Purpose: The scanning of plaster models for three-dimensional (3D) construction requires their rigid fixation in the intercuspal position. Factors such as installation, motion, and scanning procedures influenced the accuracy of this method, which ultimately influence the results. Therefore, the present study attempted to provide an optimal and accurate method with less complex procedures and a more accessible equipment for determining the intercuspal relation in the 3D occlusal construction of dental models. Methods: A pair of plastic mounting plates that could be directly attached to a mechanical articulator was designed and 3D printed. Nine axial hemispherical concaves were introduced on the axial surface of each plate. The rigidly fixed maxillary and mandibular dental models were scanned directly. The distances D_R between nine pairs of concaves on both mounting plates adhered to the maxillary and mandibular sections of the articulator were measured using the three-coordinate measuring machine Faro Edge as the reference. The present study comprised seven test groups varying in number and location. Assessing the reference points from each of the seven groups performed the 3D construction. The Geomagic Studio software was used to construct the concaves of digital casts, and the distances D_M between the pairs of concaves were measured as test values. Variable differences between D_R and D_M were analyzed. Results: An optimum distribution scheme was obtained for reference point registration by quantitatively evaluating accuracy levels of the 3D constructions of different reference point distribution patterns. This scheme can serve as a reference for related studies and dental clinic operations. Conclusions: Three-dimensional construction of the intercuspal relation during scanning of the maxillary and mandibular models with an accuracy of 0.046 mm ± 0.009 mm can be achieved using the improved design of mounting plates.

Background: Osteoporosis is a global health problem that significantly decreases patients’ quality of life and causes tremendous medical burdens. Therefore, exploring effective targeting strategies for osteoporosis treatment is crucial. Previous studies have indicated that pleiotrophin (PTN) was a secretory factor involved in several biological processes, such as angiogenesis, neural development, and abnormal osteogenic functions in osteoporosis. However, the roles of PTN in osteogenics and the mechanisms remain unclear. Methods: In this study, we explored the effects and mechanisms of PTN in regulating osteogenic functions using real-time quantitative PCR, immunofluorescence, ALP detection, a TUNEL assay, RNA sequencing, and phosphorylation quantitative proteomics. Fracture-healing experiments in osteoporosis rats were also conducted to evaluate the osteogenic functions of PTN in vivo. Results: We found that PTN significantly inhibited apoptosis and promoted the osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs). Further experiments showed that PTN regulated the biological functions of rBMSCs by promoting antioxidant functions and reducing cellular reactive oxygen species (ROS), thereby protecting rBMSCs from accumulated ROS. Additionally, we found that PTN binds to the PTPRZ1 receptor, inducing intracellular PLCG1 phosphorylation and NCOA3 nuclear translocation, which regulate the downstream antioxidant functions of rBMSCs. Additionally, we verified that PTN effectively promoted fracture healing in osteoporotic animals. Conclusions: This study elucidates the mechanisms by which PTN promotes osteogenesis and verifies this effect in vivo, offering an effective target for osteoporosis treatment.