Settle first, look second
A teeth check goes badly when it starts as a wrestling match. Choose a calm moment — during lap time, not after being chased around the enclosure — and sit her on a towel on your lap, body supported, facing away from you so she feels held rather than confronted. Let her settle and take a treat from you first. Then, with one hand steadying her gently, use a thumb to lift the upper lip just enough to see the front teeth. The whole look takes seconds. If she struggles hard, stop and try again another day; a forced mouth inspection teaches her to dread handling, and the stress can injure a wriggling animal far more surely than a postponed check harms her.
The front four: what healthy looks like
A guinea pig has four prominent front teeth, two upper and two lower, and they grow continuously throughout her life, worn down by chewing. In a healthy mouth the upper and lower edges meet squarely, the pair looks even in length from left to right, the surfaces are smooth and pale, and the teeth sit in a neat line without gaps or overlap. Look at the gums while the lip is up: they should be pink and calm, not swollen, bleeding, or receding from one tooth.
The changes worth spotting early
The classic early warning is a slanted wear line, where the meeting edges run diagonally instead of level — a sign the teeth are no longer grinding evenly against each other. Also look for one tooth noticeably longer than its partner, a tooth that has snapped or chipped, discolouration, teeth beginning to cross or splay outward, and lower teeth that seem to be angling inward toward the tongue. Run a finger along the outside of her jaw and under the chin: a wet chin, matted fur below the mouth, or dribbling as she eats points to a mouth that hurts, whatever the front view showed, and an asymmetrical lump along the jawbone deserves a vet's opinion.
The part of the mouth home checks cannot reach
Be clear about the boundary of this check: the molars at the back, which do the heavy grinding, sit behind full cheeks and cannot be viewed at home. Guinea pigs develop spurs and overgrowth on those hidden teeth that no lip-lift will reveal, and trying to lever the mouth open with household objects risks broken teeth and a terrified animal. So the home check works as one half of a system. The other half is behaviour: eating more slowly, dropping half-chewed food, choosing soft vegetables and leaving hay, producing smaller droppings, or losing interest in gnawing. Any of those signs means the back of the mouth needs a vet's instruments, even on a day when the front four look perfect.
How often, and what supports healthy wear
A brief front-teeth look once a week, folded into normal handling, is often enough to catch a slant or a break while it is still a small problem. Between checks, the conditions for even wear are dietary: constant access to hay drives the long, sideways chewing strokes that grind the whole tooth row, while a bowl-fed diet of soft food lets growth outrun wear. Suitable gnawing material and prompt vet attention after any tooth break — a broken tooth changes how its opposite number wears within weeks — keep a minor event from becoming a misaligned mouth. Never be tempted to trim teeth at home; incorrectly clipped teeth can shatter below the gum or split lengthways, turning a manageable issue into an emergency.
Record the look, not just the worry
Because dental change is gradual, memory blurs: was that slant there last month, or is it new? A one-line dated note after each check — front teeth level, eating hay well — turns guesswork into evidence a vet can use. In KinsLe, your guinea pig's Pet Passport keeps those dental notes with her other health records in one packet, so if a pattern does develop, the timeline travels with her to the appointment instead of being pieced together from recollection.