Life Science

Why Do We Have Wisdom Teeth?

- asks Rachele Cooper, a scienceline staff member

February 5, 2007
A troublesome tooth. [CREDIT: DR.BUNN.COM]
A troublesome tooth. [CREDIT: DR.BUNN.COM]

Not just a year ago my wisdom was tucked tightly away in my mouth, just below the surface of my gums, bothering no one. And then, last fall, it decided to emerge in the shape of three large, impacted teeth that had to come out. As I lay under the dental surgeon’s tools over the holidays, slowly coming out of my anesthesia, I wondered to myself: where did these teeth come from?

Anthropologists believe wisdom teeth, or the third set of molars, were the evolutionary answer to our ancestor’s early diet of coarse, rough food – like leaves, roots, nuts and meats – which required more chewing power and resulted in excessive wear of the teeth. The modern diet with its softer foods, along with marvels of modern technologies such as forks, spoons and knives, has made the need for wisdom teeth nonexistent. As a result, evolutionary biologists now classify wisdom teeth as vestigial organs, or body parts that have become functionless due to evolution.

Why do wisdom teeth wait to erupt long after the tooth fairy has stopped leaving change under your pillow? Tooth development, from baby primary teeth to permanent teeth, takes place in an organized fashion, over a course of years, with the first molar erupting around the age of six and the second molar erupting around the age of 12. Wisdom teeth, which begin forming around your tenth birthday, are the last set of molars on the tooth-development timeline, so they usually don’t erupt until you are between the ages of 17 and 25. Because this is the age that people are said to become wiser, the set of third molars has been nicknamed “wisdom teeth.”

Some people never get wisdom teeth, but for those who do, the number may be anywhere from one to four – and, on very rare occasions, more than four, according to a study published in the Journal of the Canadian Dental Association. Scientific literature has yet to be able to explain why the number of teeth per individual varies, but for those who do get these extraneous, or supernumerary, teeth, it can lead to all sorts of problems.

Because human jaws have become smaller throughout evolutionary history, when wisdom teeth form they often become impacted, or blocked, by the other teeth around them. Also, if the tooth partially erupts, food can get trapped in the gum tissue surrounding it, which can lead to bacteria growth and, possibly, a serious infection.

Wisdom teeth that do not erupt but remain tucked away can also lead to oral problems, such as crowding or displacement of permanent teeth. On very rare occasions, a cyst (fluid filled sac) can form in the soft tissue surrounding the impacted wisdom tooth. These cysts can lead to bone destruction, jaw expansion, or damage to the surrounding teeth. Even more uncommonly, tumors can develop in the cysts, which can lead to the jaw spontaneously breaking if the tumor or cyst grows too much.

There are patients that develop wisdom teeth that function just as well as every other tooth in the mouth, and as a result they do not need to go under the knife. But no one can predict when third molar complications will occur, and the American Association of Oral and Maxillofacial Surgeons estimates that about 85 percent of wisdom teeth will eventually need to be removed.

If you do have wisdom teeth that you are thinking of having taken out, the association strongly recommends that patients remove wisdom teeth when they are young adults, in order to “prevent future problems and to ensure optimal healing.” People who have oral surgery after the age of 35 have higher risks for complications, harder surgeries, and longer healing times than those who get them removed in their late teens or early 20’s. The best time to get those suckers out is when the roots are about two-thirds formed, which is generally between the ages of 15 to 18. Though I was…well, a lady never tells her age, but suffice it to say that for me, a weeks long lack of locution and a diet of soup and applesauce was worth no longer having pain in my jaw and food in my teeth.


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Nkrumah Ming says:

I am 47 and a black guy, (i include my racial identity as I am told that black people tend to have very strong teeth which has some bearing on my story)

The dentist I went to this mornng told me that I have very good teeth , this despite the fact that I brush only once or twice per week.

Anyway have all my teeth except 1 lower jaw wisdom tooth which came out about 2 hours ago.

