Plaque removal using powered and manual toothbrushes in children with and without attention deficit hyperactivity disorder: a randomized controlled trial

Abstract

Objectives

To evaluate the effectiveness of powered versus manual toothbrushes in plaque removal among children with and without Attention Deficit Hyperactivity Disorder (ADHD).

Materials and methods

Fifty-two children aged 8–10 years (26 with ADHD, 26 controls) were randomly assigned to powered or manual toothbrush groups. All received standardized instruction. Plaque and gingival health were assessed using the Turesky-modified Quigley-Hein Plaque Index (TQHPI), Approximal Plaque Index (API), and Löe-Silness Gingival Index (GI), recorded before and after supervised brushing, and at 1- and 3-month follow-ups. Children brushed at home twice daily. Mann–Whitney, Wilcoxon, and Friedman tests were used (p ≤ 0.05).

Results

Mean age was 8.8 ± 0.7 years. Supervised single brushing significantly reduced TQHPI and API in all subgroups (p < 0.05), with no differences by brush type or ADHD status (p ≥ 0.05). In the Control-powered group, API improved over time (p = 0.02), suggesting a familiarization effect during home use. No such trend was observed in the manual or ADHD subgroups. At 3 months, GI scores were higher in ADHD-powered than ADHD-manual users (p = 0.01).

Conclusions

Both brush types were similarly effective for immediate plaque removal in children with and without ADHD. During home use, powered brushes improved approximal outcomes in healthy children but not in those with ADHD, who showed poorer gingival outcomes.

Clinical relevance

In 8–10-year-old children, powered and manual toothbrushes demonstrated comparable plaque and gingival outcomes under standardized instruction. Familiarization may improve approximal plaque removal in healthy children using powered brushes. In children with ADHD, manual brushes yielded more favorable gingival scores, suggesting that effective use of powered brushes may require additional support.

Trial registration

ClinicalTrials.gov (NCT05935254) registered retrospectively on 7 July 2023. URL https://clinicaltrials.gov/study/NCT05935254.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-026-07881-y.

Introduction

Attention Deficit Hyperactivity Disorder (ADHD) is the most common neurodevelopmental disorder of childhood, characterized by persistent patterns of inattention, hyperactivity, and impulsivity. These behavioral features significantly impair the ability of affected children to consistently perform daily health-related routines, including toothbrushing. Children with ADHD often exhibit poor oral hygiene habits, such as reduced brushing frequency and shorter brushing duration, which contribute to higher plaque levels and an increased risk for dental caries and gingivitis [1, 2]. In addition, deficits in self-regulation often lead to more frequent sugar-rich snacking, further increasing oral health risks [3]. Studies have reported that children with ADHD present with poorer plaque control and gingival health compared to their neurotypical peers [2, 4].

Mechanical plaque removal remains the foundation of caries and gingivitis prevention. This advantage has also been consistently observed across diverse pediatric populations. Several studies and systematic reviews have demonstrated that powered toothbrushes are more effective than manual brushes in reducing plaque and improving gingival health in children [5–9]. This superiority is particularly notable in populations with physical or cognitive impairments, where powered toothbrushes can help compensate for limitations in motor coordination and attention span [10–13]. Qualitative research also indicates that parents often perceive powered toothbrushes as helpful in overcoming young children’s resistance to toothbrushing and in facilitating daily oral hygiene routines [14].

Despite existing evidence on the benefits of powered toothbrushes [14], no randomized controlled trial has directly compared their plaque-removal efficacy to that of manual toothbrushes in children with ADHD. To address this gap, the present parallel-group randomized trial includes children with and without ADHD, assessing immediate plaque reduction following a single supervised brushing session and long-term effectiveness after 1- and 3-month periods of home use. Given the reduced attention span, shorter brushing duration, and higher plaque accumulation typically observed in children with ADHD [10–13], it is hypothesized that powered toothbrushes will result in greater plaque reduction compared to manual toothbrushes, with a more pronounced effect in the ADHD group.

