ZentFlex pressure-sensitive toothbrush

Diary of a reformed aggressive brusher: A review of the ZentFlex toothbrush

March 25, 2020
I’ve been brushing my teeth for 40 years and in the dental profession 22 years. You'd think I'd have my brushing technique down pat. But here's what I learned using the ZentFlex pressure-sensitive toothbrush.

We spend countless hours per year teaching our patients to properly brush their teeth. Today's electric toothbrushes even try to help us with this: they have built-in timers and pressure sensors, and some use artificial intelligence to encourage a complete toothbrushing experience. It's all part of a united effort to keep our patients on track. But electric toothbrushes have a smaller market share among Americans today. According to Statista, in 2019 nearly 266 million Americans used a manual toothbrush1 and approximately 123 million used an electric toothbrush.2 If so many people are still using manual toothbrushes, how can we ensure that they are utilizing proper toothbrushing technique? And is there a product that can help reinforce good technique?

Enter the ZentFlex pressure-sensitive manual toothbrush (figure 1). This unique, and elegantly designed, and reasonably priced new product aims to solve some of the trickiest toothbrushing problems that have hampered manual toothbrushes. But before I describe my experience with a ZentFlex, here's a little more about those manual toothbrushing challenges.

Manual toothbrushes: Today's challenges

A person with adequate dexterity and brushing technique can remove plaque as effectively with a manual toothbrush3 as an electric toothbrush, but brushing with a manual toothbrush seems to yield inferior results.4 Why is this? For one thing, people brush their teeth for only 47 seconds on averagewhich is far below the recommended two minutes.5

If we as clinicians can't get through to patients about how long they should brush their teeth, then how can we expect them to learn how to do things such as use proper brushing pressure—a key part of successful manual toothbrushing?

Proper brushing pressure has been a known challenge for some time. Aggressive toothbrushing can lead to gingival abrasion, recession, and loss of tooth structure.6 In fact, pressure that is greater than 150 g can be damaging to gingival tissues7 and has been linked to greater dentinal hypersensitivity.8 But does anyone know how much pressure 150 g equates to clinically? (I certainly didn't.)

I have always considered myself a "professional toothbrusher." After all, I have an associate degree in dental hygiene, a bachelor's degree in dental hygiene, and a dental degree, plus I am a board-certified prosthodontist. Surely I should be able to safely brush my teeth for the correct amount of time and with the proper amount of pressure...

Boy, was I wrong. 

Just how wrong was I? I didn't know until I came across the ZentFlex toothbrush, which addresses the pressure issue head-on. ZentFlex is a manual toothbrush that bends and makes a "clicking" sound when greater than 150 g of pressure is applied (figures 2 and 3).

Here’s my experience with ZentFlex, as recorded in my "toothbrush diary." 

Day one: Four clicks

Dear diary: I am extremely surprised to discover how little pressure caused this brush to bend. I applied an appropriate pressure on most of my tooth surfaces, but quickly realized that I tend to "scrub" localized areas in my mouth. It required multiple attempts to correct my technique.

Day two: Two clicks

Dear diary: I was trying to be mindful of the pressure I was applying to my teeth while brushing, but it’s tough to break old habits. I seem to have figured out the proper approach to apply a safe amount of pressure to the questionable areas from the day before, but I still have some work to do.

Day three: Zero clicks

Dear diary: Success! I have been able to figure out how to brush my teeth with a manual toothbrush without applying unnecessary—or potentially damaging—pressure to my tooth surfaces. I have found that brushing with less than 150 g of pressure to my tooth surfaces has instinctually increased my brushing time. I am finally practicing what I preach with manual toothbrushing: more time, less pressure.

Day four and after

Dear diary: I have found that brushing with ZentFlex has encouraged mindful toothbrushing with proper techniques. I shared this toothbrush with some of my colleagues and my patients and the consensus seems to be the same: “I cannot believe how much pressure I was applying to my teeth!” To be completely honest, my brush still clicks from time to time, reminding me that my aggressive brushing habit has not completely resolved.

