Effectiveness of different types of toothbrushes on periodontal health in orthodontic patients with gingivitis: A randomized controlled study

Abstract

Background

The aim of the study is to evaluate the effectiveness of different toothbrushes in reducing gingival inflammation and dental biofilm removal in gingivitis patients with fixed orthodontic appliances.

Methods

Following baseline clinical assessments, including the Turesky modification of the Quigley-Hein plaque index (TQHI), gingival index (GI), bleeding on probing (BOP), and probing pocket depth (PPD), all patients received nonsurgical periodontal therapy. Patients were then randomly assigned to one of three groups: conventional toothbrush (C-TB), orthodontic toothbrush (O-TB), or single-tufted toothbrush (ST-TB). Each group received tailored oral hygiene instructions based on their assigned toothbrush type. Clinical assessments were repeated and recorded in the first week, sixth week, and third month.

Results

Thirty-six patients with a mean age of 23.14 ± 3.86 (18–32 years) participated in the study. All groups with twelve patients each demonstrated significant improvements in clinical parameters compared to baseline. In the sixth week, the O-TB and ST-TB groups showed significantly greater improvements in TQHI and BOP scores compared to the C-TB group (p < 0.05). By the third month, the ST-TB group maintained significantly lower TQHI and BOP scores, while the O-TB group’s scores became similar to those of the C-TB group. ST-TB and C-TB groups had significantly lower GI scores than the O-TB group in all time points. Although the effectiveness of ST-TB was significantly higher than that of other toothbrushes, all toothbrushes demonstrated lower efficacy in the posterior region.

Conclusions

The ST-TB was shown to be more effective in reducing gingival inflammation over three months, while it demonstrated similar efficacy to the O-TB in dental biofilm removal. Further research is necessary to substantiate these findings and to demonstrate the efficacy of this approach in promoting periodontal tissue health in patients with fixed orthodontic appliances.

Trial registration

This study was registered with the National Library of Medicine Clinical Trials Registry Platform on 19/07/2024 as NCT06510179.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-024-05084-x.

Background

Fixed orthodontic treatment is often the preferred method for the treatment of malocclusion and involves using complex devices like brackets and arch wires. These devices create areas that retain plaque, making effective plaque removal more challenging. Studies have shown that patients with fixed orthodontic appliances tend to have increased plaque accumulation [1, 2]. These patients are more susceptible to gingival inflammation due to this plaque-accumulating environment. The essential role of dental biofilm in gingivitis is well-documented, and removing biofilm can reverse the condition [3]. Previous animal studies on dentition with reduced periodontium have shown that orthodontic forces and tooth movements do not induce gingival inflammation without plaque [4–7]. However, in the presence of plaque, similar forces can result in vertical bone defects and attachment loss, especially with tipping and intruding movements [4]. Effective dental biofilm control is crucial for improving oral hygiene especially in orthodontic patients.

Orthodontic patients face challenges with mechanical plaque removal, requiring various strategies to control plaque formation, prevent gingivitis, and maintain the periodontal health [8]. Mechanical plaque removal with toothbrushes and interdental devices is the most common method for controlling plaque at home. Most patients prefer manual toothbrushes, whether conventional or orthodontic, due to their lower cost and ease of use. Although powered toothbrushes are more effective than manual ones in reducing plaque and gingivitis both short and long term in non-orthodontic patients, the effectiveness of powered versus manual toothbrushes is still uncertain for the orthodontic patients. A recent systematic review and meta-analysis concluded that there was no significant difference between manual and powered toothbrushes in reducing plaque accumulation or gingivitis in patients with fixed orthodontic devices [9]. Selecting oral hygiene instruments that are most appropriate for each patient’s specific needs is crucial for motivating orthodontic patients. Manual orthodontic toothbrushes have undergone advancements in bristle design and material. Many types of toothbrush options have been promoted for orthodontic patients. The use of orthodontic toothbrushes is currently preferred over other types of toothbrushes due to their bristle design, which makes it easier to clean the area around the brackets. Since orthodontic toothbrushes typically feature a V-shaped groove, while the shorter bristles within the groove are designed to clean the middle bracket area, the longer bristles are intended to clean the surroundings of the brackets. Studies comparing the effectiveness of orthodontic and conventional toothbrushes in reducing plaque and gingivitis on teeth with fixed appliances have shown conflicting results [8, 10–12]. More recently, single-tufted brushes have been investigated for their effectiveness in plaque removal. Single-tufted toothbrushes are recommended as an adjunctive device for surfaces and areas of the teeth that are not easily reached with other oral hygiene devices, such as the distal surfaces of molars, furcation areas, irregular gingival margins and areas of crowded teeth [13, 14]. Hasegawa et al., who first compared the effectiveness of single-tufted toothbrushes with the golden standard conventional toothbrush in controlling newly formed biofilm in the dentogingival area of healthy individuals, found it effective at controlling short-term dental biofilm neoformation on the dentogingival area [15].