Materials and methods

Ethical approval

This study was conducted in accordance with the Declaration of Helsinki. Ethical approval was granted by the Aydın Adnan Menderes University Faculty of Dentistry Clinical Research Ethics Board (Decision No: 04, 16.06.2021) (Appendix 1). The study enrollment period extended from January to December 2022. Informed consent was obtained from all children and their guardians (Appendices 2, 3). The trial was retrospectively registered on ClinicalTrials.gov (Identifier: NCT05935254) on 1 July 2023.

Study design

This study was designed as a randomized, controlled, single-blind clinical trial in accordance with the 2025-CONSORT guidelines [15]. The study flow diagram is presented in Fig. 1.

Fig. 1.

Flowchart of the study

Sample size calculation

The sample size was calculated using G-Power software (version 3.1.9.4). Based on a previously published article [16], the common standard deviation was determined to be 0.639, and the effect size was calculated as 0.393. Using these values, a total sample size of 52 participants was determined, with 13 participants in each of the four subgroups. Calculations were performed with a power of 0.8 and a Type I error rate of 0.05.

Participants and inclusion criteria

Children aged 8–10 years were included if they had at least 16 teeth, no oral prophylaxis or antibiotic use in the past month, no prior use of powered toothbrushes, no severe periodontal disease or painful caries, and no orthodontic appliances. Children with complex medical conditions or other psychiatric diagnoses were excluded.

Study groups and randomization

Two primary groups were included in the study. The ADHD group consisted of children who had been formally diagnosed with attention-deficit/hyperactivity disorder (ADHD) according to DSM-5 criteria by pediatric psychiatrists prior to enrollment [17]. The control group comprised healthy children attending the Pediatric Dentistry Clinic of Aydın Adnan Menderes University Faculty of Dentistry, with no reported history or diagnosis of ADHD or other neurodevelopmental conditions, confirmed through parent-reported medical history.

Children were first assigned to ADHD or Control groups based on prior clinical diagnosis. Random allocation was performed within each group (ADHD and Control) to assign participants to either powered or manual toothbrush subgroups. A simple randomization sequence was generated using Random.org (Randomness and Integrity Services Ltd., Ireland). Allocation was implemented by the same clinician (B.M.A.), who was not involved in outcome assessment. Group assignments were concealed from the examiner to maintain blinding.

Interventions

Participants received standardized training from the same clinician (B.M.A), including hands-on practice with a training toothbrush of the assigned type. Toothbrushes were pediatric-sized and soft-bristled in both groups, with comparable brush head dimensions. Caregivers were not required to demonstrate the technique but were present during training and instructed on home supervision.

• Manual group: A soft-bristled manual brush (Oral-B Stages, 6–12 years; Procter & Gamble, USA) was used. The Bass technique was demonstrated on a typodont.

• Powered group: A powered brush with a pediatric round head (Oral-B Kids D100; Procter & Gamble, USA) was used, following manufacturer instructions.

Following training, each child received a new toothbrush according to the assigned group for both clinical and home use after the baseline measurements (T0a), along with a pea sized amount of toothpaste (Sensodyne Pronamel Kids; GlaxoSmithKline Brazil Ltda, Rio de Janeiro, Brazil). A two-minute sand timer and brushing schedule were provided to encourage routine adherence and parental involvement but were not reviewed for outcome assessment. Children were instructed to brush twice daily for two minutes using the trained technique, under parental supervision. No formal behavioral support was provided to ADHD participants beyond routine parental guidance. The protocol assessed single-brushing efficacy (pre- to post-brushing change per visit) and home-brushing effectiveness (pre-brushing score changes across baseline, 1-month, and 3-month visits).

At each visit (baseline, 1 month, 3 months), a plaque-disclosing agent (Mira-2-Ton; Hager Werken, Germany) was applied pre- and post-brushing to all labial and lingual surfaces using a microbrush (~ 1.0 mL), left for 30 s, then rinsed with water for 30 s. Participants brushed for two minutes with their assigned toothbrush, standing in front of a mirror without assistance, under supervision by an independent dentist. Red protective glasses were worn to reduce disclosing-agent exposure and minimize distraction from stained plaque.

