Are tear trough implants placed intra-orally safe? Is there a risk of nerve damage?

Good Afternoon! Great question. The infraorbital nerve is a big sensory nerve providing input to the cheek area as on the diagram. It's rather easy to identify from an intra-oral route as long as care is taken to elevate the tissues gently. The implants themselves often are crafted in such a way that they have a notch to fit around and not compress the nerve near its foramen. If going through the lower eyelid, it's a similar approach - just from the top-down instead. Hope that helps!