# What do I need to know about dental cavities and their repair? **URL:** \ **Category:** Factual Questions\ **Created:** [October 12, 2010, 11:22pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931 "2010-10-12T23:22:04Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![dzero](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dzero](https://boards.straightdope.com/u/dzero)\ **Post date:** [October 12, 2010, 11:22pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/1 "2010-10-12T23:22:04Z")
I was talking to a friend of mine about some dental problems and realized that a lot of people don’t necessarily understand what’s involved in the process of dental decay. For example, there is a difference between the enamel that protects a tooth and the dentin that provides the underlying structure. While this may seem obvious to many here, I can assure you that if my friend was unaware of this fact, so are any number of other people. Here’s one that it took me many years to realize although in retrospect I guess it too is sort of obvious. When you get a cavity between teeth (which means you haven’t been flossing - yes we know that you don’t floss), the dentist has to drill in from the top of the tooth in order to repair it. God, reading that now I feel so stupid. In my defense I think I always assumed that the those were fillings due to cavities on the chewing surface. After all, when you’re numbed out from the anesthetic, you don’t really realize how far down their drilling (yo doc, you strike oil yet). Some specific questions: - is there a specific type of bacteria that is responsible for decay and if so, how did it get dibs on my teeth over its many competitors. - what is the actual decay process? Is it just the acid produced by the bacteria that is the cause or is there more to it. Why isn’t the acid washed away by saliva? So good SDMB denizens, banish my ignorance regarding dental medicine. ---
**Author:** ![dzero](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dzero](https://boards.straightdope.com/u/dzero)\ **Post date:** [October 13, 2010, 8:28pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/2 "2010-10-13T20:28:33Z")
bump. I think this will be very useful to a lot of people and doing a search on cavity and cavities didn’t turn anything up in the past year or two that has the same wide scope. ---
**Author:** ![pudytat72](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@pudytat72](https://boards.straightdope.com/u/pudytat72)\ **Post date:** [October 13, 2010, 11:08pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/3 "2010-10-13T23:08:38Z")
One thing that I recently learned, is that the surface of a tooth may look normal, but there can be a large amount of decay under the surface. Google Images for dental cavities is interesting. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [October 13, 2010, 11:17pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/4 "2010-10-13T23:17:49Z")
**What do I need to know about dental cavities and their repair?** Nothing. Your Dentist knows that, and will take care of it for you. All you need to know is basic preventative care for your teeth (brush at least daily, floss regularly, brush/massage gums periodically, etc.) Most of which hasn’t changed since your mother taught you that as a child. (It just gets more important to an older adult with aging teeth!) ---
**Author:** ![dzero](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dzero](https://boards.straightdope.com/u/dzero)\ **Post date:** [October 13, 2010, 11:42pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/5 "2010-10-13T23:42:13Z")
> [@pudytat72](#): > > One thing that I recently learned, is that the surface of a tooth may look normal, but there can be a large amount of decay under the surface. Google Images for dental cavities is interesting. My friend said something like that. It didn’t make any sense to me since there are no blood vessels in the dentin and if the enamel is in tact, it should prevent any damage to the dentin. But that’s why I’m asking these things. I think I understand but a lot if what I know I’ve picked up from my dentist. He loves to talk about it and I love asking questions. The problem is that you never know how much they’re dumbing it down for you. ---
