Informes & Estudios

How often should we actually be cleaning our teeth?

PD Dr. Kristina Bertl, PhD MSc MBA

We are used to telling our patients, ‘Clean your teeth twice daily!’. But where does this idea come from, and is it really necessary to brush twice daily? What would happen if we only brushed our teeth once every two days?

How often should we actually be cleaning our teeth?

A research group from North America and Brazil investigated this question and looked at different intervals of self-performed oral hygiene among 42 periodontitis patients undergoing maintenance therapy (Maier et al. 2020 & Reiniger et al. 2021). In detail, the participants were divided into three groups:

  1. Self-performed oral hygiene twice daily
  2. Self-performed oral hygiene once daily
  3. Self-performed oral hygiene once every two days

The patients’ pocket probing depths and plaque and bleeding indices were observed over a period of three months. The analysis of the results showed very clearly that periodontitis patients in maintenance therapy who only brush their teeth once every two days will experience a deterioration in their condition. The plaque and attendant bacteria that built up over 48 hours was sufficient to pose a risk to periodontal health, and these patients exhibited a substantial increase in bleeding indices and signs of inflammation by the end of the study.

Based on the results of these two publications, we can summarize that once-daily effective brushing might possibly suffice, but that brushing only once every two days leads to a significant decline in periodontal health, and among periodontitis patients undergoing maintenance therapy, increased bleeding indices and signs of inflammation occur within three months. In terms of daily dental practice, given the fact our patients have a tendency to forget to brush their teeth from time to time, we should stick to the recommendation of twice-daily oral hygiene.


Maier J, Reiniger APP, Sfreddo CS, Wikesjö UME, Kantorski KZ, Moreira CHC. Effect of self-performed mechanical plaque control frequency on gingival health in subjects with a history of periodontitis: A Randomized Clinical Trial. J Clin Periodontol. 2020;47:834– 841.
Reiniger APP, Maier J, Wikesjö UME, Moreira CHC, Kantorski KZ. Correlation between dental plaque accumulation and gingival health in periodontal maintenance patients using short or extended personal oral hygiene intervals. J Clin Periodontol. 2021; 48: 834–842.