Here's some further info on criteria for wisdom tooth extraction/surgery times/post operative pain/healing time/who should do the extractions that I provide my patients with everyday.
1st: criteria for removal, I break it down as simply as this, is the tooth fully errupted and in function with an opposing tooth, can the patient keep the tooth clean, is the periodontal condition around the wisdom tooth the same as around adjacent teeth. If any of these questions are answered "no" then I recommend extraction.
As for the comment that errupting wisdom teeth promote anterior crowding, thats one of the biggest misconceptions in dentistry. The medial force that the wisdom tooth places on the errupted 2nd molars isn't anywhere near enough force to move and tip the roots of the 7 teeth that are infront of it. Ask an orthodontist sometime about it. True though that over time, without retention, the errupted dentition will as a whole move medially for most folks, and thats what will cause alot of post orthodontically treated folks to have anterior crowding when they reach their late 20's/30's.
Surgery times: For an errupted wisdom tooth, any practictioner who is comfortable with extractions should take no more than 3 to 4 minutes a tooth. If the tooth is impacted requiring elevation of a flap and either removal of bone and/or sectioning of the tooth, it can take upto 30 minutes per tooth depending on the tooths angulation, bone density, sinus and inferior alvelor nerve proximity. Healing time for most folks will take on average 5 to 20 days for soft tissue depending on the number of incisions(if any), whether primary closure was needed/achieved, tissue management, and suture placement(if any).
Post operative pain varies tremendously. First off, if your someone who gets a paper cut and needs a Vicodin, then, its going to hurt a bit. If your the type that could get hit by a bus, take 2 motrin, and feel fine, then you'll have no problems. For extractions without have to lay an incison or remove any bone, then figure a couple of days of mild/moderate dull, achy sensations. For any incisions/bone removal then 3 to 7 days of moderate pain may be anticipated. MOST docs will get you a script for a narcotic (Vicodin or the like) and sometimes either a tapering steroid(solumedrol dose pack) and/or an antibiotic depending on the difficulty of the extractions.
As for who should do the extractions, ask, ask, ask. True, most 3rd molar cases are done by oral surgeons, its their bread and butter money winners(1500-2500 billing for in most cases less than 30 minutes of work), but alot of that also has to do with the ability to administer IV conscious sedation. Due to extremely large increases in mal-practice insurance fees and a relatively small(read as non cost effective need) to use this on a regular basis, most GP's aren't IV certified. Alot of GP just aren't comfortable at taking out teeth, and don't have alot of experience at it. In my residency, we didn't have an oral surgery program affiliated with the hospital I was at, hence I got to take out alot of teeth during my residency(over 4000, 175 OR cases, and 275 IV sedation cases). I feel very comfortable at extraction almoost any tooth. My partners never had such extensive training at extractions, and hence rarely take any teeth out. I still though send alot of my 3rd molar cases to the oral surgeon, simply because I want to keep my patients as comfortable as possible, and having the IV in the AC fossa with some Versed and Fentanyl flowing helps a ton! Hope that helps a bit.