**Author:** ![mere\_mortal](https://avatars.discourse-cdn.com/v4/letter/m/f4b2a3/32.png) [@mere\_mortal](https://boards.straightdope.com/u/mere_mortal)\ **Post date:** [October 14, 2010, 1:23am UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/6 "2010-10-14T01:23:51Z")
> [@t-bonham@scc.net](#): > > **What do I need to know about dental cavities and their repair?** > > Nothing. Your Dentist knows that, and will take care of it for you. > > All you need to know is basic preventative care for your teeth (brush at least daily, floss regularly, brush/massage gums periodically, etc.) Most of which hasn’t changed since your mother taught you that as a child. (It just gets more important to an older adult with aging teeth!) I’m 😕. I brush twice a day, floss daily, brush and massage my gums periodically and I still have numerous cavities. My previous dentist did a check-up and not even three weeks later, I had to go back for a “big” [those were her words, not mine] cavity that needed to be filled that she missed. Don’t have much trust in dentists now and yes, did the obvious, switched providers. Also I learned something interesting today. My doctor told me that teeth were only meant to last forty years since that was the “average” lifespan of a human before life expectancy increased greatly. In other words, at 40, I am middle age but my teeth are elderly? I was really feeling my age today. Basically, he said I can expect a lot of problems or maybe politely meant I’m old. Are dental problems or characteristics hereditary? Am I more prone or susceptible to dental problems because of my genes? ---
**Author:** ![Marley23](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Marley23](https://boards.straightdope.com/u/Marley23)\ **Post date:** [October 14, 2010, 10:58am UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/7 "2010-10-14T10:58:19Z")
> [@mere\_mortal](#): > > Also I learned something interesting today. My doctor told me that teeth were only meant to last forty years since that was the “average” lifespan of a human before life expectancy increased greatly. In other words, at 40, I am middle age but my teeth are elderly? He’s wrong. It’s true that average life expectancy increased a lot during the 20th century, but 40 has never been elderly. In the past, death during infancy and childhood was a lot more common. If you lived past age 5 or so, you had a good shot of living until you were maybe 60 or 70. But if you average out all the people who were dying at 5 and under with people who died of old age, you can get an average life expectancy of something like 40. (This is one of the ways averages can be misleading.) So no, your teeth were not “meant” to last only 40 years. On the other hand it’s true that dental care has improved a lot in the last few generations. Your dental problems would probably have been worse if you lived before fluoridation, never mind a century or two ago or more. ---
**Author:** ![mere\_mortal](https://avatars.discourse-cdn.com/v4/letter/m/f4b2a3/32.png) [@mere\_mortal](https://boards.straightdope.com/u/mere_mortal)\ **Post date:** [October 14, 2010, 11:54am UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/8 "2010-10-14T11:54:17Z")
Thanks for straightening things out. And I’ll tell my orthodontist same thing. ---
**Author:** ![Marley23](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Marley23](https://boards.straightdope.com/u/Marley23)\ **Post date:** [October 14, 2010, 2:28pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/9 "2010-10-14T14:28:47Z")
No problem. I would think that evolution is going to work in favor of longer lasting teeth anyway - because people who have healthier teeth would probably live longer and so they’d reproduce more - at least to the extent that dental health is genetic. ---
**Author:** ![Lare](https://avatars.discourse-cdn.com/v4/letter/l/53a042/32.png) [@Lare](https://boards.straightdope.com/u/Lare)\ **Post date:** [October 14, 2010, 3:27pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/10 "2010-10-14T15:27:45Z")
> [@mere\_mortal](#): > > Thanks for \*\*straightening \*\*things out. And I’ll tell my \*\*orthodontist \*\*same thing. (added bolding) Hahahaha I don’t know the specifics of good genes WRT tooth decay, but my anecdotal comment is that my last dentist commented on how strong my teeth seemed to be but how many cavities I had. My Mom had very bad teeth (lost them all before middle age) and my Dad has great ones (still has all but one in mid-80’s). ---
**Author:** ![mere\_mortal](https://avatars.discourse-cdn.com/v4/letter/m/f4b2a3/32.png) [@mere\_mortal](https://boards.straightdope.com/u/mere_mortal)\ **Post date:** [October 14, 2010, 8:38pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/11 "2010-10-14T20:38:19Z")
> [@mere\_mortal](#): > > Thanks for straightening things out. And I’ll tell my orthodontist same thing. If my **orthodontist** knew if teeth problems were genetic, I could have **braced** myself for the news. ---
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [October 14, 2010, 8:51pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/12 "2010-10-14T20:51:32Z")
