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Why Are Human Teeth So Messed Up? (2017)

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Re: Why Are Human Teeth So Messed Up? (2017)

#61

Post by zachguo »

keithwhor wrote: post #22

Isn't an alternative explanation just that well-aligned jaws and spaced teeth are selected for via both (A) natural selection, esp. in predator species (well-aligned jaw = more efficient prey capture, chewing, defense) and (B) sexual selection as a holdover result of the first? As in, if ancestors relied heavily on their jaws and, behaviourally, a selective preference for well-aligned jaws and teeth helped favor offs…

One can also interpret it as that, once human learnt to use fire, cooked food made jaws and teeth less important, so people with bigger brain would reproduce more, no matter how their teeth look like.

There's also cultural difference in the aesthetics of teeth, for example, Japanese culture considers yaeba as cute.

Re: Why Are Human Teeth So Messed Up? (2017)

#62

Post by evmar »

mgiampapa wrote: post #46
skc wrote: post #40

Teeth are annoying. Mine are ok, but as I get older I start to notice their deterioration. I've always felt that if there was a part of our anatomy that we should think of replacing completely with an artificial design, it's teeth. We already do so now (at great expense), but it's literally one or two teeth replaced but I'm thinking more along the lines of replacing every single one with something stronger and more e…

This used to be quite common. In Ireland for example back in the 1970s about 30% of the population had no natural teeth whatsoever. It used to be a common thing for young women to have all their teeth pulled and replaced with dentures before being married. It was seen as a desirable trait for en eligible bride to be.

This is still common. I recall the anecdote that there is one US state where one in four people have no teeth, due to getting them all pulled, though I can't find the data now.

My wife is a dentist. One of her classmates told the story of their parent's dental practice, where someone had taken their teenager in, discovered they needed some expensive dental work, and said "take out all the teeth, they're gonna fail eventually anyway".

Re: Why Are Human Teeth So Messed Up? (2017)

#63

Post by chronogram »

evmar wrote: post #62
mgiampapa wrote: post #46

Earlier quoted context omitted.

This used to be quite common. In Ireland for example back in the 1970s about 30% of the population had no natural teeth whatsoever. It used to be a common thing for young women to have all their teeth pulled and replaced with dentures before being married. It was seen as a desirable trait for en eligible bride to be.

This is still common. I recall the anecdote that there is one US state where one in four people have no teeth, due to getting them all pulled, though I can't find the data now. My wife is a dentist. One of her classmates told the story of their parent's dental practice, where someone had taken their teenager in, discovered they needed some expensive dental work, and said "take out all the teeth, they're gonna fail ev…

How does a parent have the ability to say that over some teen's body..? It's horrible to me to read that people would just say that.

Re: Why Are Human Teeth So Messed Up? (2017)

#64

Post by madaxe_again »

skc wrote: post #40

Teeth are annoying. Mine are ok, but as I get older I start to notice their deterioration. I've always felt that if there was a part of our anatomy that we should think of replacing completely with an artificial design, it's teeth. We already do so now (at great expense), but it's literally one or two teeth replaced but I'm thinking more along the lines of replacing every single one with something stronger and more e…

I’m a freakishly lucky bastard, to date. Also, a freak.

I have a fairly gracile jaw for a guy. A bit of a chinless wonder. I have 28 teeth. Always have, since my adult teeth came through - but I do have wisdom teeth. What I don’t have are any M1 molars. They’re just not there. Seems my maternal grandfather and my sister are the same.

I’m 35, with so-so at best oral hygiene. Never had a cavity, never had a filling, never needed orthodontics - and really weirdly neither has my grandfather - he’s 86 with a complete and unaltered set of original gnashers. A bit worn down after seven decades, but all still there and working. My mother lost all of hers in a motorbike crash decades ago so there’s no telling there.

So - while I think the idea of artificial replacements is a perfectly good one, there should perhaps be some research into pheno/genotypes such as my family’s which seems to have a useful mutation for the incredible shrinking jaw. It’s this sort of thing which could be a valid use of gene editing - it doesn’t really present any advantages other than being able to eat.

