My sides of my nose have shrunken in, just behind the ball/tip of my nose. It has become worse over the last few years, and is obvious when I have photos taken. Is surgey required to correct this, or can some sort of "filling material" simply be injected to fill out the deflated area?
The deformity you are describing is known as a "pinched tip" . The problem is a lack of support for the nostril rim often due to weak cartilages. The weakness in the cartilage is most often due to previous surgery where some of the cartilage has been removed, but can occur by itself. The solution is to reinforce the strength of the cartilage and this is a surgical procedure often using cartilage from your nasal septum. Using a filler is unlikely to provide the support the skin needs and not achieve the result you are after.