This is the saga, my wisdom teeth appeared between the ages of 29 and 34 and it was virtually painless, unfortunately the wisdom tooth that just exited the building was shaped slightly like a deep cup and after years of my very bad brushing practice (sometimes not brushing for a month or more) the food trapped in the cup eventually caused a severe cavity, when because of the pain I had no options left I went to the dentist, a filling was put in, three months later was in extreme pain as the filling was pressing on the nerve, because of the pain I had no options left and went to the dentist asking to have it taken out, they injected sawed hacked drilled and cracked the tooth in half then injected sawed hacked drilled some more, for maybe two hours, eventually a second dentist was called in, he was a hefty six footer, he put pliers in my mouth and his knee against my chest and tried his best to convince the tooth to come out… it did not want to know(has such a love a tooth ever known for a mouth ?) nedless to say the pain was absolutey exquisite!

Anyway they gave up and left the shards of this unremitting tooth in my mouth, try to imagine a beer glass shattered stuck firmly in the back of ones jaw. Anyhoo , that was two years ago, today I went in to get the shards removed as my tongue was still being lacerated by the sharp edges (which in most cases should have rotted away which is what i think the dentist expected to happen). Anyway this time it only took only 10 minutes and the tooth was out, two hours later I can report the pain is minimal, courtesy possibly of 3 aspirin, and the bleeding is finished.

I have three pieces of advice:
1:If your wisdom teeth are not a problem leave them in.
2:If your dentist says you need a filling, and you know you have strong teeth, don’t get that filling straight away, brush your teeth properly for a month or so then see if you still need the filling. What dentists do not tell you is that teeth can repair themselves to some degree. At least 4 times a dentist has told me I need a filling and I applied the above advice and the problem completely disappeared.

3: Even if you have strong teeth, beleive in PREVENTATIVE MAINTENANCE! Brush a lot better than I do :)

Paige says:

Hello. I enjoyed reading this very much. I am 17 years old and I have four wisdom teeth that have stopped growing. Well, the two top ones I think are fully grown.. they aren’t as big as my normal molars so I’m not sure.. though no gum tissue is covering the top ones. I have two bottom ones that I think are half way grown, half way still in my gum tissue. There is NO room for those two bottom ones to go, I have had crowding in my bottom row thats been fixed, but no teeth were removed and still no room for more. However… at the state these teeth are in.. well.. its been this way for about five years already. Yes, they seemed to have grown in even before my 10th birthday. The strange thing is, I have never experienced any pain from these teeth so naturally I ignored it. My dentist never says anything about them, but he doesn’t know how long they have been like this. They have not grown in five years… no pain at all.. not to get my hopes up, but maybe I could be a lucky person who doesn’t need them removed? ;) My two top ones function as normal teeth to me now, and my bottom ones never hurt, and no food has ever gotten in my gums, they are tightly packed. They have never been inflamed either… so, can anyone give an opinion here? I plan to talk to my dentist next time I go though.

Joel says:

A very good arguement to support evolution. Makes more sense than a creator giving us random teeth that dont even fit. Perfect creation my ass :)

Niggas says:

Fuck all this shit, nasty ass pussy

Taylor says:

I was just wondering this and asking my dad why we have wisdom teeth. I really enjoyed this.


I have pain in my wisdom tooth,which begin to grow from today.I LUV having all this. RAJA OVIAS BHAT KASHMIR.

Greg says:

I always was taught if there is no pain, leave them alone. So I never had my bottom ones removed. Unfortunately they were impacted. They became more impacted in my 40’s and a caused an infection, causing me to have not only the wisdom tooth removed, but I lost my back molar as well. Now, I’m hoping my jaw bone heals enough that I can get an implant. Get rid of them. It’s not worth the chance of loosing your other teeth because of them.

Saeed says:

Hi there! Excellent article. Though I am a bit scared now, I find it very informative.keep up the good work.
cheers to everyone.

Megan says:

To those who say that wisdom teeth are “necessary”….why would so many people have them removed if they existed for good reason? Simply put, our jaws are becoming smaller and these teeth have not yet disappeared via evolution. They are not useful unless a person dines on roots and tough meat for each and every meal.

Anonymous says:

Well now this article clear the confusion, I will go ahead and get my wisdom teeth removed. Was afraid removing it will also remove whatever wisdom I had left :-)

I am 37 y.o. Since last couple of days had terrible pain, my dentist has been telling me to remove these for (at least) last 5 years. I have been avoiding since it was not hurting and it involves a “surgery”. Many of my friends I have talked to haven’t removed theirs either.

