Why humans need to brush their teeth

[Blue Scallop]

Why do humans get cavities if the teeth are not brushed whereas animals like dogs, cats and horses don't have cavities?

 

[tech99]

Why do humans get cavities if the teeth are not brushed whereas animals like dogs, cats and horses don't have cavities?

I am told that the Western diet contains a lot of sugar, which feeds bacteria, which produce plaque, which is acidic and which reacts with the soft enamel of the tooth.

 

[Drakkith]

I am told that the Western diet contains a lot of sugar, which feeds bacteria, which produce plaque, which is acidic and which reacts with the soft enamel of the tooth.

That's my understanding as well. I've read of human societies, such as certain tribes in Africa, who have very low rates of tooth decay thanks to their diet containing very little raw sugar or even fruits.

 

[jim mcnamara]

Incidence of dental caries is related to diet. This study indicates pastry consumption is correlated with root caries (root canal, ouch).
Example: https://www.ncbi.nlm.nih.gov/pubmed/19490135

This: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921667/
discusses how Somali refugees have adapted from using stick brushes to toothbrushes. Tangentially it appears that the original oral health practices were related to religious practice, and so older people were very firm adherents.

My conclusion: tooth brushing or cleaning is common among many groups of humans.

 

[BillTre]

Dogs and Cats can get cavities.

"dogs: 5 percent
cats: very rare (almost nonexistent)"

I find it interesting that cats cannot taste sweets while dogs can.

 

[rootone]

Bacteria is why humans get dental decay, personally I prefer to just daily use a strong mouthwash instead of a brush.
Other animals also can dental problems, but don't usually invite bacteria's by thowing a sugar party every day,

 

[Drakkith]

Bacteria is why humans get dental decay, personally I prefer to just daily use a strong mouthwash instead of a brush.
Other animals also can dental problems, but don't usually invite bacteria's by thowing a sugar party every day,

Hmmm. It was my understanding that mouthwash doesn't kill the bacteria that cause plaque and tooth decay. I'll have to look into this.

 

[rootone]

Well my understanding is that while this is not guaranteed to be 100% reliable, it's around the same as brushing is.
Not claiming to be a dental expert though, dental experts feature in my worst nightmares.

 

[OCR]

Well my understanding is that while this is not guaranteed to be 100% reliable, it's around the same as brushing is

Heck, stick with the mouthwash...

Teeth brushing can actually cause bacteremia.

Transient bacteremia can result after dental procedures or brushing of teeth.

Gram positive bacteremia...

Viridans streptococci species are normal bacterial flora of the mouth. Viridans strep can cause temporary bacteremia after eating, toothbrushing, or flossing. More severe bacteremia can occur following dental procedures or in patients receiving chemotherapy.

 

[symbolipoint]

Well my understanding is that while this is not guaranteed to be 100% reliable, it's around the same as brushing is.
Not claiming to be a dental expert though, dental experts feature in my worst nightmares.

... and ignoring what the dental experts tell you can and often DO lead you to dental decay problems and gum problems which lead to much higher dental and gum disease trouble, so inviting more of those nightmares.

 

[hilbert2]

Not everyone would lose their teeth even if they never brushed them (especially if they were on a stone age hunter-gatherer diet) but it's definitely worth it to do that to avoid the risk of huge medical bill from repairing totally destroyed teeth and the risk of sepsis/systemic infection that can happen if you have untreated cavities for a long time.

 

[Choppy]

I might challenge the premise that dogs and cats don't get cavities. I suspect they do - just probably not with the same frequency as humans.

I know many veterinarians offer tooth cleaning services. And if you've even owned a dog, you'll understand that dogs aren't exactly known for having nice breath. I suspect it's the same with cats - their mouths are just smaller. And animals can't exactly tell you when their teeth are irritating them. They would just live with a tooth problem until it becomes noticeable in behaviour to an owner.

And you also have to factor in lifespan. A dog does pretty good if it gets into its early teens. Some cat breeds can reach their twenties. But people have much longer lifespans and therefore have a lot longer for teeth to decay, or for other tooth problems to develop.

