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Aim of the study In the field of digital dentistry, Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) systems have changed the fabrication of prosthetic restorations by fulfilling both the aesthetic requirements and mechanical performance. This study aims to highlight, by conducting a chromatic evaluation of zirconium oxide when altering the sintering parameters Materials and methods Four groups of zirconium oxide each group formed by 5 copings were made through milling and Exocad digital design software. The design was completed and the files were processed with the Zeno 4030 M1 milling machine (I-MES Wieland). Following milling, the copings were sintered in HTS MIHM-VOGT furnace at a maximum sintering temperature of 1650°C and heating rates of 30°C/min or a rapid rate of 90°C/min. Controlled cooling prevented rapid temperature decrease, thereby minimizing internal stress. Modifications of time and temperature parameters were applied to groups 2, 3, and 4. Chromatic analysis of the specimens was registered with the Vita Easy Shade spectrophotometer. Results It was found that adjustments in sintering temperature and timing are significantly affecting the chromatic outcomes of the non-metallic zirconium structures. Temperature adjustments facilitate the coalescence of zirconium oxide particles and the formation of a robust structure, with changes in it affecting the optical behaviour of the structure. Deviations from the optimum temperature and sintering timing parameters negatively affect the shade. Conclusions In conclusion, milled and sintered zirconium oxide structures can achieve aesthetic excellence, provided by the sintering protocol when the temperatures and sintering furnaces are accurately calibrated. [ABSTRACT FROM AUTHOR]

Aim of the study This manuscript summarizes important ethical considerations relevant to embryo research. The aim of this study was to assess the opinion of three categories of doctors regarding the ethical and legislative implications of scientific research on human embryos. Material and methods To assess the opinion of doctors about the use of human embryos in research, from a related point of view, a questionnaire with 10 questions was made. Each question has three possible answers. Results The results were analyzed according to the age criterion, as follows:18-25 graduated doctors; 26-45 young doctors; 45-65 adult doctors with experience in the field. Conclusions Following the interpretation of the questionnaires, it can be concluded that, in view of the group of people considered, graduated doctors have more knowledge about the current legislation and ethical measures that accompany scientific studies on human biological material. Also, the third group of doctors with experience in the field tend to show the same knowledge as the first group. [ABSTRACT FROM AUTHOR]

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This article, published in the Romanian Journal of Oral Rehabilitation, examines the impact of various fabrication methods on the flexural strength of complete dentures. The study compares three different technologies: the classic press packing process and traditional polymerization, the injection technology and polymerization under constant pressure, and an original suction-injection process with polymerization under continuous pressure. The findings indicate that the suction-injection method with sustained pressure polymerization produces superior results compared to the other two methods. The study highlights the importance of selecting the appropriate fabrication technology to ensure the durability and strength of denture bases. [Extracted from the article]

This article explores the application of Optical Coherence Tomography (OCT) in evaluating the temperature variations during the sintering process of dental prosthetics. The study utilized OCT to examine metal-ceramic restorations at different sintering temperatures and generated cross-sectional images to identify defects and structural changes. The findings demonstrate that OCT can provide valuable insights into the impact of temperature deviations on ceramic microstructure, making it a useful tool for quality control in dental laboratories. The article suggests that integrating OCT into routine practices can offer a rapid, accurate, and non-destructive means of assessing sintering temperatures and detecting defects in dental ceramics. [Extracted from the article]

This article from the Romanian Journal of Oral Rehabilitation explores the role of ethics and medical legislation in retrospective experimental studies. The authors emphasize the importance of informed consent, which goes beyond obtaining a signature on a form, and discuss the current norms governing consent for retrospective research. They highlight the need for data anonymization and non-identifiability to protect individuals' identities. The article also emphasizes the significance of obtaining consent for retrospective human studies, while acknowledging exceptions in certain circumstances. Ethical review boards play a crucial role in evaluating the ethical implications of research studies. Overall, the article underscores the importance of ethical considerations, legal compliance, and respect for participants in retrospective studies. [Extracted from the article]

This article from the Romanian Journal of Oral Rehabilitation explores the impact of sintering temperatures on the assessment of dental ceramics. The study reveals that deviations in sintering temperatures can lead to changes in the density, mechanical properties, and color of the ceramic. The article also discusses the use of IPS Dentcisal powders and a spectrophotometer for shade matching and ceramic layering in dental restorations. However, the study found that despite these tools, the registered shades did not always align with the expected shade or shade guide. The findings highlight the importance of precise control over sintering temperatures and a comprehensive understanding of their effects on dental ceramics. [Extracted from the article]