There are limited studies comparing the plaque removal efficacy of single-tufted brushes with conventional toothbrushes [15, 16], and one study has investigated in orthodontic patients [17]. However, none of them has monitored their periodontal health in the longer term and have compared single-tufted toothbrushes with conventional and orthodontic toothbrushes together. To our knowledge, none of them investigated their effectiveness according to anterior or posterior region. It was hypothesized that single-tufted toothbrushes are more effective in plaque removal and the healing of gingival inflammation than conventional toothbrushes and as effective as orthodontic toothbrushes. Therefore, it was aimed to evaluate the effectiveness of different toothbrushes in removing plaque and gingival inflammation in individuals under fixed orthodontic treatment for gingivitis during three months.

Methods

Patient selection

This study was conducted at Istanbul Okan University, Faculty of Dentistry, between September 2023 and April 2024. The patients included in the study were selected from patients who were undergoing fixed orthodontic treatment and who came for regular dental visits in Istanbul Okan University, Faculty of Dentistry, Department of Orthodontics. A total of 59 systemically healthy patients (18–35 years old) who were undergoing orthodontic treatment with mandibular and maxillary fixed orthodontic brackets attached to the buccal surface were recruited. Figure 1 presents a flowchart of the patient selection process and sequence of the examinations. Informed consent was obtained from all individual participants included in the study. This study is in accordance with the ethical guidelines of the 1964 Helsinki Declaration and its later amendments. Ethical approval was obtained from the Istanbul University Faculty of Dentistry Ethics Committee (2023/30 Rev-1/ 681). In addition, it was registered with National Library of Medicine Clinical Trials Registry Platform (NCT06510179) and in accordance with the guidelines of the CONSORT (Consolidated Standards of Reporting Trials) Statement for clinical trials [18].

Fig. 1.

CONSORT 2010 flowchart diagram of the study

Inclusion and exclusion criteria

Inclusion criteria were orthodontic patients with at least 22 teeth with brackets, aged 18–35 years, systemically healthy, and non-smokers. Exclusion criteria included patients who were not leveling and aligning teeth in three dimensions (sagittal, horizontal, and vertical), those who were periodontally healthy or had periodontitis, smokers or had alcohol consumption, patients who had used antibiotics in the last three months, and pregnant patients.

Sample size calculation

In determining the number of participating in the study, the G*Power V. 3.1.9.6 program was used to determine the number of volunteers participating in the study. According to the power analysis result with 95% confidence (1-α), 80% test power (1-β), f = 1.703 effect size, it was determined that at least 10 samples should be taken for each group [19]. When the patient loss was evaluated as 10%, 14 individuals were included for each group, totaling 42 individuals.

Study design

This study was designed as a single-blind, randomized, controlled parallel group clinical trial. The results were reported following the Consolidated Standards of Reporting Trials (CONSORT) guidelines [18]. At the baseline, a periodontist (BAK) performed clinical examination on all the patients, and professional mechanical debridement was performed on all the patients in Istanbul Okan University, Department of Periodontics. Then, patients participating in the study were included in one of the three groups shown in Fig. 2 (conventional toothbrush1 (C-TB) group; orthodontic toothbrush2 (O-TB) group; single-tufted toothbrush3 (ST-TB) group) by an orthodontist (BM) who was blinded to the data collection using a computer-aided randomization program (www.randomizer.org). Three different kits (C-TB/ O-TB/ ST-TB and the same toothpaste) were delivered by the orthodontist each patient received in Istanbul Okan University, Department of Orthodontics. The orthodontist restricted the use of other oral cleaning tools (toothpaste, electric toothbrush, another toothbrush, or any mouth rinse) and delivered three different kits (C-TB/ O-TB/ ST-TB and the same toothpaste) each patient received. The orthodontist explained the importance of oral hygiene and provided the appropriate oral hygiene instructions for each group separately, detailed below for each group of patients across the mirror and also on the model. All the patients were recommended and instructed to use an interdental brush for interdental cleaning.

