Randomized controlled trial
Effectiveness of pulsed electromagnetic field for pain caused by placement of initial orthodontic wire in female orthodontic patients: A preliminary single-blind randomized clinical trial

https://doi.org/10.1016/j.ajodo.2017.04.022Get rights and content

Highlights

  • Pulsed electromagnetic field was used to relieve pain of orthodontic tooth movement.

  • Average pain scores were greater in clenching state compared with resting state.

  • PEMF relieved pain 24, 48, and 72 hours after placement of the initial archwires.

  • PEMF may be effective in reducing pain caused by initial orthodontic tooth movement.

Introduction

The purpose of this 2-arm parallel trial was to assess the effects of pulsed electromagnetic field (PEMF) on the reduction of pain caused by initial orthodontic tooth movement.

Methods

Thirty-three female patients (mean age, 16.8 ± 3.8 years) who began orthodontic treatment using fixed appliances were examined. In the pilot study, male patients were less likely to use the PEMF device (epatchQ; Speed Dental, Seoul, Korea) and answer a survey consistently, so eligibility criteria were female patients who were periodontally and systemically healthy at the initiation of treatment and had no history of dental pain in the prior 2 weeks or who used no medications (anti-inflammatory or analgesic drugs) during the experiment period. Each patient had brackets bonded on the maxillary teeth, and a 0.014-in nickel-titanium archwire was tied with elastomeric rings. Their maxillary arches were randomly divided into left and right sides in a split-mouth design: a normal PEMF device (experimental group) was used on 1 side, and a PEMF device with an inversely inserted battery (placebo group) was used on the opposite side of the arch for 7 hours on 3 consecutive nights. A Google survey link was sent to the patients’ mobile phones via text message, and they were instructed to record their current pain on the survey. The survey was sent a total of 6 times after insertion of the initial archwire at 0 (T0), 2 (T1), 6 (T2), 24 (T3), 48 (T4), and 72 (T5) hours. Patients recorded the degree of pain in resting and clenching states using a numeric rating scale (NRS) from 1 (no pain) to 10 (worst pain). PEMF devices were used after T2. Generalized linear mixed models, along with ancillary pairwise analyses, were used to model and evaluate the differences in pain reported over 72 hours.

Results

The NRS scores did not differ across the groups during the before-PEMF phase for resting (mean difference, −0.07; 95% confidence interval [CI], −0.73 to 0.59; P = 0.842) and clenching (mean difference, −0.28; 95% CI, −1.11 to 0.56, P = 0.513). During the after-PEMF phase, NRS scores in the experimental group were significantly lower than those in the placebo group during both resting (mean difference, −1.46; 95% CI, −2.06 to −0.85; P = <0.001) and clenching (mean difference, −1.88; 95% CI, −2.74 to −1.02, P = <0.001). The NRS scores did not differ across the groups during the before-PEMF phase for either state but were significantly lower in the experimental group than in the placebo group at T3, T4, and T5 (P <0.01). The average NRS score in the clenching state was significantly greater than in the resting state.

Conclusions

PEMF was effective in reducing orthodontic pain caused by initial archwire placement.

Registration

The trial was not registered.

Protocol

The protocol was not published before trial commencement.

Section snippets

Specific objectives and hypotheses

The aim of this study was to evaluate the efficiency of PEMF in reducing orthodontic pain after insertion of the initial archwire. The null hypothesis was that there would be no difference in the management of orthodontic pain between the experimental and placebo samples.

Trial design and any changes after trial commencement

This was a single-blind, split-mouth, 2-arm parallel randomized clinical trial with a 1:1 allocation ratio. No changes occurred after trial commencement.

Participants, eligibility criteria, and settings

This randomized controlled trial was conducted at the Department of Orthodontics of Wonkwang University Daejeon Hospital in Korea from September 2015 to March 2016. In the pilot study, male patients were less likely to use the PEMF device (epatchQ; Speed Dental, Seoul, Korea) and answer a survey consistently, so this study was confined to

Participant flow

The study took place over 7 months from September 2015 to March 2016. Initially, 33 patients were recruited, but 3 did not comply. Two of the 3 did not complete the questionnaire, and 1 failed to use the PEMF device because of skin pruritus. These 3 patients were excluded from the study (Fig 5).

Baseline data

As shown previously, the baseline characteristics of the patients in each group were similar, with no significant differences between groups concerning age, sex, and health (dental and general).

Numbers analyzed for each outcome, estimation and precision, subgroup analysis

Table I,

Main findings

Pain is inevitable during orthodontic treatment. Because of this, some people hesitate about or avoid orthodontic treatment. Despite the esthetic and functional demands patients may want or need, they tend to postpone orthodontic treatment and even rationalize this delay.23, 24

The intersex difference in pain perception has been studied for a long time, and it is still controversial.25, 26 The role of age in pain also remains poorly understood. Bergius et al27 reported higher levels of pain in

Conclusions

PEMF devices showed a significant ability to relieve orthodontic pain at 24, 48, and 72 hours after insertion of the initial orthodontic wire in female subjects. Therefore, PEMF may be an effective measure to reduce pain caused by initial tooth movement.

References (37)

  • M.L. Jones et al.

    Initial tooth movement: force application and pain—relationship?

    Am J Orthod

    (1985)
  • I. Qamruddin et al.

    Effect of a single dose of low-level laser therapy on spontaneous and chewing pain caused by elastomeric separators

    Am J Orthod Dentofacial Orthop

    (2016)
  • P. Scheurer et al.

    Perception of pain as a result of orthodontic treatment with fixed appliances

    Eur J Orthod

    (1996)
  • K.K. Lew

    Attitudes and perceptions of adults towards orthodontic treatment in an Asian community

    Community Dent Oral Epidemiol

    (1993)
  • L.W. White

    Pain and cooperation in orthodontic treatment

    J Clin Orthod

    (1984)
  • S. Marie et al.

    Vibratory stimulation as a method of reducing pain after orthodontic appliance adjustment

    J Clin Orthod

    (2003)
  • I. Marini et al.

    The effect of diode superpulsed low-level laser therapy on experimental orthodontic pain caused by elastomeric separators: a randomized controlled clinical trial

    Lasers Med Sci

    (2015)
  • J.Y. Hwang et al.

    Effectiveness of thera-bite wafers in reducing pain

    J Clin Orthod

    (1994)
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    All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported.

    Supported by Wonkwang University in 2017.

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