My teeth are horrible....?

Ok I am 16 and I basically have horrible teeth. I haven't been to the dentist in over a year because I guess its not on the top of my family's priority list. Yeah I also really really need braces but I have only been to the orthodontist once and that was 3 years ago. I also have a horrible time with brushing my teeth too, I am lucky if I brush them once a day but I have gone without brushing them for 2+ days before. This is beacuse brushing my teeth makes me cough and gag really bad... Ugh I feel horrible and I know that I what I am doing is terrible. Any suggestions how I can talk my parents into taking me to the dentist (we have dental insurance) or how I can talk them into how important braces are or with brushing my teeth in general?? I have already talked to my parents and I have even printed them off articles but they are just like yeah ok eventaually we will get to it...
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owch they look painful, i had a tooth sticking up in the middle of my mouth and i thought that was bad before they removed it. My advice would be to talk to them again, just tell them how much it means to you, and mention that once you have been to the dentist and orthodontist and they have signed the papers they don't have to come with you any more (once you get the appointment for the braces and they have signed everything there's nothing that they need to do) Tell them that it ill take about a hour of their time and then you will be happy. (i didn't go to the orthodontist for about 6 years as first time i went they told me i couldn't be treated as i had too many baby teeth left) just keep on at them until they give in and tell them that it is impossible to brush them as they are (i know how you feel cause i found it hard to brush before i got my braces) With the coughing and gagging is it because you have to push the tooth brush in too far (if so i can't help that only a dentist can) or is it because the toothpaste if horrible and gets down your throat (if that's the case just ask your parents if you can try a different brand, even if it is just for you to use)
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