Plaque behind your teeth is soft bacterial film, and in most cases you can remove it yourself with the right brushing angle and cleaning tools. The tricky part is that the back surfaces of your teeth, especially the lower front ones, are the hardest spots to reach with a toothbrush and the fastest to accumulate buildup. If that plaque has already hardened into tartar, a yellowish or dark crusty deposit you can feel with your tongue, no amount of brushing will take it off. That requires a professional cleaning.
Why Plaque Builds Up Behind Your Teeth
The back sides of your lower front teeth are the single most common spot for heavy plaque and tartar buildup, and it’s not because you’re doing something wrong. The submandibular salivary glands empty through a duct that opens right at the floor of your mouth, directly behind those lower front teeth. The saliva from these glands is alkaline, which encourages calcium salts to form. That mineral-rich saliva constantly bathes the area, giving plaque everything it needs to harden into tartar quickly.
On top of that, the tongue side of your teeth is simply harder to see and harder to reach. Most people angle their toothbrush well on the front-facing surfaces but rush through or skip the backs entirely. The result is a sticky film that thickens day by day. If plaque sits undisturbed, it traps calcium and other minerals from your saliva and calcifies into tartar. Once that happens, it’s cemented to the tooth and can only be removed with professional instruments.
How to Brush the Back of Your Teeth Properly
The technique that matters most here is getting your bristles aimed at the gum line on those hard-to-reach back surfaces. The American Dental Association recommends holding your toothbrush at a 45-degree angle to the gums and making short, gentle back-and-forth strokes for each tooth. After those short strokes, sweep the brush away from the gum line toward the biting edge of the tooth. This motion pulls plaque out of the gum pocket rather than pushing it in.
For the back of your front teeth, both upper and lower, tilt the brush vertically so you can fit the toe (the tip) of the brush head behind each tooth. A lot of people try to jam the brush in horizontally, which doesn’t work because there isn’t enough room. Holding it upright and using the front few rows of bristles gives you much better contact with the surface. Spend a few seconds on each tooth rather than sweeping across the whole arch at once.
An electric toothbrush with a small, round head can make this easier. The compact head fits behind the lower front teeth more naturally, and the oscillating or sonic motion does some of the work for you. Whether you use a manual or electric brush, the key is the same: angle toward the gum line, use gentle pressure, and give each tooth individual attention.
Clean Between Teeth, Not Just the Surfaces
Brushing alone misses the tight spaces between teeth where plaque thrives. For these areas, you have three main options: string floss, interdental brushes, and water flossers. All three work, but they’re not equally effective for everyone.
Interdental brushes, those tiny bottle-brush-shaped picks, remove more plaque between teeth than traditional string floss. Research comparing the two found that interdental brushes also reduced gum pocket depth more effectively, and patients found them easier to use. If you have any gaps between your teeth or mild gum recession, these brushes slide in easily and scrub the surfaces floss can only slide past.
Water flossers use a pulsating jet of water at controlled pressure to flush plaque from between and behind teeth. They’re particularly good at reaching the back sides of molars, where string floss struggles to make full contact. One study found water flossers reduced plaque between teeth by about 82%, compared to roughly 63% for string floss. The pressurized stream also disrupts bacterial colonies below the gum line in ways that a flat piece of floss can’t. If dexterity is a problem, or if you find yourself skipping flossing because it’s tedious, a water flosser is a strong alternative.
For the best results, combine your toothbrush with at least one interdental tool. Brushing handles the broad surfaces; floss, interdental brushes, or a water flosser handle the gaps.
Mouthwash as a Backup, Not a Fix
Mouthwash won’t scrub plaque off your teeth, but certain formulas slow down new plaque formation after you’ve brushed. The active ingredients to look for are essential oils (like thymol, eucalyptol, and menthol), cetylpyridinium chloride, or chlorhexidine. These compounds kill bacteria by disrupting their cell membranes, making it harder for new colonies to establish on clean tooth surfaces.
Essential oil-based rinses are the most widely available over the counter and appear in nearly half of all mouthwash products. They work by penetrating bacterial membranes, increasing their permeability until the cells break down. Sodium bicarbonate, found in some rinses, takes a different approach: it physically disrupts the sticky matrix that holds plaque together without killing bacteria directly. Neither type replaces mechanical cleaning, but rinsing after brushing and flossing adds a layer of protection, especially behind the lower front teeth where plaque reforms fast.
Don’t Use Metal Scrapers at Home
If you can feel a hard ridge of tartar behind your teeth, it’s tempting to buy a dental scraper online and chip it off yourself. This is a genuinely bad idea. Metal scaling instruments are sharp, and without training, you risk scratching your enamel, which increases tooth sensitivity and creates rough spots where new plaque sticks even faster. You can also slice into your gum tissue, causing recession that exposes sensitive tooth roots. Perhaps worst of all, you can accidentally push tartar fragments under the gum line, where they cause abscesses and deeper infection. Professional hygienists train for years to use these tools safely. Leave the scraping to them.
What Happens at a Professional Cleaning
If your plaque has already mineralized into tartar, a dental hygienist will remove it using either hand instruments or an ultrasonic scaler. The ultrasonic tool vibrates at high frequencies, breaking the bond between calcified deposits and the tooth surface while a water spray flushes the debris away. For heavier buildup, especially below the gum line, your dentist may recommend scaling and root planing. This is a deeper cleaning that reaches into the gum pockets to remove tartar from the root surfaces and smooth them so gums can reattach more tightly.
For most people at average risk, professional cleanings every six months keep tartar in check. But if you build up tartar quickly, have a history of gum disease, smoke, have diabetes, or deal with chronic dry mouth, cleanings every three to four months are often more appropriate. The ADA emphasizes that the right schedule depends on your individual risk factors, not a universal rule. If you’ve noticed that tartar reappears behind your lower front teeth within weeks of a cleaning, mention it. Your dentist can adjust both the frequency and focus of your visits.
A Daily Routine That Targets the Problem
Plaque starts reforming on your teeth within hours of brushing, so consistency matters more than perfection. A practical daily routine for keeping the backs of your teeth clean looks like this:
- Brush twice a day for two minutes, deliberately spending time on the tongue-facing surfaces. Tilt the brush vertically behind your front teeth and angle at 45 degrees elsewhere.
- Use an interdental tool once a day. Interdental brushes or a water flosser give the best results behind the lower front teeth and between molars.
- Rinse with an antimicrobial mouthwash after your evening routine to slow overnight plaque formation.
The reason plaque keeps coming back behind your teeth isn’t that your teeth are flawed. It’s that the anatomy of your mouth funnels mineral-rich saliva right to that spot, and conventional brushing habits skip over it. Once you adjust your angle, add an interdental tool, and stay consistent, the buildup slows dramatically. Any tartar that’s already formed needs professional removal, but everything you do at home determines how fast it comes back.