Assessment of the changes in arch perimeter and irregularity in the mandibular arch during initial alignment with the AcceleDent Aura appliance vs no appliance in adolescents: A single-blind randomized clinical trial

Periodontal response to nonsurgical accelerated orthodontic tooth movement

Tooth movement is a complex process involving the vascularization of the tissues, remodeling of the bone cells, and periodontal ligament fibroblasts under the hormonal and neuronal regulation mechanisms in response to mechanical force application. Therefore, it will inevitably impact periodontal tissues. Prolonged treatment can lead to adverse effects on teeth and periodontal tissues, prompting the development of various methods to reduce the length of orthodontic treatment. These methods are surgical or nonsurgical interventions applied simultaneously within the orthodontic treatment. The main target of nonsurgical approaches is modulating the response of the periodontal tissues to the orthodontic force. They stimulate osteoclasts and osteoclastic bone resorption in a controlled manner to facilitate tooth movement. Among various nonsurgical methods, the most promising clinical results have been achieved with photobiomodulation (PBM) therapy. Clinical data on electric/magnetic stimulation, pharmacologic administrations, and vibration forces indicate the need for further studies to improve their efficiency. This growing field will lead to a paradigm shift as we understand the biological response to these approaches and their adoption in clinical practice. This review will specifically focus on the impact of nonsurgical methods on periodontal tissues, providing a comprehensive understanding of this significant and understudied aspect of orthodontic care.

Effect of applying intermittent force with and without vibration on orthodontic tooth movement

PURPOSE

This study aimed to determine whether orthodontic tooth movement could be accelerated by applying an intermittent force protocol. It also examined the effect of applying additional vibrational forces on orthodontic tooth movement and root resorption rates.

METHODS

This study included 24 patients (16 males and 8 females) who underwent orthodontic treatment involving first premolar extraction and distal movement of the canines in the maxilla. A Hycon device (Adenta GmbH, Gilching, Germany) was used for canine distalization in all patients. The patients were randomly divided into two groups: one group received 20 min of vibration per day using the AcceleDent device (OrthoAccel Technologies, Inc., Bellaire, TX, USA), while the other group received no vibration. In addition, a split-mouth design was used: an activation-only force protocol was applied on one side, and an intermittent activation-deactivation-activation (ADA) protocol was applied on the other. The duration required for complete canine tooth distalization on each side was calculated. In addition, the effect of vibration on the orthodontically induced root resorption was examined.

RESULTS

The intermittent ADA protocol significantly accelerated orthodontic tooth movement compared to the activation-only protocol (p < 0.05). The application of additional vibration did not affect the orthodontic tooth movement rate (p > 0.05).

CONCLUSIONS

Using a Hycon device and following an ADA protocol provided significantly faster canine distalization than the activation-only protocol (p < 0.05). This intermittent force method proved very effective in closing the spaces. However, vibration did not significantly affect the orthodontic tooth movement rate (p > 0.05).

Effectiveness of low frequency vibration on the rate of canine retraction: a randomized controlled clinical trial

To investigate the effectiveness of AcceleDent Aura vibrating device on the rate of canine retraction. Thirty-two patients requiring extraction of upper first premolars and canine retraction were randomly allocated with a 1:1 ratio into either no-appliance group or the AcceleDent Aura appliance group. Canine retraction was done applying 150gm of retraction force using NiTi coil springs on 16 × 22 stainless steel archwires. The duration of the study was 4 months. Models were collected and digitized directly after extraction of upper first premolars and at monthly intervals during canine retraction for recording the monthly as well as the total distance moved by the canine. Digitized models were superimposed on the initial model and data were statistically analyzed. Anchorage loss, rotation, tipping, torque and root condition were evaluated using cone beam computed tomography imaging. Pain was evaluated by visual analog scale. No patients were dropped-out during this study. There was no statistically significant difference between both groups regarding the total distance travelled by the canine (P = 0.436), as well as the rate of canine retraction per month (P = 0.17). Root condition was the same for the two groups. Regarding the pain level, there was no statistically significant difference between the two groups at day 0 (P = 0.721), after 24 h (P = 0.882), after 72 h (P = 0.378) and after 7 days (P = 0.964). AcceleDent Aura was not able to accelerate orthodontic tooth movement. Pain level couldn't be reduced by vibrational force with an AcceleDent device during orthodontic treatment. Root condition was not affected by the vibrational forces.

