From the movie that remains, to this day, my favorite comedy, 1965's The Great Race:
Larry Storch's character, Texas Jack, says to Tony Curtis' always-spotless-white The Great Leslie: "Now can ah have me some fahh-tin' room?" in a schtick that repeats several times; sorry, tahmes, each more hilarious than the last. Here's the clip:
Well, it is hilarious to a guy like me, who appreciates the slower, kindlier humor of that bygone era to today's often highly mean-spirited stuff. So many things in our culture have improved, but I submit that film is not one of them.
And so that Texas Jack clip is what I think of when I see prior dental treatments that fail partly because there wasn't enough "fahh-tin' room", or enough space for the restorative materials that we so often place in and on teeth in order to keep them going after they've been harmed by decay, fractures or just overall wear.
There are many types of dental crowns. The workhorse of the 20th and early 21st Century is the porcelain fused to metal, or PFM. This type of crown has a layer of semi-precious or non-precious metal, cast or milled, covering the tooth. The functional shape and esthetic look is then completed by porcelain layered on top and around the sides. Nine out of ten dentists, and eleven out of ten dental educators, assert that the materials involved in a PFM need to be at least 2 mm thick on the biting surface of the tooth.
Another way of looking at this is, we need to remove enough old filling and tooth to provide 2 mm of clearance between the opposing teeth and the one we're working so hard to restore.
Here is a pair of images of an old crown that I removed and sectioned:
The striking thing to note is that the porcelain on top of the tooth, on the biting surface, is very thin. Yes, it wore a bit over the years that this crown was in service. But porcelain wears slower than opposing teeth, when it is properly placed onto the metal. This crown started out on an underprepared tooth. It wasn't given enough fahh-tin' room between the top of the crown prep and the opposing teeth. Thus, the porcelain was very thin. The deeper layers of porcelain are opaquers and coarse layers that are not as effecive as the final ones at holding up to the rigors of chewing day after day. Thus, they wear away quickly and what was at first a thin layer becomes an uber-thin layer that tends to fracture.
It is said that the rate of porcelain fracture in new crowns done in America at this point is about 5% over the first five years. This includes every kind of fracture, from big ones that render the crown unserviceable and in need of replacement down to minor fractures that can simply be polished away. Still, everything we can do in dentistry to minimize treatment failures is important, and ensuring adequate reduction of our crown preps is vital.
Patients- if you ever have a "PFM" crown done and the biting surface shows metal or looks very odd compared to the beauty of the rest of your crown; say, opaque and flat-looking, rather like a lawn ornament (I'm thinking plastic pink flamingo here); then there was probably an issue with the clearance between the treated tooth and the ones that oppose it. This truly should be corrected before your new crown is cemented into place, only to face a high likelihood of breaking in a short time.
Returning to important matters, the scene in the above Youtube clip must certainly be the greatest bar fight ever put on film. Barstools fly. Bottles are smashed. When the staircases come down, it's just magnificent. And there's that quirky exchange between Lily Ole and The Great Leslie early in the clip:
Lily: "Honey, your smile is downright painful!"
Leslie: "Thank you. Are you a native of Boracho?"
Indignant Lily: "I ain't no native, I was born here!"
But the pie fight... oh yes, the pie fight. Definitely, at 2,357 pies, the grandest pie fight ever on film.
You will not regret watching it!
"Y-o-u w-o-u-l-d-n-t d-a-r-e!"