I had root canal therapy last year but could not afford it so the office sent me home with out putting a crown on it and with a temporary filling to cover the hole. Two days ago that filling came out. I still can not afford the dentist . I was curious as to how dangerous my situation is or isn t. Also if there is any sort of filler or sealant I could purchase my self to fill the hole safely and to keep out any infection. I also need to know the best way to keep the open hole clean until I figure out what to do. Thank you.