Proposal regarding potential causes related to certain complications with dental implants and adjacent natural teeth: Physics applied to prosthodontics

PURPOSE

Complications can and do occur with implants and their restorations with causes having been proposed for some single implant complications but not for others.

METHODS

A review of pertinent literature was conducted. A PubMed search of vibration, movement, and dentistry had 175 citations, while stress waves, movement, and dentistry had zero citations as did stress waves, movement. This paper discusses the physics of vibration, elastic and inelastic collision, and stress waves as potentially causative factors related to clinical complications.

RESULTS

Multiple potential causes for interproximal contact loss have been presented, but it has not been fully understood. Likewise, theories have been suggested regarding the intrusion of natural teeth when they are connected to an implant as part of a fixed partial denture as well as intrusion when a tooth is located between adjacent implants, but the process of intrusion, and resultant extrusion, is not fully understood. A third complication with single implants and their crowns is abutment screw loosening with several of the clinical characteristics having been discussed but without determining the underlying process(es).

CONCLUSIONS

Interproximal contact loss, natural tooth intrusion, and abutment screw loosening are common complications that occur with implant retained restorations. Occlusion is a significant confounding variable. The hypothesis is that vibration, or possibly stress waves, generated from occlusal impact forces on implant crowns and transmitted to adjacent teeth, are the causative factors in these events. Since occlusion appears to play a role in these complications, it is recommended that occlusal contacts provide centralized stability on implant crowns and not be located on any inclined surfaces that transmit lateral forces that could be transmitted to an adjacent tooth and cause interproximal contact loss or intrusion. The intensity, form, and location of proximal contacts between a natural tooth located between adjacent single implant crowns seem to play a role in the intrusion of the natural tooth. Currently, there is a lack of information about the underlying mechanisms related to these occurrences and research is needed to define any confounding variables.

Vibrational Force on Accelerating Orthodontic Tooth Movement: A Systematic Review and Meta-Analysis

This study aimed to systematically gather and analyze the current level of evidence for the effectiveness of the vibrational force in accelerating orthodontic tooth movement (OTM). This systematic review was conducted using three electronic databases: Scopus, PubMed, and Google Scholar until March 2022. The search was done through the following journals: European Journal of Orthodontics, American Journal of Orthodontics and Dentofacial Orthopedics, The Angle Orthodontist, Progress in Orthodontics, and Seminars in Orthodontics. Human or animal studies that have evaluated the effect of vibrational force on the rate of OTM were selected. A meta-analysis was performed for the rate of canine movement per month. Database research, elimination of duplicate studies, data extraction, and risk of bias assessment were performed by authors independently and in duplication. A fixed and random-effect meta-analysis was performed to evaluate the effect of vibrational forces. A total of 19 studies (6 animal and 13 human studies) that met the inclusion criteria were included. Meta-analysis was performed based on four human clinical trials. Three out of four studies showed no significant difference in the rate of canine movement between vibrational force and control groups. The limitation of this study was the small sample size and significant heterogeneity among the studies. Although vibrational forces have been shown to accelerate OTM in experimental studies, the results are inconsistent in clinical studies. The inability to apply desired peak load to the targeted teeth may be the main factor in inconsistent clinical outcomes.

Non-surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic treatment

BACKGROUND

Deviation from a normal bite can be defined as malocclusion. Orthodontic treatment takes 20 months on average to correct malocclusion. Accelerating the rate of tooth movement may help to reduce the duration of orthodontic treatment and associated unwanted effects including orthodontically induced inflammatory root resorption (OIIRR), demineralisation and reduced patient motivation and compliance. Several non-surgical adjuncts have been advocated with the aim of accelerating the rate of orthodontic tooth movement (OTM).         OBJECTIVES: To assess the effect of non-surgical adjunctive interventions on the rate of orthodontic tooth movement and the overall duration of treatment.

