PURPOSE: To analyze the stress distribution of the implant and its supporting structures through 3D finite elements analysis for implants with different hexagon heights and to make the assessment of the mechanical stability and the effect of the elements. MATERIALS AND METHODS: Infinite elements modeling with CAD data was designed. The modeling was done as follows; an external connection type Phi 4.0 mm x11.5 mm Osste(R) USII (Osstem Co., Pusan, Korea) implant system was used, the implant was planted in the mandibular first molar region with appropriate prosthetic restoration, the hexagon (implant fixture's external connection) height of 0.0, 0.7, 1.2, and 1.5 mm were applied. ABAQUS 6.4 (ABAQUS, Inc., Providence, USA) was used to calculate the stress value. The force distribution via color distribution on each experimental group's implant fixture and titanium screw was studied based on the equivalent stress (von Mises stress). The maximum stress level of each element (crown, implant screw, implant fixture, cortical bone and cancellous bone) was compared. RESULTS: The hexagonal height of the implant with external connection had an influence on the stress distribution of the fixture, screw and upper prosthesis and the surrounding supporting bone. As the hexagon height increased, the stress was well distributed and there was a decrease in the maximum stress value. If the height of the hexagon reached over 1.2 mm, there was no significant influence on the stress distribution. CONCLUSION: For implants with external connections, a hexagon is vital for stress distribution. As the height of the hexagon increased, the more effective stress distribution was observed.
Dental Implants ; Molar ; Plants ; Prostheses and Implants ; Titanium

Acute myocardial infarction is one of the main causes of unusual death. However, diagnosing acute myocardial infarction based on post-mortem examination may be difficult; notably, it cannot be diagnosed based on postmortem inspection. In this study, we aimed to investigate the usefulness of cardiac marker analysis in the diagnosis of acute myocardial infarction and to review the possibility of its application in post-mortem inspections. This study included 69 autopsy cases, including 29 cases in which the post-mortem interval was ≤24 hours, performed at the National Forensic Service Seoul Institute from July to November 2018. Tests for three cardiac markers (myoglobin, creatinine kinase-MB, and cardiac troponin I) were performed in each case using portable equipment, Triage Meter. The reliability of the equipment enzyme levels according to cause of death, and factors affecting the postmortem test results were analyzed. Cardiac marker concentrations were not significantly different between the heart disease and other disease groups, and Triage Meter was not found to be suitable for postmortem examination. Therefore, we can conclude that using cardiac marker analysis in the diagnosis of acute myocardial infarction using portable equipment at the scene of postmortem inspection is inappropriate.

Acute myocardial infarction is one of the most common causes of unexpected deaths, but there are limitations to its diagnosis in postmortem inspection. In this study, we aimed to investigate the usefulness of cardiac marker analysis for the diagnosis of acute myocardial infarction in postmortem inspection. This study was conducted on 30 postmortem inspection cases conducted by the National Forensic Service from 2016 to 2018. Tests for three myocardial enzymes (myoglobin, creatinine kinase-MB, and cardiac troponin I) were performed in each case, and the relationships between enzyme levels, cause of death, and factors affecting the postmortem tests were analyzed. Cardiac enzyme concentrations were not significantly different between the heart disease group and other disease groups, and the false-positive rate was increased due to postmortem changes. Therefore, we can conclude that it is not appropriate to use cardiac enzyme analysis for the diagnosis of acute myocardial infarction in postmortem inspection.
Cause of Death ; Creatinine ; Diagnosis ; Heart Diseases ; Myocardial Infarction ; Postmortem Changes ; Troponin ; Troponin I

Acute myocardial infarction is one of the most common causes of unexpected deaths, but there are limitations to its diagnosis in postmortem inspection. In this study, we aimed to investigate the usefulness of cardiac marker analysis for the diagnosis of acute myocardial infarction in postmortem inspection. This study was conducted on 30 postmortem inspection cases conducted by the National Forensic Service from 2016 to 2018. Tests for three myocardial enzymes (myoglobin, creatinine kinase-MB, and cardiac troponin I) were performed in each case, and the relationships between enzyme levels, cause of death, and factors affecting the postmortem tests were analyzed. Cardiac enzyme concentrations were not significantly different between the heart disease group and other disease groups, and the false-positive rate was increased due to postmortem changes. Therefore, we can conclude that it is not appropriate to use cardiac enzyme analysis for the diagnosis of acute myocardial infarction in postmortem inspection.