Fig. 2.

Three different design of toothbrushes. C-TB: conventional toothbrush; O-TB: orthodontic toothbrush; ST-TB: single-tufted toothbrush

Oral Hygiene Instruction of C-TB group:

Patients were instructed with the modified Bass technique [20]. In this technique, the toothbrush bristles were positioned 45° to the long axis of the tooth towards the base of the tooth at the gingival margin with a gentle back and forth rolling motion, then swept towards the occlusal surface of the teeth (Fig. 3a). To adapt to orthodontic braces, the same movement was repeated with the bristles positioned just occlusal to the brackets.

Fig. 3.

Appearance of three different toothbrushing techniques. (a) Modified Bass Technique. (b) Bass Technique. (c) Solo (Single-tooth circular) technique

Oral Hygiene Instruction of O-TB group:

The patients in this group were instructed to brush with the Bass technique [20]. In this technique, the toothbrush was placed on the gingival margin with its bristles at 45° to the long axis of the tooth. It was demonstrated by making back-and-forth movements and vibrating the brush at short intervals without lifting the bristles of the brush (Fig. 3b).

Oral Hygiene Instruction of ST-TB group:

In this group, patients were asked to brush their teeth only with ST-TB, and single-tooth circular brushing technique was explained, and dental plaque removal was demonstrated with circular movements around the brackets and following the gingival margin of each tooth (Fig. 3c).

Clinical examination and intervention

To determine the clinical periodontal status, Turesky modification of Quigley-Hein plaque index (TQHI) [21, 22] [after a disclosing solution4], probing pocket depth (PPD), gingival index (GI) [23, 24] and bleeding on probing [25] (BOP), were recorded at mesiobuccal, midbuccal, distobuccal, mesiolingual, midlingual, and distolingual sites of each tooth using a periodontal probe5. All measurements were performed by one examiner (BAK). The intraclass correlation coefficient (ICC) of the examiner was 0.99. Professional mechanical debridement was performed by an ultrasonic device and hand instruments on all the patients. Periodontal measurements were calculated on the average value of the mouth obtained from six surfaces of a tooth for each parameter. The measurements were then repeated at first, 6th weeks, and 3 months. After every recall, the orthodontist (BM) repeated the oral hygiene instructions to all three groups.

Statistical analysis

Data were analyzed with IBM SPSS V23. Compliance with normal distribution was evaluated by Shapiro-Wilk Test. One-way Analysis of Variance was used to compare the data conforming to normal distribution and Kruskal-Wallis Test was used to compare the data not conforming to normal distribution. Paired Two-Sample t Test was used to compare the data conforming to normal distribution before and after treatment in each group, and Wilcoxon Test was used to compare the data not conforming to normal distribution. Analysis results are presented as mean ± standard deviation (SD). Significance level was expressed as p < 0.050.

Results

Study population

Thirty-six patients completed the study (Fig. 1). No adverse effect was observed during the study. The baseline characteristics and orthodontic treatment duration of the patients were shown in Table 1. There were no significant differences in age (p = 0.699) and orthodontic treatment duration (p = 0.63) between the groups. Although there were only seven male patients in the study population, no significant difference was found in the group distribution (p = 0.165). No adverse effects of the treatments were reported by any individual.

Table 1.

