Dentures can last long with proper care. You can ask your dentist or you can follow these few tips for that extra push on them to persist.
Never let your dentures dry out. Either place them in a glass with denture cleanser soaking solution or just plain water. Avoid using hot water as it causes the dentures to warp.
Brush your dentures as you would your normal set of teeth to rid it of food and dental plaque, as well as prevent stain build-up.
It should already go without saying, but you should take care of your teeth as well. Add gargling with mouthwash and brushing your palate every morning to your daily routine, as doing both can help remove plaque.