Is there any differential efficacy among different vibrational frequencies and duration of sessions on tooth movement acceleration? A systematic review

Wesam Mhd Mounir Bakdach; Rania Hadad

doi:10.4103/jioh.jioh_91_20

REVIEW ARTICLE

Year : 2020 | Volume : 12 | Issue : 4 | Page : 289-298

Is there any differential efficacy among different vibrational frequencies and duration of sessions on tooth movement acceleration? A systematic review

Wesam Mhd Mounir Bakdach, Rania Hadad
Department of Orthodontics, Faculty of Dentistry, University of Damascus, Damascus, Syria

Date of Submission	11-Mar-2020
Date of Decision	04-May-2020
Date of Acceptance	09-May-2020
Date of Web Publication	20-Aug-2020

Correspondence Address:
Dr. Wesam Mhd Mounir Bakdach
Department of Orthodontics, Faculty of Dentistry, University of Damascus, Damascus.
Syria

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/jioh.jioh_91_20

Abstract

Aim: The aim of this review was to appraise the existence of any differential efficacy among different vibrational frequencies and duration of sessions on the acceleration of tooth movement. Materials and Methods: An extensive search was performed from inception to November 2019 in seven databases. Only randomized controlled trials were included. Risk of bias was assessed using Cochrane’s collaboration tool. Six different combinations of frequencies and durations were utilized by the studies including: (30 Hz: 20 min/day), (111 Hz: 20 min/day), (113 Hz: 10 min/day), (120 Hz: 5 min/day), (125 Hz: 20 min/day) and (125 Hz: 15 min/day). Results: Significant differences were found in (113 Hz: 10 min/day), (120 Hz: 5 min/day), and (125 Hz: 15 min/day) compared with control groups. Mainly, no significant differences were appreciated among other combinations. Finally, attrition bias was accounted for the principal factor affecting the methodology of current studies. Conclusion: According to the available information, a weak evidence suggests a differential efficacy on tooth movement acceleration among different vibrational frequencies and durations. Parameters of 113 Hz applied for 10 min/day, 120 Hz applied for 5 min/day and 125 Hz applied for 15 min/day seemed to be more effective than the other utilized parameter

Keywords: Acceleration, Orthodontics, Tooth Movement, Vibration, Vibrational Force

How to cite this article:
Bakdach WM, Hadad R. Is there any differential efficacy among different vibrational frequencies and duration of sessions on tooth movement acceleration? A systematic review. J Int Oral Health 2020;12:289-98

How to cite this URL:
Bakdach WM, Hadad R. Is there any differential efficacy among different vibrational frequencies and duration of sessions on tooth movement acceleration? A systematic review. J Int Oral Health [serial online] 2020 [cited 2023 Dec 9];12:289-98. Available from: https://www.jioh.org/text.asp?2020/12/4/289/292765

Introduction

Over the last decade, many research projects were conducted to investigate the efficacy of various interventions on speeding up tooth movement.^[1] Among these interventions, supplemental vibrational force application has been recently introduced.^[2] Initially, histological and microcomputed tomography-based investigations, mainly on long bones and craniofacial tissues, showed that vibrational force application increased bone re-modeling, markedly improved bone quality,^[3] and effectively modulated sutures’ growth by enhancing osteogenesis.^[4] Consistent with these findings, Nishimura et al.^[2] proposed a hypothesis suggesting that vibrational force application could speed up tooth movement because periodontal ligaments resemble sutures’ components. Ever since, exponential growth in the number of studies and patented devices regarding this field has become apparent.

The electronic literature searches on PubMed and Scopus have yielded three systematic reviews^[5],[6],[7] assessing the impact of supplemental vibrational force on tooth movement acceleration. The three reviews included almost the same studies that were mainly assessing the efficacy of AcceleDent device (30 Hz: 20 min/day), but unexpectedly generalized their AcceleDent-based findings on all vibrational devices despite the differences in vibrational frequencies and duration of sessions. In confirmation with this criticism, Judex and Pongkitwitoon^[8] revealed a differential efficacy among different vibrational devices to alter the cellular response of osteoblasts, fibroblasts, and osteoclasts.