Saranda says:

Yeah, I’m getting mine taken out tomorrow and I’m only 15, but in my biology accelerated class, there was a lot of talk about how we’ve started to “mutate”, and not like x-men but there are many people that are starting to not even have them because there is no use for them and since they cause sists and cancer, I was like, take them out now!! Ha-ha. But i like this article, very interesting! I’m kind of nervous of tomorrow!!!

Its like you read my thoughts! You appear to understand a lot about this, like you wrote the book in it or something. I feel that you could do with some percent to force the message house a bit, but instead of that, this is fantastic blog. An excellent read. I will certainly be back.

edward says:

i am havin mine as we speak and the pain is unbearable .i cant satnd it no more,

kyabeth says:

ummm but im 12 and my wisdom teeth are growing now i can see the little hole is this common ?

briey says:

my names briey and im almost 16 i have never had a cavity or had to get a tooth removed . im a little scared … my wisdom tooth is growing in … the one on the back right. i was just wondering if i should get it tooken out or if i should wait till all of them grow … its been really painful and hard to eat … any sugestions ?!??

brian says:

I have epilepsy and I will have a seizure when I get mine removed because I can’t get a simply shot with out having a seizure. So what am I going to do about these pointless teeth?

Mary Jane says:

Hello my former comment goers,
I would just like to inform everybody that my wisdom teeth has not come in yet. Neither has my friend Gabby’s. We are seriosuly concerened that we are abnormal. Is there any foods, or vitamins we can take to get them to grow?? We eat really hard roots, and plants so we really need those extra four teeth to help us out.
If you have any advice please let us know ASAP!!!!!!
Thanks :)

neetalia says:

Tomorrow I am taking my child for tooth extraction. What things I should take care off so that he doesn’t freak out?

Yahn :) says:

Interesting. I thought only small women like me that have little facial structure get the problem of supernumerary wisdom teeth; it’s actually a worldwide concern. Maybe the next generation of kids won’t have these teeth any longer. Just maybe in the near future.

Lauren says:

Hi everyone! I am 16 and will be a junior this fall. I play tennis monday through friday 3 and a half hours a day in the summer and play tournaments. Also have been doing drivers ed and AP US History HW this summer. Yesterday I had all 4 of my wisdom teeth removed. None of them had surfaced the gums. So, i thought i would explain my experiences since i like whomever is reading this right seems to be slightly or extremely nervous like i was before. SO ANYWAYS here is my story. OK so I have never had a surgery before this so I was kind of nervous. The worst pain i have ever experienced was dislocating my kneecap is sixth grade and the worst dental experience I have had was removal of like four teeth before getting braces. My situation with my wisdom teeth was pretty good. I had no impacted teeth, praise God:), and since i’m a teen my roots weren’t too deep and hooked if you know what i mean. So yesterday an hour before my surgery I had to put under my tongue a pill that dissolved which made me kind of loopy. Once we got to the oral surgeon I played peek a boo with a baby in the waiting room and like five minutes latter was called back. Go time. I made my way into a small room and was seated into your average dentist chair. Following being seated, I blood pressure cuff was placed around my arm. After this, she put three stickers on my chest: two up high near my collar bone, and one on the side of my rib cage bellow my uh… boobs. gasp! haha no big deal:) After that, the oral surgeon came in and gave me an IV. I have never had an IV before, but last year I had my blood drawn because my doctor thought I had mono.. i didn’t. Anyways the IV everyone gets all worked up about the IV please take it from the biggest baby in the world it DOES NOT HURT AT ALL AND IS NOOOOOO BIG DEAL. Just look away and you will be fine. Following my IV they strapped that arm to the chair so that during my surgery i would not more it. OH ALMOST FORGOT they put an oxygen thing over my nose. So here is the lovely thing about modern day medicine I was talking an all of a sudden somewhere in the conversation i went out like a light bulb. I don’t even remember falling to sleep. But I did:) Then about an hour or hour in fifteen minutes I wake up and was like wow I did not remember going to sleep! haha! All the stuff the IV, blood pressure cuff, heart monitor stickers, and oxgen mask had been taken off. The lady that had put the stickers and stuff on me placed a blanket on me she said the IV makes you chilly and trust me it does. I had goose bumps. About three minutes latter she said my mom was pulling around to an exit door and she assisted me to our SUV. Most of my mouth, chin, cheeks, and even part of my ears were numb. Honestly the pain for me at least was and has been a day latter very minimal. I personally think my braces hurt my teeth more than this. I have been livin it up at home chowing down hahaha NOT CHOWING DOWN on pudding, jello, and shakes. The only thing that’s annoying is the stitches and not being able to eat solid foods. I learned from friends that they tried eating bagels and ended up with dry socket so yeah i do not even want to attempt that. I’m not getting dry socket. OK but here is what I recommend to you all.
1. Before your surgery have all the food you want to eat like jello and pudding made or bought
2. Get your laptop connected to a charger next to wherever you are laying down when you get home as well as iPhone charger or what ever technology chargers were you will rest.
3. Get pillow and blankets ready

