Makes mouths plastic and circular. I've been trying to get this one working since SDXL and I think I might have cracked it with Pony - at least decently enough to share. Works decently in combination with inflatable or latex LoRAs.

A weight of 1 for the LoRA and trigger "gaping mouth hole" seems to work well. Add in "COLOR lips" for better results and "ribbed inner mouth" to widen out the mouth.