Impact of storage media and temperature on color stability of tooth-colored CAD/CAM materials for final restorations.

BACKGROUND: This in-vitro study examined the impact of storage solution, storage duration, and storage temperature on discoloration of three tooth-colored CAD/CAM materials for final restorations. METHODS: Specimens (N = 288; n = 96 per material) with a thickness of 1 ± 0.03 mm of the following CAD/CAM materials were fabricated: resin composite (Lava Ultimate, 3M), polymer-infiltrated ceramic (VITA Enamic, VITA Zahnfabrik), and leucite ceramic (IPS Empress CAD, Ivoclar Vivadent). After baseline measurement, specimens were stored in red wine, curry solution, cress solution, and distilled water at 37°C or 55°C. The discoloration was measured using a spectrophotometer (Lambda 35 Perkin Elmer, Perkin Elmer Inc.) after 1 and 7 days storage. Data were analyzed using four-way ANOVA followed by the Scheffé post-hoc test and partial eta squared (ηP²) test (p < 0.05). RESULTS: The highest influence on ∆E was exerted by storage duration (ηP² = 0.295, p < 0.001), followed by storage solution (ηP² = 0.171, p < 0.001), CAD/CAM material (ηP² = 0.049, p < 0.001), and storage temperature (ηP² = 0.033, p < 0.001). Specimens stored for 7 days in staining solutions showed more discoloration than those stored for just 1 day. Higher ∆E values were achieved for specimens stored in curry solution, followed by red wine, cress solution, and distilled water. Resin composite Lava Ultimate showed larger ∆E values compared with the resin hybrid ceramic VITA Enamic and leucite ceramic IPS Empress CAD. Specimens stored at 37°C showed significantly less discoloration than those stored at 55°C. CONCLUSIONS: The degree of coloration of the materials depends on food and temperature and was most pronounced with Lava Ultimate.

Imaging osteomyelitis with Tc-99m-labeled antigranulocyte antibody Fab' fragments.

PURPOSE The purpose of this study was to evaluate the diagnostic value of Tc-99m-labeled antigranulocyte antibody fragments in the diagnosis of osteomyelitis. MATERIALS AND METHODS Thirty immunoscintigrams were evaluated retrospectively with 740 MBq (20 mCi) Tc-99m-labeled antigranulocyte antibodies. The final diagnoses were confirmed by histology, magnetic resonance imaging, computed tomography, and clinical follow-up. RESULTS In the retrospective analysis, 20 of 30 patients (67%) demonstrated a true-positive result. Three of 30 patients (10%) had a false-positive result. A false-negative result was found in a diabetic patient with a perforating ulcer of the foot. Six of 30 patients had a true-negative result. A high sensitivity of 95%, a relatively high specificity of 67%, and a high diagnostic accuracy of 86% were present in this study. CONCLUSION Tc-99m labeled monoclonal antibody-Fab' fragments are suitable for the detection of osteomyelitis. Its clinical application is simple. Its use guarantees a reliable and accurate diagnostic result just 1 to 2 hours after injection, making a late scan unnecessary. Coxarthrosis or hyperostosis can lead to false-positive results. A perforating ulcer of the foot may result in a false-negative conclusion.