By the way like all of yesterday i had gauze in my mouth

Twist says:

Well yahoo I am the very rare sob. I have a total of 6 wisdom teeth in my mouth and am enjoying the agony of the post-op removal of two under the gumline (two more on the other side)

Polly says:

I have 4 wisdom teeth, yet they don’t affect me. They’re tucked away wayyyy in the back.

Ranu says:

I am 30 year old now a days my 4th wisdome teeth is coming out its so painful. I am taking painkiller and anibiotics. Now I am confuse what to do remove all these teeth or not . :(

Anonymous says:

I am 45 and was lucky enough to only ave one wisdom tooth. (lower right). Was advised for years to have it removed, but like many others I took the position of “if it ain’t broke, don’t fix it.”

Started noticing some bumps on my gum line a few months ago, and about two weeks go the corner of the tooth erupted. Don’t know why it suddenly decided to erupt, but didn’t have any aggravating dental problems.

Anyways, went to the dentist and had an x-ray and the tooth was slightly impacted against a fron molar. Dentist suggested removing it so that it would not effect the healthy molar.

Happy to say I had the tooth pulled today under local anesthetic. It took longer for the tooth to numb then he extraction process. NO PAIN whatsoever, and was back at work within an hour. Ate a light lunch of soup, and really only have a littl discomfort due to the injection site. No swelling, a little soreness, and probably more discomfort due to the stitches.

All in all I’m glad I did it. Should have done it at 19, but just wanted to let those over 20 know that you can do it, and at least this is one story of a 45 yr old with no complications.

I would recommend removal in your early years. The dentist I’d warn me that it could have been difficult due to the maturity o the tooth.

By the way, the tooth was in perfect condition, no decay. But I was worried that the partial eruption could have led to decay below the gum, and also possible endangered the molar in front.

teea says:

I’m 19 and I think I mine are just growing out…. They REALLY hurt… But I’ve actually never been to a dentist so I’m nt sure if I will. My face is all swollen! I am NOT enjoying it. I could nt sleep last night and I don’t kno if I will this. What do I do?!

Courtney says:

I’m almost 16 so…..yeah mine are about to come out right now….I just had to leave school early today b/c of the excruciating pain in my gum….and when I went to the dentist, they said that it was my wisdom teeth coming in! Omg…..I am so nervous about the surgery…..I’ve had surgery before…..but still……………HEY! At least I’ll miss a couple days of school and eat Popsicles and stuff… friend told me everything about this today during lunch……lol I could barely eat my lunch….xD Waste of food…..but oh well…’s life. Stuff happens. :)

Greta says:

I had my second molar removed yesterday because my wisdom tooth has grown into it, and broke it. I had choose to either have a surgery and remove the wisdom tooth, leaving the second molar and trying to save it with canal root treatment, or removing the impacted molar and allow the ‘ninja’ wisdom tooth to grow into its place… After discussing it with several dentists I finally got my molar removed, because they predicted that the molar would not last me more than few years, it was that badly damaged. I just hope that I made a right choice and the wisdom tooth will grow in nicely without much more complications. The pain was horrible…

HI, Very intersting article. Reason why I am posting this is because I have not had my wisdom teeth…ANY! and I am in my sixties. Dental X-rays do not show any sign of any budding roots or anythying for that matter.

So, having read an article on evolution and Wisdom Teeth does this means that I am one step ahead. I am one of eleven children and I am the only one with no WISDOM TEETH. My parents had them too, and so have my children.

Can anyone explain this mystery please.