Demographic data of the patients

		n	n%	Mean ± SD
SEX	Female	29	80.60%
	Male	7	19.40%
AGE		36		23.14 ± 3.86
			Month Mean ± SD
Duration of Orthodontic Treatment	C-TB	12	19.33 ± 4.52
	O-TB	12	17.58 ± 4.67
	ST-TB	12	19.08 ± 5.05

standard deviation [SD), conventional toothbrush group [C-TB], orthodontic toothbrush group [O-TB] and single-tufted toothbrush group [ST-TB]

Clinical parameters

The primary outcomes of this study were TQHI and gingival inflammation parameters. The analysis of TQHI, BOP, GI, and PPD scores at baseline, first week, sixth week, and third month for each group is presented in Table 2. No statistically significant differences were found between groups at baseline for any of the clinical parameters (p > 0.05). However, in all groups, there were statistically significant reductions in TQHI, BOP, GI, and PPD scores from baseline to each subsequent time point. In the first and sixth weeks, the O-TB and ST-TB groups exhibited significantly lower TQHI scores than the C-TB groups (Fig. 4). By the third month, the TQHI scores in the O-TB group had increased, becoming similar to those of the C-TB group (p < 0.05). However, The ST-TB group maintained significantly lower TQHI scores than the C-TB and O-TB groups in the third month (p < 0.001; Table 2). These findings were consistent with the GI scores. While no significant difference was observed between the C-TB and O-TB groups, the ST-TB group consistently displayed significantly lower GI scores than the other groups throughout the three months. Regarding BOP scores, the O-TB and ST-TB groups demonstrated significantly lower values compared to the C-TB group during the first and sixth weeks (Fig. 5). Only the ST-TB group maintained significantly lower BOP scores by the third month. In contrast, there were no statistically significant differences in PPD between groups at any time point (p = 0.424). Posterior regions had significantly higher plaque index, GI, and BOP levels at all time points than the anterior region. When comparing the groups based on the location of the teeth (posterior vs. anterior), no statistically significant differences were found between the groups (p = 0.074) (Table 3). The ST-TB group had significantly lower TQHI, GI and BOP scores regardless of tooth location.

Table 2.

Comparison of mean ± standard deviation (SD) for the parameters at time intervals in the groups

		C-TB Group	O-TB Group			ST-TB Group		p*
Parameters	Time	Mean ± SD	Mean ± SD			Mean ± SD		Group		Time			Group*Time
TQHI	Baseline	4.06 ± 0.19 a, A	3.67 ± 0.13 a, A			4.07 ± 0.15 a, A		< 0.001		< 0.001			< 0.001
	1st week	1.92 ± 0.19 a, C	1.08 ± 0.09 b, D			1.11 ± 0.13 b, B
	6th week	2.3 ± 0.22 a, B	1.44 ± 0.11 b, C			1.13 ± 0.06 b, B
	3rd month	2.55 ± 0.19 a, B	2.24 ± 0.16 a, B			1.41 ± 0.1 b, B
BOP	Baseline	88.48 ± 3.41 a, A	93.89 ± 1 a, A			90.52 ± 1.53 a, A		0.007		< 0.001			< 0.001
	1st week	45.3 ± 4.66 a, C	35.21 ± 2.83 ab, D			31.03 ± 1.59 b, C
	6th week	55.08 ± 3.62 a, B	44.41 ± 3.24 ab, C			36.56 ± 3 b, BC
	3rd month	62.26 ± 4.54 a, B	59.1 ± 3.18 a, B			44.04 ± 1.65 b, B
GI	Baseline	1.59 ± 0.04 a, A	1.66 ± 0.1 a, A			1.64 ± 0.08 a, A		0.047		< 0.001			0.203
	1st week	1.08 ± 0.06 ab, D	1.11 ± 0.06 a, D			0.96 ± 0.02 b, D
	6th week	1.18 ± 0.05 ab, C	1.19 ± 0.04 a, C			1 ± 0.02 b, C
	3rd month	1.23 ± 0.05 ab, B	1.28 ± 0.05 a, B			1.09 ± 0.02 b, B
PPD	Baseline	2.45 ± 0.06 a	2.47 ± 0.08 a			2.43 ± 0.07 a		0.896		0.004			0.424
	1st week	2.38 ± 0.06 b	2.42 ± 0.08 b			2.4 ± 0.07 b
	6th week	2.4 ± 0.06 abc	2.46 ± 0.09 abc			2.39 ± 0.07 abc
	3rd month	2.41 ± 0.06 c	2.44 ± 0.08 c			2.4 ± 0.07 c

Turesky modified Quigley Hein plaque index [TQHI], bleeding on probing [BOP], gingival index [GI] and probing pocket depth [PPD], the conventional toothbrush group [C-TB], orthodontic toothbrush group [O-TB] and single-tufted toothbrush group [ST-TB]

A, B, C: Different letters in the same column indicate statistically significant difference (p < 0.05)

a, b: Different letters in the same row indicate statistically significant difference (p < 0.05)

* Two-way mixed design ANOVA

Fig. 4.

