Exploring Toothbrushing Duration Among Adults: A Systematic Review

ABSTRACT

Aim

There is a need for greater understanding of the average brushing time among individuals. Since the average brushing time remains unclear, this study involves a systematic review to assess this aspect of oral hygiene practices and how it has evolved over the years.

Material and Methods

The PubMed‐MEDLINE and Cochrane‐CENTRAL databases were searched from their inception until January 22, 2025, to identify relevant studies. Eligible clinical trials included healthy adults who performed self‐brushing. The primary outcome was the average duration of a toothbrushing exercise in seconds/min, with an ‘a priori’ distinction made between PTB and MTB users. A secondary outcome assessed the correlation between publication year and brushing duration. Sub‐analyses differentiated between powered toothbrush (PTB) and manual toothbrush (MTB) users.

Results

Twelve eligible papers were retrieved, providing 16 evaluations with considerable variability in clinical and methodological design. Fourteen evaluations involved MTB users, and two involved PTB users. The study found that uninstructed adults (≥ 18 years) brush their teeth with an MTB for an average of 87 s. Notably, with moderate strength in the observation, there is a trend that brushing duration among MTB users appears to increase over publication years. PTB users averaged 143 s of brushing time.

Conclusion

Within the limitations of the present study design, there is moderate certainty that the average MTB toothbrushing duration among uninstructed adults is approximately one and a half minutes, with a trend suggesting an increase in brushing duration over the years. This duration falls short of the recommended guidelines, whereas PTB users brush for over 2 min on average.

Trial Registration

PROSPERO registration number: CRD42024565180

1. Introduction

Oral diseases rank among the most prevalent diseases worldwide. The Global Burden of Disease 2015 study reports that approximately 3.5 billion people suffer from oral disease conditions, with dental caries and periodontal diseases being the most common [1]. Risk factors for caries encompass physical, biological, environmental, behavioural, and lifestyle‐related elements, and include issues such as high levels of cariogenic bacteria, inadequate saliva production, insufficient fluoride exposure, suboptimal oral hygiene practices, inappropriate infant feeding practices, and socioeconomic disadvantages [2]. The signs of carious demineralization are seen on the hard dental tissues, but the disease process is initiated within the bacterial biofilm (dental plaque) that covers a tooth surface [2]. Gingivitis is a reversible inflammatory periodontal disease resulting from interactions between the biofilm and the host's immune‐inflammatory response [3] and is the key risk factor for the onset of periodontitis [4]. Severe periodontal disease and dental caries are the primary causes of tooth loss among adults [3]. Edentulism, or complete tooth loss, is a significant global public health issue affecting over 10% of adults aged 50 and older [5]. This condition has profound implications for oral and overall health, contributing to problems such as reduced chewing function, social isolation, and diminished oral health‐related quality of life [6]. The primary strategy for preventing dental caries and periodontal diseases involves effectively removing plaque through proper oral hygiene [7].

Currently, the primary method for maintaining good oral hygiene is mechanical plaque removal through toothbrushing [8, 9, 10, 11, 12]. This toothbrushing is most effectively accomplished using a manual toothbrush (MTB) or powered toothbrush (PTB) [8, 13, 14, 15]. Despite the advancements in modern technology, MBTs remain popular worldwide due to their affordability and widespread availability [16]. MTBs, after a single brushing exercise, achieve an average reduction of 42% in the plaque score index [16], while PTBs achieve a 46% reduction [17]. Sub‐analyses from both reviews indicate that increased brushing time correlates with further improvements in plaque score reductions. Recently it is recommended that teeth should be brushed for a sufficient duration to ensure effective cleaning of all tooth surfaces [18]. Globally, irrespective of the toothbrush used, it is recommended that individuals should brush their teeth with a fluoride toothpaste at least twice a day for 2 min for optimal oral health [18, 19, 20, 21]. This 2 min brushing advice is incorporated as feedback in PTBs with a timer [22]. While the general hypothesis is that all tooth surfaces can be effectively cleaned within 2 min, this overlooks factors such as the number of teeth, the presence of oral diseases, and manual dexterity [18].