SEARCH METHODS

An information specialist searched five bibliographic databases up to 6 September 2022 and used additional search methods to identify published, unpublished and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of people receiving orthodontic treatment using fixed or removable appliances along with non-surgical adjunctive interventions to accelerate tooth movement. We excluded split-mouth studies and studies that involved people who were treated with orthognathic surgery, or who had cleft lip or palate, or other craniofacial syndromes or deformities.

DATA COLLECTION AND ANALYSIS

Two review authors were responsible for study selection, risk of bias assessment and data extraction; they carried out these tasks independently. Disagreements were resolved by discussion amongst the review team to reach consensus.  MAIN RESULTS: We included 23 studies, none of which were rated as low risk of bias overall. We categorised the included studies as testing light vibrational forces or photobiomodulation, the latter including low level laser therapy and light emitting diode. The studies assessed non-surgical interventions added to fixed or removable orthodontic appliances compared to treatment without the adjunct. A total of 1027 participants (children and adults) were recruited with loss to follow-up ranging from 0% to 27% of the original samples.  Certainty of the evidence For all comparisons and outcomes presented below, the certainty of the evidence is low to very low. Light vibrational forces  Eleven studies assessed how applying light vibrational forces (LVF) affected orthodontic tooth movement (OTM). There was no evidence of a difference between the intervention and control groups for duration of orthodontic treatment (MD -0.61 months, 95% confidence interval (CI) -2.44 to 1.22; 2 studies, 77 participants); total number of orthodontic appliance adjustment visits (MD -0.32 visits, 95% CI -1.69 to 1.05; 2 studies, 77 participants); orthodontic tooth movement during the early alignment stage (reduction of lower incisor irregularity (LII)) at 4-6 weeks (MD 0.12 mm, 95% CI -1.77 to 2.01; 3 studies, 144 participants), or 10-16 weeks (MD -0.18 mm, 95% CI -1.20 to 0.83; 4 studies, 175 participants); rate of canine distalisation (MD -0.01 mm/month, 95% CI -0.20 to 0.18; 2 studies, 40 participants); or rate of OTM during en masse space closure (MD 0.10 mm per month, 95% CI -0.08 to 0.29; 2 studies, 81 participants). No evidence of a difference was found between LVF and control groups in rate of OTM when using removable orthodontic aligners. Nor did the studies show evidence of a difference between groups for our secondary outcomes, including patient perception of pain, patient-reported need for analgesics at different stages of treatment and harms or side effects.  Photobiomodulation Ten studies assessed the effect of applying low level laser therapy (LLLT) on rate of OTM. We found that participants in the LLLT group had a statistically significantly shorter length of time for the teeth to align in the early stages of treatment (MD -50 days, 95% CI -58 to -42; 2 studies, 62 participants) and required fewer appointments (-2.3, 95% CI -2.5 to -2.0; 2 studies, 125 participants). There was no evidence of a difference between the LLLT and control groups in OTM when assessed as percentage reduction in LII in the first month of alignment (1.63%, 95% CI -2.60 to 5.86; 2 studies, 56 participants) or in the second month (percentage reduction MD 3.75%, 95% CI -1.74 to 9.24; 2 studies, 56 participants). However, LLLT resulted in an increase in OTM during the space closure stage in the maxillary arch (MD 0.18 mm/month, 95% CI 0.05 to 0.33; 1 study; 65 participants; very low level of certainty) and the mandibular arch (right side MD 0.16 mm/month, 95% CI 0.12 to 0.19; 1 study; 65 participants). In addition, LLLT resulted in an increased  rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; 1 study, 37 participants). These  findings were not clinically significant. The studies showed no evidence of a difference between groups for our secondary outcomes, including OIIRR, periodontal health and patient perception of pain at early stages of treatment. Two studies assessed the influence of applying light-emitting diode (LED) on OTM. Participants in the LED group required a significantly shorter time to align the mandibular arch compared to the control group (MD -24.50 days, 95% CI -42.45 to -6.55, 1 study, 34 participants). There is no evidence that LED application increased the rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; P = 0.28; 1 study, 39 participants ). In terms of secondary outcomes, one study assessed patient perception of pain and found no evidence of a difference between groups.   AUTHORS' CONCLUSIONS: The evidence from randomised controlled trials concerning the effectiveness of non-surgical interventions to accelerate orthodontic treatment is of low to very low certainty. It suggests that there is no additional benefit of light vibrational forces or photobiomodulation for reducing the duration of orthodontic treatment. Although there may be a limited benefit from photobiomodulation application for accelerating discrete treatment phases, these results have to be interpreted with caution due to their questionable clinical significance. Further well-designed, rigorous RCTs with longer follow-up periods spanning from start to completion of orthodontic treatment are required to determine whether non-surgical interventions may reduce the duration of orthodontic treatment by a clinically significant amount, with minimal adverse effects.

