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Pit Bulls : Behind The Jaws



The jaws of a Pit Bull strikes fear into the hearts of many that do not understand these dogs. When looking at pit bull type dogs including breeds such as the American Pit Bull Terrier, Bull Terrier, American Staffordshire Terrier, American Staffordshire Bull Terrier and American Bulldogs, you can easily see that these dogs have strong powerful jaw muscles. This does not however mean that they have an ability or mechanism that allows them to lock their jaws; which is the most popular myth surrounding these dogs. Other common myths about a Pit Bulls jaws state that they have 1600 P.S.I in jaw pressure and that they grip with their front teeth while chewing with their back teeth at the same time. Myths such as these lead people to believe that these dogs are monsters.

Pit Bull Skull

Pit Bull Skull

Labrador Retriever Skull

Labrador Retriever Skull

Poodle Skull

Poodle Skull

Beagle Skull

Beagle Skull

German Shepherd Skull

German Shepherd Skull

French Bulldog Skull

French Bulldog Skull

Australian Shepherd Skull

Australian Shepherd Skull

Airedale Terrier Skull

Airedale Terrier Skull

Dachshund Skull

Dachshund Skull

Chihuahua Skull

Chihuahua Skull

Boxer Skull

Boxer Skull

Cocker Spaniel Skull

Cocker Spaniel Skull


All myths surrounding a Pit Bulls jaws are false and are ridiculous. A Pit Bull's jaw structure is no different that that of any other breed of dog."The few studies which have been conducted of the structure of the skulls, mandibles and teeth of Pit Bulls show that, in proportion to their size, their jaw structure and thus its inferred functional morphology, is no different than that of any [other] breed of dog. There is absolutely not evidence for the existence of any kind of 'locking mechanism' unique to the structure of the jaw and/or teeth of the American Pit Bull Terrier", says Dr. I. Lerh Brisbin of the University of Georgia. Let's think about this logically for a moment shall we. If a Pit Bull or any dog for that matter had a locking jaw how would the dog be able to eat? If a dog's jaw is locked onto another animal how is it that the dog is able to ever let go? Doesn't quite seem reasonable to me. If a dog can voluntarily "lock" it's jaw it's no different from a human "locking" it's jaws on something, all it means is that the muscles are contracted to keep the mouth shut, but it is not locked. Pit Bulls were breed to control unruly cattle and large game such as boars. If the dog were to let go of the bull they could be killed and so could their owner. They same goes for a wild boar, if the dog were to let go as the hunter was approaching the boar would inflict serious and even fatal wounds upon the dog and the hunter. Pit Bulls have the will and determination to not let go no matter the circumstance, they do not lock upon their target. This determination and powerful jaw muscles is where the locking myth gets it's start. Pit Bulls and dogs that are trained for schutzhund (guarding/bite work) must let go on command, if the jaws were locked this would be impossible. Even this strong determination to hold on doesn't mean that they have a stronger bite than any other breed. "To the best of our knowledge, there are no published scientific studies that would allow any meaningful comparison to be made of the biting power of various breeds of dogs. There are, moreover, compelling technical reasons why such data describing biting power in terms of 'pounds per square inch' can never be collected in a meaningful way. All figures describing biting power in such terms can be traced to either unfounded rumor or, in some cases, to newspaper articles with no foundation in factual data." -Dr. I. Lerh Brisbin. Again with the myth that they are able to chew as they grip with their frount teeth is impossible, "This is anatomically impossible! Humans can move their mandibles forward to a degree because of an essentially flat dental plane. Dogs have greatly projecting and interlocking canine teeth and projecting cheek teeth that prevent movement forwards and backwards. I have a dog skull on my desk as I write and this type of movement can not be made." - Dr. I. Lerh Brisbin.

Place The Power In The Right Hands

Pit Bulls need to stop being looked at as monsters, and killing machines. Pit Bulls are dogs, simply put. They are powerful dogs, but that power is not evil unless placed into the wrong hands. Pit Bulls are a wonderful versatile breed that can be used for many purposes. Contrary to popular believe fighting is not the only thing they excel at. They are a breed determined to please it's owner, thus if we start using them for the right purposes these dogs make wonderful therapy, guide, rescue, service,weight pulling, agility and companion dogs. All they need is the right kind of guidance, and owner.