I remember with my last dog we had to brush his teeth. He didn't like it that much and kept trying to chew on the toothbrush.

 

[Drakkith]

Heck, stick with the mouthwash...

Teeth brushing can actually cause bacteremia.

The reference provided in the bacteremia article talks about transient bacteremia:

Transient bacteremia from oral cavity related to oral anaerobic bacteria may occur as a result of dental healthcare procedures but also as a result of daily gestures involving the gums (chewing and oral hygiene). The risk of presenting a transient bacteremia is related to oral cavity bacterial load and to the severity of inflammation in the oral cavity.

The health risks of transient bacteremia are almost certainly minuscule compared to the health risks associated with tooth decay and gingivitis, and the chances of the average person developing those diseases are much higher if they do not brush and floss. In addition, the amount of inflammation in the mouth (and the bacteria load) is increased by not brushing and flossing since it allows plaques to build up, leading to gingivitis, an inflammation of the gums.

Please don't give out health advice that is contrary to what the mainstream medical community says.

 

[Pythagorean]

Not just sugar, but simple carbs in general. If you white bread and you let it stick to your teeth, it will do a lot of damage over time.

 

[Stavros Kiri]

Are we talking about the net effect of carbs in the blood stream or on the mouth itself? (or both?)

 

[Stavros Kiri]

Are we talking about the net effect of carbs in the blood stream or on the mouth itself? (or both?)

Carb levels can also affect the intestines' microbiome equilibrium (e.g. candida development, or even simple bacteria etc.). I'm not sure though if and how it all starts from the bloodstream and how it affects it etc. . But in any case I think it's much deeper than just "sugar on the mouth" ...

Anyone knows more about these?

Another remark: brushing is not just for bacteria. Also for stain, odour etc.

 

[jim mcnamara]

This link indicates changes in gut microbiota induced by altering dietary fiber amount and type - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5331556/
This is a meta-analysis and no strong conclusion showing x fiber has y result, good association not necessarily causation. Fiber is mostly indigestible carbohydrate, FWIW. This also indicates evidence mapping helps data realization and point to areas for more research: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5331556/

This link shows that lifestyle changes and changes in digestible carbohydrate and to a lesser degree other macronutrients (fats, proteins) does alter gut microbiota. Again areas for more research indicated. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4303825/Also - this stuff is not what the thread is about. Getting back on topic would be great.

 

[Fervent Freyja]

Teeth spacing has a lot to do whether a person develops cavities! The more crowded a tooth is next to another, the higher chance that a cavity will develop in that area.

 

[Stavros Kiri]

This link indicates changes in gut microbiota ...
...
This link shows that lifestyle changes and changes in digestible carbohydrate and to a lesser degree other macronutrients (fats, proteins) does alter gut microbiota.
...

Also - this stuff is not what the thread is about. Getting back on topic would be great.

Thanks for the interesting and useful (in general) references and links. To stay on topic, guts microbiota and microbiome was not directly my main priority here, but rather to answer:

Are we talking about the net effect of carbs in the blood stream or on the mouth itself? (or both?)

and

[Carb levels can also affect the intestines' microbiome equilibrium] ... I'm not sure though if and how it all{i.e. both regarding guts and mouth-teeth + etc.} starts from the bloodstream and how it affects it etc. . But in any case I think it's much deeper than just "sugar on the mouth" ...

which no one really answered.

These are not off-topic, because they try to investigate the deeper causes, regarding to how exactly sugars and carbs consumption relates to tooth decay and other tooth diseases (e.g. gum disease etc.). That relation has been successfully identified by the thread and it seems on the right track.
But the aspects of this relation and the deeper causes may be multiple. Perhaps there's much more to it than just the effect of sugars and carbs (and relative acids) directly on the mouth [although that's certainly one cause and aspect, but is it the main one?]. Involving the bloodstream, and perhaps much less the intestine balance and health, seems reasonable because these are almost directly affected by our nutrition (e.g. by sugars and carbs), and may thereafter affect the whole organism, not just teeth.
Thus my main inquiry was regarding to whether anyone knows more about these, and I think that's within topic. (I plan on doing some research on it myself later on, to find helpful references.)