This systematic review summarizing the currently used vibrational parameters, appraising their potential differential efficacy on tooth movement acceleration, and suggesting the best available parameters based on the current evidence was the appropriate next step.

Materials and Methods

Searching strategy

An extensive electronic search was performed independently by the two reviewers with no restrictions on language, year, or publication status from inception to November 2019 in the following databases: The Cochrane Central Register of controlled Trials, Scopus, TRIP, PubMed, OpenGrey (for grey literature), and proQuest (for dissertations and theses). Bibliographies of the included studies and relevant reviews were screened for further possible studies. In progress, trials were also checked through World Health Organization International Clinical Trials Registry Platform (ICTRP). Further details on the searching strategy and the keywords used could be found in [Supplementary Table 1].

Supplementary Table 1: Electronic Searching Strategy

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Question

The following participants, intervention, comparison, outcomes and study design (PICOS) format was used to consider studies eligible for this systematic review:

Participants (P): Healthy male and female patients (at least 10 patients in each study) of any ethnic group and at any age who underwent an orthodontic treatment.

Interventions (I): Orthodontic treatment assisted by vibration application to accelerate tooth movement.

Comparisons (C): Orthodontic treatment without vibrational stimulation.

Outcomes (O): The rate of tooth movement expressed by millimeters of movement per time or any measurement that can give an idea about the effectiveness of the intervention applied.

Study design (S): Only randomized controlled trials (RCTs) were eligible for inclusion.

Study selection and data extraction

Study selection and data extraction were performed independently by the two reviewers. Initially, a screening process was carried out by assessing titles and abstracts of the studies identified by the searches. Then, full-text copies of the potentially relevant articles were assessed in depth. Disagreements on the eligibility between both reviewers were robustly resolved by discussion. Finally, information was extracted from studies including authors’ names, setting, PICOS, follow-up period, and main findings. When any doubtful information was encountered, corresponding authors were contacted for clarifications.

Assessing the risk of bias of included studies

The Cochrane collaboration’s tool for assessing the risk of bias was used to assess the risk of bias of the studies included. Seven domains were described as at high, low, or unclear risk of bias including:

Random sequence generation (selection bias),

Allocation concealment (selection bias),

Blinding of participants and personnel (performance bias),

Blinding of outcome assessors (detection bias),

Incomplete outcome data (attrition bias),

Selective outcome reporting (reporting bias),

Other sources of bias. Then, overall risk of bias for each included trial was stated according to the following:
A low risk of bias was stated when all fields were assessed to be at low risk of bias.

A moderate risk of bias was stated when one or more fields were assessed to be at unclear risk of bias.

A high risk of bias was stated when one or more fields were assessed to be at high risk of bias.

This assessment was performed by the two reviewers independently, then, judgments were compared and any disagreement was resolved through discussion and consensus.

Data synthesis

Conducting meta-analysis was not attainable due to the heterogeneity on different aspects among the eligible studies including type of tooth movement achieved (i.e., alignment or retraction), aligning scenario (i.e., extraction or nonextraction treatments), and different data distribution across studies (i.e., normal and abnormal distributions).

Results

Literature flow

A total number of 341 references were identified through the electronic search. Duplicates, reviews, and irrelevant references were eliminated by checking titles and/or abstracts. As a result, 33 references were potentially relevant and hence, checked in depth. Final results included 17 completed RCTs and 5 ongoing RCTs. [Figure 1] shows the PRISMA flow chart including the detailed searching process. Excluded studies with reasons beyond exclusion are provided in [Supplementary Table 2].

Figure 1: PRISMA flow chart

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Supplementary Table 2: Excluded studies and reasons for exclusion

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Description of studies

Seventeen completed RCTs were conducted, to date, to investigate the effect of supplemental vibrational force on tooth movement acceleration. Five of the included completed studies were theses. Different types of tooth movements were established including leveling and alignment, canine retraction, and en masse retraction. The different commercial devices that were used to deliver vibrations are AcceleDent, VPro5, electrical toothbrush, and tooth masseuse. [Table 1] and [Table 2] summarize the characteristics of included completed and ongoing studies, respectively.