Lessons learned

I have spent numerous years discussing the facts about RDA (relative dentin abrasion) values and toothpaste abrasivity. Despite conflicting evidence,9 many commercially available toothpastes have been criticized for playing a role in tooth abrasion, gingival recession, and even noncarious cervical lesions.10 

My next statement is pure conjecture: If, in general, we are applying too much pressure to our tooth structure and marginal gingiva with our manual toothbrushes, I’m wondering if we might owe some of our toothpaste-manufacturing colleagues an apology. I would argue that it's a question worth pondering.

I encourage all of you to give the ZentFlex pressure-sensitive toothbrush a try. For me, it was an incredibly eye-opening experience to comprehend that when using a manual toothbrush, I have been brushing my teeth with too much pressure. This simple, clever technology can encourage safer brushing habits for manual toothbrushers. I would be interested to hear how many clicks you get!

Editor's note: This article first appeared in The Product Navigator, a twice-monthly newsletter from DentistryIQ, Dental Economics, and RDH. To subscribe, visit the DentistryIQ subscription page.


  • Statista Research Department. U.S. population: Do you use manual toothbrushes? Statista. https://www.statista.com/statistics/278116/us-households-usage-of-manual-toothbrushes/. Published August 20, 2019.
  • Statista Research Department. U.S. population: Do you use power toothbrushes? Statista. https://www.statista.com/statistics/278156/us-households-usage-of-power-toothbrushes/. Published August 20, 2019.
  • Goh EXJ, Lim LP. Fact for Fiction? Powered Toothbrushing is more Effective than Manual Toothbrushing. Oral Health Prev Dent. 2017;15(1):23-32.
  • Yaacob M, Worthington HV, Deacon SA, Deery C, Walmsley AD, Robinson PG, Glenny A. Powered Versus Manual Toothbrushing for Oral Health. Cochrane Database Syst Rev. 2014;17(6):CD002281.
  • Procter & Gamble. Personal interview.
  • Heasman PA, Holliday R, Bryant A, Preshaw PM. Evidence for the Occurrence of Gingival Recession and Non-Carious Cervical Lesions as a Consequence of Traumatic Toothbrushing. J Clin Periodontol, 2015;42(S16):S237-255.Ganss C, Schlueter N, Klimek J. Tooth Brushing Habits in Uninstructed Adults—Frequency, Technique, Duration and Force. Clin Oral Investig. 2009;13(2):203-208.Sehmi H, Olley RC. The Effect of Toothbrush Abrasion Force on Dentine Hypersensitivity In-Vitro. J Dent. 2015;43(12):1442-1447.Bartlett DW, Shah P. A critical review of non-carious cervical (wear) lesions and the role of abfraction, erosion, and abrasion. J Dent Res. 2006;85(4):306-312.Hunter ML, Addy M, Pickles MJ, Joiner A. The role of toothpastes and toothbrushes in the aetiology of tooth wear. Int Dent J. 2002;52:399-405.
    Pamela Maragliano-Muniz, DMD, is the chief editor of DentistryIQ. Based in Salem, Massachusetts, Dr. Maragliano-Muniz began her clinical career as a dental hygienist. She went on to attend Tufts University School of Dental Medicine, where she earned her doctorate in dental medicine. She then attended the University of California, Los Angeles, School of Dental Medicine, where she became board-certified in prosthodontics. Dr. Maragliano-Muniz owns a private practice, Salem Dental Arts, and lectures on a variety of clinical topics.

    Also by Dr. Maragliano-Muniz

    Coronavirus impact on dental practices: All things HR [Video]

    Coronavirus impact on dental practices: Taxes, new laws, and cash flow [Video]

    Editor's Note: Highlights from the Chicago Dental Society's Midwinter Meeting