In contrast, research from over two decades ago calculated that the average brushing time in the general population was closer to 45 s [23]. This figure falls significantly short of the most advocated duration of 2 min [19, 20, 21]. Extending brushing time to the widely accepted minimum of 2 min can yield clinically significant oral health benefits [24] and therefore dental care professionals (DCPs) should encourage patients to brush for longer durations. However, there is limited insight into the average brushing time among individuals. This study aims to conduct a systematic review to assess and provide insights into average brushing times for MTB and PTB users separately, thereby contributing to a better understanding of oral hygiene practices. Additionally, these insights can inform recommendations, guide policy implementation to increase brushing duration, and support the adjustment of current guidelines.

2. Materials and Methods

This systematic review was prepared and described in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and the provided guidance via MOOSE [25], a reporting guideline from Meta‐Analysis of Observational Studies in Epidemiology. Additionally, to support Synthesis Without Meta‐analysis (SWiM) [26], the SWiM‐reporting items were evaluated. The protocol detailing the review method was developed ‘a priori’ after initial discussion among the members of the research team. The review is registered under number CRD42024565180 with the International Prospective Register of Systematic Reviews (PROSPERO) [27]. The study was also approved by the Institutional Review Board of the Academic Center for Dentistry Amsterdam, the Netherlands, under number 2023–64985.

2.1. Focussed Condition‐Context‐Population (CoCoPop) Question [28]

What is the average duration of a toothbrushing exercise using either an MTB or PTB among uninstructed adult participants?

As a secondary outcome, the trend in brushing duration measured in seconds over the years of publication was examined.

2.2. Search Strategy

A structured and comprehensive search strategy was developed to identify all relevant publications on the duration of a toothbrushing exercise among adult participants. The electronic databases The National Library of Medicine, Washington, D.C. (MEDLINE‐PubMed) and Cochrane‐CENTRAL were used for this purpose. The last electronic search was conducted on October 15, 2024, and updated on January 22, 2025. The search strategy and employed search terms and keywords are presented in Table 1 and modified according to the acquisitions for each database used.

TABLE 1.

Search terms used for PubMed‐MEDLINE and Cochrane‐CENTRAL. The search strategy was customized according to each database that was searched. The following terms were used in the search strategy.

((toothbrushing [MeSH Terms]) OR (toothbrushing OR toothbrush* OR toothbrush)) AND (time OR duration OR seconds OR minute OR minutes)

Note: The asterisk (*) was used as a truncation symbol.

2.3. Screening and Selection

Study titles and abstracts obtained from the search were screened independently by two reviewers (YSRH & TMJAT) using the Rayyan [29] web application. The reviewers were blinded to each other's results during the screening process. Disagreements in the screening and selection process were resolved by consensus or, if disagreement persisted, by arbitration through a third reviewer (DES). The papers that fulfilled all the inclusion criteria were processed for data extraction. All references cited in the selected papers were checked to identify additional potentially relevant studies.

Studies were deemed eligible for inclusion if they conformed to the following criteria:

• Publications written in the English language.

• Full publications (no conference abstracts)

• Controlled Clinical Trials (CCT) or Observational studies

• Studies conducted with human participants

  • ○
    ≥18 years old
  • ○
    In good general health (without systemic disorder or pregnancy)
  • ○
    Without a diagnosis of periodontitis
  • ○
    Without orthodontic fixed appliance
  • ○
    Without removable prosthesis
  • ○
    Without dental implants
  • ○
    Non‐dental employees and students

• Interventions: manual toothbrush OR powered toothbrush

• Self‐performed brushing by the participant.

• Single‐brushing exercise

• Outcome parameter of interest: brushing time/duration

Self‐reported questionnaires were excluded for the analysis.

2.4. Heterogeneity Assessment

Clinical and methodological heterogeneity was assessed across the studies. Methodological heterogeneity was judged by evaluating variations in study design, while clinical heterogeneity was evaluated based on participant and group characteristics, differences in toothbrush design (MTB and PTB), and variations in regimen and instructions in toothbrush use.