Pain profile during orthodontic levelling and alignment with fixed appliances reported in randomized trials: a systematic review with meta-analyses

OBJECTIVE

To assess the pain profile of patients in the levelling/alignment phase of orthodontic treatment, as reported from randomized clinical trials.

MATERIALS AND METHODS

Five databases were searched in September 2022 for randomized clinical trials assessing pain during levelling/alignment with a visual analogue scale (VAS). After duplicate study selection, data extraction, and risk-of-bias assessment, random effects meta-analyses of mean differences (MDs) and their 95% confidence intervals (CIs) were performed, followed by subgroup/meta-regression, and certainty analyses.

RESULTS

A total of 37 randomized trials including 2277 patients (40.3% male; mean age 17.5 years) were identified. Data indicated quick pain initiation after insertion of orthodontic appliances (n = 6; average = 12.4 mm VAS), a quick increase to a peak at day 1 (n = 29; average = 42.4 mm), and gradually daily decrease the first week until its end (n = 23; average = 9.0 mm). Every second patient reported analgesic use at least once this week (n = 8; 54.5%), with peak analgesic use at 6 h post-insertion (n = 2; 62.3%). Patients reported reduced pain in the evening compared to morning (n = 3; MD =  - 3.0 mm; 95%CI =  - 5.3, - 0.6; P = 0.01) and increased pain during chewing (n = 2; MD = 19.2 mm; 95% CI = 7.9, 30.4; P < 0.001) or occlusion of the back teeth (n = 2; MD = 12.4 mm; 95% CI = 1.4, 23.4; P = 0.3), while non-consistent effects were seen for patient age, sex, irregularity, or analgesic use. Subgroup analyses indicated increased pain among extraction cases and during treatment of the lower (rather than the upper) arch, while certainty around estimates was moderate to high.

CONCLUSIONS

Evidence indicated a specific pain profile during orthodontic levelling/alignment, without signs of consistent patient-related influencing factors.

Dynamic changes in tooth displacement and bone morphometry induced by orthodontic force

This study used a novel 3D analysis to longitudinally evaluate orthodontic tooth movement (OTM) and bone morphometry. Twelve-week-old male Wistar rats were subjected to OTM by applying a constant orthodontic force (OF) of 25cN between one of the upper first molars and a mini-screw. In vivo micro-CTs were taken before and after 10, 17, 24 and 31 days of force application, and superimposed by a novel and rigid voxel-based registration method. Then the tooth and alveolar bone segment at different time points became comparable in the same coordinate system, which facilitated the analysis of their dynamic changes in 3D. By comparison between time points and between OF and no OF sides, this study showed that the OTM rate was not constant through time, but conformed to a ‘V’ shape changing pattern. Besides, OF induced displacement of both loaded and unloaded teeth, and the latter mirrored the former in a delayed manner. In addition, bone morphometric changes synchronized with OTM rate changes, implying that a higher OTM rate was concomitant with more alveolar bone loss. The pressure and tension areas might not be in two opposite sides, but actually adjacent and connected. These findings might provide instructive evidence for both clinical, translational and basic research in orthodontics.

Orthodontic treatment for crowded teeth in children

BACKGROUND

Crowded teeth develop when there is not enough space in the jaws into which the teeth can erupt. Crowding can affect baby teeth (deciduous dentititon), adult teeth (permanent dentition), or both, and is a common reason for referral to an orthodontist. Crowded teeth can affect a child's self-esteem and quality of life. Early loss of baby teeth as a result of tooth decay or trauma, can lead to crowded permanent teeth. Crowding tends to increase with age, especially in the lower jaw.

