The best way to brush teeth, according to clinical trials

The Modified Bass technique is taught everywhere

If you asked a dental hygienist how to brush teeth properly, you would almost certainly hear about the Modified Bass technique. Dental schools teach it, hygienists demonstrate it, and patient education pamphlets illustrate it. The method requires holding your brush at a 45-degree angle to the gum line, using short back-and-forth vibrating strokes, then sweeping the bristles toward the chewing surface.

The logic behind this specific approach seems sound. The angled bristles reach into the sulcus (the shallow groove where tooth meets gum), and the vibrating motion disrupts plaque along and just below the gum line, where gingivitis starts. The technique has been standard practice for decades.

The question the trials address is whether this specific hand position and stroke pattern actually removes more plaque than any other way of moving a brush across teeth. If the Modified Bass technique truly outperforms alternatives, the evidence should show it. If stroke direction and hand angle don’t matter much, the trials will show that too.

The best way to brush teeth isn’t about stroke direction

A 2023 randomized trial directly compared the Modified Bass technique against the rolling technique and a control group using participants’ usual brushing method.¹ Ninety adults brushed for four weeks using their assigned technique. Researchers measured plaque scores and gingival bleeding at baseline and follow-up.

The result: no statistically significant difference in plaque removal or gingival health among the three groups. The Modified Bass technique, despite its biomechanical rationale and widespread teaching, did not outperform the rolling technique or people’s habitual brushing patterns.

A 2014 split-mouth trial tested whether stroke direction matters at all.⁹ Each participant brushed one side of the mouth vertically and the other side horizontally for two weeks. Plaque indices were identical between the two sides. The direction you move your brush does not affect how much plaque comes off.

A separate split-mouth study asked whether the sequence in which you brush different areas of your mouth matters.⁸ It does not. Starting with upper molars versus lower incisors made no difference in final plaque scores.

A 2020 systematic review synthesized the evidence across all manual brushing techniques.² The review found insufficient evidence to recommend any one technique over another for plaque control or gingival health. The Modified Bass, rolling, circular, and horizontal scrub techniques all produced similar outcomes when used by trained participants.

The table below compares plaque reduction across techniques from the 2023 randomized trial:¹

Plaque and gingival outcomes by brushing technique after 4 weeks (n=90)

The differences fall within measurement error. You can brush vertically, horizontally, in circles, or with the Modified Bass angle, and the plaque outcome will be the same if you cover all surfaces with consistent pressure and duration.

Electric toothbrushes barely outperform manual brushes

Marketing materials suggest powered toothbrushes deliver dramatically better results than manual brushing. The meta-analyses tell a more modest story.

A 2025 systematic review and meta-analysis compared powered and manual toothbrushes in children.³ Powered brushes reduced plaque scores by a mean of 11% more than manual brushes. Gingival inflammation decreased by 6% more with powered brushes. Both differences were statistically significant but clinically small.

A 2022 network meta-analysis examined different types of powered brushes.⁴ Oscillating-rotating brushes showed the most consistent benefit over manual brushes, but the effect size remained modest. Side-to-side powered brushes and sonic brushes showed no advantage over manual brushing in most comparisons.

A 2016 meta-analysis looking at long-term disease prevention found powered brushes reduced gingivitis marginally more than manual brushes after three months of use.⁵ The difference narrowed over time, suggesting that user behavior (frequency, duration, thoroughness) matters more than the brush type.

Recent trials in specific populations show similarly small effects. A 2026 trial in patients with clear aligners found powered brushes removed 8% more plaque than manual brushes in a single brushing session.¹² A 2021 trial in patients with fixed orthodontic appliances found powered brushes reduced plaque by 14% more than manual brushes after three months.¹⁷

Powered toothbrushes do work slightly better on average, but the advantage is smaller than the variation in how thoroughly and consistently people brush. A manual brush used properly twice daily for two minutes will outperform an electric brush used hastily once a day.

The trials testing novel brush head designs (triple-headed,¹⁰ dual-headed,¹¹ multi-branched bristles¹⁴) found no meaningful improvement over conventional brush heads. The shape of the bristle tuft matters less than whether the bristles contact all tooth surfaces with enough pressure to disrupt biofilm.

