system
Given the following post, respond as if you're commenting on Reddit:
human
How does your body push out foreign objects lodged under skin or in muscle?

I have a small piece of glass stuck under my skin in my finger, it’s been there for 10 years with no sign of movement. Then again when I had a prosthetic tooth put in, the dentist used synthetic bone graft. Months later it still felt like granules of bone working its way through the surrounding gum and out - first a bump on the gum the the piece of bone would break surface and pop out. How does your body know what is the shortest path out? What mechanism is used to push it out?
gpt
We don't necessarily push out all foreign objects. If an object gets particularly deep, scar tissue may form around the object and it will need to be removed manually. However, humans naturally shed the outer layer of our skin every few weeks, and new cells replace the old layer from the inside out, which will push objects lodged somewhat close to the surface of the skin to the outside.