Table 1: Characteristics of the included completed studies assessing the effect of vibration on tooth movement acceleration

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Table 2: Characteristics of ongoing studies facilitated by vibration: country, study design, and intervention

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Effect of interventions

The effect of applying a vibrational frequency of 30 Hz for 20 min/day on tooth movement acceleration

The commercial device that is designed to deliver these parameters is the AcceleDent device (OrthoAccel Technologies, Bellaire, Texas, USA). Twelve RCTs were conducted to assess its efficacy on tooth movement acceleration. Different types of tooth movements were established in these studies including:

Mandible leveling and alignment using fixed appliances

Four RCTs, comprising 215 patients, assessed mandibular leveling and alignment alterations when fixed appliances were enhanced by supplemental vibrational force delivered from AcceleDent: Bulic,^[9] Miles and Fisher,^[10] Woodhouse et al.,^[11] and Chouinard.^[12] All four studies revealed insignificant differences in Little’s Irregularity Index measurement between experimental and control groups. Pooling data were unattainable due to different treatment scenarios (i.e., extraction or nonextraction treatments) and different data distribution across studies (i.e., normal and abnormal distributions).

Maxillary and mandible leveling and alignment using aligners

Four studies, comprising 145 patients, assessed maxillary and mandibular leveling and alignment alterations when aligners were enhanced by supplemental vibrational force derived from AcceleDent: Bragassa,^[13] Lombardo et al.,^[14] Katchooi et al.,^[15] and Pescheret.^[16] Three of which found a nonsignificant difference between experimental and control groups,^{[13],[15],[16]} whereas Lombardo et al.^[14] found a better accuracy in terms of upper incisor rotation when aligners were changed every 14 days and enhanced by vibration compared with nonvibrational application or vibration enhancing changing aligners every 7 days. Pooling data were unattainable due to the differences in the frequency of changing aligners among the studies.

Upper canine retraction

Two studies, comprising 67 patients, assessed alterations in upper canine retraction when treatment was enhanced by supplemental vibrational force derived from AcceleDent: Taha et al.^[17] and Pavlin et al.^[18]

Pavlin et al.^[18] revealed the effectiveness of AcceleDent in accelerating canine retraction, whereas Taha et al.^[17] found no differences between experimental and control groups.

Although both studies were parallel designed and were assessing the same outcome, pooling data were not applicable due to the heterogeneity in the way of presenting the amount of canine movement. Pavlin et al.^[18] calculated the total average monthly rate of canine retraction for each group without specifying the amount of movement at each time point, unlike Taha et al.^[17] who mentioned the amount of retraction in each month (time-point). Moreover, calculating the combined amount of retraction to homogenize data was also unattainable as patients were dropping out during the treatment period in the study of Taha et al.

En masse retraction

Two studies, comprising 121 patients, assessed the effect of AcceleDent in accelerating en masse retraction: DiBiase et al.^[19] and Miles et al.^[20] DiBiase et al. randomly allocated patients to either vibration, sham, or control groups and assessed the rate of mandibular arch space closure. On the contrary, Miles et al.^[20] allocated patients to either vibration or control groups and assessed the rate of maxillary arch space closure. In both studies, the amount of space closure was regularly measured from a series of dental models and their results showed a nonsignificant difference in tooth movement acceleration between experimental and control groups.

2. The effect of applying a vibrational frequency of 111 Hz for 20 min/day on tooth movement acceleration

One RCT, Miles et al.,^[21] was conducted to assess the efficacy of vibrational frequency of 111 Hz applied for 20 min per day on tooth movement acceleration. The commercial device that is designed to deliver these parameters is the Tooth masseuse device (Good Vibrations, Raintree Essix, Inc., New Orleans, USA). Miles et al.^[21] allocated 66 patients with mild lower crowding to either vibration or control groups. The rate of tooth movement was assessed using Little’s Irregularity Index measured on sequential dental casts. Results showed nonsignificant differences between both groups.