Because of course teeth are fed (get nutrients) from the blood itself, and futhermore the intestines microbiota balance perhaps may have a feedback effect on the blood (e.g. improper balance could supply the bloodstream with bacteria etc.) ...

Thus, slightly in other words, regarding the original post

Why do humans get cavities if the teeth are not brushed whereas animals like dogs, cats and horses don't have cavities?

it may be that humans get cavities even if teeth are brushed (in the case of high sugars and total carbs diets, etc.) ..., [because teeth are really fed through the blood etc.]

IMO we should really answer those, if we really want to answer this thread adequetly.

 

[Drakkith]

it may be that humans get cavities even if teeth are brushed (in the case of high sugars and total carbs diets, etc.) ..., [because teeth are really fed through the blood etc.]

Tooth enamel contains no blood vessels and is not maintained by the body.

 

[SlowThinker]

Because of course teeth are fed (get nutrients) from the blood itself

Tooth enamel contains no blood vessels and is not maintained by the body.

AFAIK tooth enamel is repaired by saliva.
I've also heard that tooth problems appeared after humans started to grow wheat (not sure about rice etc.) and weren't present before.

A point that hasn't been mentioned yet is that the humans' mouth bacteria might have developed over the past few hundreds of years. Before, if it was too aggressive, the person would just die. Now we survive but the bacteria might be becoming more dangerous over time. Also I'm not sure how much people kissed in say 18th century and before, so the spreading of bad bacteria wasn't very fast.

 

[Drakkith]

This thread is in serious danger of being locked. Further responses should avoid speculation and guessing and should include appropriate references.

 

[Stavros Kiri]

Tooth enamel contains no blood vessels and is not maintained by the body.

True, after the tooth has grown. See e.g. (from Tooth enamel - wikipedia):

"Enamel is the hardest substance in the human body and contains the highest percentage of minerals, [1] 96%, with water and organic material composing the rest.[2] The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate.[3] Enamel is formed on the tooth while the tooth is developing within the gum, before it erupts into the mouth. Once fully formed, it does not contain blood vessels or nerves. Remineralisation of teeth can repair damage to the tooth to a certain degree but damage beyond that cannot be repaired by the body. The maintenance and repair of human tooth enamel is one of the primary concerns of dentistry."

While the tooth is growing, minerals (such as calcium... etc.) have to go into the tooth ... etc.

After a short study that I did, it seems that the dominant main-stream view is that cavities (including internal ones), and even eventually blood vessel and nerve damage (requiring root-canals), are caused by mouth bacteria, which, due to increased carbs/sugars and bad mouth hygiene, convert sugars into acids, causing tooth-corrosion and proceeding through the enamel of the tooth (gradually, after corrosion). So may be we can just leave it as that! (but investigating never hurt anyone). [unless well-supported peer-reviewed evidence is found].

Here is a good valid main-stream review:
[The Five Stages of Tooth Decay - Understanding the Condition]
http://www.zipheal.com/tooth-decay/five-stages-of-tooth-decay/1714

Note: I had almost completed this post before Drakkith's previous one ...

Edit note: Also see (very helpful) "The Causes Of Tooth Decay – What You Might Be Doing Wrong":
http://www.zipheal.com/tooth-decay/the-causes-of-tooth-decay/1779

 

[Fervent Freyja]

Also I'm not sure how much people kissed in say 18th century and before, so the spreading of bad bacteria wasn't very fast.

Kissing is not going to make much of a difference at all in terms of inducing a higher bacterial load of preexisting strains, you will naturally take care of the millions introduced during a session. However, what you do want from kissing is to be introduced to as much variety of microbiota as you can, the more diverse, the better- kissing improves the immune system. Over time, high-frequency kissing with the same person will cause marked changes and improved diversity of a person's oral microbiota. I would also argue that a person has better dental hygiene if they kiss a lot, thence, preventing them from developing fewer cavities. Humans have always "kissed" each other. Spreading bacteria is often more beneficial than dangerous!

