These days we can synthesize gem-quality diamonds that have fewer defects than natural diamonds. See the link. Sometimes they are called "cultured diamonds". In theory they should also be less expensive than natural diamonds, but in practice, as long as the price of natural diamonds is high, and few companies are in the cultured-diamond business, synthetic diamonds can be sold for almost as much as the naturals.
Eventually, of course, competition will increase and prices will come down. When that happens, and you need to go to the dentist to deal with, say, a broken tooth, your dentist will be able to offer you a Diamond Tooth. An appropriate sized cultured diamond will be carved with an appropriate laser or ion beam, into the shape of an implantable replacement tooth.
They already have the technology to ensure that a replacement tooth on, say, the upper jaw, properly matches and intermeshes with the associated tooth on the lower jaw, so this is just a matter of carving a diamond into the shape that is currently applied to some other substance, from which they currently make replacement teeth.
A Diamond Tooth, of course, will be impervious to food acids and bacterial decay. And if you had a mouth full of them, especially at today's prices, you could quite truthfully say you had a million-dollar smile.-- Vernon, Sep 27 2012 Synthesized gem-quality diamonds http://gemesis.com/education/lab-created/As mentioned in the main text. [Vernon, Sep 27 2012] Huge Diamond Deposits Revealed In Russia http://slashdot.org.../17/2123255_1.shtml(In the news) [Sep 18] [Inyuki, Sep 27 2012] Diamond Anvil Cell http://en.wikipedia.../Diamond_anvil_cellDiamonds can withstand considerable pressure. [Vernon, Sep 28 2012] Diamond's tendency to shatter on impact may not make it the best for this.-- MechE, Sep 27 2012 // competition will increase and prices will come down ... And if you had a mouth full of them, especially at today's prices, you could quite truthfully say you had a million-dollar smile. //
You are therefore asserting that the second part is Baked, which it isn't, as the first part (large diamonds at costs economically competitive with silicon-based components) is not yet feasible.
Q.E.D.-- 8th of 7, Sep 27 2012 [MechE], when do teeth normally experience such impacts, more than, say, diamonds on rings might experience when dropped? I know diamonds are brittle, but THAT brittle?
[8th of 7], the prhase "million dollar smile" has existed for a long time, independent from most dental work. All I was saying was if this Idea was implemented today, then the phrase could become literally true. Obviously, in the future, with lower diamond prices, it wouln't be literally true. (You could still have a "flashy" smile, though. :)-- Vernon, Sep 27 2012 The ultimate bling-bling.
There might be a concern about thermal conductivity, however. The conductivity of a human tooth is (apparently) on the order of 0.0065 W/(cm*K), whereas natural diamond reportedly conducts at up to 22 W/(cm*K). Sipping hot coffee or eating ice cream could prove excruciating.-- ytk, Sep 27 2012 These exist in fiction: Terry Pratchett's trolls have diamond teeth, which hold both monetary and masticational value (but good luck trying to steal them).-- Alterother, Sep 27 2012 For reasons already mentioned diamonds are a horrible material for teeth. However diamond caps on regular teeth would be awesome if properly layered with an energy-absorbent material.-- Voice, Sep 27 2012 This could end badly unless opposed teeth are diamonded. Otherwise the diamond tooth would quickly wear away the natural one.
I also suspect that diamond teeth would be at least as tartar-prone as natural ones, and their transparency would draw attention to this.
Of course I could be wrong, but obviously that would be very unlikely.-- MaxwellBuchanan, Sep 27 2012 Perish the thought.
I remember reading something about a process for coating hard surfaces with a thin layer of synthetic diamond, but I can't remember if it was real tech, wishful thinking, or pure fiction. Anybody else know what I'm thinking of?-- Alterother, Sep 27 2012 I honestly don't know if the impact or bite force would be enough to shatter diamond but I suspect bite force might. A lot would depend on the nature of the diamond and whether it could be constructed specifically so that lines of cleavage were not in line with normal loading.