Chandra from California on January 08, 2018:

It ludicrous some of the things people come up with about pitbulls.

nz tk on July 27, 2014:

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I uave 2 female pitts nd a simple shush stops them gpin over the play limit. Author needs to get more unfo esp with skull diagrams of dachshunds, chihuahuas nd poodles. Rili??? Look at rotties and mastiffs.. stil got sm negativity.. just gotta train em well.. they know my voice and even a cough from me stops em getting to agro wif each other

Luke Russell from Melbourne, Victoria, Australia on June 25, 2013:

You Pitbull Apologists can call it whatever you like, but I think LOCK is an appropriate term, not only has this been demonstrated, the testimonials from the many victims and their rescuers have dismissed your lies and propaganda for what they are. In the Solesky case, which is the Maryland case in which pit bulls were declared to be vicious as a matter of law, one of the exhibits was a demonstration of the locking jaw. Animal control officers played with a rope and a pit bull until the latter clamped down on the end of it. Then the officers shot the dog with a tranquillizer dart. The dog became semi-conscious and limp. The officers then threw the other end of the rope over something in the ceiling, and pulled the rope until the pit bull, with the other end clamped in its jaws, was dangling in mid-air. They left the dog there for some period of time, barely conscious, limp, but clamped onto the rope. Do the pit bull's jaws lock? Is the word "lock" a metaphor for what the dog's jaws do? Perhaps the word is the closest we can use in English to describe this behavior of the dog. But in the end, what matters is that this dog has a characteristic that others do not. That is certainly true. And the fact that pit bull owners are counselled to carry a break stick when they walk the streets with their dogs is another indication that these dogs have a characteristic that other dogs do not. If that isn't considered 'LOCKING' Jaw then I have no idea what would would be needed to prove such a thing. And if it is just determination, pitbulls have a strange way of remaining determined while unconscious.

Chris on February 22, 2013:

They are a very intelligent breed with a high tendency to please, very loving and very devoted. Owning a pitbull can be no different than owning a SUPERBIKE instead of a car, u have to be careful n learn how to handle ur machine, if not, calamity may lie right around the corner. The same can b said about this breed, they're very loving but if the owner is ignorant this animal's needs it's the equivalent of releasing a madman on the streets of a major city with a nuclear bomb. My advice, every breed is different, research which is best for u according to ur lifestyle. If u love pits b prepared to give a lot of love n affection without holding back n u'll get the best companion ever!

tim on January 20, 2013:

Its not a locking jaw that allows the dogs to hold on to a toy or rope for long periods of time. its determination. they are a terrier. terriers are determined dogs at what ever they do that's why when they originally were creating these dogs they chose a terrier to mix with a muscular dog. THey don't like to give up. in the right hands they are an amazing dog.

pamela terry on January 16, 2013:

Pit bulls can be deadly. I learned this when my daughters pit bull attacked and killed my tiny little chipoodle. This pit bull would not stop attacking my dog. Once she started nothing could have stopped her. I screamed so loud and long that I could not talk for 3 days. I am now traumatized. I can't eat or sleep and the murderous rampage that dog went on has me terrified. I see it over and over in my mind. This dog would not stop not even long after my little dog was dead. I loved my little dog and I loved the pit bull but now? I hate her with all that I am. I will hate pit bulls for the rest of my life because of this unprovoked act of violence. So don't tell me pit bulls are not dangerous. This dog has never had anything but love and a secure home. And still she killed. So think twice before bringing one into your home especially if you have other animals or children. Those dogs are deadly.

Dee on November 08, 2012:

I write a APBT. magazine with the AADR reg. I would love to use this in the winters mag. can I use this? If so email me at

Ranikai on September 26, 2012:

So you're saying ANY breed of dog could continue holding on while a two by four is smashed repeatedly against its head?! I don't think so. I think "lock jaw" means the dogs don't let go. Whatever the reason behind it is, their skull or their teeth or a combination. They're bred for fighting, they're built to take hits. They're also built to give them, only makes sense if they're fighting dogs.

