Most human mouths have roughly 32 teeth of an assortment of different shapes, but not in this case. These teeth are unnaturally large, straight, and uniformly rectangular — bearing a striking resemblance to white bricks or the ivory keys of a piano, and sometimes not even distinguishing where the maxilla's teeth end and the mandible's teeth begin.
Depending on how it's used this trope can be either Played for Horror or Played for Laughs — and sometimes both at the same time — but is always meant to look weird and offputting. When used for comedic purposes, this trope is chiefly a form of Sudden Anatomy cueing the audience in that the character — specifically one that doesn't usually have block-shaped teeth — is up to something; and usually sets up some form of dental retribution. In cases where it's played for horror, this trope is used to indicate at the very least that something is... off... about the person these teeth belong to. This trope is popular with the Monster Clown archetype and is often paired with a Slasher Smile, some yellowing, and a bit of crookedness — all the better to better show them off while highlighting how uncanny the person who possesses them is.
A Subtrope of Scary Teeth that often overlaps with More Teeth than the Osmond Family. This style of teeth is often used as a sister trope to Tooth Strip due to its simplicity, but characters just having block-shaped teeth as part of the artistic style — without connotations of Uncanny Valley — doesn't count as this trope.
Not to be confused with a slapstick comedy gag trope common to Western cartoons where a character ends up with actual piano keys arranged like teeth in their mouth — usually as a result of having the piano dropped on them.
- Attack on Titan: Several Titans have mouths sporting an abnormal number of identical rectangular teeth of varying sizes, further amping up their Uncanny Valley features. However, some Titans stand out in this regard:
- The aptly named Smiling Titan has a mouth drawn back in a disturbing rictus-like grin, exposing every single one of her several dozen identical rectangular teeth.
- The Attack Titan — when held by Eren Yeager — has no lips or cheeks, just a massive number of identical teeth set directly into its jaws; which prevents it from talking but comes in very handy for biting. As the series progresses, the Attack Titan becomes an antagonistic force, seemingly influencing Eren to turn on his friends and try to claim the other Titan powers for himself.
- The Colossus Titan — who literally kicks off the series' plot — has dozens of identical rectangular teeth, though, while enormous, they're comparatively small to the rest of its body — amping up the Uncanny Valley already dialed Up to Eleven by its lack of skin.
- Assassination Classroom: Koro-sensei sports a brick-toothed grin that only adds to his cute-but-creepy Smiley Face-with-tentacles appearance, and is the cherry on top of him being a borderline Eldritch Abomination with enough power to destroy the planet. When he gets angry, however, his teeth turn into fangs. Even when he was human, he'd sport a brick-toothed grin for comical effect when he was being perverted.
- Mayuri Kurotsuchi, Soul Society's resident Mad Scientist, is completely unfettered and more than happy to conduct horrific experiments on not only himself but also anyone unlucky enough to catch his attention and/or exist within 50 feet of him. Likely as a result of his self-experimentation, his teeth are uniformly rectangular in shape and are far too long — and are usually exposed in a gruesome Slasher Smile. At one point, he even paints them yellow.
- Shinji Hirako and Nnoitra Gilga are both drawn with long, rectangular teeth, and zero distinction where their upper jaw's dentition ends and their lower jaw's begins. The former is the enigmatic leader of the Visored — a group of Hollowfied Soul Reapers — and while creepy is on the side of good. The latter is a sadistic and misogynistic Arrancar and member of the Espada and is one of the villains fought during the Hueco Mundo Invasion arc.
- Boruto: Unlike the first form of Kaguya Ōtsutsuki's Ten-Tailed Beast, which had hundreds of fangs, Jigen's Ten-Tailed Beast has a large mouth lined with two rows of uniformly-shaped humanoid teeth — setting it apart from its predecessor and making it all the more unnerving.
- Gunnm: Desty Nova, a Mad Scientist who is completely unfettered when it comes to the depravity of his research, often sports this kind of teeth in a Slasher Smile when he talks about his favourite topics: Karmatron Dynamics and flan.
- JoJo's Bizarre Adventure: Kraft Work, Sale's Stand, has teeth like the ivory keys of a piano, contrasting with just about every other Stand in the series.
- One Piece: The pirate Scratchmen Apoo is a comical figure whose Devil Fruit ability lets him turn his body parts into musical instruments. As a result, his teeth literally look like piano keys, and he can even produce musical notes by pressing them.
- The Rising of the Shield Hero: The Slave Merchant is a short, rotund man who styles himself after a circus ringmaster and constantly sports a too-wide grin of unusually rectangular teeth. His theatrically cheerful attitude belies a deeply sinister nature and serves mainly as a lure for potential customers and victims alike: he initially intended to enslave Naofumi; and eagerly offered to pay a significant amount to buy Raphtalia back upon seeing how much she'd grown, with the implied intent of selling her into prostitution due to him upping his offer when informed she was still a virgin.
- The Joker is often drawn with too many too-long teeth as part of his trademark rictus grin, highlighting his nature as a psychotic and sadistic killer.