Pressure and duration matter more than technique

If technique and brush type account for small differences, what separates effective brushing from ineffective brushing?

A 2017 double-blind randomized trial tested whether bristle end-rounding affects gingival abrasion.¹⁸ Participants brushed with brushes that had poorly rounded, moderately rounded, or well-rounded bristle tips. Poorly rounded bristles caused measurably more gingival abrasion, especially when combined with hard brushing pressure. The trial directly showed that excessive pressure damages gum tissue.

A 2025 feasibility trial used smart toothbrushes with pressure sensors to track brushing behavior in schoolchildren.¹⁹ The data showed wide variation in brushing pressure and coverage. Children who applied consistent light-to-moderate pressure across all tooth surfaces had better plaque control than those who brushed hard in some areas and missed others entirely. The pressure sensor feedback helped children maintain more consistent technique.

Duration is the other load-bearing variable. The two-minute recommendation comes from trials showing that plaque removal plateaus around 120 seconds of brushing. Brushing for 30 seconds removes some plaque. Brushing for 60 seconds removes more. Brushing for 120 seconds removes nearly all accessible plaque. Brushing longer than two minutes adds little benefit.

Frequency also matters. A 2024 systematic review and meta-analysis found that twice-daily toothbrushing reduced the risk of hospital-acquired pneumonia in ventilated patients.⁷ The mechanism is straightforward: brushing removes oral bacteria that can be aspirated into the lungs. Brushing once daily cuts that bacterial load. Brushing twice daily cuts it further.

Cochrane reviews of oral hygiene instruction programs show that teaching people how to brush (the specific technique) produces small, short-term improvements that fade over weeks.⁶²⁰ Teaching people to brush twice daily for two full minutes, and to replace their brush every three months, produces larger and more durable improvements.

Bristle design has a marginal effect. A 2025 randomized trial compared three manual toothbrush bristle patterns.¹³ All three designs removed plaque equally well when used for two minutes. Bristle flexibility, tuft arrangement, and head size made no difference in clinical outcomes as long as the bristles reached all tooth surfaces.

The best way to brush your teeth, according to the evidence

The trials show that how you brush matters far less than how long, how often, and how thoroughly you brush. Stroke direction, hand angle, and brushing sequence are not meaningless, but their effect on plaque removal is small and inconsistent across studies. Pressure, duration, and coverage are the variables that separate effective brushing from theater.

The evidence supports these specific practices:

Brush twice daily. Morning and before bed. Frequency matters more than technique.

Brush for two full minutes. Use a timer or a brush with a built-in timer. Plaque removal plateaus at 120 seconds. Most people brush for 45 seconds and believe they brushed for two minutes.

Use light to moderate pressure. If your bristles splay out after a month, you are brushing too hard. Hard pressure damages gums without removing more plaque. Soft pressure that keeps the bristles in contact with all tooth surfaces is sufficient.

Cover all surfaces. The lingual surfaces of lower molars and the buccal surfaces of upper molars are the most commonly missed areas. Divide your mouth into quadrants and spend 30 seconds per quadrant.

Replace your brush every three months. Worn bristles remove plaque less effectively. Frayed bristles abrade gum tissue more.

An electric toothbrush is optional. If you brush manually for two minutes twice daily with proper pressure and thoroughness, the clinical outcome will be nearly identical to using an electric brush. If you struggle with duration or thoroughness, an oscillating-rotating electric brush will compensate slightly.

The Modified Bass technique is optional. If you were taught the Bass technique and it works for you, continue. If you brush with a rolling motion, circular scrub, or horizontal strokes, the evidence does not support switching. The technique you can sustain consistently for two minutes is the correct technique.

The evidence does not support the widespread teaching that one technique is superior to all others. The best way to brush teeth is the method you will actually perform thoroughly, twice daily, for two full minutes. That might be the Modified Bass technique. It might be a horizontal scrub. The trials show both work when done consistently with appropriate pressure and duration.