Critical-size defects in the lower jaw (mandible) represent a significant clinical challenge, necessitating the development of innovative treatment approaches. Electrical bone stimulation is a novel approach that has proved successful with more minor bone defects. Initial implant designs created in SFB 1270 ELAINE demonstrated considerable promise in terms of conceptual suitability yet also highlighted the necessity for further research. In line with the approach proposed by Kraus, electric field strengths between 5 and 70 V/m are considered beneficial. Furthermore, field strengths above 70 V/m be avoided, as they carry an inherent risk of overstimulation. In particular, the limited volume of beneficial stimulation of only about 50 % of the defect volume in applications with bipolar stimulation electrodes indicates a need for improvements in electrode design. The finite element simulations presented in this research demonstrate that when using dual-sided thin film electrodes as shown in Fig. 1, over 98 % of the defect volume can be stimulated beneficially, while only 0.6 % is overstimulated. This encouraging result can be further refined in optimisation studies, paving the way for well-prepared pilot in vivo validation studies in minipigs. The novel electrostimulation design of the treatment of critical-size bone defects in a large animal model is promising to advance the treatment of large mandible bone defects in humans in the near future.

This work is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – SFB 1270/2 – 299150580.