Dental inlays can last for many years, sometimes even decades. Their longevity largely depends on how well you maintain your oral hygiene, your diet, and several other factors. The health of the tooth receiving the inlay also plays a significant role in how long the restoration will stay intact. If the tooth continues to decay and the inlay comes loose or falls out, the tooth will require further dental treatment. Additionally, orthodontic issues that put extra pressure on the restored tooth may cause the inlay to fail sooner than expected.