A high-noble Au–Pt–Ge porcelain-fused-to-metal (PFM) dental alloy without the known adverse metallic elements and with the addition of germanium (Ge) was produced as a more cost-effective alternative to other precious alloying metals, with investigations for determining the functionality and clinical use of this alloy. The thermomechanical, biocompatibility, durability, workability and economic characteristics of the produced dental alloy were investigated. These properties were investigated with in vitro biocompatibility testing on human gingival fibroblasts (HGFs); static immersion testing for metal ion release; DSC analysis; hardness, tensile testing, density and coefficient of thermal expansion (CTE) measurements; metallographic and SEM/EDX microstructure investigations; and finally with the production of a test PFM dental bridge. The results of the thermomechanical testing showed alloy properties suitable for dental restorations and clinical use, with somewhat lower mechanical properties, making the alloy not suitable for extensive multiunit fixed restorations. The microstructure investigations showed segregations of Ge in the homogeneous alloy matrix, which reduce the alloy’s mechanical properties. The produced PFM dental bridge showed excellent workability of the alloy in a dental laboratory setting, as well as a high standard of the final dental restoration. The ion release was negligible, well below any harmful quantities, while the cell viability examination showed significantly higher viability ratings on polished alloy samples as compared to as-cast samples. The results showed that a dental substructure in direct contact with oral tissue and fluids should be highly polished. The performed investigations showed that the produced PFM dental alloy is suitable for clinical use in producing high-quality dental restorations with high biocompatibility for patients prone to metal allergies.

Thermomechanical, biocompatibility, durability, workability and economic characteristics are the main criteria for development of dental alloys. In an attempt to provide a noble metal dental alloy without the known adverse metallic elements, a novel alloy was produced with the addition of Germanium (Ge), as a more cost-effective alternative to other precious alloying metals. The objective of this investigation was to analyse the thermomechanical and biocompatibility properties of a high noble Au-Pt-Ge porcelain-fused-to-metal (PFM) alloy. These properties were investigated with DSC analysis, hardness, density and coefficient of thermal expansion (CTE) measurements, as well as with metallographic and SEM/EDX microstructure investigations, with the production of a test PFM dental bridge, static immersion testing for metal ion release, and an in vitro primary biocompatibility testing on human gingival cells. The results of the thermomechanical testing showed alloy properties suitable for dental restorations and clinical use, with somewhat lower hardness, making the alloy not suitable for extensive multiunit fixed restorations. The microstructure investigations showed segregations of Ge in a homogeneous alloy matrix, which reduce the alloy’s mechanical properties. The produced PFM dental bridge shows excellent workability of the alloy in a dental laboratory setting, as well as a high standard of the final dental restoration. The ion release was negligible, well below any harmful quantities, while the cell viability examination showed significantly higher viability ratings on polished alloy samples as compared to as-cast samples. The results showed that a dental substructure in direct contact with oral tissue and fluids should be highly polished.

Introduction/Objective. Effective disinfection of the root canal system is essential for successful endodontic treatment. This study aimed to determine the most effective final irrigation protocol. Methods. This randomized clinical trial investigated the antimicrobial efficacy of three irrigation protocols in 30 patients with asymptomatic apical periodontitis in single-rooted teeth. The groups were: (1) 2.5% sodium hypochlorite (NaOCl) + 17% EDTA; (2) NaOCl + EDTA + 2% chlorhexidine (CHX); and (3) the same as Group 2 with sonic agitation (EndoActivator). Microbial samples were collected at three intervals and analyzed using end-point and real-time PCR targeting seven key endodontic pathogens. Results. Group 3 demonstrated the greatest bacterial reduction across all time points, with CHX-containing protocols significantly outperforming NaOCl + EDTA alone. Sonic activation further enhanced irrigant efficacy, notably reducing P. gingivalis. Despite improvements, complete bacterial eradication was not achieved, and E. faecalis and F. nucleatum remained persistent. Conclusion. While limitations in microbial sampling and profiling exist, the results underscore the importance of combining chemical agents and mechanical activation to manage complex root canal infections effectively.

Introduction/Objective. Traditional diagnostic methods for assessing pulp vitality are commonly used but lack precision and reliability, whereas recent advancements offer non-invasive alternatives, focusing on pulp tissue blood flow and oxygen saturation. This study was designed to evaluate and compare the reliability of all available clinical diagnostic methods for assessing pulpal status and to establish reference values in healthy young individuals. Methods. This cross-sectional observational study enrolled 25 voluntary participants (27.8 ? 5.2 years old), 150 upper front teeth. The participants were healthy individuals, non-smokers, teeth with a mature apex, no or minimal restorations, periodontally healthy, and radiographically visible pulp chambers. Various diagnostic tests were conducted, including electric, cold, and hot pulp testing, Laser Doppler flowmetry, and pulse oximetry (EPT, CPT, HPT, LDF, and PO); The reference values were established. Results. Statistically significant differences were observed among all tooth groups (central incisors, lateral incisors, and canines) for EPT, LDF, and PO. In contrast, CPT and HPT showed no statistically significant differences between the tooth groups. The mean values across all patients were as follows: EPT - 17.7 ? 5.4, PO - 80.6 ? 1.8%, and LDF - 4.6 ? 1.6 perfusion units. Correlation analysis showed no significant relationships between all tests. Conclusion. Modern diagnostic techniques show promise in offering more reliable results. Establishing reference values is essential for improving diagnostic accuracy. These values will not only enhance clinical decision-making but also serve as a foundation for future investigations.