A Funny Animal or Civilized Animal without the benefit of Feather Fingers or Humanlike Hand Anatomy can usually substitute their mouth. Including for tasks that require opposable thumbs, because screw you, evolution.
Humans who have been bound or otherwise incapacitated are also not averse to this, in a pinch. Rule of Funny is powerful like that. However, this trope can also be played for drama, if a character is forced to use their mouth as a "hand" to escape from a desperate situation.
Truth in Television in that many animals do utilize their jaws this way (such as a cat carrying her kittens,) although they can't usually write letters or fence very well.
Compare Now That's Using Your Teeth! and Cutlass Between the Teeth, which can intersect with this if the character also fights this way rather than just carrying the weapon. Can overlap with Multi Purpose Tongue.
- Dairy Queen Lips: The lips use their mouth to pull a veil off a DQ value menu and write with chalk.
- Kill la Kill: Nui Harime, the Grand Couturier (of the bad guys), is shown to sew with her mouth mighty fine, when sewing with her hands is no longer an option.
- In a very early arc, the villain Zabuza lost the use of both arms after Naruto (with the help of Kakashi) beats him. Then, before everything's settled, Zabuza's employer Gato shows up with multiple armed men, saying that You Have Outlived Your Usefulness to Zabuza and that his men are gonna execute him. An angered Zabuza asks Kakashi for a kunai, which he catches with his mouth; he then proceeds to charge at the armed men and cut them down with the kunai between the teeth, using his tongue to flip the kunai's direction. In the manga, he also beheads Gato this way.
- Naruto Uzumaki also uses his mouth as a "third hand" to hold kunai and rolls as seen in◊ these artworks, mostly seen in the first series as well in Shippuden.
- One Piece: Roronoa Zoro, the closest thing to the first mate of the protagonist pirate crew, fights by elaborately using up to three full-size swords, first two in hands, third goes in his mouth. In one scene, he uses this technique to clean with three mops at once while infiltrating an enemy organization... which quickly blows his cover, forcing him to use them as Improvised Weapons.
- In The Seven Deadly Sins during the Vaizel Fight Festival, Hawk the pig proves to be rather proficient in making a doll-sized dress with just his mouth from a single piece of cloth for a shrunken Elizabeth.
- In Peanuts, Snoopy often carries his supper dish in his mouth, usually while kicking Charlie Brown's back door.
- Jonathan Joestar's living disembodied head in the JoJo's Bizarre Adventure Alternate Universe fic Sapphire Heartverse plays this trope for laughs, as, like in canon, Dio steals Jonathan's body as his own but Jonathan's head survives and lives a mostly normal existence in Dio's mansion interacting with the other characters. As he has no hands, he compensates by using his mouth, be it to write, draw, open doors, carry objects or even help in cooking breakfast.
- Moana: During the battle with the Kakamora, Moana, who's carrying her rooster Hei-Hei with her, needs both her hands to make use of an Improvised Zip Line; she frees her hands by grabbing Hei-Hei (at the neck) in her mouth to carry him with her.
- In Oliver & Company, Tito the chihuahua is the hot-wire expert of Fagin's gang. He's seen pulling wires from underneath a limousine's dashboard with his teeth and jumping the connections by holding select wires in his mouth and letting his saliva act as the conductor. He would later activate a freight elevator in Sykes' lair by pulling a wire with his teeth, then pressing the exposed end against the circuit board.
- Maximus the horse in Tangled can hold a swordfight against Flynn Rider with a sword in his mouth.
- Batman: One of the gadgets Batman has is a small lockpick he keeps in his mouth. This is for when he finds himself shackled to walls and such, and his mouth is at least good enough to let him free himself if he can get close enough to the locks.
- All Tomorrows: The Titans use a modified lower lip like an elephant trunk to grasp objects, and the Sail People use their tongues in a similar way.
- Known Space: Puppeteers use their two mouths as hands. The mouths are perfectly suited for this, even possessing little fingerlike projections.
- All mammals in the Spellsinger Verse are intelligent and capable of speech, but most of the hoofed species lack the ability to handle objects with their forelimbs. A variety of mouth-operated tools allow them to manipulate objects.
- Various characters in Warrior Cats, being, well, cats, manipulate objects using their mouths, mostly moss (to carry water) or sticks (to carry things they don't want directly in their mouths).