Re: Why Are Human Teeth So Messed Up? (2017)

#65

Post by osdiab »

What are the aesthetic consequences of having a more developed jaw from chewing tough foods as you grow? Given how sensitive people are to cosmetics when it comes to their teeth, would doing this to your child positively impact their dental outcomes at the expense of conformance with modern norms of physical attractiveness, given trends like how having a small face is seen as attractive in Asia, or soft jawlines for women?

I pose this since it is likely many people would worry about aesthetics more than actual dental health, and also because the social consequences of being/not being conventionally attractive can have significant impact on people's lives as well, so answering this sort of stuff is probably necessary for actual behavior change.

Re: Why Are Human Teeth So Messed Up? (2017)

#66

Post by findthewords »

forgotmypw3 wrote: post #15

In addition to all the other arguments here (more chewing for bigger jaw development), I have another theory about tooth decay. I think that pre-civilization humans did not eat much sweets past adolescence. This is because, as soon as a minor cavity starts developing, it hurts like hell to put anything sweet in your mouth. Sweet stuff was for children and adolescents, then we just stopped eating it.

That pain is caused by nerve-connected dentin.

Unless the cavities go all the way through, recessed gingiva expose cementum that erodes, exposing dentin.

It's the same sugar-loving bacteria that inflame the gums.

Re: Why Are Human Teeth So Messed Up? (2017)

#67

Post by zawerf »

mgiampapa wrote: post #46
skc wrote: post #40

Teeth are annoying. Mine are ok, but as I get older I start to notice their deterioration. I've always felt that if there was a part of our anatomy that we should think of replacing completely with an artificial design, it's teeth. We already do so now (at great expense), but it's literally one or two teeth replaced but I'm thinking more along the lines of replacing every single one with something stronger and more e…

This used to be quite common. In Ireland for example back in the 1970s about 30% of the population had no natural teeth whatsoever. It used to be a common thing for young women to have all their teeth pulled and replaced with dentures before being married. It was seen as a desirable trait for en eligible bride to be.

Why is it a desirable trait for eligible brides specifically? Are you implying something about the country's preferences for toothless blowjobs or do I just have a dirty mind?

Re: Why Are Human Teeth So Messed Up? (2017)

#68

Post by MaysonL »

keithwhor wrote: post #22

Isn't an alternative explanation just that well-aligned jaws and spaced teeth are selected for via both (A) natural selection, esp. in predator species (well-aligned jaw = more efficient prey capture, chewing, defense) and (B) sexual selection as a holdover result of the first? As in, if ancestors relied heavily on their jaws and, behaviourally, a selective preference for well-aligned jaws and teeth helped favor offs…

Both of my parents had well-aligned jaws with teeth suited to them. Unfortunately for my elder brother and myself, we had our father's teeth in our mother's jaws. Crowding ensued, not helped by the fact that both of us have a couple of senility teeth (my neologism for our fifth molars).

Re: Why Are Human Teeth So Messed Up? (2017)

#69

Post by gwern »

lettergram wrote: post #51
mgiampapa wrote: post #46

Earlier quoted context omitted.

This used to be quite common. In Ireland for example back in the 1970s about 30% of the population had no natural teeth whatsoever. It used to be a common thing for young women to have all their teeth pulled and replaced with dentures before being married. It was seen as a desirable trait for en eligible bride to be.

Do you have a citation on that, I’m genuinely curious about the stats on that.

I don't know about Ireland, but I did recently look up the same statistics for the UK: https://www.gwern.net/Questions#physical-beauty You can source it to the UK national dental surveys (which wouldn't be surprising if they covered Ireland as well), for example, https://archive.org/details/np70033823/page/n1

Re: Why Are Human Teeth So Messed Up? (2017)

#70

Post by [deleted] »

osdiab wrote: post #65

What are the aesthetic consequences of having a more developed jaw from chewing tough foods as you grow? Given how sensitive people are to cosmetics when it comes to their teeth, would doing this to your child positively impact their dental outcomes at the expense of conformance with modern norms of physical attractiveness, given trends like how having a small face is seen as attractive in Asia, or soft jawlines for…

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