To standardize baseline conditions, participants were instructed not to brush for 24 h and to avoid eating or drinking for 4 h before the baseline visit only [18]. These restrictions were not applied at 1- or 3-month visits; thus, pre-brushing plaque scores at follow-up reflect home-care routines.

Outcome measurements

Sociodemographic features and oral health related habits

A questionnaire consisting of 17 items was administered to participating children with the assistance of their parents. It addressed sociodemographic factors, as well as the children’s dietary habits, nutritional intake, and toothbrushing practices (Appendix 4).

Primary outcome measurements

Plaque-removal efficacy was assessed using the Turesky modification of the Quigley–Hein Plaque Index (TQHPI) and the Approximal Plaque Index (API). Measurements were obtained at baseline (T0), 1 month (T1), and 3 months (T2), both before supervised brushing (pre-brushing, a) and after supervised brushing (post-brushing, b).

All examinations were performed under standardized clinical conditions, with adequate illumination, using a plane dental mirror and a WHO periodontal probe. A single examiner (Z.U.), trained and calibrated with clinical reference images and a pilot group (n = 10), conducted all assessments and was blinded to group allocation. Intra-examiner reliability was tested by repeating measurements one week later; Cohen’s kappa was 0.86 for TQHPI and 0.88 for API, indicating substantial agreement.

The buccal and lingual surfaces of each tooth were divided into mesial, central, and distal regions and scored from 0 to 5 for plaque intensity. The mean of the six scores per tooth was used to calculate the TQHPI [19, 20].

Approximal surfaces in quadrants 1 and 3 were examined from the lingual aspect, and those in quadrants 2 and 4 from the buccal, following Lange et al. [21]. Plaque was recorded as “present” or “absent.” API was calculated as the percentage of plaque-positive sites among all examined approximal surfaces.

Secondary outcome measurements

The Löe-Silness Gingival Index was used to assess gingival inflammation. Examinations were conducted at baseline (T0a), 1 month (T1a), and 3 months (T2a) prior to brushing, using standardized WHO diagnostic criteria and tools. Each tooth was scored in four regions (buccal, mesial, distal, and lingual) on a scale from 0 (normal) to 3 (severe inflammation). The mean of these scores per tooth was averaged across all teeth to calculate the overall index [22].

Statistical analysis

Statistical analysis was conducted using SPSS 17.0 for Windows (SPSS Inc., Chicago, IL, USA). All data were anonymized and stored in password-protected electronic files accessible only to the examiner and statistician. Normality of data distribution was assessed using the Shapiro-Wilk test, and homogeneity of variances was evaluated. Descriptive statistics included frequencies, percentages, medians, interquartile ranges (25th -75th percentiles), and 95% confidence intervals. The chi-square test was used to assess associations between categorical variables in the ADHD and control groups. As the data were non-normally distributed, the Mann-Whitney U test was used for between-group comparisons. The Wilcoxon signed-rank test assessed single-brushing efficacy (pre- to post-brushing), while the Friedman test was used to evaluate changes across time points for home-brushing effectiveness. A Type I error threshold of 0.05 was considered statistically significant.

Results

A total of 72 children were enrolled: 15 declined participation and 5 missed baseline assessments. The final sample included 52 children (21 female, 31 male; mean age 8.8 ± 0.7 years, range: 8–10 years) who completed all follow-up visits (Fig. 2; CONSORT). No adverse effects related to brushing or clinical procedures were reported by participants or caregivers during the study. Sociodemographic data are shown in Supplementary Table 1. No significant differences were found between ADHD and control groups in age, gender, or parental education (p > 0.05). Among children with ADHD, 76.9% (n = 20) were on medication.

Fig. 2.

Consort diagram of the study

Oral hygiene habits

A statistically significant difference in brushing duration was observed: 69.3% of children in the control group brushed for ≥ 2 min, compared to 34.6% in the ADHD group (p = 0.01). Among powered toothbrush users, a greater proportion of children in the ADHD group brushed for ≤ 1 min than those in the control group (p = 0.02) (Supplementary Table 2).

