3D Surface Deviation Wear Analysis of Veneered PEEK Crowns and Its Correlation with Optical Digital Profilometry.

PURPOSE: To verify whether 3D surface deviation analysis software can detect the surface changes of composite veneered polyetheretherketone posterior crowns following wear simulation compared to optical digital profilometry. MATERIALS AND METHODS: Twenty dental crowns, fabricated from CAD-CAM polyetheretherketone (PEEK) and veneered with high impact polymer composite (HIPC), were subjected to wear test (50N, 5/55°C; 120,000 chewing cycles). Optical digital profilometry and 3D surface deviation using Geomagic design X software was used before and after the wear test to measure volumetric wear loss (mm3 ). The data were statistically analyzed with Wilcoxon signed-rank test to compare the two methodologies. The significance level was set at p ≤ 0.05. RESULTS: There was no statistically significant difference between the two assessment methods (p-value = 0.075, Effect size = 0.854). Regarding the optical digital profilometry analysis, HIPC veneered PEEK crowns showed 0.01686 (0.018-0.02155) mm3 as a median volumetric wear loss value. While the crowns analyzed by 3D surface deviation showed -0.0398 (-0.0913 to -0.0042) mm3 as a median volumetric loss value (p-value = 0.075, Effect size = 0.854). In addition, there was no statistically significant correlation between wear measurements by optical digital profilometry and 3D surface deviation analyses (ρ = -0.177, p-value = 0.685). CONCLUSIONS: There was no significant difference or correlation between optical digital profilometry and 3D surface deviation analyses for volumetric wear loss of veneered PEEK crowns.

A Young Male Presenting With Chest Pain, Elevated Troponin Levels, and a Clinical Dilemma: A Case Report.

Chest pain is a common presentation that may represent a wide variety of underlying etiologies ranging from mild self-limiting conditions to immediately life-threatening emergencies. The combination of "cardiac-sounding chest pain" and elevated troponin levels would raise suspicion of an acute ischemic event. An acute coronary syndrome is a diagnosis that may be straightforward; however, oftentimes, patients with elevated troponin levels and chest pain may bring about a state of diagnostic uncertainty. Alternative diagnoses to consider would be inflammatory or infectious conditions of the myocardium and pericardium. We present the case of a young gentleman in his twenties who presents with cardiac chest pain, elevated troponin, and non-specific changes on his electrocardiogram who was treated for an alternative cause of elevated troponin and chest pain, myopericarditis. We present the case of a 24-year-old male who presented with a six-hour history of debilitating retrosternal chest pain. Initial workup showed a Troponin I level greater than 15,000 ng/L, D-Dimer greater than 1,000 mcg/L with no overt ischemic features on electrocardiogram. The patient had no high-risk features in his medical history & denied the use of recreational drugs. A formal same-day echocardiogram revealed normal biventricular systolic function and no evidence of regional wall motion abnormality (RWMA). He was eventually treated clinically for myopericarditis. A Cardiac MRI (CMR) imaging was done to confirm the diagnosis and rule out, most importantly, ischemic heart disease or any other underlying pathology. The main dilemma in this case was working out whether there was indeed peri-myocardial inflammation, or an acute coronary event (such as spontaneous coronary artery dissection) given his age and clinical history. Patients presenting with a very high troponin level, particularly in young patient cohorts, should raise suspicion of a myocardial or pericardial inflammatory process. In addition to a thorough history and in the absence of ischemic changes on the electrocardiogram, subtle findings such as PR segment depression may point to a diagnosis of pericardial inflammation. While urgent echocardiography is useful to quickly assess ventricular function and for RWMA, CMR imaging is the Gold Standard modality of investigation to provide detailed structural information of the heart.

Incremental lowering of low-density lipoprotein cholesterol with ezetimibe 20 mg vs 10 mg daily in patients receiving concomitant statin therapy.

BACKGROUND: Ezetimibe is typically administered at a dose of 10 mg daily, with few reports of use at other doses. We compared plasma concentrations of low-density lipoprotein (LDL) cholesterol and other lipid variables in patients with dyslipidemia who were receiving ezetimibe 10 mg and then 20 mg daily. METHODS: A retrospective chart review identified 27 patients who received ezetimibe 10 mg and then 20 mg daily at different times; 15 participants were receiving stable statin therapy and 12 were not receiving concomitant statins. Plasma concentrations of lipids, creatine kinase (CK), and aspartate transaminase (AST) were determined. Plasma concentrations of ezetimibe and ezetimibe glucuronide were measured in a second group of patients. RESULTS: Patients taking statins and ezetimibe 20 mg had further reductions in total and LDL cholesterol of 7.1% and 10.3%, respectively (both P < 0.05) than did those receiving the 10-mg dose. No difference between 20-mg and 10-mg dosing was seen among patients not receiving statins. Plasma concentrations of ezetimibe and its active metabolite were about 2-fold higher (P < 0.05) in patients taking ezetimibe 20 mg than in those receiving 10 mg daily. All patients tolerated ezetimibe 20 mg without side effects. CONCLUSIONS: Ezetimibe 20 mg daily reduced total and LDL cholesterol further in patients receiving statin therapy compared with 10 mg daily. Prospective studies are required to show whether the higher plasma levels of ezetimibe and its active metabolite in patients taking the 20-mg dose have any detrimental effects. Increasing the ezetimibe dose to 20 mg daily might be an interesting potential approach for patients who fail to reach lipid targets on ezetimibe 10 mg daily along with maximally tolerated doses of statin.