What made Suarez's attack so shocking was not just his play-acting afterwards - he fell to the ground clutching his mouth as if he were the victim - and his denial of any offence (he claims Chiellini "bumped into me with his shoulder"), but that this is the third time the Uruguayan has used his mouth as a weapon in a high-profile match.
It might be thought that he had learnt his lesson from previous lengthy match bans, or at least some techniques for self-control from the anger management course he attended after the last attack, on the Chelsea player Branislav Ivanovic.
All of which might make him an interesting subject for study to a criminologist.
Prof David Wilson, at Birmingham City University, jokes (though only slightly) that Suarez's behaviour is certainly worthy of his attention: "He first bit in November 2010, when he was playing for Ajax, and then he bit again when he was playing for Liverpool against Chelsea last year. The gap between his first and second incidents was 28 months, and the gap between the second and third incidents is 15 months. If I had my criminological hat on, I would expect the gap between this week's biting and the next incident to be even shorter."
That might not be possible if Fifa imposes the maximum 24-month or 24-match ban.
Suarez may not be found to have committed an offence. But it is clear that the sight of an adult biting another in public is much more disturbing than throwing a punch, even if both might be criminal assault.
Nottingham Trent University psychologist Dr Mark Griffiths says: "How many times in football have we seen fisticuffs, elbowing, even headbutting? All these things are awful, but they have become almost part and parcel of the game. But biting is so rare, that is one of the reasons why it is so shocking."
Also, psychologists explain, biting shocks us because it involves using an intimate and soft body part that one normally associates with pleasure.
And here we touch on a basic tenet of Freudianism. According to the founding father of psychoanalysis, all sexual pleasure and anxieties are rooted in different periods of childhood, the first of which is the oral stage, when babies explore the world through their mouths. Toddlers often then go on to bite to attract attention and will continue doing so until a parent teaches them otherwise.
Behaviour learnt in the oral stage of development is the explanation, Freudians believe, for everything from a predilection for chewing pencils all the way to full-blown vampirism. It is no coincidence that Freud wrote his seminal work on psychosexual theories within a decade of the publication of Bram Stoker's Dracula. The vampire, spreading fear in a sexually repressed society, is a powerful metaphor. And the genre has never been out of fashion for long, with vampires finding a new lease of life (in a watered-down form) in the Twilight saga.
Nowhere is the line between pleasure and pain so blurred as with biting. As with all sexual practices, there is a technical term: obtaining pleasure from biting or being bitten is called odaxelagnia. This is an act that happens between two consenting adults, often teenagers experimenting with "love bites".
It becomes more problematic when one half of the couple has no say in the matter.
Dr Michael Bloomfield, clinical research fellow at Imperial College London, says: "Biting is about putting a part of someone else's body into your mouth, and is cannibalistic. That is not to say that everyone who bites is a cannibal, but on a deeper, psychological level it is about cannibalism, and that is why we find it so shocking. If we were to rank it among all the crimes, cannibalism is about as big a no-no as possible."
Suarez may have a chronic problem with biting, but he is not the first sportsman to use the tactic, either to intimidate an opponent or simply because they have lost their temper. The most famous example is Mike Tyson biting Evander Holyfield's ear midway through a boxing match in 1997, causing blood to spurt and the commentator to say, in an unintentionally comic way, "that's nasty stuff there; it looks to be almost a fight".
There have been high-profile cases in rugby, too. South Africa prop Johan le Roux was sent home from a tour of New Zealand in 1994 after being found guilty of biting the ear of an opponent.
More recently, England rugby player Dylan Hartley was suspended for eight weeks for biting Ireland player Stephen Ferris during a Six Nations match.
In rugby, biting seems slightly less horrific because of the nature of the scrum, with people's heads frequently shoved up against opponents' bodies, suggesting less premeditation is required for a bite.
But in football there is no reason why your mouth should be close to an opponent.
"To bite someone, you have to get very close, you have to put your head - the place you want to protect the most in a conflict - right up against them," says Professor Wilson.
"It literally marks your partner as belonging to you. In evolutionary terms, there are many animals who bite their mates as a way of controlling them before engaging with them sexually."
It is hard to escape the sexual nature of biting. It is sometimes even used as a method of attack during sexual crimes, Professor Wilson says.
"It is nearly always a form of sadism. Often I'd be looking at children who had been bitten by a paedophile or women who had been bitten on their sexual organs. I really don't want to over-egg it, but Suarez has a mild psychological issue."
That may be true. He certainly has some problems, possibly the biggest of which is that he is in denial that he has done anything wrong, again behaving like an overgrown toddler. Dr Saima Latif, a psychologist, says: "Trying to shift the blame is also a classic form of childish behaviour. Most children confronted with something they have done, will immediately recourse to lying."
The reason for this, say experts, is because his footballing parent-figures - whether club or country - have always refused to castigate his bad behaviour, giving him licence to transgress time after time.
Fifa has the power to send Suarez to the naughty step, but he probably needs to spend some time under treatment before he can return to the playground. As Dr Latif says: "To get to the root of the problem and address it effectively, he requires psychological therapy."
