Abstract: We included two studies in this review, which were both assessed as being at high risk of bias. The two studies, involving a total of 111 participants, compared the use of Tooth Masseuse and OrthoAccel with conventional treatment mechanics during orthodontic alignment and canine retraction phases, respectively. Both studies included objective assessment of the amount or rate of tooth movement, but we were not able to meta-analyse this data as they used different outcome measurements at different stages of the orthodontic treatment process. One study measured subjective evaluation of pain and discomfort and the other evaluated adverse effects. The studies did not directly report either the duration of orthodontic treatment or the number of visits during active treatment. Using the Tooth Masseuse with 111 Hz at 0.06 Newtons (N) for 20 minutes daily resulted in greater reduction in irregularity in the lower incisor region over 10 weeks, assessed using Little's Irregularity Index (LII) with a mean difference (MD) of 0.6 mm (95% confidence interval (CI) -0.94 to 2.34) when compared to the control group. Pain and discomfort increased at six to eight hours after arch wire placement and after seven days, with minimal difference between the intervention and control groups. No statistical tests were provided for either variable and the differences between the two groups were not clinically important. Using OrthoAccel with 30 Hz at 0.25 N for 20 minutes daily produced a higher rate of maxillary canine distalisation in comparison to the control group (MD 0.37 mm/month; 95% CI -0.07 to 0.81; P = 0.05). Whilst this difference suggested 50% faster tooth movement using the vibrational appliance, the absolute differences were marginal and deemed clinically unimportant. Similar levels of non-serious adverse effects were reported in the intervention and control groups with a risk ratio of 0.96 (95% CI 0.32 to 2.85). Overall, the quality of the evidence was very low and therefore we cannot rely on the findings. There is very little clinical research concerning the effectiveness of non-surgical interventions to accelerate orthodontic treatment. The available evidence is of very low quality and so it is not possible to determine if there is a positive effect of non-surgical adjunctive interventions to accelerate tooth movement. Although there have been claims that there may be a positive effect of light vibrational forces, results of the current studies do not reach either statistical or clinical significance. Further well-designed and rigorous RCTs with longer follow-up periods are required to determine whether non-surgical interventions may result in a clinically important reduction in the duration of orthodontic treatment, without any adverse effects.

Plain-language summary: Authors for the Cochrane Oral Health Group carried out this review of existing studies. The evidence on which it is based is current up to 26 November 2014. We included two studies involving a total of 111 participants in this review. A single orthodontic specialist in a private practice in Australia carried out one study, while the other study was conducted on patients treated by orthodontic residents in a university hospital seating in the United States of America. In one study, the age of participants ranged from 11 to 15 years old, and in the second, the average age of participants was 21 years. The studies evaluated the additional use of two devices that use light vibrational forces - Tooth Masseuse in people receiving conventional fixed appliance treatment during the tooth alignment stage and OrthoAccel for those receiving conventional fixed appliance treatment for the space closure stage in orthodontic treatment. Participants receiving additional treatment with the devices were compared to those receiving only the conventional treatment. The trials evaluated different aspects of orthodontic tooth movement and side effects. The studies evaluated three outcomes: rate of tooth movement; patient perception of pain and discomfort, and unwanted side effects. There were substantial differences between the studies, which meant that we were unable to combine the results. From the limited evidence available, it is not possible to establish if the use of vibrational forces during treatment with fixed orthodontic appliances has a significant beneficial or harmful effect on either the rate of orthodontic tooth movement or the duration of treatment. The quality of evidence was very low.