TQHPI values

At each visit (T0, T1, T2), mean pre-brushing TQHPI scores were significantly higher than post-brushing scores across all subgroups (p < 0.05), indicating effective plaque removal following a single brushing session (Fig. 3). Mean differences (ΔT0a-T0b, ΔT1a-T1b, ΔT2a-T2b) did not significantly vary by brush type or group and remained stable across visits (all p > 0.05) (Table 1). For home brushing, mean pre-brushing TQHPI scores showed no significant between-group or between-brush differences at any visit, and no significant within-group changes over time (p > 0.05). Complete results are provided in Supplementary Table S3.

Fig. 3.

TQHPI and API Pre-Post Brushing Comparisons. Trajectories of TQHPI (top panels) and API (bottom panels) at baseline (T0), 1 month (T1), and 3 months (T2), shown separately for Control—Manual, Control—Powered, ADHD—Manual, and ADHD—Powered subgroups. Solid lines depict pre-brushing values; dashed lines depict post-brushing values. Points are medians; shaded bands represent 95% confidence intervals

Table 1.

TQHPI changes and comparisons of control and ADHD groups

	CONTROL				ADHD			Comparison between subgroups
		Manual	Powered		Manual	Powered		*p	**p
		50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p	50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p
Single Brushing	Δ T0a-T0b	23.56(16.74-34.41) (25.28-32.24)	27.15(9.54-40.64)(14.94-33.47)	1.00	23.30(16.97-41.56)(19.31-38.62)	31.04(18.37-38.63)(20.89-36.97)	0.57	0.72	0.57
	Δ T1a- T1b	24.35(15.31-31.59)(17.41-29.77)	18.89(13.99-36.49)(13.82-33.44)	0.53	26.07(23.24-29.85)(19.10-36.24)	24.63(12.68-30.59)(15.02-33.24)	0.41	0.72	0.85
	Δ T2a- T2b	31.94(21.17-44.77)(19.84-43.69)	27.16(21.13-40.31)(19.28-47.10)	0.57	33.02(24.75-43.40)(26.59-43.88)	22.69(19.08-31.78)(20.51-31.36)	0.06	0.80	0.54
	***p	0.12	0.47		0.23	0.71
Home Brushing	ΔT0a-T1a	6.59(-19.40-18.93)(-19.40-19.71)	-0.24(-13.52-23.39)(-15.51-31.48)	0.92	11.12(2.32-20.02)(-0.00-19.93)	8.03(-23.39-29.08)(-11.48-21.03)	0.65	0.44	0.97
	ΔT0a-T2a	13.18(-16.63-24.30)(-15.60-23.44)	8.92(-24.75-41.51)(-68.26-41.89)	0.76	19.49(-8.94-33.65)(-6.71-27.44)	26.34(-28.46-41.94)(-11.53-32.49)	0.61	0.61	0.97
	ΔT1a-T2a	11.15(-25.79-18.28)(-26.66-21.64)	11.31(-20.64-29.37)(-11.54-27.41)	0.50	11.15(-24.04-11.86)(-18.41-17.20)	4.54(-3.90-16.59)(-3.09-17.24)	0.96	0.92	0.93
	***p	0.36	0.77		0.09	0.92

T0a/b: Baseline pre-/post-brushing, T1a/b: 1-month pre-/post-brushing, T2a/b: 3-month pre-/post-brushing

Δ: Change between time points

p: Comparison between manual vs powered, *p: Manual toothbrush subgroups comparison (Control vs ADHD), **p: Powered toothbrush subgroups comparison (Control vs ADHD) (Mann–Whitney U test was used for the comparisons), ***p: Intra-subgroups comparison between different time points (Friedman test was used for the comparisons)

API values

At all visits (T0, T1, T2), pre-brushing API values were significantly higher than post-brushing in all subgroups (p < 0.05), confirming effective single brushing (Fig. 3). No significant differences in mean API reduction (ΔT0a-T0b, ΔT1a-T1b, ΔT2a-T2b) were found between brush types or groups, except in Control–powered, where the 3-month reduction exceeded baseline (p = 0.02). For home brushing, no significant pre-brushing differences were observed between brush types or groups (Table 2). ADHD–manual showed a significant pre-brushing API reduction from baseline to 3 months (p = 0.001), while ADHD-powered showed no change (p = 0.17). Full values are in Supplementary Table S4.

