The patient was a 78-year-old man who presented with dyspnea and decreased SpO₂ in the sitting and standing positions. Transthoracic echocardiography revealed a patent foramen ovale (PFO), and a microbubble test showed Grade 1 in the supine position and Grade 4 in the sitting position, suggesting an increase in shunt volume when seated. Chest CT revealed age-related kyphosis and right atrial compression by the ascending aorta. The patient was diagnosed with platypnea-orthodeoxia syndrome (POS) due to PFO, and a PFO closure was performed using minimally invasive cardiac surgery (MICS). The postoperative course was favorable, and the patient was discharged on the 20th postoperative day. Although percutaneous device closure is generally performed for PFO closure, MICS was useful in this case due to the anatomical unsuitability caused by an atrial septal aneurysm.

PURPOSE: The purpose of this study was to evaluate the efficacy of two different metal conditioners for non-precious metal alloys for the bonding of porcelain to a cobalt-chromium (Co-Cr) alloy. MATERIALS AND METHODS: Disk-shaped specimens (2.5x10.0 mm) were cast with Co-Cr alloy and used as adherend materials. The bonding surfaces were polished with a 600-grid silicon carbide paper and airborne-particle abraded using 110 microm alumina particles. Bonding specimens were fabricated by applying and firing either of the metal conditioners on the airborne-particle abraded surface, followed by firing porcelain into 5 mm in diameter and 3 mm in height. Specimens without metal conditioner were also fabricated. Shear bond strength for each group (n=8) were measured and compared (alpha=.05). Sectional view of bonding interface was observed by SEM. EDS analysis was performed to determine the chemical elements of metal conditioners and to determine the failure modes after shear test. RESULTS: There were significant differences among three groups, and two metal conditioner-applied groups showed significantly higher values compared to the non-metal conditioner group. The SEM observation of the sectional view at bonding interface revealed loose contact at porcelain-alloy surface for non-metal conditioner group, however, close contact at both alloy-metal conditioner and metal conditioner-porcelain interfaces for both metal conditioner-applied groups. All the specimens showed mixed failures. EDS analysis showed that one metal conditioner was Si-based material, and another was Ti-based material. Si-based metal conditioner showed higher bond strengths compared to the Ti-based metal conditioner, but exhibited more porous failure surface failure. CONCLUSION: Based on the results of this study, it can be stated that the application of metal conditioner is recommended for the bonding of porcelain to cobalt-chromium alloys.
Alloys* ; Aluminum Oxide ; Chromium Alloys ; Dental Porcelain* ; Fires ; Shear Strength ; Silicon