Morning and evening for me, plus flossing at any time.
Pre Covid days when going out, I always cleaned them before going out too.
Occasionally I use salt water too, but that’s more on my tongue.
My teeth have never been white white, and certainly not strong teeth. Whereas my sisters teeth are white white and stronger, and she smokes 40+ fags a day.
Mum’s teeth were good teeth but weren’t white white and dad’s teeth he lost most of his after the war and went on to full dentures, which ended up in the glass every night.
My teeth have yellowed within the last 4yrs and I think it’s a combination of thin enamel, low calcium levels and smoking.
My sister’s are still white.
Genes suck sometimes