Comparative analysis of the strength of temporary bridge prostheses with different types of reinforcement framework under immediate load on dental implants

Relevance. Temporary plastic bridge prostheses supported by dental implants, used in immediate loading protocols, often fail due to fracture of the internal reinforcing framework. The optimal configuration of a 1 mm diameter titanium wire framework remains unclear. Objective — to perform a comparative analysis of four titanium wire framework configurations under vertical and combined loads (up to 800 N) with safety factor calculation and selection of the optimal topology. Materials and methods. Four models of a temporary bridge prosthesis (12 artificial teeth, 4 implants) were analyzed using the finite element method in ANSYS 22.5. Configuration №1 — single lingual wire; №2 — single buccal wire; №3 — two alternating (lingual/buccal) bent wires; №4 — two alternating straight welded fragments. Pre-tension of screw joints (548 N and 278 N) was simulated. Loading scenarios: vertical 250 N and 500 N on incisors; combined 500 N and 800 N on occlusal surfaces. Results. Under combined 500 N load, configuration №2 showed critical stresses (956.28 MPa, safety factor 0.87). Under 800 N load, all configurations had safety factor <1.0 (0.87—0.97). Configuration №4 (alternating welded fragments) demonstrated the lowest peak stress (856.20 MPa), lowest mean stress (125.53 MPa), lowest standard deviation (125.64 MPa), and lowest interquartile range (126.88 MPa). Increasing the wire diameter to 1.25 mm yields a predicted safety factor of 1.51. Conclusion. The spatial alternating welded framework (configuration №4) provides superior stress distribution. A 1 mm diameter is insufficient for 800 N loads. Increasing the diameter to 1.25—1.3 mm is recommended. The single buccal wire configuration is contraindicated.