Dearest Straight Dope,
I believe I have come up with the ultimate in questions. Is the human jaw so imperfectly ‘put together’, that if you put a lightbulb in your mouth, you could not take it out without either A) dislocating your jaw, or B) breaking the bulb (ouch! shards of glass)? For this question, we shall assume it’s a 60watt or higher bulb that comfortably fits in the mouth cavity. (To see a ‘story’ that often gets told in regards to this question, go here: http://www.skyfly.cz/zajimavo_e/zarovka_e.htm )
I would assume that if you can get it in, you sould be able to getting it out by stretching your jaw the same way.
Where’s Linda Lovelace when you need her?
Makes a good story. But that’s all it makes.
Well, if it wasn’t true, there must be some sort of roots to this story. Anyone willing to conduct an experiment?
Yes I rmeber reading about this in the ‘True Stories’ section of a popular UK gentlemen’s magazine. It does sound to me though very much like an Urban Legend.
So it could be a true story, or it could be an urban legend. I think the people who do know the answer have their mouths shut about it… or a mouth full of light bulb.
I’ve heard a similar story with billiard balls.
I just put a regular 60W light bulb in my mouth as far as it would go, and it came right back out in the same manner. I have had my wisdom teeth removed, but otherwise have the normal adult number of teeth. Oh, and the light bulb was wet because I washed it off first, but that shouldn’t make a difference, right?
Perhaps a slightly larger bulb then. Something that completely fills your mouth. If you could accompany your experiment with a picture, in the name of science, we would all be much obliged.
A disclaimer.
Do not attempt.
Although Chorpler’s experiment was reportedly successful, we here at the SDMB do not encourage such death-defying stunts.:eek: Chorpler is a world-reknowned stunt poster, and your jaw may not be structured in the same way. Although some of us may have done some damnfool thing or other without calamity, REMEMBER the mods and The Chicago Reader never told them to. Nope, not once.
I have found that telling people not to do something makes them want to do it that much more. 
Believe me, the 60W bulb is about as big as my mouth could fit – my jaw’s joints still hurt from stretching large enough to fit the thing. The bulb was too wide to fit into the horizontal space between my molars, so it was all in-between the chewing surfaces of my upper and lower teeth.
The part of the bulb extending from my mouth, incidentally, was the entire metal collar, plus about 3/4" of glass.
As for a photo, my kids accidentally destroyed my old digital camera by ripping off the battery door, but I’ll see if I can borrow one and take a photo. 
An episode Of MASH guest-starred a young George Wendt(Norm Peterson of Cheers) as patient who had lost a bar bet. He now had a billiard ball(I can’t be sure, but I think it was the 8 ball) lodged in his mouth.
Dr Winchester was able to remedy this by injecting a muscle relaxant. IANA doctor but I believe this would be the actual course of treatment. It should create enough room to allow the object to be removed and is both less painful and less complicated than dislocating the jaw.
NOTE- Should you feel compelled to try this, please do NOT use a lightbulb. Find a similarly sized object which is not made of glass. My opinion is that removal of the object is dependant on the mandible and dentition of the individual. You may be able to remove the thing again. You may need medical help. In either case, a bulb may accidentally be shattered. This will almost certainly be bloody and painful and could well be fatal. A tennis ball, billiard ball, or object of similar size will serve the cause of science just as well and be much safer.
Hmmmm… I wonder, if it would get stuck, why it wouldn’t come out.
Difficulty in removing the light bulb might be dow to its structural properties; spheroids are generally stronger in compression than tensio, so in pushing it into your mouth, you are exerting pressure upon the top as it squeezes between your teeth, and on the stem as you push. On the way out, you are pulling (exerting tension) on the stem, which is likely to break with less force than it took in compression.
There’s also the problem of swelling – I think we’ve all had rings that wouldn’t come off because the finger swelled. I imagine that if you insult the jaw muscles sufficiently getting the lightbulb in, they might swell up or tighten, making it impossible to withdraw the bulb.
As for the OP’s use of the word “imperfect” – it’s difficult to imagine the ability to withdraw a lightbulb from the mouth being an evolutionary advantage. (Even to Chorpler’s gene pool as he apparently already has kids.)
I have an orange that is slightly larger then a lightbulb.
I figured the orage would be safe to try because the glass content is so low in this type of orange.
Ok,. here it goes.
places orange in mouth
mrrrrff meeeffr meer uuurfuuf mrrruf
*takes orange out of,. oh wait… uh oh. *
mmmmuuuuurrrrrffff!!!
takes orange out of mouth
Just kidding. There you go. No problem.
Or Uncle Fester?
I can’t believe I almost forgot to mention; I once pushed a tomato whole into my mouth (I honestly don’t know why) - the fruit was reasonably large and it fit very snugly; I couldn’t remove it because my cheeks/lips were stretched so tight that I couldn’t get even one finger into my mouth to get behind it, neither could I push it out with my tongue because it was pinned to the bottom of my mouth (and you can’t push very hard with your tongue anyway).
The tomato was quite firsm, so I couldn’t simply crush it with my jaws either - to do so caused it to press against the roof of my mouth with unbearable discomfort.
Twelve years later, I still have a large tomato stuck in my mouth.
Not really; I had to take a table knife to the rest rooms and carefully cut the tomato up in front of a mirror (did I mention that this happened in a restaurant?)
[QUOTE]
*Originally posted by Mangetout *
Twelve years later, I still have a large tomato stuck in my mouth.
THAT is one of the funniest laugh-out-loud deadpan lines I have seen on the Board. Thanks so much.