I have a missing tooth. Do I need a dental implant?

I had a tooth where a root canal was done. It was infected and had it removed. Do I need to have a dental implant? I would rather not because 1) I don't want another infection set in and then have to take the implant out.. 2) don't care much about cosmetics...tooth is a molar in the back 18? 3) My grandfather died of mouth cancer and I rather not do anything in my mouth... 4) I never had my teeth aligned and they're already crooked anyway... So what could happen without an implant? What is your advice? Thanks!
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The tooth above #18 (which is #15) may come down after a few years since there is nothing for it to bite against. But if you say that your teeth are crooked, then maybe not. Everyone has a different bite, so you may be ok. Oral cancer is not something you get from having dental treatment done. It is caused by smoking and or chewing tobacco. Also, infections with implants are EXTREMELY rare. Especially when they are done by a specialist, such as a qualified periodontist or oral surgeon. In our office, we refer our patients to a periodontist who is also an instructor at USC Dental School for the surgical placement of the actual implant. There is a healing time of about 6 months. After that, we place the crown on top of the implant. In 20 yrs of doing this, we have never had a case fail or had one with an infection.
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