Interproximal decay is decay that occurs between the teeth, where one tooth touches another. It most often begins to appear in early teen years and continues throughout adulthood. X-rays are necessary to detect early interproximal decay.
Brushing does little to prevent decay in between the teeth, and sealants cannot be placed to cover these surfaces. Limiting sugar and carbohydrate intake and using prescription strength fluoride toothpaste can help reduce the incidence of interproximal decay… But above all, flossing is the most effective way to keep these areas clean and decay free.