Mean Turesky modification of Quigley-Hein plaque Index (TQHI) values at the baseline, after first and sixth weeks and third month for conventional toothbrush, orthodontic toothbrush and single-tufted toothbrush. ^*Two-way mixed design ANOVA (p < 0.05)

Fig. 5.

Mean bleeding on probing (BOP) values at the baseline, after first and sixth weeks and third month for conventional toothbrush, orthodontic toothbrush and single-tufted toothbrush. ^*Two-way mixed design ANOVA (p < 0.05)

Table 3.

Comparison of mean ± SD for anterior/posterior regions across groups for parameters at different time intervals

			C-TB Group	O-TB Group	ST-TB Group			p*
Parameters		Time	Mean ± SD	Mean ± SD	Mean ± SD			Group	Location (L)		Time (T)				G*T	G*L	L*T	G*L*T
TQHI		Baseline (Anterior)	3.89 ± 0.21 x, a, A	3.59 ± 0.16 x, b, A	3.79 ± 0.16 x, c, A			< 0.001	0.018		< 0.001				< 0.001	0.738	0.007	0.081
		Baseline (Posterior)	4.14 ± 0.18 x, a, A	3.74 ± 0.16 x, b, A	4.29 ± 0.18 x, c, A
		1st week (Anterior)	1.8 ± 0.31 y, a, B	0.92 ± 0.11 y, b, B	1 ± 0.11 y, b, B
		1st week (Posterior)	2.3 ± 0.32 x, a, B	1.21 ± 0.11 x, b, B	1.25 ± 0.15 x, b, B
		6th week (Anterior)	2.12 ± 0.21 y, a, B	1.13 ± 0.11 y, b, B	0.95 ± 0.06 y, b, B
		6th week (Posterior)	2.52 ± 0.24 x, a, B	1.71 ± 0.16 x, b, B	1.28 ± 0.08 x, b, B
		3rd month (Anterior)	2.21 ± 0.21 y, a, B	1.62 ± 0.09 y, a, C	1.17 ± 0.1 y, b, B
		3rd month (Posterior)	2.83 ± 0.21 x, a, B	2.73 ± 0.29 x, a, C	1.67 ± 0.13 x, b, B
BOP		Baseline (Anterior)	83.33 ± 3.85 x, a, A	91.92 ± 1.25 x, a, A	88.17 ± 1.71 x, a, A			0.006	< 0.001		< 0.001				< 0.001	0.511	< 0.001	0.741
		Baseline (Posterior)	85.36 ± 3.38 x, a, A	95.13 ± 1.48 x, a, A	92.15 ± 2.27 x, a, A
		1st week (Anterior)	40.39 ± 5.35 y, a, D	30.6 ± 2.58 y, ab, D	26.98 ± 2.32 y, b, C
		1st week (Posterior)	49.19 ± 5.11 x, a, D	39.97 ± 3.91 x, ab, D	34.24 ± 1.91 x, b, C
		6th week (Anterior)	50.69 ± 4.26 y, a, C	39.37 ± 1.9 y, b, C	28.15 ± 2.5 y, b, C
		6th week (Posterior)	58.61 ± 4.43 x, a, C	50.27 ± 5.09 x, b, C	43.2 ± 3.97 x, b, C
		3rd month (Anterior)	56.25 ± 4.5 y, a, B	51.55 ± 4.09 y, a, B	39.23 ± 2.34 y, b, B
		3rd month (Posterior)	67.02 ± 5.47 x, a, B	65.05 ± 3.79 x, a, B	52.64 ± 2.68 x, b, B
GI		Baseline (Anterior)	1.57 ± 0.06 y, a, A	1.58 ± 0.11 y, a, A	1.57 ± 0.05 y, a, A			0,012	< 0.001		< 0.001				0.721	0.21	0.066	0.163
		Baseline (Posterior)	1.61 ± 0.05 x, a, A	1.73 ± 0.13 x, a, A	1.7 ± 0.1 x, a, A
		1st week (Anterior)	1.06 ± 0.05 y, a, D	1.09 ± 0.08 y, a, D	0.94 ± 0.02 y, b, D
		1st week (Posterior)	1.1 ± 0.07 x, a, D	1.14 ± 0.06 x, a, D	0.97 ± 0.02 x, b, D
		6th week (Anterior)	1.12 ± 0.05 y, a, C	1.14 ± 0.07 y, a, C	0.9 ± 0.01 y, b, C
		6th week (Posterior)	1.22 ± 0.06 x, a, C	1.23 ± 0.04 x, a, C	1.08 ± 0.04 x, b, C
		3rd month (Anterior)	1.13 ± 0.05 y, a, B	1.2 ± 0.07 y, a, B	0.97 ± 0.02 y, b, B
		3rd month (Posterior)	1.3 ± 0.06 x, a, B	1.34 ± 0.04 x, a, B	1.2 ± 0.04 x, b, B

