At first, you'll need to adjust your new dentures to ensure that they fit snugly. But within a few weeks, you should be able to use your dentures comfortably. But over time, as your jawbone changes and your dentures age, you'll need to repair or adjust them to ensure they do their job properly. Otherwise, they could damage your oral tissues and change your facial appearance. The following are some of the common signs that you need denture repairs.