 

[Drakkith]

However, what you do want from kissing is to be introduced to as much variety of microbiota as you can, the more diverse, the better- kissing improves the immune system.

I remain a bit skeptical about this. The article says nothing about how a larger variety in oral bacteria improves the immune system.

I would also argue that a person has better dental hygiene if they kiss a lot, thence, preventing them from developing fewer cavities.

How is a larger variety in one's oral microbiota beneficial to dental hygiene?

 

[Pythagorean]

I remain a bit skeptical about this. The article says nothing about how a larger variety in oral bacteria improves the immune system.
How is a larger variety in one's oral microbiota beneficial to dental hygiene?

Part of the Hygiene Hypothesis is that your adaptive immune system learns from exposure. I don't know where HH is at today, but it was buzzing 5 years ago.

 

[symbolipoint]

Nice discussion about bacteria and immunity/immune system.
...

DO WHAT YOUR DENTIST AND HYGIENIST TELL YOU!

 

[Fervent Freyja]

I remain a bit skeptical about this. The article says nothing about how a larger variety in oral bacteria improves the immune system.

How is a larger variety in one's oral microbiota beneficial to dental hygiene?

The second article does. I might add though, it probably depends on the person's health as to whether or not the newly introduced strains are going to be beneficial to the receiver. "Good" bacteria can improve functioning in any location of the body, even oral. It's even been suggested that transplanting "good" digestive bacteria from healthy people could help those suffering from malnutrition and starvation in third world countries.They prevent the growth of bad bacteria and can function with other strains in many beneficial ways.

 

[Drakkith]

The second article does.

Perhaps I missed it, but I didn't see anything in that article that specifically talked about variety being beneficial to oral hygiene, especially in regards to dental caries, which, as far as I know, aren't caused by "bad" bacteria.

 

[Stavros Kiri]

... about variety being beneficial to oral hygiene, especially in regards to dental caries, which, as far as I know, aren't caused by "bad" bacteria.

I agree. The mechanism of tooth decay is simple and specific. Please read [again] the following two quotes:

After a short study that I did, it seems that the dominant main-stream view is that cavities (including internal ones), and even eventually blood vessel and nerve damage (requiring root-canals), are caused by mouth bacteria, which, due to increased carbs/sugars and bad mouth hygiene, convert sugars into acids, causing tooth-corrosion and proceeding through the enamel of the tooth (gradually, after corrosion). So may be we can just leave it as that! ...
...
Here is a good valid main-stream review:
[The Five Stages of Tooth Decay - Understanding the Condition]
http://www.zipheal.com/tooth-decay/five-stages-of-tooth-decay/1714
...
... Also see (very helpful) "The Causes Of Tooth Decay – What You Might Be Doing Wrong":
http://www.zipheal.com/tooth-decay/the-causes-of-tooth-decay/1779

Also, from the first reference (but cf. very similar quote on the second):

"The two chief causes of tooth decay are:

• A diet that’s high in sugars
• Poor dental hygiene

After each meal, food debris clings to the teeth. If this is not brushed away, the bacteria in the mouth transform the sugars in the food debris into acids. These acids then cause a breakdown of the tooth structure. As the stages of tooth decay keep progressing, the infection spreads to nearby teeth as well."

These should avoid or answer your dispute. I am not an expert, but it seems that the bacteria needed for sugars conversion into acids are simple, common and specific (like in fermenting), probably found easily on any mouth or they develop further if mouth hygiene is not met. The main and original cause though is the food debris that get stuck in the teeth (if high in sugars), that's why we should brush our teeth! Simple as that!
Tooth Decay and most related issues of this thread etc. are explained in detail and fairly adequate in the two references that I gave twice earlier above. (They answered most of my questions etc. - Now if science finds something else or more in the future, it's a different story.)
And as also mentioned there (in the sources), consult also your dentist etc.

Thus kissing seems to be irrelevant (but kissing is good!).

how much people kissed

Kissing ... ...

Finally, regarding:

It's even been suggested that transplanting "good" digestive bacteria from healthy people could help those suffering from malnutrition and starvation in third world countries.

We have probiotics for that (even in proper food supplements) ...