I have a very deep tooth decay! I need your help!?

I'm very unfortunate to be 14 years old and have this deep decay in my Molar Tooth. Well, Poor dental care all my life. Partial blame to my parents but mainly myself. I'm ashamed of it. Its really horrible. Imagine your molar tooth with no center and able to put your finger in the middle. Yes my tooth is that much decayed. Anyways, I've finally decided to face the music and come out and tell my parents that I need dental care badly after realizing it could get infected. It seemed like this problem came along in 5th grade when I was about 11. And I've never had guts to tell my parents because of money issues. Well, As I said my molar is completely decayed basicly and I can put my pinky finger in the middle. I've done research and realize that root canal is out of the question because its too deep and the tooth won't be saved. Based off the description of my tooth, what will the dentist do to treat this? How much Pain? How long? Tough Procedure? etc. Please help.
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Let your dentist help you decide how to treat your tooth. Most dentists will do what they can to save the tooth root. Possibilities include root canal, a crown, filling, or extraction. Remember, painless dentistry is the norm these days. Root canals take a long time; extractions are usually very quick and relatively cheap but the downside is that you no longer have that tooth. Crowns are costly. If you lose the tooth, an implant is possible in an adult but not usually done in children (because the jaw is not yet fully grown). They are VERY expensive. All of these procedures can be done painlessly, usually with local anesthetic. For the future, get on a regular dental exam schedule. It's way easier (and cheaper) to get your teeth checked regularly a couple times a year (and get them cleaned too) than it is to suffer needlessly and then have to endure long, complicated, expensive restoration of rotten teeth.
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