OBJECTIVES

To assess the effects of orthodontic intervention for preventing or correcting crowded teeth in children. To test the null hypothesis that there are no differences in outcomes between different orthodontic interventions for preventing or correcting crowded teeth in children.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched four bibliographic databases up to 11 January 2021 and used additional search methods to identify published, unpublished and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated any active interventions to prevent or correct dental crowding in children and adolescents, such as orthodontic braces or extractions, compared to no or delayed treatment, placebo treatment or another active intervention. The studies had to include at least 80% of participants aged 16 years and under.

DATA COLLECTION AND ANALYSIS

Two review authors, independently and in duplicate, extracted information regarding methods, participants, interventions, outcomes, harms and results. We resolved any disagreements by liaising with a third review author. We used the Cochrane risk of bias tool to assess the risk of bias in the studies. We calculated mean differences (MDs) with 95% confidence intervals (CI) for continuous data and odds ratios (ORs) with 95% CIs for dichotomous data. We undertook meta-analysis when studies of similar comparisons reported comparable outcome measures, using the random-effects model. We used the I2 statistic as a measure of statistical heterogeneity.

MAIN RESULTS

Our search identified 24 RCTs that included 1512 participants, 1314 of whom were included in analyses. We assessed 23 studies as being at high risk of bias and one as unclear.  The studies investigated 17 comparisons. Twenty studies evaluated fixed appliances and auxiliaries (lower lingual arch, lower lip bumper, brackets, archwires, lacebacks, headgear and adjunctive vibrational appliances); two studies evaluated removable appliances and auxiliaries (Schwarz appliance, eruption guidance appliance); and two studies evaluated dental extractions (lower deciduous canines or third molars). The evidence should be interpreted cautiously as it is of very low certainty. Most interventions were evaluated by a single study. Fixed appliances and auxiliaries One study found that use of a lip bumper may reduce crowding in the early permanent dentition (MD -4.39 mm, 95% CI -5.07 to -3.71; 34 participants). One study evaluated lower lingual arch but did not measure amount of crowding. One study concluded that coaxial nickel-titanium (NiTi) archwires may cause more tooth movement in the lower arch than single-stranded NiTi archwires (MD 6.77 mm, 95% CI 5.55 to 7.99; 24 participants). Another study, comparing copper NiTi versus NiTi archwires, found NiTi to be more effective for reducing crowding (MD 0.49 mm, 95% CI 0.35 to 0.63, 66 participants). Single studies did not show evidence of one type of archwire being better than another for Titinol versus Nitinol; nickel-titanium versus stainless steel or multistrand stainless steel; and multistranded stainless steel versus stainless steel.  Nor did single studies find evidence of a difference in amount of crowding between self-ligating and conventional brackets, active and passive self-ligating brackets, lacebacks added to fixed appliances versus fixed appliances alone, or cervical pull headgear versus minor interceptive procedures. Meta-analysis of two studies showed no evidence that adding vibrational appliances to fixed appliances reduces crowding at 8 to 10 weeks (MD 0.24 mm, 95% CI -0.81 to 1.30; 119 participants). Removable appliances and auxiliaries One study found use of the Schwarz appliance may be effective at treating dental crowding in the lower arch (MD -2.14 mm, 95% CI -2.79 to -1.49; 28 participants). Another study found an eruption guidance appliance may reduce the number of children with crowded teeth after one year of treatment (OR 0.19, 95% CI 0.05 to 0.68; 46 participants); however, this may have been due to an increase in lower incisor proclination in the treated group. Whether these gains were maintained in the longer term was not assessed. Dental extractions One study found that extracting children's lower deciduous canines had more effect on crowding after one year than no treatment (MD -4.76 mm, 95 CI -6.24 to -3.28; 83 participants), but this was alongside a reduction in arch length. One study found that extracting wisdom teeth did not seem to reduce crowding any more than leaving them in the mouth (MD -0.30 mm, 95% CI -1.30 to 0.70; 77 participants).

