Toenail Fungus

Good evening. I am writing to you to get your opinion regarding a problem I am encountering. I have a fungus on my big toe and the doctor told me to take Daktarin tincture. What I did. However after 6 months I don't see any results. Not even minimal.

My question is: how do I know if the nail bed is affected by fungus? (And therefore switch to oral treatment with medication?)

I had managed (before treating with the dye) to detach the nail thinking that it would grow back clean. It grew back but still in a state of fungus. In my opinion the bed is reached.

Thank you in advance for your answers.