James says:

Recovering after removal of bottom right WT. I feel a new man! Dentists have told me that that there was no need to remove it unless it was giving me serious problems as it was very impacted with deep roots and I’m in my 40s. For the last 6 months I have been getting infections with swelling and pus and finally decided to go for the root cause and get the ‘devil tooth’ removed. The surgeon said that I should have had it removed a long time ago – turns out there was a bad cyst and a benign tumour which was also cut out. 48 hours later a little sore but not much swelling. It does seem from the forum that bottom WTs give the most problem. Had left side out 5 yrs ago but top ones seem fine. The only problem is that because of the antibiotics I can’t have a drink on my birthday tonight.

Ness says:

I have just got my first wisdom tooth at age 43!!
Went to dentist who took an x-ray he said I only
had the two on the left and that the top one has come
through fine, so I am lucky. Lower is impacted
so just have to wait and see with that one! After reading the above I hope it stays put!!!

Braden says:

I’m 17 and I just recently had all 4 wisdom teeth removed. My bottom two had already been in for almost 2 years and my top two were just starting to erupt. My wisdom teeth were not overly large and there was plenty of room for them in my mouth but my dentist insisted they needed to come out. I tried to convince my mom that they didn’t need to come out and that my dentist only was using this as an excuse to make some money. Needless to say, I lost this little disagrement and had the great opportunity of getting four teeth forcefully ripped out of my jaw. I was just given some novocaine so I was awake the whole time. It only took
about 30 minutes to take them out so it was really pretty easy. The dentist had to break one of by bottom teeth in two pieces to get it out but that was the worst of my experience. I didn’t even take any pain meds the day I got them out so I feel pretty lucky. I wish that I still had those teeth though. Now that my mouth is all healed up I just have a bunch of wasted space in the back of my mouth. So I’ll probably have a grudge against my dentist for a little while but I’ll get over it. I just liked the fact that I essentially had an extra set of molars. But oh well, after reading some of these other comments I just feel lucky that my four teeth were in straight and not impacted or anything. So my opinion is if they’re going to be a problem or causing you pain then get them out, but if they’re just fine then tell your dentist to shove it and that you’re keeping your wisdom teeth…haha

Lucia says:

Im kinda nervous because I’m 22 and my wisdom tooth is coming out. It really hurts, but I am afraid of surgery.. I don’t know what to do.. I didnt want that happen to me…

AnDaiya Reynolds says:

I had some removed back in October and I had the blues, but I wasn’t in much pain period I was 18 at the time and this past Friday (now 19) I had my last two removed and yes I was awake on both exaction, but the second one didn’t have much pain and I didn’t have to take my medicine as much and when I regained the normal feeling in my mouth I wasn’t in much pain and I’m recovering very fast (it’s day four after the exaction) other than that this article provides useful information

William says:

Wisdom teeth don’t come in straight because the jaw does not grow to it’s full potential due to our nutritionally deficient modern diets. Weston Price documented this in his work “Nutrition and Physical Degeneration” ( freely viewable on Gutenberg ).

Niharika Singh says:

Awesome… You have ever explained well … Even in wikipedia info is lacking..
Can I eat trident chewing gums ?? I am 17 years old an wisdom teeth are now poping in my mouth.. Very painfull …

Jenna says:

i suggest getting them taken out. i am eighteen years old and about a montha go i had mine cut out cause they were impacted.

the only problem i am having right now is infection from food getting stuck in the sockets, which my dentist says is normal for anyone whose had they’re teeth cut out.

was i in pain? heck yeah! for about a week i couldn’t talk and had to refrain from eating my fave foods but from everything my dentist told me about the problems wisom teeth can cause, i’d say take them out. it is worth it!

jordan says:

i am 14 and all four of mine have “erupted” perfect (i hope)

Paul says:

I still have all my wisdom teeth at age 58 (59 in July 2013). About 4 years ago
I noticed another tooth coming through the gum behind the left upper wisdom tooth. Today the gum has a lump and is sore next to the newest tooth, so I suspect it is part of the new wisdom tooth. Perhaps time to see the dentist again.