The main point, though, is that if a normal filling shatters, it's no big deal. If a diamond filling shatters, the shards would be unpleasant at best.-- MechE, Sep 27 2012 //coating hard surfaces with a thin layer of synthetic diamond// but the tooth (or false tooth) underneath it would flex, leaving the diamond layer prone to breaking.-- MaxwellBuchanan, Sep 27 2012 [Alter] It's either chemical vapor deposition diamond coating or diamond like carbon, both of which can be used as industrial coatings. Diamond is expensive, brittle, and polycrystalline (neither clear nor as hard as mono-crystalline diamond). DLC is amorphous carbon, cheaper and more flexible, but not quite as durable. I doubt either could be applied to teeth, as they both require high temperatures.-- MechE, Sep 27 2012 Platinum ?-- 8th of 7, Sep 27 2012 So, it all comes down to Joules per mol per jewels per molar as per Jules [Vernon]...-- 2 fries shy of a happy meal, Sep 27 2012 You guys are harsh. Vernon, I probably cant afford the full set but would be happy with some rubberised Cubic zirconia or perhaps a titanium carbide set of gnashers if I want to push the boat out.
I seriously doubt there will be any shattering of teeth.
I once bit a radiator while playing peekabo and surprisingly got away with minimal damage, which considering the force involved was remarkable.-- PainOCommonSense, Sep 27 2012 Jules Vernon, as in "Journey to the Centre of the Tooth", "Twenty Thousand Fillings under the Sea" and "From the Lips to the Gums" ... ?-- 8th of 7, Sep 27 2012 ... Jules Vernon's "The Varnished Diamond" or "Clovis Dar-dentine"-- PainOCommonSense, Sep 27 2012 Okay, best information I can find (which is not very good) says diamonds can shatter under as little as 2 MPa, ~290 PSI. Human bite pressure is only ~120 PSI. If that's true, it would be safe enough, but I'm still not convinced you wouldn't have problems if the bite pressure happened to align along a normal cleavage plane. Not shattering, just splitting.-- MechE, Sep 27 2012 Platinum, definitely.-- 8th of 7, Sep 27 2012 I'm voting nanotube impregnated stainless steel with a saphire coating.
As for plaque you could scrub as hard as you want with a toothbrush as long as you don't do the gums...-- Voice, Sep 27 2012 //best information I can find ... says diamonds can shatter under as little as 2 MPa//
You're right about that information not being very good. Is that tensile stress or compressive? If it's compressive, then it's wrong. In fact any figure for the compressive strength of any material is wrong. Compressive strength depends hugely on geometry.
An inch-diameter pillar of wood, one inch tall, will support several hundred pounds of compression. An inch diameter pillar of wood twenty feet tall will fail by bowing and folding. Compressive strength is hugely geometry dependent; tensile strength less so.-- MaxwellBuchanan, Sep 27 2012 Yay, cement dentures. Eat your food the Blue Circle way. No need to clean, just throw 'em away and pop in another set. So what if your teeth are a dull grey colour? It's never bothered Mitt Romney …-- 8th of 7, Sep 27 2012 [MB] Ultimate compressive strength is not dependent on geometry. I admit ultimate compressive load is, since for ductile materials, the tendency to become shorter but with a larger cross section under load makes them stronger. Since diamond is very brittle, I wouldn't expect that to be a problem here.
Of course a compressively loaded structure can fail in other modes, as you describe, but if you can find a diamond with a narrow enough aspect ratio to fail in buckling, I'll be surprised.-- MechE, Sep 27 2012 So that once the future archelogists unearth a crystal skull with diamond teeth, they know that we had the technology to make it?-- Inyuki, Sep 27 2012 //Ultimate compressive strength is not dependent on geometry.// Tis so. A gapless material cannot "fail" by pure compression (you can't make a crack in something by pushing its atoms closer together); the closest it can get is plastic deformation (ie, squeezing out sideways).
