To have option to have teeth less white

I’m working with lo-res b&w photos, 1940’s vintage. I find that upscaling can result in faces with unnatural teeth - so white that the result is like a toothpaste commercial (I’m using a blend with 40% processed, 60% original). Hope there will be a way to soften this effect while keeping good results e.g. excellent recovery of clothing & fabric.

Blend is necessary to avoid obvious ‘cutout’ effect separating foreground from background.