Turesky modified Quigley Hein plaque index [TQHI], bleeding on probing [BOP], gingival index [GI] and pocket depth [PD], the conventional toothbrush group [C-TB], orthodontic toothbrush group [O-TB] and single-tufted toothbrush group [ST-TB]

A, B, C: Different letters in the same column indicate statistically significant difference (p <  0.05)

a, b: Different letters in the same row indicate statistically significant difference (p < 0.05)

x, y: Different letters in the same column indicate statistically significant difference (p < 0.05)

* Two-way mixed design ANOVA

Discussion

This study was performed as a single-blind randomized controlled trial to compare the effectiveness of different types of toothbrushes in reducing dental plaque and gingival inflammation in orthodontic patients with gingivitis during three months. Although all the groups had statistically significant reductions in clinical parameters according to baseline, the ST-TB group showed a significantly higher effect on plaque index, GI and BOP levels during three months compared to C-TB. In addition, the ST-TB group was significantly the most effective toothbrush on BOP, GI and TQHI in the third month.

The majority of studies evaluating the short-time effectiveness of brushes and brushing techniques have evaluated the efficacy of brushes in removing plaque, and most have examined periodontally healthy orthodontic patients. Aeran et al. compared the effectiveness of ST-TB and C-TB on dental biofilm and gingival inflammation for a short time (72 h) in generalized gingivitis orthodontic patients and found that ST-TB was more effective for controlling dental plaque than conventional toothbrushes parallel to our results [16]. Other studies comparing ST-TB and C-TB for the short-time effect also found that ST-TB was more effective in biofilm removal [15, 17]. However, unlike the present study, the orthodontic patients in these studies were periodontally healthy. The studies investigated the effectiveness between O-TB and C-TB were found O-TB was significantly more effective in plaque removal [11, 26, 27]. A meta-analysis comparing O-TB with C-TB reported that there was scientific evidence for recommending the use of an O-TB instead of a C-TB based on the analysis of plaque index control while not gingival bleeding was modified by an orthodontic design toothbrush. Only two of the included studies were evaluated gingival inflammation in this meta-analysis, and none of them included gingivitis patients [28].

Besides the differences in toothbrushes, the brushing techniques were also different due to the toothbrush type in the current study. In the studies comparing different tooth brushing techniques in fixed orthodontic patients, modified Bass and Bass techniques were reported to be more effective in reducing periodontal clinical parameters of plaque index and gingival index in patients with fixed orthodontic appliances [26, 29, 30]. In parallel to these studies, modified Bass techniques were instructed in the C-TB group, and Bass technique was instructed in the O-TB group in the present study. In the ST-TB group, Solo technique was instructed. Plaque-retentive areas such as the niches around the brackets, interdental areas, and oral-distal tooth surfaces might not be reached by flat-trimmed toothbrushes. They might not remove dental plaque with non-traumatic slight pressure. Since a ST-TB was used on each tooth surface, rotation movement with vibration made brushing more carefully. ST-TBs have small heads and bristles directed to the area to be brushed. This might explain why ST-TB was more effective in dental plaque removal and gingival inflammation in the current study. Nevertheless, other studies investigating the effectiveness of ST-TB have not specifically described the usage technique for this toothbrush [15–17], it was thought the techniques were similar to the present study. Cunha et al. in their study investigating short-time (72 h) effectiveness of toothbrushes was found that combination with C-TB and ST-TB was more effective for controlling dental biofilm formation in orthodontic patients [17]. They compared different brushes in the same patients by using them at certain intervals. However, the differences in the baseline plaque index values of each brush group may have made it difficult to compare the reduction in plaque level. The findings of the present study were consistent with methodologically comparable studies that reported a reduction in dental biofilm accumulation in non-orthodontic patients using single-tufted toothbrushes [13, 15]. As expected in the present study, all the groups had reduction in gingival inflammation levels after professional dental cleaning and oral hygiene procedures.

