I've always wondered, and this is a perfect example for this question, but with a large prosthetic like this, is it a solid latex piece, or does it end up being hollow.?
Most of the casting I've seen is just thin coating with latex and pulling it out to apply to the face. In this case, it a pretty big piece coming off the chin and if hollow, seems like it would flatten and get pushed in with pressure. However, if you fill it, you run the risk if there not being enough room for the person's chin inside of it.
Could you give some insight into this process, or am I over thinking it?