Table 2.

API changes and comparisons for control and ADHD groups

		CONTROL			ADHD			Comparison between subgroups
		Manual	Powered		Manual	Powered		*p	**p
		50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p	50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p
Single Brushing	Δ T0a-T0b	10.14(0.00-25.63)(4.86-29.25)	0.00(0.00-26.95)(-0.37-27.36)	0.33	22.82(5.00-39.42)(12.07-40.21)	12.00(5.66-28.16)(7.26-34.12)	0.47	0.31	0.07
	Δ T1a- T1b	16.00(0.00-24.97)(7.33-25.78)	14.00(0.00-32.50)(6.11-34.35)	0.88	20.21(4.89-38.50)(11.20-33.49)	14.77(0.00-22.50)(6.19-23.09)	0.33	0.44	0.80
	Δ T2a- T2b	21.95(12.71-40.19)(16.79-35.21)	29.00(11.36-50.18)(17.26-41.81)	0.54	25.00(7.39-38.10)(13.35-32.60)	24.24(5.00-60.06)(13.57-46.69)	0.84	0.54	0.72
	***p	0.31	0.02		0.68	0.38
Home Brushing	ΔT0a-T1a	0.00(-13.43-12.90)(-9.34-10.70)	0.00(-4.14-10.00)(-8.27-10.30)	0.84	6.00(-1.17-11.52)(-7.38-12.70)	0.00(-3.57-13.81)(-7.35-11.03)	0.67	0.72	0.80
	ΔT0a-T2a	8.88(-10.55-22.62)(-4.62-19.65)	0.00(-13.79-1.11)(-41.36-19.94)	0.20	18.00(9.66-25.00)(8.10-26.49)	8.00(-3.19-29.50)(-2.64-22.88)	0.36	0.24	0.24
	ΔT1a-T2a	1.21(-14.06-24.08)(-5.95-17.64)	0.00(-9.20-5.01)(-40.13-17.69)	0.47	16.66(2.68-20.10)(2.67-24.44)	3.61(0.00-15.80)(-1.31-18.06)	0.31	0.51	0.18
	***p	0.57	0.97		0.02	0.12

T0a/b: Baseline pre-/post-brushing, T1a/b: 1-month pre-/post-brushing, T2a/b: 3-month pre-/post-brushing

Δ: Change between time points

p: Comparison between manual vs powered, *p: Manual toothbrush subgroups comparison (Control vs ADHD), **p: Powered toothbrush subgroups comparison (Control vs ADHD) (Mann–Whitney U test was used for the comparisons), ***p: Intra-subgroups comparison between different time points (Friedman test was used for the comparisons)

Gingival index (GI) measurements

In the Control group, GI values were similar between brush types at all time points and stable over time (p > 0.05). In the ADHD group, no difference was found at baseline or 1 month, but GI was higher in the powered subgroup at 3 months (p = 0.01). GI change percentages did not differ between brush types within groups or between Control and ADHD manual users (p > 0.05). However, powered users in the Control group showed a greater GI reduction from baseline to 3 months than those in the ADHD group (p = 0.01) (Table 3).

Table 3.

