentiondeficit hyperactivity disorder. We studied retrospectively obstetrical complications of the Attention deficit-hyperactivity disorder(ADHD) patients who were diagnosed and treated at the outpatient and inpatient clinics of Ajou University Hospital. METHOD: The subjects were composed of 94 ADHD patients who were diagnosed by DSM-IV and 65 normal subjects. ADHD patients were divided into two groups; the familial group (n=27) consisted of those who have a family history of ADHD, and the non-familial group(n=65) consisted of those without a family history of ADHD. The authors examined gestational age, birth weight, type of delivery, and type of obstetrical complications. Obstetrical complications were divided into maternal, intrapartal and neonatal factors. RESULTS: 1) Non-familial ADHD patients have significantly higher NSVD(normal spont-aneous vaginal delivery) than normal controls. 2) Familial ADHD patients have significantly higher intrapartal obstetrical complications than normal controls. 3) ADHD patients have no significantly higher maternal and neonatal complications than normal controls. CONCLUSION: This study suggests that obstetrical complications are related to the onset of ADHD, possibly when combined with genetic predispositions.