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Purpose: Using a three-dimensional finite element method (3D-FEM), we compared the stress patterns and displacement on the implants, bone tissues, and prostheses in end-to-end implant-supported and cantilever implant bridges in the maxillary incisal region. Methods: Using a 3D-FEM, a model was constructed of the implant by rotating and adding threads according to the ITI Dental Implant System aesthetic requirements. The implant, prosthesis, and maxillary bone were assembled to form three different implant-supported bridges at different implant sites. Next, a 100-N load was applied at 0°, 30°, and 60°, and the stress values, displacements, and stress distribution were compared. Results: The stress distribution and displacement of the three models were similar in all three angles. In all three models, under axial loading, the stresses were majorly concentrated in the cortical bone around the implant neck and the apex; whereas the rest remaining stress was small and evenly distributed. Under oblique loading, the stresses were majorly concentrated in the cortical bone around the implant neck, and the stress value in the neck was greater than that in the apex. The cantilever implant bridge model produces I-type leverage action and its stress (implant 30°: 83.5 ± 6.9 Mpa or 133.8 ± 10.3 MPa vs. 65.1 ± 8.5Mpa; 60°: 115.1 ± 2.6 MPa or 141.0 ± 9.7 MPa vs. 98.1 ± 6.8 MPa. Cortical bone 30°: 48.6 ± 9.5 Mpa or 67.8 ± 5.9 MPa vs. 41.6 ± 9.8Mpa and 60°: 67.3 ± 6.3 MPa or 68.9 ± 10.2 MPa vs. 61.7 ± 6.4 MPa) and displacement (30°: 132.0 ± 13.2 μm or 169.0 ± 18.5 μm vs. 128 ± 7 μm and 60°: 168.0 ± 5.6 μm or 172.0 ± 19.2 μm vs. 167.0 ± 9.0 μm) are greater than those of the end-to-end implant-supported bridge model (P< 0.05). Conclusion: End-to-end implant-supported bridges have more uniform stress distribution and less displacement than single-implant cantilever beam bridges. End-to-end implant-supported bridges are ideal for replacing four consecutive missing incisors in the maxillary incisor region.

Purpose: The application of massive open online courses (MOOCs) helps integrate sustainable development goals (SDGs) into architectural curricula. The essence of MOOC development is building an education platform that promotes the sharing and continuing of global education resources. Design/methodology/approach: This study establishes a four-dimensional evaluation model based on the four characteristics of MOOCs. The quadrilateral area evaluation method is used to create an evaluation radar chart to comprehensively evaluate satisfaction and demand in the traditional teaching model of architectural technology. This study discusses whether the curriculum is suitable for the development of MOOCs and how to optimize the sustainable pedagogical mode according to its characteristics to meet future teaching needs and realize the sustainable development of education. Findings: Satisfaction evaluation found that current education is not open enough from the students' perspective; therefore, MOOCs enhance students' participation and significantly reduce future learning costs. Through demand evaluation, it was found that both teachers and students believed that the lack of direct and effective communication between them and the difficulty in ensuring the learning effect were problems that must be addressed in MOOCs. Originality/value: This study focused on the sustainability of MOOCs in curriculum development. It emphasizes the combination of MOOCs' teaching modes and the course itself and provides specific guidance and suggestions for improving the course. It uses an evaluation method for objective analysis and visualization.