2.5. Methodological Quality Assessment

Two reviewers (YSRH & TMJAT) scored the methodological qualities of the included studies using the ROBINS‐I tool as described by Sterne et al. [30]. The ROBINS‐I tool (“Risk Of Bias In Non‐randomized Studies—of Interventions”) evaluates the risk of bias in estimates of the effectiveness or safety (benefit or harm) of an intervention in studies that did not use randomization to allocate interventions. The ROBINS‐I tool views each study as an attempt to mimic a hypothetical pragmatic randomized trial, covering seven distinct domains through which bias might be introduced. The use of “signalling questions” helps ROBINS‐I users assess the risk of bias within each domain. The judgements made for each domain are then consolidated to determine an overall risk of bias for the outcome being assessed [30]. Disagreements in the quality assessments were resolved through discussion until a consensus was reached. If disagreements persisted, resolution was achieved by involving a third reviewer (DES).

2.6. Statistical Analysis

2.6.1. Data Extraction

The data from the publications that met the selection criteria were extracted and processed for further analysis. Two independent reviewers (YSRH & TMJAT) used custom‐designed data extraction forms to record mean brushing durations and their standard deviations (SDs). If studies provided a standard error (SE) of the mean, these values were converted to SD based on the sample size (SD = SE × √N). For this review, data from adult participants in multiple age groups was extracted from studies. To ensure accurate estimates, data approximation in figures was avoided. Where there was missing data or undetermined information, attempts were made to contact the first or corresponding author of the included publications for clarification or to retrieve additional data. Disagreements concerning data extraction were resolved by discussion and consensus.

2.6.2. Data Analysis

For primary data analysis, a weighted mean based on the number of participants and its standard deviation (SD) was calculated, along with a 95% confidence interval (CI) for average brushing time. Based on toothbrush type, ‘a priori’ subgroups of manual or powered toothbrush users were defined. A scatter plot was generated to visually assess the relationship between brushing duration (in seconds) and publication year. A linear regression was incorporated to quantify this relationship, with the R ² value indicating its strength and direction. An R ² value that is greater than zero indicates a positive relationship. A value that is less than zero signifies a negative relationship. Finally, a value of zero indicates no relationship between the two variables [31]. All data analyses were performed using SPSS 30.0 (SPSS Inc., Chicago, IL, USA).

2.7. Grading the Body of Evidence

The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system, as proposed by the GRADE working group [32], was used to rank the body of evidence emerging from this review. Two reviewers (YSRH & DES) rated the quality of the evidence and the strength of the recommendations [33].

3. Results

3.1. Search and Selection

After searching the MEDLINE‐PubMed and Cochrane‐CENTRAL databases, 3287 unique papers were identified (see Figure 1). Screening of titles and abstracts resulted in 52 papers that potentially met the inclusion criteria. The full texts of these selected studies were obtained and reviewed in detail, leading to the exclusion of an additional 40 papers. The reasons for exclusion are provided in Appendix S1. Ultimately, 12 studies [34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45] were identified for inclusion. Of these, three [37, 43, 45] contained multiple evaluations, resulting in 16 evaluations for analysis.

FIGURE 1.

Flow chart. Search and selection results.

3.2. Assessment of Methodological Heterogeneity

All included studies were observational. Two studies (VI [35], VII [42]) employed a cross‐over design, nine (I‐V [36, 39, 40, 44, 45], VII [42], IX [37], XI [34]) used a cross‐sectional design, and one (VIII [38]) used a cohort design. All 12 studies included the use of an MTB, and two of these studies (IX [37], XII [43]) also used a PTB. All studies that included a PTB utilized models with an oscillating‐rotating brush head design.

3.3. Assessment of Clinical Heterogeneity

The characteristics of the included studies are summarized in Appendix S2. With the exception of one (VIII [38]), all studies were conducted in Europe. The number of participants varied from 14 to 300. In three of the studies (VII–IX [37, 38, 42]) participants used their own toothbrushes, irrespective of toothbrush type. In seven studies (I [36], II [40], IV [44], VI [35], X–XII [34, 41, 43]), the toothbrushes were provided by the researchers. In two studies (III [39], V [45]), it was unclear whether participants used their own toothbrushes or the researchers provided them. In most of the studies (I [36], III [39], IV [44], VII [42], X–XII [34, 41, 43]), participants performed the brushing exercise in front of a mirror. In one study (II [40]), the exercise did not involve a mirror, while in one third of the studies (V [45], VI [35], VIII [38], IX [37]), mirror use was unspecified. In more than half of the studies (III [39], IV [44], VII [42], VIII [38], X [41], XI [34]), participants were aware of being filmed. In two of the studies (II [40], V [45]), participants were unaware of being watched, filmed and/or timed, while four studies (I [36], VII [42], IX [37], XII [43]) did not mention this detail. In half of the studies, researchers did not provide (XI [34], XII [43]) or specify (III [39], VI–VIII [35, 38, 42]) the use of dentifrice during the single brushing exercise. In the other six studies, participants were provided with dentifrice, although not all studies specified the brand used.

