What causes cavities Mel Rosenberg

When a team of archaeologists
recently came across

some 15,000 year-old human remains,

they made an interesting discovery.

The teeth of those ancient humans
were riddled with holes.

Their cavities were caused by the same
thing that still plagues us today,

specific tiny microbes
that live in our mouths.

These microbes are with us
soon after birth.

We typically pick them up as babies
from our mothers' mouths.

And as our teeth erupt,

they naturally begin to accumulate
communities of bacteria.

Depending on what we eat,

and specifically how much sugar
we consume,

certain microbes can overpopulate
and cause cavities.

Diets high in sugary foods cause
an explosion of bacteria

called mutans streptococci
in our mouths.

Like humans, these microorganisms
love sugar,

using it as a molecular building block
and energy source.

As they consume it,

the bacteria generate byproducts
in the form of acids,

such as lactic acid.

Mutans streptococci are resistant
to this acid,

but unfortunately, our teeth aren’t.

While each human tooth is coated
in a hardy, protective layer of enamel,

it’s no match for acid.

That degrades the armor over time,
leaching away its calcium minerals.

Gradually, acid wears down a pathway
for bacteria

into the tooth’s secondary layer
called the dentin.

Since blood vessels and nerves
in our teeth are enclosed deep within,

at this stage, the expanding cavity
doesn’t hurt.

But if the damage extends
beyond the dentin,

the bacterial invasion progresses

causing excruciating pain
as the nerves become exposed.

Without treatment, the whole tooth
may become infected

and require removal

all due to those sugar-loving bacteria.

The more sugar our food contains,

the more our teeth are put at risk.

Those cavemen would hardly
have indulged in sugary treats, however,

so what caused their cavities?

In meat-heavy diets, there would have
been a low-risk of cavities developing

because lean meat
contains very little sugar,

but that’s not all our early human
ancestors ate.

Cavemen would also have consumed
root vegetables, nuts, and grains,

all of which contain carbohydrates.

When exposed to enzymes in the saliva,

carbohydrates get broken down
into simpler sugars,

which can become the fodder
for those ravenous mouth bacteria.

So while ancient humans did eat
less sugar compared to us,

their teeth were still exposed to sugars.

That doesn’t mean they were unable
to treat their cavities, though.

Archaeological remains show that
about 14,000 years ago,

humans were already using sharpened flint
to remove bits of rotten teeth.

Ancient humans even made
rudimentary drills

to smooth out the rough holes left behind

and beeswax to plug cavities,
like modern-day fillings.

Today, we have much more sophisticated
techniques and tools,

which is fortunate because we also need
to contend with our more damaging,

sugar-guzzling ways.

After the Industrial Revolution,
the human incidence of cavities surged

because suddenly
we had technological advances

that made refined sugar cheaper
and accessible.

Today, an incredible 92% of American
adults have had cavities in their teeth.

Some people are more susceptible
to cavities due to genes

that may cause certain weaknesses,
like softer enamel,

but for most, high sugar consumption
is to blame.

However, we have developed other ways
of minimizing cavities

besides reducing our intake of sugar
and starch.

In most toothpastes
and many water supplies,

we use tiny amounts of fluoride.

That strengthens teeth and encourages
the growth of enamel crystals

that build up a tooth’s defenses
against acid.

When cavities do develop,

we use tooth fillings to fill
and close off the infected area,

preventing them from getting worse.

The best way to avoid a cavity
is still cutting down on sugar intake

and practicing good oral hygiene

to get rid of the bacteria
and their food sources.

That includes regular tooth brushing,

flossing,

and avoiding sugary,

starchy,

and sticky foods that cling to your teeth
between meals.

Gradually, the population of sugar-loving
microbes in your mouth will decline.

Unlike the cavemen of yesteryear,

today we have the knowledge required
to avert a cavity calamity.

We just need to use it.

