Gum and blacking teeth because of injury

Now, My 4 upper front teeth are becoming black from sides and my gum start loosing. i worried about prevent loosing them. I am 23 years old. from start my teeth was good and properly arranged in my school age i did not clean my teeth regularly in start. they become yellow. After that i start cleaning them on daily basis they become white again. 7 years before in college suddenly my 2 of below front teeth become injured by hurting a notice board corner. My teeth become imbalance those 2 teeth moved back upper teeth start touching lower gums. There was so pain. There was serious pain in my gums after injury. brushing become so pain full for me. after some time pain become slow but my teeth become very bad because of in regularity of cleaning. slowly slowly teeth are becoming dis balanced. i consult a dentist after 1.5 year he said that those moved teeth are now fixed. my family was not agree to show me to dentist because of money and according to their opinion this was a small injury it will cure by passing of time. dentist said that My teeth are in very bad condition from inside and roots are very weak near loosing them because of not brushing properly and when i brush them they will be clean. After that i brush 2 times in a day till now then how can it possible. i consult an other dentist he said moved teeth are in good condition upper front teeth are not good i will cure them. when he started to do i asked he said i am going to move out upper teeth i cannot under stand the reason. after this i never go to dentist. Because of my habit now my teeth start whitening again from some years but not completed yet. some part is very nice and some part is yellow front teeth are some how black and gum is still loosing. Can i do some thing. now you are my hope. can i trust on you? regards