Any dog can be dangerous, of course. No one disputes this, what a silly thing to say. However, any dog is NOT built to kill - Pitbulls are, and they do. They're at the center of the majority of dog attacks. You can't discount that fact. Yes, "Pitbull" is a general term. So I'm saying in general, those types of dogs are the dangerous ones. It's like owning a machete vs a knife. Wouldn't the knife be just as useful, but safer? It'd also do less damage if it fell into the wrong hands. Why risk lives on a breed of dog? Get some priorities.

If your priorities are only about a breed of dog humans have made vs human well-being, then how about getting some regulations in place for only responsible people owning them and needing a screen process, if it's true it's only the owners and not the dogs, maybe its perception will change if the owners do something to show they're serious about changing its image. Also, having to take out an insurance policy when you own one; can't pay the price, don't get the dog. Entitlement of something built like a weapon, no matter how lovable most are, is a dangerous thing.

j on August 17, 2012:

I love pit bulls breeds! I'll never adopt anything but pits, the majority of pits I have known (including my own) have been the most affectionate, intelligent, and social dogs. They really get a bad rep for the wrong reasons!

scully on June 15, 2012:

While I do agree that pit bulls are "just dogs", they are physically bred for aggression and fighting. This fact is indisputable. They have huge, strong muscles around their jaws for grabbing onto and holding something, and the average person might not know what to do with a pit's dog-based aggression, and easy arousability. Pits also "lie" about their intentions to other dogs. An average dog will "bow" to another dog in order to communicate that he wants to play. A pit might return this bowing gesture, then launch into a brutal attack. Definitely a surprise to the other dog who thought he was just going to play. While I believe that pits can be trained well by caring and competent owners, I think that for the average person, a pit is just too much to handle.

Joey Rivas on June 09, 2012:

I have an american pitbull terrier and he is the best pet I have ever had. I had to break up a fight between him and another pit. During all this comotion my did bit my right hand. He immediately released when he saw it was me. When all was over, he came to me and started caring for my wounds. He is not a viscous dog but an extremely loyal and protective part of the family. He saw the other dog as a threat because it was getting to close to my daughters, 7 and 15.

Mike O on May 13, 2012:

Well believe me the puppies you have Isabel will play rough. It's all part of their growing up routine. The only time you should correct is when one of them yelps or it escalates. It's all part of establishing dominance and is natural. You need to be that leader in that relationship. I have a 1 1/2 year old American pitbull terrier and she is just a dream. I understand how it can be concerning but trust me they love and NEED that exercise. Socialization and exercise are the two ABSOLUTELY definitive needs for pitbull ownership. My little girl, Sookie, gets slightly destructive if she doesn't get exercise but nothing too grievous. I'm glad I stumbled across this and glad so many people support pitbulls. My wife and I have both caught flack for having a pitbull, a pitbull mix, and a Rottweiler. One lady even blatantly suggested I put my baby girl to sleep BECAUSE she is a pitbull. I, luckily, was not there to correct this woman's point of view. My little girl has made pitbull haters into lovers and in fact I'm in the middle of organizing a pitbull awareness walk in my town because pitbulls have such a horrible rap and it is unfair to hate a breed because of what they are. I personally encourage everyone considering a dog to look at your lifestyle and choose what is best for you. If you are an active person that has time to train a dog and doesn't mind a challenge, because they are some of the most stubborn dogs alive, then maybe a pitbull is for you. Lord knows they need someone to step in and love them.

ISABEL on May 08, 2012:


jason on April 21, 2012:

Mostly pitbull has the eye of shark that is hardly to really predicting on their actions ,, from my experience those breed are to be raise from puppy by good training from good family or owner , that can know what pitbull is all about .. good loyality .. it bother me when I see pitbull at wrong hands. And mostly judge on the breed by a neglect owner that lead the bad result ... Judge on the breed by a good raisng life

jimmy17a on April 17, 2012:

luvmypits, if you let you children playu around with your pitbulls like that you are a complete idiot. these are not toys they are animals and due to the power they possess they can be dangerous. please reflect on this

curtis severn on April 02, 2012:

they are the best dogs in the world love them

luvmypits on March 21, 2012:

Quite honestly I am very happy that there are people out there spreading the word that Pit bulls are not all bad!!! In all fact, any other dog can be just as vicious as a pit bull, the difference in the attention is due to the fact that they are strong dogs! I have a grandmother who has a that is a vicious dog! Whenever sitting in its chair or on her lap and you come over to it, you're getting bit, it's happened to my children. I personally own two pitbulls, one being full pit and the other we believe to be mixed with lab, but not positive. Point being they are the BIGGEST goof balls ever. They are fun to play with, loving, and eager to please. We regularly test their aggression just to keep an eye on it...with out even a blink I can stick my foot or hand or any other object on them, next to them, or even in their food while eating. We roll them on their backs, paws up to check for any resistance or anger, and they just want their tummies rubbed! And in regards to children....I have 2 children(3 and 6)! My youngest tortures them as kids do, including pulling tails, pushing them out of the way, and even squeezing cheeks! But they also all snuggle no problem. Don't be quick to judge, I was very nervous when my husband presented the suggestion of getting a pit but I was the one to get the 2nd one!

Ruth on February 29, 2012:

Yes, they are beautiful and very intelligent but they are more dangerous than most common breeds. Their mouth hava a devilish strenght and their jaws are very powerful. They are dangerous, don´t tell me they are not because I know, I have see it, been in touch with them. Once they grab the arm of a person, even the owner, they won´t let go easily.

alexandra on October 15, 2011:

pitbulls are the olny dogs i will have i love them with my heart

Mrs. J. B. from Southern California on February 01, 2011:

What useful and educational material. As the owner of 4 pits I thank you for helping to spread the word about how great these dogs really are...

Brian Andrews on January 25, 2011:

I have two dogs with powerful jaws. One of them is my red nose pitbull, and my other dog is my rottweiler witch has the strongest psi among the domesticated dogs along with powerful jaws. Yes folks believe it or not rottweilers have the same thing aswell

Travis Roberts on January 24, 2011:

I have a 8yo American bulldog that I got from a guy who couldn't keep her anymore when I got her home I layed down on her and pulled all over her and was biteing her everywhere to "test" her now my grandkids play with her and she has never made anykind of threat to them or anyone else best dog ever

Chris on January 08, 2011:

I am the owner of a 2.5 yr old pink and white American Pitbull Terrier, I also have a yr English Mastiff, and a 6 yr old bulldog lab mix. All are females and all live in and out of my house. My pitbull is the best of the three. My mastiff and my bulldog mix have both bit me out of anger, my pitbull has never even once growled at me and is very loyal to me. Just a baby/child has to be raised in the right hands so does a pitbull or both could become monsters.

will m on December 21, 2010:

I am the owner of an 11 month old blue brindle American Pitbull Terrier and she's the love of my life. You truly can't ask for a more loyal companion and loving animal. I highly recommend this breed for any active person and they are misunderstood...I've never even heard mine growl!

val on December 10, 2010:

the pit bull do is a good and playful dog if u are not an intruter some pits will attack humans but allwas for a reson if u tran them well they will be the best frend to you.

Dave Ruble on September 11, 2010:

The idea of "locking" jaw is not a physical trait. Perhaps the authors should possess just a little bit of canine knowledge before ponitificating. Read Raymond Coppinger. All predators have a kill sequence and domestication removes parts of the sequence leaving the animal "stuck" on one part of the progression. Locking jaw is a physiological trait. And believe me, it does happen.

Thomas on May 17, 2010:

I have been taught that certain dog breeds - the pit bull being one, has two sets of biting muscle allowing them to maintain a bite by relaxing the muscles independently. I've also been taught that these dogs can use these muscles as a "jack" in order to achieve a stronger bite. Is this incorrect?

Resolver2009 from Bournemouth, UK / Oslo, Norway on February 17, 2010:

Fantastic article Eternal Evolution. You go deep, and the information is very extensive. Fascinating. Btw, just published the seventh episode of my thriller series Three Minutes to Midnight, would love it if you checked it out. Thanks! See you around Eternal. Alex

makayla thurston on January 13, 2010:

i love that some one care so much for these dogs! i know i do i have a pit all this info is so true! all pits want to do is love you and play tug-of-war! they don't want to fight!!!!!!!!!!! thanks for caring for the pits!!!!!!!!!!!!!

kartika damon from Fairfield, Iowa on December 02, 2009:

Thanks so much for this and the other articles on Pit Bulls - am doing some research on them now!

mia irawati on August 28, 2009:


ronibgood on April 27, 2009:

Very interesting points.

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