Comparison of gingival index values and changes intra and inter groups

	CONTROL			ADHD			Comparison between subgroups
	Manual	Powered		Manual	Powered
	50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p	50p(25-75p)(%95 CI)	50p(25-75p)(%95 CI)	p	*p	**p
T0	1.15(0.87-1.28)(0.83-1.23)	1.16(1.07-1.36)(0.87-1.40)	0.47	0.97(0.89-1.12)(0.89-1.08)	1.11(0.93-1.25)(0.95-1.21)	0.15	0.31	0.44
T1	1.07(0.78-1.36)(0.77-1.42)	1.17(0.41-1.33)(0.59-1.22)	0.57	1.03(0.75-1.13)(0.83-1.09)	1.06(0.96-1.20)(0.93-1.22)	0.26	0.26	0.92
T2	1.08(0.72-1.25)(0.75-1.25)	0.95(0.53-1.24)(0.60-1.18)	0.47	0.78(0.63-0.95)(0.70-0.94)	1.01(0.96-1.26)(0.91-1.23)	0.01	0.11	0.26
***p	0.26	0.23		0.11	0.79
ΔT0-T1	-3.29(-65.20-25.49)(-75.98-29.11)	14.47(-5.82-43.91)(-1.93-45.22)	0.18	5.76(-11.16-21.64)(-15.92-17.66)	-1.40(-7.63-12.86)(-9.07-8.38)	0.65	0.72	0.13
ΔT0-T2	0.00(-36.33-29.61)(-47.06-30.86)	33.59(4.71-54.62)(5.20-54.72)	0.06	20.41(-0.65-35.95)(-0.05-29.54)	-3.52(-18.43-13.11)(-15.45-13.67)	0.11	0.31	0.01
ΔT1-T2	16.29(1.46-26.81)(-118.73-68.80)	12.40(-43.53-31.78)(-275.34-107.47)	0.57	17.10(-5.07-28.73)(-0.79-24.78)	-1.10(-10.33-9.62)(-18.17-14.16)	0.11	1.00	0.34
***p	0.38	0.33		0.50	0.73

T0: Baseline, T1: 1-month follow-up, T2: 3-month follow-up

Δ: Change between time points (e.g., ΔT0–T1 = T0 minus T1)

p: Comparison between manual vs powered, *p: Manual toothbrush subgroups comparison (Control vs ADHD), **p: Powered toothbrush subgroups comparison (Control vs ADHD) (Mann–Whitney U test was used for the comparisons), ***p: Intra-subgroups comparison between different time points (Friedman test was used for the comparisons)

Discussion

To our knowledge, this randomized trial is the first to compare plaque removal by powered and manual toothbrushes in children with and without ADHD. Using TQHPI, API, and GI to assess both single-brushing efficacy (within-visit change) and home-brushing effectiveness (pre-brushing change across baseline, 1 month, and 3 months), no statistically significant superiority of either toothbrush type was observed in either group. These findings do not support the hypothesis that powered toothbrushes provide greater plaque removal than manual toothbrushes in children with ADHD under the conditions tested.

Children with ADHD often experience difficulties with planning, self-regulation, and motor coordination, which can negatively affect oral hygiene behaviors and reduce the effectiveness of toothbrushing routines [23, 24]. Previous studies have shown that children and adolescents with ADHD tend to have poorer oral health indicators, such as higher plaque levels, increased caries prevalence, periodontal problems, and a greater incidence of dental trauma, compared to their non-ADHD peers. These outcomes are largely attributed to inconsistent oral hygiene routines and difficulties executing structured, effective brushing [2, 25]. While parental involvement is often necessary, particularly in younger children, the degree of assistance appears to vary with age. For example, Chau et al. [23] observed more frequent parental assistance in adolescents with ADHD, whereas Staberg et al. [26] found that children aged 8–19 years generally brushed independently, with more parental help reported in those under 8 years. In our study, which included children aged 8–10 years, a developmental stage where independent brushing is typically feasible due to improving manual dexterity all participants brushed independently, regardless of ADHD status [6, 27–29]. This may reflect the structured training and supervised brushing protocol used in our study, which emphasized consistent technique and routine. However, despite age-appropriate independence, previous research indicates that children with ADHD may still require continued behavioral support and caregiver supervision to maintain effective plaque control [25, 26], highlighting the need for tailored oral hygiene interventions in this population.

