Then again the vert is being pulled downward from the upper lip. Generally such a thing would be happening because of the weighting of the lower jaw. I don't think alyson has an upper jaw lol. I can't check, poser is tied up rendering.

The only reason it even occured to me is from seeing similar spiking occuring in conformers...

I'll have to bow out of this one. Not enough concise information, and not likely to be. If it's a morph problem it would require fix morphs and subtracting the baked open mouth as a morph from the lot. Probably beyond the scope of what OP would want to do.

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