AUTHORS' CONCLUSIONS

Most interventions were assessed by single, small studies. We found very low-certainty evidence that lip bumper, used in the mixed dentition, may be effective for preventing crowding in the early permanent dentition, and a Schwarz appliance may reduce crowding in the lower arch. We also found very low-certainty evidence that coaxial NiTi may be better at reducing crowding than single-stranded NiTi, and that NiTi may be better than copper NiTi. As the current evidence is of very low certainty, our findings may change with future research.

The effect of 12 weeks of mechanical vibration on root resorption: a micro-CT study

OBJECTIVE

The aim was to investigate the effect of mechanical vibration on root resorption with or without orthodontic force application.

MATERIAL AND METHODS

Twenty patients who required maxillary premolar extractions as part of orthodontic treatment were randomly divided into two groups of 10: no-force group and force group. Using a split-mouth procedure, each patient's maxillary first premolar teeth were randomly assigned as either vibration or control side for both groups. A buccally directed vibration of 50 Hz, with an Oral-B HummingBird device, was applied to the maxillary first premolar for 10 min/day for 12 weeks. After the force application period, the maxillary first premolars were extracted and scanned with micro-computed tomography. Fiji (ImageJ), performing slice-by-slice quantitative volumetric measurements, was used for resorption crater calculation. Total crater volumes were compared with the Wilcoxon and Mann-Whitney U tests.

RESULTS

The total crater volumes in the force and no-force groups were 0.476 mm3 and 0.017 mm3 on the vibration side and 0.462 mm3 and 0.031 mm3 on the control side, respectively. There was no statistical difference between the vibration and control sides (P > 0.05). There was more resorption by volume in the force group when compared to the no-force group (P < 0.05).

CONCLUSION

Mechanical vibration did not have a beneficial effect on reducing root resorption; however, force application caused significant root resorption.

Does observational study on the effectiveness of the Twin Blocks overestimate or underestimate the results? A comparative analysis of retrospective samples versus randomized controlled trial

BACKGROUND AND OBJECTIVES

Class II malocclusion is one of the most common orthodontic problems. The Twin Block appliance has proven to be the most popular appliance for the correction of these malocclusions. Although randomized controlled trials (RCTs) on the Twin Block appliance have reported the changes to be mainly dentoalveolar, several nonrandomized studies have reported a significant skeletal improvement in these patients. Hence, the aim of this study was to compare the effectiveness of Twin Block appliance evaluated using an RCT or retrospectively selected cases (RSC) for the treatment of Class II Division 1 malocclusion in an adolescent population.

METHODS

This was a retrospective study. The results for an RCT were selected from a UK Class II multicenter study. Sixty-three patients from the trial were included. This group was matched with retrospectively selected Class II cases treated with a Twin Block functional appliance and their results submitted for Membership in Orthodontics examination in the United Kingdom, from four centers. The primary outcome was skeletal measurement ANB (A point, nasion, B point). Secondary outcomes included final peer assessment rating (PAR) scores and final overjet. Intrarater reliability of measurements was assessed. Independent samples t-test was carried out to look at the difference between the groups.

RESULTS

The reliability assessment showed excellent agreement for all measurements. The data were normally distributed. There was a statistically significant difference favoring the RSC group for final overjet (mean difference [MD] = 1.068, 95% confidence interval [CI] -0.67 to 1.47, P = 0.000) and final PAR (MD = 4.0, 95% CI -0.79 to 5.5, P = 0.000). There was no significant difference in the scores for final ANB (MD = 0.34, 95% CI -0.39 to 1.07, P = 0.33).

CONCLUSION

The RSCs show significantly improved overjet and PAR scores at the end of treatment and no statistically significant difference for skeletal change. The study raises the question of a potential role of observational studies in evaluating the effect of an intervention in orthodontics.

Performance comparison of vibration devices on orthodontic tooth movement - A systematic review and meta-analysis

Background

To evaluate the efficiency of vibratory devices in altering rate of orthodontic tooth movement.

Methods

A literature search up to January 31, 2020 was conducted in three electronic databases: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL) and Science Direct, to identify studies on vibratory devices reporting any alteration in tooth movement as a primary outcome. Only articles published in English language were included. A meta-analysis was done to compare the amount of tooth movement (in mm) in patients treated with vibratory devices compared to control groups, to quantify weighted treatment effects.