Evaluating single-brushing efficacy reflects immediate plaque removal under standardized conditions, similar to chairside instruction. In this trial, pre-brushing TQHPI scores were consistently higher than post-brushing scores at all visits across both ADHD and control groups, confirming effectiveness. Importantly, all baseline clinical indices (T0a) were recorded before any brushing instruction or demonstration. This ensured that the initial scores represented untreated oral hygiene status rather than the effects of early intervention. Recognizing this distinction is important for accurately interpreting the magnitude of immediate improvements and the stability of outcomes over time. However, no significant differences observed between brush types or groups, contrasting with studies reporting greater plaque reduction with powered brushes in children aged 3–12 years [5, 6, 16, 28, 30], but aligning with trials that found no significant differences between toothbrush types [31–36]. Differences in findings across the literature may reflect variations in brushing instruction, supervision, brushing duration, and toothbrush design. When technique and duration are standardized, as in this study, brush-type differences may narrow. Reported advantages of powered toothbrushes are often modest, limited to specific regions such as posterior or lingual surfaces, and influenced by factors including age, dentition stage, and the level of supervision. The high level of standardization in this study, particularly the two-minute brushing protocol and real-time supervision, likely reduced technique-related variability and minimized observable differences. Although this controlled design strengthens internal validity, it may limit generalizability to typical home-care settings.

Assessing home-brushing effectiveness reflects daily hygiene behaviors (including adherence, technique, and parental supervision) factors associated with caries and gingivitis risk. In this study, pre-brushing TQHPI scores at 1 and 3 months indicated routine plaque control. No significant differences were observed between powered and manual users, suggesting comparable effectiveness after standardized training. Although several short-term trials have reported improved plaque outcomes with powered toothbrushes [16, 28, 30, 35], other studies have found no clinically meaningful advantage over similar or longer durations [31–34, 36]. These inconsistencies may reflect heterogeneity in age (3–12 years), dentition stage, supervision, toothbrush design, and follow-up duration. In our 8–10-year-old sample under routine home care without adherence monitoring, technique quality and caregiver involvement appeared more influential than brush type. Baseline oral hygiene knowledge, brushing skills, and manual dexterity may also have influenced home-care performance—particularly in children with ADHD, where variability in attention and motor planning could affect brushing outcomes independently of toothbrush type. This variability may partly explain the largely comparable plaque and gingival outcomes observed between groups. The lack of significant difference between powered and manual brushes in the home-brushing condition may also reflect the high degree of standardization applied, including brushing duration, instruction, and supervision, which likely minimized technique-related variability.

Approximal surfaces tend to retain more plaque than buccal or lingual sites due to reduced accessibility during brushing [37]. In this study, API scores decreased significantly after a single supervised brushing in all subgroups, with no significant differences between them. This aligns with the limited interdental reach of bristles and the uniform 2-minute instruction applied across groups. A time-related trend was observed in the Control–Powered subgroup, where greater API reduction was achieved at follow-up visits compared to baseline, suggesting that brief familiarization with powered brush handling, vibration feedback, and tooth-by-tooth technique may enhance cleaning at approximal sites. No similar trend was observed in manual brush users or in children with ADHD.

During home care, assessed by pre-brushing API values at 1 and 3 months, no significant differences were found between brush types overall. Within the ADHD group, API values improved in the manual subgroup but remained stable in the powered subgroup, indicating that children with ADHD may find it easier to adapt to manual brushing, possibly due to better sensory tolerance or simpler motor demands. In contrast, powered toothbrushes may require extended familiarization and guidance, particularly in populations with attention and motor coordination challenges. The absence of a time-related improvement in the ADHD–Powered group may reflect difficulties in adapting to powered devices without sustained support. These findings align with previous pediatric studies: Doğan et al. [13] reported short-term API benefits with powered brushes in special-needs populations; Akgöl and Ulukapı [38] observed improvements over a five-month trial, emphasizing the role of instruction; Durhan et al. [39] found no consistent device advantage in a pilot study; and Srilakshmi et al. [40] reported superior API outcomes with sonic brushes only after extended use. Overall, interdental plaque control in 8–10-year-olds appears more dependent on brushing technique, adherence to routine, and caregiver supervision than on toothbrush type. Where powered brushes are used, especially in children with neurodevelopmental conditions, structured familiarization and ongoing behavioral support may be necessary to achieve measurable benefit.

