Decay can happen within months of having a
<span style = 'background-color: #dae8f4'>tooth</span> restored which means those crowns can fall out within months of placement depending on your oral hygiene. You can still get decay
under crowns, especially if you are not flossing and eating lots of carbs. It sounds like you need to work on your brushing and flossing. I would recommend an ultrasonic
toothbrush with a soft brush, sonicare is a good one with soft bristles.