U-Mamba2 is a novel neural network architecture for automatic segmentation of teeth and jaw structures from dental Cone-Beam Computed Tomography (CBCT) images. It integrates the Mamba2 state-space model into the U-Net architecture to enhance efficiency, and leverages interactive click prompts, self-supervised learning, and dental domain knowledge to improve performance. It won first place in the ToothFairy3 challenge.