3.4. Assessment of Methodological Quality

A summary of the evaluation of the risk of bias in the individual studies is provided in Appendix S3. Across studies, the reporting on blinding procedures was often unclear or inconclusive. In addition, toothbrushing duration was frequently measured while participants and/or outcome assessors were aware of the intervention being delivered. This lack of blinding may have affected the measurement of outcomes, which contributed to the consistent judgment of moderate risk in this domain.

3.5. Study Outcome Results

3.5.1. Primary Outcome; Mean Brushing Time

Table 2a, 2b presents the results of the data extraction of the included studies for MTB (Table 2a) and PTB (Table 2b) separately. The shortest average brushing time observed was 33 s, while the longest was 158 s.

TABLE 2a.

Mean brushing time in seconds (SD) for participants using an MTB of the included studies.

ID	Study	Subjects (N)	Mean brushing time in seconds (SD)
I.	Rugg‐Gunn and Macgregor, 1978	30	39.1 (16.6)
II.	Macgregor and Rugg‐Gunn, 1984	128	60.1 (?)
III.	Macgregor et al., 1985	60	33.0 (12.0)
IV.	Macgregor & Rugg‐Gunn, 1986	50	32.8 (?)
V‐1.	Saxer et al., 1998	138	68.6 (34.0)
V‐2.	Saxer et al., 1998	68	83.5 (32.9)
V‐3.	Saxer et al., 1998	94	72.8 (35.0)
VI	Schäfer et al., 2003	19	73.4 (31)
VII.	Ganss et al., 2009	103	96.6 (36.0)
VIII.	Hunter et al., 2012	14	54 (?)
IX.	Rosema et al., 2014	90	114.5 (?)
X.	Harnacke et al., 2015	70	100.6 (56.0)
XI.	Winterfield et al., 2015	101	156.0 (71.1)
XII.	Ganss et al., 2018	95	135 (?)

Note: ? = Unknown/not given.

TABLE 2b.

Mean brushing time in seconds (SD) for participants using a PTB of the included studies.

ID	Study	Subjects (N)	Mean brushing time (SD) in seconds
IV.	Rosema et al., 2014	91	157.5 (?)
X.	Ganss et al., 2018	95	145 (?)

Note: ? = Unknown/not given.

Table 3 displays the overall average brushing duration in adults, based on a weighted mean across all studies totaling 1246 participants. This average was 96.8 s with a 95% CI: [77.10; 116.50]. The sub‐analysis based on the type of toothbrush showed that the average brushing times were 87.3 (95% CI: [68.50; 106.10]) for MTB and 151.1 (95% CI: [142.37; 159.83]) seconds for PTB toothbrushing exercises. The corresponding 95% CIs do not overlap, indicating a statistically significant difference.

TABLE 3.

Summary of weighted mean brushing time (SD) and 95% confidence interval (CI) for MTB and PTB users, presented separately by toothbrush type and combined overall.

Type of brush	Subjects (N)	Evaluations (N)	Seconds (SD)	95% CI
MTB	1060	14	87.3 (35.9)	[68.50; 106.10]
PTB	186	2	151.1 (6.3)	[142.37; 159.83]
Cumulative/Overall	1246	16	96.8 (40.2)	[77.10; 116.50]

3.5.2. Secondary Outcome; Brushing Duration Related to Publication Year

Figure 2 illustrates the scatter plot with an incorporated linear regression, which examines the correlation between brushing duration (in seconds) and the year of publication for MTB users. The regression line shows a positive trend over the publication year, suggesting that manual brushing time increases as time progresses. The R ² value of 0.522 indicates that approximately 52% of the variability in brushing duration can be explained by the publication year, demonstrating a moderate relationship (see Appendix S4) [31]. A regression analysis on PTB could not be conducted as only two evaluations were included in the dataset. The small number of data points does not meet the minimum requirements for a reliable regression analysis.