- Norman Osborn is frequently drawn sporting a ghoulish grin as the Green Goblin, as are the other members of the Goblin clan. His rival, the Hobgoblin, stands out in particular, especially when drawn by Todd Mc Farlane.
- In his humanoid form of The Clown, the demonic Violator is often drawn with these as an indicator that he's a) not human, and b) evil — whenever he's not just drawn with straight-up fangs.
- Billy Kincaid, a pedophilic child murderer, is often depicted sporting a depraved grin with way too many uniform teeth — particularly in the animated series.
- The titular symbiote-augmented supervillain-turned-antihero was originally drawn with these before quickly transitioning into fangs, and some artists go back to this look for the sheer creepiness factor.
- In Rick Remender and Cullen Bunn's run, Agent Venom briefly amalgamated the Venom symbiote with a derelict car to create the Venom Mobile, turning its hood into a mouth lined with far too many block-shaped teeth.
- Cletus Kasady is sometimes drawn sporting a Slasher Smile with these — not counting his Jagged Mouth and/or fanged More Teeth than the Osmond Family as Carnage — to highlight his maniacal and nihilistic bloodlust.
- The Brave Little Toaster: The firefighter Monster Clown seen in Toaster's nightmare has a vertically too-wide Slasher Smile that bares not just his disturbingly long teeth, but a grotesque amount of gum tissue. Further amping up the nightmare fuel, he speaks without opening his mouth, just moving his lips around his teeth.
- Laurel and Hardy: The butler from The Laurel-Hardy Murder Case — played by Frank Austin — smiles ghoulishly at the main characters after bidding them goodnight, with his teeth seeming to extrude as he grins at them. And when he closes his mouth his smile becomes all the more disturbing.
- The Lord of the Rings: The Mouth of Sauron is a man who — as his moniker suggests — serves as the mouthpiece for the Dark Lord Sauron, confronting and being killed by Aragorn before the final battle in The Return of the King. As part of his grotesque appearance, his lips have been cut off to reveal yellowed teeth that are far too long and look on the verge of rotting out of his head.
- In a Dark, Dark Room and Other Scary Stories: In "The Teeth", a boy is walking home at night and meets three strangers one-by-one who grin at him, showing increasingly longer teeth. At the sight of the third man, with his too-long, yellow teeth, the protagonist just runs.
- Dragon: Marked for Death: The Ogres fought as Giant Mooks have lip-less mouths lined with blockish teeth, accentuating their hideous appearances. The first boss of the game — the Ogre Prince, and his father the Ogre King — are particularly cruel and sadistic, with their introductory cutscene being the former chowing down on a helpless villager while the latter laughs.
- Fate/Grand Order: Rider of the Resistance — aka Christopher Columbus — is a depraved and sadistic Neutral Evil conquistador who has a number of sprites that show him sporting a "daring smile" — that is to say, distorting his whole face into a nightmarishly grotesque vertically-wide grin that exposes blockish teeth; a trait his Super-Deformed artwork exaggerates for comical effect.
- The Legend of Zelda: The ReDeads in The Legend of Zelda: Ocarina of Time, The Legend of Zelda: Majora's Mask, and The Legend of Zelda: The Wind Waker are zombies with large rectangular teeth — in the former made all the creepier by the coffin-wood masks they wear.
- Wario has large block-shaped teeth that accentuate his comically grotesque appearance, and even puts them to use in the Super Smash Bros. series.
- Danganronpa: Trigger Happy Havoc: The villainous mascot Monokuma sports these on his black half, alongside a jagged red eye.
- Charby the Vampirate: Zeno has tall, uneven rectangular teeth.
- Happy Tree Friends: While most of the cast sport these in addition to cutesy buck teeth, owing to the simplistic art style; Flippy the Bear stands out as an example given that he's a timid war veteran... until something happens to set off his PTSD and his Ax-Crazy split personality Fliqpy — who has fangs instead — takes over to brutally slaughter everyone he comes across.
- Weebl & Bob: The animated song Scampi stars a rather paranoid man with red hair, an oddly-shaped cleft chin... and enormous yellow teeth that take up most of his face and don't move as he sings.
- Courage the Cowardly Dog: The aptly named "Freaky Fred" was a Perpetual Smiler, always showing off his long, flat, white teeth, emphasizing his creepy nature.
- Looney Tunes
- This style of teeth is commonly used for artistic simplicity and comedic effect, and is often shown being used as doors, being shattered like panes of glass, and for other Cartoon Physics-laded slapstick gags. However, characters who don't normally have teeth like this — such as Sylvester the Cat, Wile E. Coyote, Daffy Duck (who shouldn't even have teeth in the first place and usually doesn't), and Taz (who is usually depicted with massive fangs) — are often depicted spontaneously sporting this style of teeth while being conniving or attempting to conceal a wrongdoing they committed or are about to commit. This sharp departure from their usual appearance is frequently used as a cue that they're up to something and sets up the aforementioned dental horror gags as comeuppance.
- In the banned World War II propaganda cartoon Tokio Jokio, Japanese people are depicted with massive rectangular teeth as part of a racist caricature.