(Question) Please recommend a good ultra-fine toothbrush.

I have worn down teeth in the lower center, so I've been getting regular checkups. They say if they become worn down, they could need root canal treatment. So, I'm continuing to maintain them, and because of the wear, I use an ultra-fine-bristle toothbrush, but I'd like to try something different. I use an ultra-fine-bristle toothbrush, and I'd like some recommendations.