- In Dark Souls, Sif is a giant wolf boss that carries a sword in his jaws. He is able to swing the sword and shift it around his mouth quite adeptly.
- In Dwarf Fortress, a mod giving cats a grasping mouth allows to avoid error message "Cat cancels Store Item in Stockpile: Too injured". (They sometimes think that their hands are cut.)
- Final Fantasy VII: A more realistic version occurs when Tifa is strapped to a chair and sees that a guard dropped the key. She retrieves the key with her feet then, for lack of other options, uses her mouth to unlock the first hand restraint.
- Kingdom Hearts II: While in the Pride Lands, Sora wields the keyblade in his mouth due to taking on a lion form.
- Metal Gear Solid 4: Guns of the Patriots: In the game's climax, Raiden, after having lost his arms earlier in the game, holds off a team of enemy cyborgs with nothing but a sword in his mouth so that Snake can continue progressing the final level and defeat the Big Bad once and for all.
- In Spore in tribal stage the chief of a tribe without hands holds his staff in his mouth. Around 3:45 in this film.
- Quadruped fighters from the Super Smash Bros. series, such as Ivysaur and Duck Hunt carry lightweight items in their mouth to maintain mobility.
- Them's Fightin' Herds: Arizona swings a lasso using her mouth, and if an opponent is caught she reels them in by pulling on it with her teeth.
- In one Pixie and Brutus strip, Brutus draws Evil Eyebrows on a teddy bear for a self-defense lesson, holding the crayon in his mouth.
- Sailor Ranko: In a scene when Ranko thinks she's a cat, she carries Ami to safety by her collar, like a cat would carry a kitten.
- The northhounds and southhounds of Hamster's Paradise are wolf-like hamster descendants with no opposable digits, and thus use their mouth to hold and grasp objects. This has been a major hindrance to the advancement of their society, though based on an earlier script, they domesticate ape-like hamsters to circumvent this.
- Aqua Teen Hunger Force: In "Rubberman", Lance The Duck Made From Used Condoms yearns for arms, so he and Meatwad chop off Carl's. During the credits, Carl is shown still alive without his arms trying to work his phone. He dials a number with his tongue.
- Dilbert: In one episode, after Dilbert accidentally knocks all satellites out of alignment, the world devolves back into Renaissance times. One holdover from the digital ways is shown panicking, trying to get his phone to work, and is put in a pillory for his troubles. Once he is, he's seen dialing the phone with his tongue.
- In My Little Pony: Friendship Is Magic, ponies that aren't using their magic or hooves to carry or manipulate things sometimes utilize their jaws — the series is inconsistent with this.
- Since he has no arms or legs, this is about the only way that Bob Oblong from The Oblongs can do anything, including changing his bedridden mother's adult diaper.
- Xiaolin Showdown: After Master Fung is put in a full-body cast in "Finding Omi", he uses Kimiko's laptop to communicate and a stick in his mouth to operate the keyboard.
- The artist Sarah Biffen was born without arms and only vestigial legs but managed to learn how to sew, write, paint, and use scissors with her mouth.
- Golden Retrievers were bred to retrieve game undamaged, resulting in very "careful" mouths. They can be trained to safely carry around eggs and other very delicate objects.
- Hamsters, chipmunks, pocket gophers, and several other types of rodents use their cheek pouches to carry much larger amounts of food with their mouths than an animal without hands could otherwise transport.
- Pelicans have large lower beaks that they use to scoop water and take lots of fish in one swoop, then drain the water like a colander before swallowing the catch.
- Power wheelchairs for quadriplegic Real Life humans are sometimes equipped with mouth controls.
- Elephants have this by virtue of their famously dexterous and manipulative trunks being in part derived from their upper lip.
- Insects such as ants often carry and manipulate objects in their mouths, since they usually need all six legs for walking, and the legs are only useful for carrying in some specialized cases like mantids.
- In contrast to the other members of the Primates order, lemurs use their mouths more frequently than their hands to manipulate objects.
- Paul Alexander, one of the last survivors of polio, lives in an iron lung. That means he cannot use his hands and has greatly restricted mobility. He typed a memoir using his mouth, a hammer-shaped plastic piece, and a keyboard.