I’ve long wondered what accounts for the varying health and durability of teeth in different people. I know plenty of people who don’t eat a lot of sweets or acidic foods and obsessively brush, floss, and regularly visit their dentist but constantly have cavities and other problems while other people, like myself, take less-than-great care of their teeth (I may forget to brush every single day, and what the hell is this floss shit I keep hearing about?), and yet have, at 33 years old, still never had a cavity or needed the dentist to do anything more than a routine cleaning. Is it just genetics? ---
**Author:** ![curious11](https://avatars.discourse-cdn.com/v4/letter/c/ac91a4/32.png) [@curious11](https://boards.straightdope.com/u/curious11)\ **Post date:** [October 14, 2010, 8:57pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/13 "2010-10-14T20:57:38Z")
> [@Marley23](#): > > I would think that evolution is going to work in favor of longer lasting teeth anyway - because people who have healthier teeth would probably live longer and so they’d reproduce more - at least to the extent that dental health is genetic. That is not entirely true, they would have probably already reproduced by the time that the “long lasting” teeth provided an advantage. ---
**Author:** ![davekhps](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@davekhps](https://boards.straightdope.com/u/davekhps)\ **Post date:** [October 15, 2010, 3:40pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/14 "2010-10-15T15:40:34Z")
> [@curious11](#): > > > [@Marley23](#): > > > > I would think that evolution is going to work in favor of longer lasting teeth anyway - because people who have healthier teeth would probably live longer and so they’d reproduce more - at least to the extent that dental health is genetic. > > That is not entirely true, they would have probably already reproduced by the time that the “long lasting” teeth provided an advantage. This, and what advantages are afforded by healthier teeth nowadays anyway? Science will figure out how to re-grow teeth long before evolution gets around to changing it for us. ---
**Author:** ![dzero](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dzero](https://boards.straightdope.com/u/dzero)\ **Post date:** [October 15, 2010, 4:11pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/15 "2010-10-15T16:11:25Z")
> [@curious11](#): > > > [@Marley23](#): > > > > I would think that evolution is going to work in favor of longer lasting teeth anyway - because people who have healthier teeth would probably live longer and so they’d reproduce more - at least to the extent that dental health is genetic. > > That is not entirely true, they would have probably already reproduced by the time that the “long lasting” teeth provided an advantage. Yes, but the longer you live, the more progeny you can create - definitely true for women but also true for men. Over time, individuals that produce 10 or 15 progeny will overwhelm those producing only 3 or 4 and make them the small minority in the new, improved gene pool. ---
**Author:** ![LouisB](https://avatars.discourse-cdn.com/v4/letter/l/dfb087/32.png) [@LouisB](https://boards.straightdope.com/u/LouisB)\ **Post date:** [October 15, 2010, 5:30pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/16 "2010-10-15T17:30:51Z")
In two weeks, I will sit down in a dental surgeons chair and have ALL my remaining teeth extracted. I think I have maybe twenty teeth left and some of those are broken (at least three at the gum line) and nearly all of them have far too much damage to be repaired. The surgeon has promised me two things: His extractions will be pain free until the drugs wear off and then I will be in spectacular pain. He is fully aware of my drug addiction problems and seems to be eager to test my fortitude; he doesn’t do sedation dentistry. IF I survive, which I will, I will go through a certain amount of grief having dentures fitted; all of this will cost me several thousand dollars. So, regarding the care of one’s teeth: Do whatever your tooth fairy professional recommends. I wish I had. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [October 15, 2010, 5:33pm UTC](https://boards.straightdope.com/t/what-do-i-need-to-know-about-dental-cavities-and-their-repair/556931/17 "2010-10-15T17:33:29Z")
> [@davekhps](#): > > > [@curious11](#): > > > > That is not entirely true, they would have probably already reproduced by the time that the “long lasting” teeth provided an advantage. > > This, and what advantages are afforded by healthier teeth nowadays anyway? Science will figure out how to re-grow teeth long before evolution gets around to changing it for us. They say bad teeth affect your cardiac health, actually.