Investigation of firing temperature variation in ovens for ceramic-fused-to-metal dental prostheses using swept source optical coherence tomography
| Autor: | Virgil-Florin Duma, Meda-Lavinia Negrutiu, Adrian Gh. Podoleanu, Adrian Bradu, Raluca Todor, Florin Topala, Cosmin Sinescu, Mihai Rominu |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
R857.O6
Fabrication Materials science medicine.diagnostic_test Alloy technology industry and agriculture RK Sintering 030206 dentistry engineering.material 01 natural sciences 010309 optics 03 medical and health sciences Granulation 0302 clinical medicine Optical coherence tomography visual_art 0103 physical sciences Thermal engineering medicine visual_art.visual_art_medium Substructure Ceramic Composite material |
| ISSN: | 1605-7422 |
| Popis: | One of the most common fabrication techniques for dental ceramics is sintering, a process of heating of the ceramic to ensure densification. This occurs by viscous flow when the firing temperature is reached. Acceptable restorations require the alloy and ceramic to be chemically, thermally, mechanically, and aesthetically compatible. Thermal and mechanical compatibility include a fusing temperature of ceramic that does not cause distortion of the metal substructure. Decalibration of ovens used for firing of the ceramic layers for metal ceramic dental prostheses leads to stress and cracks in the veneering material, and ultimately to the failure of the restoration. 25 metal ceramic prostheses were made for this study. They were divided in five groups, each sintered at a different temperature: a group at the temperature prescribed by the producer, two groups at lower and two groups at higher temperatures set in the ceramic oven. An established noninvasive biomedical imaging method, swept source (SS) optical coherence tomography (OCT) was employed, in order to evaluate the modifications induced when using temperatures different from those prescribed for firing the samples. A quantitative assessment of the probes is performed by en-face OCT images, taken at constant depths inside the samples. The differences in granulation, thus in reflectivity allow for extracting rules-of-thumb to evaluate fast, by using only the prostheses currently produced the current calibration of the ceramic oven. OCT imaging can allow quick identification of the oven decalibration, to avoid producing dental prostheses with defects. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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