Diamond will only break by tension. A compressive load can generate local tensions, but the size of these tensions will depend not only on the compressive force applied, but also very much on the geometry. (Extreme case - make a U- shaped diamond and squeeze the ends together; the diamond will crack in tension at the base of the U.)
If I'm wrong, explain to me how a crack can form in a diamond by pushing the atoms closer together.-- MaxwellBuchanan, Sep 27 2012 Even if it is failure in tension on a microscale (it's not, a lot of shear going on as well), the loading is purely compression, and it's relatively consistent for a given material. Not as consistent as tension, I admit, but even tensions is highly vulnerable to defects in the material.-- MechE, Sep 27 2012 I will agree that the thermal conductivity problem puts a big dent in this Idea. Perhaps a solution can be found in the way a Diamond Tooth is attached to the bone. That is, perhaps a suitable thermal insulator can be included.
[21Quest], the main text plainly states that the diamond has to be carved into the appropriate shape, to match the opposing tooth (whether also diamond, or natural). I suggested ion beams as a possible method for doing that. Lasers would probably work not-so-well for the carving task, because diamond is quite transparent, including to many UV frequencies.-- Vernon, Sep 28 2012 You're thinking of graphite. Diamond is tetrahedral. And while on an atomic scale the cleavage planes are important, on the macro scale of a synthetic tooth the approximation of a curve by a sequence of linear facets is perfectly acceptable.
Carbon atoms are nanometres in diameter; teeth are millimetres across. There's at least six orders of magnitude difference in the scale of the features.-- 8th of 7, Sep 28 2012 //can a crystalline structure BE carved into a curve, without shattering?//
Yes. Metals, salt, ice...all crystalline and can be carved, ground, cut or lasered into any shape you like.-- MaxwellBuchanan, Sep 28 2012 The reason you never see curved diamond surfaces (unlike other gemstones with chacobon cuts) is that the majority of a diamonds attractiveness is how it behaves in light, which is emphasized by facets, not smooth surfaces.
And Vernon, as far as your link, diamonds can withstand huge pressures, but they can also be cut by a fairly light hit, or shattered with a hammer. Diamonds are extremely anisotropic, and can be a couple orders of magnitude between their strongest and weakest plains. The diamonds used for anvils are carefully selected and positioned so that doesn't happen, but I think that would be difficult for teeth.-- MechE, Sep 28 2012 [MechE], well, the Idea does specify lab-grown gem-quality diamonds, which can have many fewer internal flaws than natural diamonds. That should make a difference, with respect to withstanding chipping or other breakage.-- Vernon, Sep 28 2012 I don't think lab-grown vs. natural makes much of a difference in that respect. As I once mentioned in annotation to another diamond- related post, I have shattered a lab-grown diamond with a single blow from a 3lb drilling hammer. Actually, 'pulverized' might be a better word. Perhaps it was the lack of internal flaws which caused it to reduce to such a fine powder.-- Alterother, Sep 28 2012 This leads inexorably to the conclusion that the answer to the problem is not to create flawless synthetic carbon crystals, but rather carefully controlled chaotic structures which diminish the susceptibility to failure along cleavage planes.
High quality steels exhibit similar "controlled chaos" in their crystal structure.
We still assert that Platinum offers a superior material to meet the specification. Corrosion resistant, won't shatter, machinable (within limits), biologically inert.-- 8th of 7, Sep 28 2012 It's not flaws that are the issue, it's how you hit the diamond in relation to its crystal structure.-- MechE, Sep 28 2012 If anyone has several spare diamonds handy, I'll be happy to smash them from a variety of different angles. Many of you know more about this than I do, but isn't the basic issue simply that diamonds are very brittle?-- Alterother, Sep 28 2012 Has anyone suggested platinum then?-- AusCan531, Jan 27 2013 Or later? Given the money I've spent on dentistry, I may as well be using gold, diamonds, and platinum.-- normzone, Jan 27 2013 random, halfbakery