3. The effect of applying a vibrational frequency of 113 Hz for 10 min/day on tooth movement acceleration

One RCT assessed this outcome, Liao et al.,^[22] using electrical toothbrushes (Hamming Bird, Oral B, Braun, P&G company, Cincinnati, Ohio, USA) and comprising thirteen patients. Upper right and left canines of each patient were randomly allocated to either vibration or control group. The amount of canine retraction was used to assess tooth movement acceleration. Results showed that vibration enhancing tooth movement is considered to be clinically beneficial.

4. The effect of applying a vibrational frequency of 120 Hz for 5 min/day on tooth movement acceleration

One RCT, Alansari et al.,^[23] was conducted to assess the efficacy of these parameters on enhancing maxillary and mandibular leveling and alignment using aligners. The commercial device that is designed to deliver these parameters is the VPro5 device (VPro5, Propel Orthodontics, Ossining, New York). Sixty patients were randomly allocated into the following groups: 14-day control (changing aligner every 14 days), 7-day sham, 7-day vibration, 5-day sham, and 5-day vibration. Results showed that time intervals between aligners significantly reduced by daily vibration treatment.

5. The effect of applying the vibrational frequency of 125 Hz for 15 min/day on tooth movement acceleration

One RCT assessed this outcome, Leethanakul et al.,^[24] using electrical toothbrushes (Colgate Motion-Multi Action, Colgate-Palmolive Company, New York, USA)and comprising 15 patients. A randomized split-mouth design was applied to allocate upper canines to either vibration or control group. A series of plaster models were used to assess tooth movement acceleration by measuring the amount of canine retraction each month. Results showed that vibratory stimuli using an electric toothbrush accelerated tooth movement.

6. The effect of applying the vibrational frequency of 125 Hz for 20 min/day on tooth movement acceleration

One RCT assessed this outcome, Azeem et al.,^[25] using electrical toothbrushes (Oral-B Triumph, OD17; P&G company, Cincinnati, Ohio, USA) and comprising 28 patients. Upper right and left canines of each patient were randomly allocated to either vibration or control group. Tooth movement acceleration was assessed by measuring the amount of canine retraction each month from a series of dental casts. Results showed that vibrations generated from electric toothbrushes did not accelerate tooth movement.

Risk of bias in included studies

Five studies were at low risk of bias,^{[10],[13],[15],[20],[24]} 11 studies were at moderate risk of bias,^{[9],[11],[12],[14],[16],[17],[18],[21],[22],[23],[25]} and 1 study was at high risk of bias.^[19] The most principal factors affecting the methodology of current studies were the incomplete outcome data (5.88% at high risk and 35.29% at unclear risk of attrition bias) and undefined allocation concealment (58.82% did not mention the allocation concealment). [Figure 2] and [Figure 3] show the summary and graph of risk of bias for the included studies. More details regarding the risk of bias assessment with reasons supporting each assessment could be found in [Supplementary Table 3].

Figure 2: Risk of bias summary: review authors’ judgements about each risk of bias item for included studies

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Figure 3: Risk of bias graph: review authors’ judgements about each risk of bias item presented as percentages across all included studies

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Supplementary Table 3: Assessment of risk of bias with supporting reasons for each assessment

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Discussion

Vibrational devices have been recently introduced to enhance orthodontic treatments. Being portable, hand-sized, easily applied, and home-used at convenient times allowed them to become an attention-grabbing research topic. Seventeen RCTs^{[9],[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22],[23],[24],[25]} were conducted to evaluate the efficacy of different vibrational devices in accelerating tooth movement. To the best of our knowledge, this is the first systematic review aimed to investigate the existence of any differential efficacy among different vibrational parameters on tooth movement acceleration. Overall, six vibrational combinations were used: (30 Hz for 20 min/day using AcceleDent device), (111 Hz for 20 min/ day using Tooth Masseuse device), (113 Hz for 10 min/day using electrical toothbrushes), (120 Hz for 5 min/day using VPro5 device), (125 Hz for 20 min/day using electrical toothbrushes), and (125 Hz for 15 min/day using electrical toothbrushes). According to the available information, vibrational parameters of 113 Hz for 10 min/day, 120 Hz for 5 min/day, and 125 Hz, 15 min/day are more effective than other used parameters in accelerating tooth movement.

