Plaque builds up behind your teeth faster than almost anywhere else in your mouth, especially along the lower front teeth where saliva ducts concentrate minerals. The good news: if it’s still soft plaque, you can remove it yourself with the right brushing angle, the right tools, and a little daily consistency. If it has already hardened into tartar, a chalky yellowish or brownish deposit you can feel with your tongue, only a dental professional can safely take it off.
Why Plaque Collects Behind Your Teeth
The back surfaces of your teeth (dentists call them lingual surfaces) are harder to see and harder to reach. Most people angle their toothbrush toward the front of their teeth out of habit, barely grazing the inside. Meanwhile, saliva glands sit right under your tongue, bathing the backs of your lower front teeth in mineral-rich fluid. That’s useful for protecting enamel, but it also means any plaque sitting there calcifies into tartar faster than plaque elsewhere in your mouth.
Plaque itself is a sticky, colorless film of bacteria that forms within hours of brushing. Left alone for about 24 to 72 hours, it begins hardening. Once it fully mineralizes into tartar (also called calculus), it bonds to your enamel so firmly that no amount of brushing or flossing will break it loose.
The Brushing Technique That Actually Works
For the inside surfaces of your front teeth, turn your toothbrush vertical so the bristles point up (for upper teeth) or down (for lower teeth). Then make several short up-and-down strokes, letting the toe of the brush head do the work. This is the single most effective change most people can make, because a horizontally held brush simply can’t reach these surfaces well.
For the inside surfaces of your back teeth (molars and premolars), angle the brush at roughly 45 degrees toward the gumline, just as you would on the outer surfaces, and use short back-and-forth or circular strokes. The key is pressing gently enough that the bristles splay slightly into the gum margin without bending flat. Aggressive scrubbing doesn’t remove more plaque; it just damages your gums.
Spend at least two full minutes brushing overall, and make a conscious effort to give the lingual surfaces equal time. Most people rush through these areas in a few seconds. Setting a timer or using a powered toothbrush with a built-in timer helps.
Electric vs. Manual Toothbrushes
A Cochrane review found that electric toothbrushes achieve about 21% greater plaque reduction and 11% greater reduction in gum inflammation compared with manual brushes over three or more months of use. The advantage comes largely from the consistent motion and smaller brush heads, which make it easier to clean awkward spots like the backs of your lower front teeth. If you struggle with plaque buildup in those areas specifically, switching to an electric brush is one of the simplest upgrades you can make.
That said, a manual toothbrush used with good technique still does the job. The vertical stroke method described above matters more than the type of brush you use.
Interdental Tools for Hard-to-Reach Spots
Plaque also hides in the tight spaces between teeth, including the back sides where teeth overlap slightly. Flossing reaches these contact points, but interdental brushes (the tiny bottle-brush-shaped picks) tend to perform even better when the spaces between your teeth are large enough to fit them.
A 2015 meta-review in the Journal of Clinical Periodontology found moderate evidence that interdental brushes used alongside regular toothbrushing reduce both plaque and gum inflammation, ranking them among the most effective interdental cleaning methods. A separate 2018 analysis in the Journal of Periodontology ranked interdental brushes as the most likely “best” option for reducing gum inflammation, while floss ranked near the bottom. The advantage is especially clear for people with any degree of gum disease or naturally open spaces between teeth, where the brush bristles can physically contact more tooth surface than a thin strand of floss.
If your teeth are tightly spaced, floss or a water flosser may be more practical. The best tool is the one you’ll use every day.
Toothpaste That Slows Tartar Formation
Tartar-control toothpastes contain ingredients that slow the crystallization of plaque into hardened deposits. The most common active agents are zinc salts (particularly zinc citrate), pyrophosphates, and a compound called sodium hexametaphosphate. These work by interfering with mineral crystal formation on the tooth surface.
Clinical trials have shown that zinc salts can significantly reduce and even prevent tartar formation compared with regular toothpaste. Sodium hexametaphosphate has demonstrated tartar reductions as high as 55% versus a standard formula. These toothpastes won’t dissolve tartar that already exists, but if you’re prone to rapid buildup behind your lower teeth, using one daily can meaningfully slow the process between dental cleanings.
Why You Shouldn’t Scrape Tartar Off Yourself
Once plaque has fully hardened into tartar, it forms a bond with your enamel that brushing and flossing cannot break. You may be tempted by dental scrapers or ultrasonic devices sold for home use, but using these without training carries real risks. Metal tools in untrained hands can gouge enamel, leading to permanent sensitivity and increased vulnerability to decay. Sharp picks can cut gum tissue, cause bleeding and recession, and expose sensitive root surfaces.
Home tools are also rarely sterile, so any cut you create can introduce bacteria into your bloodstream. Perhaps the most dangerous risk is accidentally pushing tartar deeper under the gumline, which can trigger abscesses and bone loss. Even home ultrasonic devices, despite being marketed as safe, can cause friction burns on gums and soft tissue injuries when they slip.
Removing the visible tartar you can see also creates a false sense of security. The deposits below the gumline, the ones that cause the most damage, are invisible and unreachable without professional instruments and training.
Signs That Buildup Has Gone Too Far
If plaque and tartar have been accumulating behind your teeth for a while, your gums will tell you. Early warning signs include redness, swelling, tenderness, and bleeding when you brush or floss. You might notice persistent bad breath that doesn’t go away after brushing, or a rough, bumpy texture on the back of your lower front teeth that you can feel with your tongue.
More advanced signs point to gum disease progressing: gums pulling away from the teeth (making them look longer), teeth that feel loose or sensitive, and pain while chewing. In a healthy mouth, the small pocket of space between each tooth and the surrounding gum measures 1 to 3 millimeters. As tartar pushes below the gumline and triggers inflammation, those pockets deepen, creating even more space for bacteria to thrive.
What Happens at a Professional Cleaning
A dental hygienist uses hand instruments called scalers and curettes, along with ultrasonic tools, to break tartar’s bond with your enamel without damaging the tooth surface. They’re trained to work both above and just below the gumline, reaching the subgingival deposits you can’t see or access at home. The process is called scaling, and for most people it takes 30 to 60 minutes.
If you’re someone who builds tartar quickly behind your lower front teeth, your dentist may recommend cleanings more frequently than the standard twice a year. Some heavy tartar formers benefit from cleanings every three to four months. This isn’t a sign that your hygiene is poor. Tartar formation rates vary significantly between people based on saliva chemistry, and some people simply mineralize plaque faster regardless of how well they brush.
A Daily Routine That Keeps Plaque in Check
Plaque starts reforming within hours of brushing, so consistency matters more than perfection. Brush twice a day for two minutes, using the vertical stroke technique on the inside of your front teeth. Clean between your teeth once daily with interdental brushes or floss. Use a tartar-control toothpaste if you’re prone to buildup. And consider an electric toothbrush if you find it difficult to reach those lingual surfaces with a manual one.
Pay attention to texture. Run your tongue along the backs of your lower front teeth after brushing. They should feel glassy smooth. If you feel a rough or gritty patch, you’ve missed a spot. Go back with your brush angled toward that area and give it another pass. Catching soft plaque before it hardens is the entire game, because once it becomes tartar, your toothbrush can’t help you anymore.