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.
Saat satu tim Arkeologi menemukan tulang manusia berumur 15.000 tahun belum lama ini, mereka mendapatkan temuan menarik. Gigi manusia purba itu penuh dengan lubang. Lubang itu disebabkan oleh hal yang sama dengan yang kita alami hari ini, yaitu mikroba kecil tertentu yang hidup di mulut kita. Mikroba ini sudah ada begitu kita lahir. Kita biasanya tertular mikroba tersebut saat bayi, lewat mulut ibu kita. Dan ketika gigi kita tumbuh, mereka secara alami mulai menghimpun sekumpulan bakteri. Tergantung makanan kita, khususnya berapa banyak gula yang kita konsumsi, mikroba tertentu bisa terlalu banyak dan menyebabkan gigi berlubang. Mengonsumsi banyak makanan manis menyebabkan lonjakan bakteri yang disebut streptococcus mutans dalam mulut kita. Seperti manusia, mikroorganisme ini sangat suka gula, memakainya sebagai blok bangunan molekuler dan sumber energi. Saat mengonsumsi gula, bakteri menghasilkan produk sampingan dalam bentuk asam, seperti asam laktat. Streptococcus mutans kebal dengan asam jenis ini, tapi sayangnya, gigi kita tidak kebal. Meski tiap gigi manusia dilapisi lapisan pelindung enamel yang kuat, itu bukan tandingan asam. Asam merusak lapisan seiring waktu, melepaskan mineral kalsium. Sedikit demi sedikit, asam membuka jalan untuk bakteri menuju lapisan kedua gigi yang disebut dentin. Karena pembuluh darah dan syaraf ada jauh di bagian dalam gigi kita, pada tahap ini, lubang yang meluas tidak terasa sakit. Tapi jika lubang meluas sampai bawah dentin, invasi bakteri bertambah menyebabkan sakit yang menyiksa karena syaraf gigi terekspos. Tanpa pengobatan, semua gigi mungkin terinfeksi dan butuh dicabut semua karena bakteri penyuka gula itu. Semakin banyak gula dalam makanan kita, semakin berisiko nasib gigi kita. Manusia purba tidak mungkin makan banyak jajanan bergula, jadi apa penyebab gigi mereka berlubang? Dalam pola makan padat daging, risiko gigi berlubang akan rendah karena daging tanpa lemak mengandung kadar gula yang sangat kecil, tapi bukan itu saja yang dimakan manusia purba. Manusia purba juga memakan umbi-umbian, kacang, dan gandum, dan semua itu mengandung karbohidrat. Saat bertemu dengan enzim di air liur, karbohidrat terpecah menjadi gula sederhana, yang bisa menjadi makanan bagi bakteri mulut yang rakus sekali. Jadi meskipun manusia purba makan sedikit gula dibanding kita, gigi mereka tetap terkena gula. Itu bukan berarti mereka tidak bisa mengobati gigi berlubang. Peninggalan arkeologis menunjukkan bahwa sekitar 14.000 tahun lalu, manusia sudah menggunakan batu tajam untuk mencabut bagian gigi yang busuk. Manusia purba bahkan membuat bor sederhana untuk menghaluskan lubang yang tertinggal dan lilin lebah untuk menambal lubang, seperti tambalan modern. Hari ini, kita punya sangat banyak teknik dan alat canggih, yang menguntungkan karena kita juga harus melawan gaya hidup yang lebih merusak dan penuh gula. Setelah Revolusi Industri, serangan gigi berlubang melonjak karena tiba-tiba ada kemajuan teknologi yang membuat gula halus lebih murah dan mudah didapatkan. Kini 92% orang dewasa Amerika pernah mengalami gigi berlubang. Beberapa orang rentan terjangkit gigi berlubang karena gen yang bisa membuat kelemahan tertentu, misal enamel lebih lunak, tapi mayoritas penyebabnya adalah konsumsi gula tinggi. Namun, kita mengembangkan cara lain untuk meminimalkan gigi berlubang selain mengurangi asupan gula dan tepung. Dalam mayoritas pasta gigi, dan banyak sumber air, kita menggunakan sedikit fluoride. Itu menguatkan gigi dan mendorong pertumbuhan kristal enamel yang membentuk pertahanan gigi melawan asam. Saat lubang berkembang, kita menggunakan isian gigi untuk mengisi dan menutup area yang terinfeksi, mencegahnya bertambah buruk. Cara terbaik menghindari gigi berlubang adalah mengurangi asupan gula dan merawat gigi higienis dengan baik untuk menyingkirkan bakteri dan makanan mereka. Itu termasuk rajin menyikat gigi, pembersihan benang, menghindari yang manis, bertepung, dan kudapan yang lengket di gigi. Sedikit demi sedikit, populasi mikroba pecinta-gula dalam mulut Anda akan lenyap. Tak seperti manusia purba dulu, kini kita punya pengetahuan yang dibutuhkan untuk mencegah gigi berlubang. Kita hanya perlu menggunakannya.