Mechanical plaque removal by toothbrushing is the primary approach for preventing gingivitis. The 2014 Cochrane review found that powered toothbrushes reduced gingival index (GI) scores by around 6% in short-term use and 11% over longer durations, with oscillating–rotating models most supported [41]. In this study, children in the control group using powered toothbrushes showed greater GI reductions (14.47% at 1 month and 33.59% at 3 months). In contrast, GI slightly increased in the ADHD-powered subgroup. These results align with pediatric meta-analyses showing no significant gingival advantage for powered brushes in children, despite reported benefits for plaque reduction [42, 43]. However, short-term pediatric trials have reported greater GI improvements with powered brushes, particularly when caregiver support is present [12, 44]. The lack of improvement in the ADHD-powered group may reflect challenges brushing along the gingival margin, possibly due to sensory discomfort or inconsistent technique. These findings suggest that in 8–10-year-old children, gingival outcomes are influenced more by brushing behavior, supervision, and adherence to technique than by toothbrush type alone.

This randomized, examiner-blinded study used standardized training, a 2-minute supervised brushing protocol, and validated indices (TQHPI, API, GI), assessed by a calibrated examiner to ensure consistency. While these elements strengthen internal validity, some limitations remain. Motor coordination and sensory sensitivities, which may affect brushing performance, particularly in children with ADHD, were not assessed. Although intra-examiner reliability was high, plaque and gingival indices retain subjectivity. Home care adherence was not objectively tracked; brushing logs were incomplete, and unsupervised technique, interdental aid use, and diet were not systematically recorded.

Some limitations should be considered when interpreting the results. Brushing diaries were not collected or reviewed at follow-up appointments, as the primary focus was on clinical outcomes rather than behavioral tracking. While participants and caregivers received brushing schedules to encourage adherence, objective verification of home routines was not feasible. In addition, a validated screening tool was not used for control group participants; their neurodevelopmental status was based on parent-reported history, as formal psychiatric assessment was not part of the study protocol. These factors may affect the generalizability of behavioral findings and highlight areas for future research.

Although the power analysis ensured sufficient sample size to detect statistically significant effects, generalizability remains limited by the single-center design, narrow age range (8–10 years), and the specific toothbrush models used. Results may differ in other age groups, with alternative powered technologies, or under structured caregiver support. Clinically, findings emphasize that technique, supervision, and familiarity likely influence outcomes more than brush type. Future studies should incorporate longer follow-up, objective adherence monitoring, and behavioral and sensory assessments.

Conclusion

In this randomized trial of 8–10-year-old children with and without ADHD, supervised single brushing reduced plaque across all groups, with no significant differences between powered and manual toothbrushes in TQHPI, API, or GI scores. During the 1–3-month home brushing phase, children with ADHD demonstrated better gingival outcomes with manual brushes, which may reflect difficulty maintaining effective gingival contact with powered devices. Among healthy children using powered brushes, a modest improvement in approximal plaque scores over time may indicate increasing familiarity with the device. These findings suggest that powered brush effectiveness in children may depend on user adaptation. However, interpretation should consider study limitations, including the short follow-up duration, lack of objective adherence monitoring, and absence of structured behavioral support.

Authors’ contributions

All authors made substantial contributions to the conception and design of the study. (BMA) was responsible for project administration, participant training and clinical protocol implementation, supervision of clinic visits, and funding acquisition; BMA also contributed to data interpretation and critical revision of the manuscript. (ZU) coordinated participant enrollment and scheduling, performed all blinded clinical examinations and data collection, and drafted the manuscript. Both authors reviewed and edited manuscript drafts, approved the final version, and agree to be accountable for all aspects of the work.

Funding

This work was supported by Aydın Adnan Menderes University Scientific Research Projects (BAP), Project No. DHF-21008. The funder had no role in study design, data collection, analysis, interpretation, manuscript preparation, or the decision to submit.

Data availability

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

Declarations

Ethics approval and consent to participate

This study was conducted in accordance with the Declaration of Helsinki. Ethical approval was granted by the Aydın Adnan Menderes University Faculty of Dentistry Clinical Research Ethics Board (Decision No: 04, 16.06.2021). Informed consent was obtained from all children and their guardians.

Competing interests

The authors declare no competing interests.