In the present study, gingival inflammation levels were reduced in all groups after professional dental cleaning and oral hygiene applications. Besides, a statistically significant decrease in BOP and GI values was observed in the ST-TB group. Inflammation continued in the groups, albeit less severely, due to the continuation of inflammation due to predisposing factors during the orthodontic treatment. However, the significant decrease in GI and BOP, which are early signs of inflammation, in patients brushing with ST-TB for three months, parallel to the TQHI values, suggests that this toothbrush type and technique used are advantageous in plaque removal in orthodontic patients. Most of the studies evaluated the effectiveness of ST-TB compared to baseline and after 72 h [16, 17]. Cunha et al. found that the combined usage of C-TB and ST-TB significantly improved gingival bleeding index scores in 72 h [17]. Nevertheless, their study did not mention Periodontal diagnosis and standardization of included patients. However, in contrast to the present study, Aeran et al. [16] and Cunha et al. [17] evaluated the effectiveness of different toothbrushes in the same patient groups for 72 h with a 3-day washout pre-experimental period.

Teeth were also evaluated by their localization (anterior or posterior) to assess whether tooth location influenced brushing effectiveness. In all the groups, the parameters of posterior teeth were higher than those of anterior teeth. Because posterior teeth have multi-rooted teeth and difficulties in toothbrush access, this outcome is expected. When groups are compared, the ST-TB group was again more effective on TQHI, GI, and BOP levels regardless of the location of teeth. However, in the intragroup evaluation of ST-TB, the effectiveness was lower in posterior teeth than anterior teeth, as parallel all groups.

Although the effectiveness of different toothbrushes was analyzed due to teeth location, the surfaces were not compared with brackets and oral surfaces or the difference according to jaws. They might be thought to be limitations for the present study. Another limitation for the present study might be sample size. Since eliminating potential risk factors and indicators with exclusion criteria, the sample size became relatively small although it was bigger than the sample number of the results of power analysis. Other potential limitations of this study are that the diet habits and lifestyles of the young adult patients, except for smoking or alcohol consumption, are not included in the evaluation, and the toothbrushing was conducted in a home setting without direct supervision by the examiners. This raises the possibility that the patients may not have been fully compliant with the instructions, which could have influenced the observed results. Future studies can be planned which using periodic computer-based intraoral image analysis of dental plaque to determine oral hygiene performance.

Conclusion

Within the limits of this study, single-tufted toothbrushes were significantly more effective in reducing gingival and plaque indices in patients with fixed orthodontic appliances and in maintaining periodontal health in these patients for a period of three months. Further studies need to confirm these findings and show the effectiveness of this method on periodontal tissue health in patients with fixed orthodontic appliances.

Electronic supplementary material

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Abbreviations

TQHI

Turesky modification of Quigley-Hein plaque index

GI

Gingival index

BOP

Bleeding on probing

PPD

Probing Pocket depth

C

TB-Conventional toothbrush

O

TB-Orthodontic toothbrush

ST

TB-Single-tufted toothbrush

CONSORT

Consolidated Standards of Reporting Trials

ICC

Intraclass correlation coefficient

SD

Standard deviation

Author contributions

GAS wrote the main manuscript text and BAK prepared Figs. 1, 2, 3, 4 and 5. All authors reviewed the manuscript.

Funding

No funding was received.

Data availability

The data that support 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 ethical guidelines of the 1964 Helsinki Declaration and its later amendments. Ethical approval was obtained from the Istanbul University Faculty of Dentistry Ethics Committee (2023/30 Rev-1/ 681). Informed consent was obtained from each patient included in the study.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.