当一组考古学家
最近发现了

大约 15,000 年前的人类遗骸时,

他们有了一个有趣的发现。

那些古人类的牙齿
上布满了孔洞。

它们的蛀牙是由
今天仍然困扰我们的同一件事引起的,

即生活在我们嘴里的特定微小微生物。

这些微生物在我们
出生后不久就与我们同在。

我们通常从母亲的嘴里把它们当婴儿捡起来

随着我们的牙齿长出,

它们自然会开始积累
细菌群落。

根据我们吃的东西

,特别是
我们消耗的糖分,

某些微生物会过度繁殖
并导致蛀牙。

高糖食物的饮食会

导致我们口腔中称为变形链球菌的细菌爆炸。

像人类一样,这些微生物
喜欢糖,

将其用作分子构件
和能源。

当它们消耗它时

,细菌会
以酸的形式产生副产物,

例如乳酸。

变形链球菌
对这种酸有抵抗力,

但不幸的是,我们的牙齿没有。

虽然每颗人类的牙齿都涂
有一层坚硬的牙釉质保护层,

但它无法与酸相媲美。

随着时间的推移,这会使盔甲退化,从而
浸出其中的钙矿物质。

渐渐地,酸会破坏
细菌

进入牙齿第二层(
称为牙本质)的途径。

由于
我们牙齿中的血管和神经被深深地包裹在里面,

在这个阶段,扩大的蛀牙
不会受到伤害。

但是,如果损伤
超出牙本质

,细菌侵入会

随着神经暴露而导致剧烈疼痛。

如果不进行治疗,整个牙齿
可能会被感染,

并且

由于这些嗜糖细菌而需要拔除。

我们食物中的糖分

越多,我们的牙齿就越容易受到威胁。 然而,

那些穴居人几乎
不会沉迷于含糖的食物,

那么是什么导致了他们的蛀牙呢?

在重肉的饮食中,
蛀牙的风险很低,

因为瘦肉
中的糖分很少,

但这并不是我们早期人类
祖先吃的全部。

穴居人也会食用
根茎类蔬菜、坚果和谷物,

所有这些都含有碳水化合物。

当暴露于唾液中的酶时,

碳水化合物会分解
成更简单的糖,

这些糖可以
成为那些贪婪的口腔细菌的饲料。

因此,虽然古代人类确实
比我们吃的糖少,但

他们的牙齿仍然暴露在糖中。

不过,这并不意味着他们
无法治疗蛀牙。

考古遗迹表明,
大约 14,000 年前,

人类已经在使用锋利的燧石
来去除腐烂的牙齿碎片。

古代人类甚至制作了
基本的钻头

来磨平留下的粗糙孔洞,

并用蜂蜡堵塞蛀牙,
就像现代填充物一样。

今天,我们拥有更复杂的
技术和工具,

这是幸运的,因为我们还需要
应对更具破坏性、

消耗糖分的方式。

工业革命之后
,人类蛀牙的发病率激增,

因为突然间
我们有了技术进步

,使精制糖变得更便宜
、更容易获得。

今天,令人难以置信的 92% 的美国
成年人的牙齿上有蛀牙。

由于

可能导致某些弱点的基因(
例如较软的牙釉质),有些人更容易患蛀牙,

但对大多数人来说,高糖摄入
是罪魁祸首。

然而,除了减少糖和淀粉的摄入量外,我们还开发了其他
减少蛀牙的方法

在大多数牙膏
和许多供水中,

我们使用微量的氟化物。

这可以强化牙齿并
促进牙釉质晶体的生长,

从而增强牙齿对酸的防御能力

当蛀牙确实出现时,

我们会使用牙齿填充物来填充
和封闭受感染的区域,以

防止它们变得更糟。

避免蛀牙的最佳方法
仍然是减少糖的摄入量

并保持良好的口腔卫生

以消除细菌
及其食物来源。

这包括定期刷牙、使用

牙线,

以及避免在两餐

之间粘在牙齿上的含糖、淀粉和粘性食物

渐渐地,
你嘴里的嗜糖微生物的数量会减少。

与过去的穴居人不同,

今天我们拥有
避免空洞灾难所需的知识。

我们只需要使用它。