FIGURE 2.

Correlation between publication year and manual toothbrushing duration in seconds.

3.6. Evidence Profile

Table 4 shows the evidence profile based on a summary of the various factors used to rate the quality of evidence and the level of certainty. It accumulates into an estimation of the strength and direction of the recommendation according to GRADE [32, 33]. With moderate certainty, the average brushing time of uninstructed adults using an MTB appeared to be approximately one and a half minutes, and for powered toothbrush users, this was more than 2 min. Manual toothbrushing duration appears to have increased over the years as publications on this topic have emerged.

TABLE 4.

GRADE evidence profile. Summary of findings table on body of the estimated evidence profile and appraisal of certainty, the strength and the direction of the recommendation regarding brushing time.

GRADE evidence profile	Outcome MTB	Outcome PTB
Number of included studies (Figure 1)	N = 12	N = 2
Number of included toothbrushing exercise experiments (Figure 1)	N = 14	N = 2
Study design (Appendix S2)	Cross‐sectional, cross‐over, RCT	Cross‐sectional
Risk of bias (Appendix S3)	Moderate	Moderate
Consistency (Table 2a, 2b, Figure 2)	Rather inconsistent	Rather inconsistent
Precision (Table 3)	Rather precise	Rather precise
Directness	Rather generalizable	Rather generalizable
Publication bias	Possible	Possible
Body of evidence	Moderate	Limited
Summary of the certainty and magnitude of the findings	With moderate certainty the average manual toothbrushing duration among adults is 1.5 min	With moderate certainty the average powered toothbrushing duration among adults is more than 2 min

The Supplementary appendix contains: (1) details on excluded studies, (2) characteristics of included studies, (3) ROBINS‐I risk‐of‐bias assessments, and (4) guidelines for interpreting correlation coefficients.

4. Discussion

4.1. Summary of Key Findings

This systematic review provides insights into the average brushing time among adults. The findings indicate that uninstructed individuals aged 18 and older brush their teeth with an MTB for an average of 87 s during a single brushing exercise, which falls short of the recommended 2 min minimum toothbrushing time recommended for maintaining good oral health [19, 20, 21]. Furthermore, the results show that PTB users brush significantly longer than MTB users on average, surpassing the 2 min recommendation. The difference between MTB and PTB of over a minute seems clinically relevant. Additionally, PTB users on average exceed the recommended 2‐min brushing time, whereas MTB users fall short. Secondary outcomes reveal a positive trend with moderate strength over the years of publication, indicating that manual toothbrushing time has increased over time.

4.2. Duration and Effectiveness

In a study by Van der Weijden et al. [46], which examined the effect of brushing time on plaque removal by professional brushing with MTBs and PTBs, five brushing durations were tested: 30, 60, 120, 180, and 360 s [46]. Results indicated that 2 min of electric toothbrushing achieved similar plaque removal to 6 min of manual brushing. The authors also noted that both manual and electric toothbrushes reached an optimal level of plaque‐removing efficacy at 2 min. A systematic review by Seuntjens et al. [47] supported this finding, concluding with moderate certainty that 2 min of brushing is more effective than 1 min for plaque removal. However, extending brushing time from two to 3 min seems not to contribute to an additional benefit. This evidence points to an optimal brushing duration of 2 min, as further supported by sub‐analyses from Slot et al. [16] and Rosema et al. [17]. Although brushing time is likely the most easily controlled parameter of effective everyday brushing, effectiveness can be influenced by other variables, such as the type of toothbrush used [13], bristle tuft configuration [48], filament design [49], brushing technique [50], instruction [51], and manual dexterity [52]. A recent consensus recommendation report of the FDI World Dental Association (FDI) stated that teeth should be brushed for long enough to ensure all surfaces are cleaned effectively. It has been suggested that the achievement of effective cleaning is more critical than adherence to a specific brushing duration [18].

