Choosing an appropriate prosthetic material for the superstructure of an implant-supported or tooth-implant supported fixed partial denture (FPD) is crucial for the success of the prostheses. The objective of this study was to examine the effect of prosthetic material type and tooth-to-implant support on stress distribution of FPDs using three-dimensional finite element analysis (3D FEA). Two FEA models were generated, distinguished by their support configurations: Model I representing an FPD supported by implants, and Model II depicting an FPD supported by both a tooth and an implant. Two different restorative materials, porcelain-fused-to-metal (PFM) and monolithic zirconia, were evaluated for stress distribution under axial and oblique loads of 300 N applied to the pontic. Under both axial and oblique loading conditions, the maximum von Mises stress values were observed to be higher in the implant-abutment complex of both zirconia implant-supported and tooth-implant-supported FPDs compared to PFM FPDs. In the case of axial loading, comparable stress values were found in the cortical bone for PFM (12.65 MPa) and zirconia implant-supported FPDs (12.71 MPa). The zirconia tooth-implant-supported FPD exhibited the highest stress values in the implant-abutment system.

Introduction. ALBO-HA (Vinca, Serbia) is new nanostructured calcium aluminate cement, synthesized as a potential alternative to mineral trioxide aggregate (MTA). The purpose of this study was to compare the periapical tissue response to new nanostructured calcium aluminate cement ALBO-HA with white MTA (MTA Angelus, Londrina, Brasil) as root-filling material into the root canal of sheep?s teeth. Material and methods. Sixteen mandibular incisors from two 24-month-old sheep were used. Root canals were prepared and filled with ALBO-HA (group 1) or MTA (group 2) (eight teeth per group in each sheep). After four weeks the animals were sacrificed, teeth with surrounding tissue removed, and histologically processed. The sections were analyzed for determination of scores of the following parameters: periapical inflammatory infiltrate, newly mineralized apically formed tissue, apical periodontal ligament space thickness and resorption of dentin, cementum and bone. Data were analyzed statistically (?=0.05) using Mann-Whitney U test. Results. Slight inflammatory infiltrate was observed in 75.0% and 62.5% of samples in the group 1 and group 2, respectively (p>0.05). Partial newly mineralized apically formed tissue was found in 75.0% of samples in the group 1, and 87.5% of samples in group 2 (p>0.05). No significant difference was noted for periodontal ligament space thickness (p>0.05). Resorption of dentin, cementum or bone was not observed. Conclusion. ALBO-HA and white MTA Angelus had a similar effect on inflammation, newly mineralized apical tissue formation and thickness of periodontal ligament space after root canal filling under the present experimental conditions.

Originally created for biological systems, molecular docking has proven to be versatile by being used to predict metal ion binding locations and affinities in materials. By using this novel approach, it was possible to estimate the binding energies of Ca2+, Sr2+, Mn2+, Cu2+, and Pr3+ ions for two different calcium sites in fluorapatite. The data obtained from the crystal structures of doped fluorapatites showed a good agreement with the docking research. The interpretation of docking results was made easier by combining results from DFT calculations with geometrical analysis of crystal structures of small molecules. Notably, this strategy is more favourable than previously used theoretical approaches due to computational efficiency and demonstrated reliability.