The impact vibrational frequency on tooth movement acceleration

Several in vitro and in vivo investigations aimed to compare the effect of various frequencies on cell proliferation and bone formation stimulation.^{[26],[27],[28]} According to cell culture studies, exposing mesenchymal progenitor cells to vibrations at 100 Hz revealed a significant increase in cell proliferation compared with 30 Hz.^[26] Similarly, Judex et al.^[27] found that 100 Hz was more effective than 30 Hz in increasing the numbers of macrophages. Regarding in vivo studies, Judex et al.^[28] deduced that applying vibrations at 90 Hz raised the level of bone formation, in ovariectomized rats, to a much greater extent than 45 Hz application.

The included RCTs used frequencies of 125, 120, 113, 111, and 30 Hz. Five studies applied vibration with a frequency >100 Hz.^{[21],[22],[23],[24],[25]} Three of which showed a significantly increased tooth movement in the vibration group compared with the control.^{[22],[23],[24]} On the contrary, 10 of 12 RCTs using a frequency of 30 Hz revealed ineffectiveness in accelerating tooth movement. Thus, it seems that the clinical investigations support the previously mentioned in vitro and in vivo investigations suggesting that higher frequencies are more effective than lower ones.

The impact of duration of sessions on tooth movement acceleration

The impact of increasing the duration of sessions (min/day) has also been controversial. Results of in vitro and in vivo studies suggest that increasing loading duration increases the cellular response until a point of saturation, where no longer increase is observed.^{[8],[29],[30],[31]} According to Judex et al.,^[27] increasing the duration of session from 15 to 30 min/day led to a significantly greater cellular response; however, extending the duration further to 60 min/day provided a similar output to that observed in 30 min/day.

Fourteen of the studies included applied vibrations for 20 min/day,^{[9],[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[25]} whereas one study applied it for 15 min/day.^[24] Another study used a duration of 10 min/day^[22] and the last study decreased the duration to 5 min/day.^[23] Studies with 15, 10, and 5 min application showed a beneficial clinical effect on tooth movement; however, different conclusions were drawn from studies using 20 min application.

Comparing clinical investigations with experimental ones suggests a limit of increasing duration of the session, after which no differences could be observed or perhaps might, clinically, lead to an adverse effect. The long duration of sessions could conceivably cause hyaline degeneration due to the increased stress levels in the periodontal ligament resulting in tooth movement deceleration. Further investigations are still needed to determine the adequate duration of sessions that could provide the maximum cellular output and indeed the minimal impact on patient’s compliance as well.

Limitations

Meta-analysis was not conducted due to the existed heterogeneity among the included studies. The limited number of studies assessing each addressed parameter is also considered as a limitation of this review and reflecting the need for more precise trials on this topic.

Recommendation

As discussed in this review, a weak evidence shows that higher vibrational frequencies are more effective than lower ones. Similarly, a weak evidence suggests that increasing the duration of the session is useful until a point of saturation, after which no differences could be observed or perhaps might lead to an adverse effect.

Conclusion

According to the available information, a weak evidence suggests a differential efficacy on tooth movement acceleration among different vibrational frequencies and duration of sessions. Vibrational parameters of 113 Hz for 10 min/day, 120 Hz for 5 min/day, and 125 Hz for 15 min/day seemed to be more effective than other used parameters in accelerating tooth movement.

Acknowledgement

Nil.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Authors contributions

WMMB and RH performed the electronic search, data extraction and risk of bias assessment independently. WMMB and RH performed the interpretation of the studies’ results through a robust discussion. WMMB drafted the manuscript. RH read, corrected and then approved the final manuscript.

Ethical policy and Institutional Review board statement

Not applicable.

Declaration of patient consent

Not applicable.

Data availability statement

Not applicable.

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