4.3. Trends in Tooth Brushing Practices and Public Awareness

The increasing duration of tooth brushing over time suggests a gradual shift towards more thorough oral hygiene practices, probably influenced by evolving guidelines and heightened public awareness of oral health. A recent study from Denmark [53] reported significant improvements in oral health, including increased dental visits, a decline in the number of edentulous individuals, and better retention of natural teeth, as well as a decrease in periodontal diseases. However, the study also highlighted that the frequency of dental check‐ups remains relatively low and irregular, which may be attributed to factors such as healthcare system limitations, personal financial constraints, and a lack of patient knowledge or motivation. Historically, dental care has been reactive and symptom‐driven [54, 55], but there has been a notable shift towards preventive dentistry in recent decades, supported by changes in dental education programs aligned with European frameworks [56, 57]. The World Health Organization (WHO) has further advanced this focus through its global oral health action plan, recognizing oral diseases as significant global health burdens that share common risk factors with other noncommunicable diseases [58]. Action 33 of this plan emphasizes strengthening personal, social, and political skills in oral health, promoting practices such as twice‐daily brushing with fluoride toothpaste. These initiatives, combined with the widespread availability of online information, have increased public awareness of oral health. Despite this progress, a recent PhD study analysing dental care organization websites found inconclusive information regarding recommended brushing times [59]. This finding highlights the desire for standardized guidelines and clear communication on optimal brushing duration, individualized to ensure effective oral hygiene practices.

4.4. Study Limitations and Suggestions for Future Research

In the present systematic review only adults were included but also children form a considerable part of the general population. Although they have temporary, mixed or permanent dentition and they can either brush alone, supervised or assisted, it seems of interest to evaluate brushing times among this specific group in a separate review. Additionally, dental care professionals and students were excluded from this review due to their dental knowledge, which could introduce bias in several ways. First, these individuals typically possess an advanced understanding of oral hygiene practices and dental care. Their familiarity with optimum toothbrushing techniques and recommended durations, and their awareness of the risks associated with poor oral hygiene, including dental caries and periodontal disease, could lead to more rigorous brushing habits compared to the average adult. The difference in behaviour could introduce a selection bias, affecting the overall findings of the review and limiting the applicability of the results to the wider community. Therefore, excluding this group helps ensure the data more accurately reflect the toothbrushing habits and oral health behaviours of the general population [60].

Individuals' exact number of teeth can vary due to oral health issues or genetic factors. It can be assumed that individuals with significantly fewer teeth tend to spend less time brushing. However, the number of teeth of the participants in the elected studies reviewed is unclear. For future research, it would be beneficial to better define the study population to enable sub‐analyses.

In addition, this study did not explore potential differences in toothbrushing duration between middle aged and older adults, particularly in relation to age related declines in manual dexterity. As reduced dexterity likely affects brushing quality more than duration, which was the focus of the present study, meaningful subgroup analyses were not feasible. Future large scale cross sectional research is needed to examine how age related changes in dexterity may influence toothbrushing behaviour.

The current systematic review revealed differences in the populations studied. With the exception of one, all studies were conducted in Europe. Considering the availability of multiple national databases, it would be valuable to explore the correlation between evaluated brushing time and dental outcome parameters across diverse populations worldwide. Differences in cultural practices, socio‐economic status, and healthcare access may influence these outcomes, underscoring the need for a broader, more inclusive analysis.

Another potential limitation of the present study is that certain aspects of the brushing environment may have influenced toothbrushing behaviour. The presence of a mirror may affect toothbrushing behaviour. This visual feedback can potentially increase brushing thoroughness or modify technique, potentially influencing both duration and coverage. However, whether this leads to longer or shorter brushing times is variable and may depend on individual habits. In addition, an RCT evaluating a smart toothbrush and mirror (STM) system showed that adding technologically enhanced visual feedback did not result in greater plaque reduction compared to conventional verbal instruction [61]. This suggests that while mirrors or visual guidance may support technique learning, their added value beyond standard instruction in terms of measurable oral‐hygiene outcomes remains limited.

The use of toothpaste may also indirectly influence brushing duration, as sensorial properties such as taste, flavour, and foaming can shape the perceived completeness of cleaning and may motivate individuals to brush slightly longer. Moreover, brushing with toothpaste is generally experienced as more pleasant than brushing without it, which could further enhance brushing engagement [8, 62, 63]. However, the extent to which these sensorial factors influenced brushing duration in the included studies remains difficult to ascertain.