Ben says:

eww that creepily me out with the cyst

Ben says:

cyst creeped me out

Emma says:

I’m 11 almost 12 and my wisdom teeth r starting to come in and it hurts around my gums when my tounge touches it.

sirisha says:

I have wisdom teeth. They are grown unevenly and the pain was horrible that i can’t eat any thing. If i tried to have some food it got got stucked in to the that. When i consult to doctor he suggested to take out the tooth i was very afraid to take out the tooth, But when the treatment has got started everything was normal and i’m felling better after the treatment.

viksha says:

I’m 14 and a wisdom tooth is growing,pretty weird

Jason says:

My top left wisdom tooth started to pop out just less than 24 hours ago. Actually yesterday I was completely fine, able to eat, talk and socialise normally. But then just last night I woke up at the middle of my sleep and felt a sudden swelling in my lower left gums.

It turns out that my top left wisdom tooth is biting down on my bottom left gum which is now bloated/swollen. I still decided to go to school today despite it being a Friday and being a the day for the semester/term. BIG MISTAKE…. Bit down on my lunchtime sandwich and suddenly the pain was barely tolerable. I managed to keep my cool for the whole day but man! It hurts..

And this is coming form a guy whose had a circumcision lol. I don’t think it’s the magnitude of the pain itself but instead it’s persistence. I could stand the pain itself but the fact that it is continuous is what really gives it its BANG, If you know what I mean.

Anyway I ended up asking one of my teachers for painkillers. She gave me 4 neuromol pills. Kind lady she is. The painkiller didnt really do anything until about 40 mins of taking it. And it seems that the effect is wears off about 5 and a half hours.

This whole debacle is just an amazing bad timing. I have a school prom tomorrow night. What the hell am I supposed to do if I can barely talk, eat and socialise properly.

Actually my speech is only a little impeded but I can pretty much talk as clearly as before… I think.

In other matters, currently I have 1″erupted” top left WT. while the three others are partially erupted. All are coming out straight and they don’t seem to be coming out at an angle I hope….

Rhoadie says:

I am about to get one of my impacted wisdom teeth taken out this morning. I am 32 and I had 4 molars taken out when I was a teen and needed braces. At the time my dentist said that my wisdom teeth shouldn’t bother me and just to keep an eye on the impacted one (lower right) if it does not straighten out on it’s on. I had not had any problems with it until this past Sat. At first it started out with a slight pain, but yesterday morning I woke up with the worse pain ever. Feels like someone has stabbed my jaw. Cannot wait to get it removed today.

Laura says:

Ugh, my doc wants me to get mine out. I def fear it because I have an irregular heart beat at times. And one time even some local made my heart beat crazy. I’m 23 and I know I sound like a kid haha but….it freaks me out. I dont have the money to have it done right now (broke college kid) but it scares me!!! My jaw has been acting up and I fear its WT… I have 4…

AssA9 says:

I am 30 I have 6 wisdom teeth and they are quite nice sure they hurt a little when coming in but so did the rest of my teeth when I was little. My jaw is large enough that they all fit fine and they didn’t actually start coming in until my mid twenties. I am quite happy with them and will not ever have them removed!

Austin says:

So I decided before I turned 29 I will kindly remove my wisdom teeth. I made the mistake of inquiring with friends and family over their experiences (big mistake). Everyone’s pain tolerence and experience is very different. For the most part everyone had something horrifying and traumatizing to say. I then ventured out to you tube and watch the process take place (2nd big mistake).
Really turned off by what I saw. Either way I knew that even though my wisdoms weren’t causing any uncomfort i wanted them out!!! So I put on my big boy pants on, called my dentist and made my appointment. A week later I was being escorted to THE chair, no doubt I was nervous and eager to get this process over with, I would say the most painful part was getting numbed. After dealing through the uncomfortable needle stabbing to get my mouth completely numb, I closed my eyes, turned up my Dido and let them go to town. Ten minutes later my beautiful Dentist grabs my face and notifys me that they are done, I swear that was a drive by! The crazy thing is that I was at my salon working on clients and laughing about my experience the next day! Based on a true story!!!!

Cara says:

I have all 4 well aligned wisdom teeth, which came in without problems. The dentists have never suggested removing them, and I actually have a crown on one of them to keep it healthy. I am in my late 50s and have had no problems at all with them. My parents both had theirs and my children have 4 functioning wisdom teeth as well. It seems odd to read these horror stories.

Janvi says:

I m 17 years old and I have 32 teeth? Is it normal?

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