A further consideration is the distinction between naturalistic and best‐case scenario brushing. Naturalistic brushing reflects behaviour in everyday, unsupervised home settings, which is often shorter than recommended, while best‐case scenario brushing occurs in controlled or supervised environments where participants are instructed or motivated to follow recommended techniques and durations. Recognizing this difference is important, as outcomes observed in supervised studies may not fully represent habitual, real‐world brushing behaviour [64, 65, 66].

One selection criterion for this study was that brushing times had to be measured using a timer. However, this methodology may introduce a significant bias known as the Hawthorne effect [60, 67, 68]. This effect occurs when individuals alter their behaviour because they are being observed, rather than due to any inherent change in their routine or practices. In the context of this study, participants who were aware that their brushing duration was being timed or recorded might have felt inclined to brush for longer than they typically would in their daily lives. The potential for the Hawthorne effect in this review needs to be acknowledged when interpreting the results and understanding the limitations inherent in measuring self‐care practices like toothbrushing duration.

Given the substantial clinical heterogeneity observed across studies, future research on brushing time would benefit from greater standardization of study procedures. This includes the use of consistent and validated methods to measure brushing duration, preferably collected in a blinded or automated manner. For example, objective, individual‐level, and ecologically valid data can be obtained directly from smart powered toothbrushes, such as those used in the Remote Oral Behaviours Assessment System (ROBAS), which capture brushing timing, duration, and pressure applied through embedded sensors [69].

Clear reporting of blinding procedures, participant instructions, and device settings is also important. Such methodological improvements would enhance comparability between studies and support more reliable conclusions about brushing time and its effects.

5. Conclusions

Within the limitations of the present study design, there is moderate certainty that the average toothbrushing duration among uninstructed adults when using an MTB is approximately one and a half minutes, with evidence suggesting an increase in brushing duration over the years. This duration falls short of the recommended guidelines, whereas PTB users brush for over 2 min on average.

6. Clinical Relevance

6.1. Scientific Rationale for the Study

The American Dental Association (ADA), FDI World Dental Association (FDI), and European Federation of Periodontology (EFP) recommend brushing for 2 min 2× daily. This article examines the potential gap between these guidelines and actual brushing times.

6.2. Principal Findings

Based on single brushing exercises adults brush their teeth with a manual toothbrush (MTB) on average close to 1,5 min. With moderate strength of evidence, toothbrushing duration appears to increase over time.

6.3. Practical Implications

Dental care professionals (DCPs) should emphasize the importance of brushing time, especially for MTB users, even though an improvement over time has been observed. Evidence suggests that powered toothbrushes (PTBs) help promote longer brushing durations.

Author Contributions

All authors approved the final version of this manuscript before submission and agreed to be accountable for all aspects of the work, ensuring that questions related to the accuracy or integrity of any part of the work were appropriately addressed and resolved. T.M.J.A.T.: contributed to conception and design, search and selection, analysis and interpretation, and drafted the manuscript. Y.S.R.H.: contributed to the design, search and selection, analysis and interpretation, and drafted the manuscript. F.A.W.: contributed to the analysis and interpretation, and critically revised the manuscript. D.E.S.: contributed to conception and design, search and selection, analysis and interpretation, and critically revised the manuscript.

Funding

The research team of Van der Weijden and Slot at ACTA has previously received either external advisor fees, lecturer fees or research grants from oral health care manufacturers. Those manufacturers included Colgate, Dentaid, GABA, Lactona, Oral‐B, Procter & Gamble, Sara Lee, Sunstar, TePe, Unilever & Water Pik.

Conflicts of Interest

This paper was prepared to fulfil the co‐author YSRH's requirements for a master's degree in dentistry at ACTA Amsterdam. The investigators declare that they have no conflicts of interest. Van der Weijden is the owner of Jardin B.V., which is the former owner of www.ragershop.com (a webshop for various brands of interdental brushes).

Supporting information

Appendix S1: Papers excluded after full text reading with the details of rejection.

Appendix S2: Overview of the included studies and characteristics processed for data extraction.

Appendix S3: Assessment of the Risk of Bias using the ROBINS‐I Tool.

Appendix S4: Guidelines for interpreting correlation coefficients according to Blaine (2023).

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.