Results

A total of two split mouth studies, six parallel arm randomized control trials (RCT) one split mouth RCT, and three regular RCTs were assessed qualitatively. Quantitative assessment was done for 8 randomized trials using a forest plot (310 patients). Pooled data showed increase in the amount of tooth movement by 0.34 ​mm (95% CI:0.25,0.42). There was a statistically significant difference noted for this result at p ​< ​0.00001.

Conclusion

Current evidence suggests a moderate to high level of certainty in regard to included studies in this systematic review and meta-analysis. Vibratory devices when used in conjunction with fixed orthodontic appliances show significant increase in the rate of tooth movement. These devices can be used by clinicians to reduce treatment duration and patient discomfort.

PROSPERO registration

CRD42020169675.

Comparative assessment of the rate of orthodontic tooth movement in adolescent patients undergoing treatment by first bicuspid extraction and en mass retraction, associated with low-frequency mechanical vibrations in passive self-ligating and conventional brackets: A randomized controlled trial

BACKGROUND

Low-frequency vibrations are one of the many non-surgical modalities aimed at increasing the rate of orthodontic tooth movement.

OBJECTIVE

The present trial was conducted to assess the efficacy of low-frequency vibrations in increasing the rate of orthodontic tooth movement in adolescent patients undergoing fixed mechanotherapy with passive self-ligating brackets and conventional brackets.

MATERIALS AND METHODS

Setting and sample population: department of orthodontics and dentofacial orthopaedics in a nationally accredited dental college. Participants, study design and methods: 65 patients were randomly allocated to three groups. Two experimental groups consisted of passive self-ligating and conventionally ligated appliances received low-frequency vibrations. The control group did not receive any vibrations. Allocation ratio was 1:1:1.32. Eligibility criteria: adolescent patients with sound and healthy dentition, incisor irregularity<5mm.

PRIMARY OUTCOME

rate of orthodontic tooth movement in mm/month. Randomization and blinding: computer-generated random allocation sequencing was done and data assessor was blinded.

STATISTICS

the Q-Q plot and Shapiro-Wilks test judged the normality of the data. The parametric test included ANCOVA and post-hoc analysis.

RESULTS

No statistically significant enhancement of tooth movement was seen in the experimental groups, when comparison was done with the control group P>0.05. Comparison between the two experimental groups did not reveal any significant difference either.

CONCLUSION

No statistically significant increase of orthodontic tooth movement was seen with low-frequency vibrations and the mode of ligation did not have any effect in increasing the rate of tooth movement either.

Effect of verbal and written information on pain perception in patients undergoing fixed orthodontic treatment: a randomized controlled trial

BACKGROUND

Pain can discourage patients from seeking orthodontic treatment or compromise their compliance during therapy.

OBJECTIVES

To determine the effects of verbal and written information on orthodontic pain after fixed appliance placement.

TRIAL DESIGN

Two-arm parallel design randomized controlled trial.

METHODS

Healthy adolescents with permanent dentition enrolled for orthodontic treatment were assigned to the study or control group using computer-generated random lists and allocation concealment with sealed envelopes. Participants completed baseline questionnaires to assess anxiety (State-Trait Anxiety Inventory Trait Version, Form X-2) and somatosensory amplification (Somatosensory Amplification Scale). Brackets were placed in the maxillary arch, from first molar to first molar, and an Australian archwire 0.012 inch was used for alignment. General verbal information on orthodontic treatment was given to all patients by the same clinician. Participants included in the study group received also detailed verbal instructions on orthodontic pain together with a take-home information leaflet by another clinician. Outcome included assessments of pain intensity with a Numerical Rating Scale (NRS) on the day of appliance placement (Day 1, bedtime) and twice a day for the following 6 days (Day 2 to Day 7, morning, bedtime), and analgesic consumption. Participants, statistician, and clinicians who gave general verbal information on orthodontic treatment and instructions about how to score pain intensity were blinded to group assignment.

RESULTS

Sixty patients were assigned to the study (n = 30, mean age: 15.4 ± 1.3 years) or control group (n = 30, mean age: 14.7 ± 3.2 years). At baseline, no significant between-group differences were present in terms of anxiety and somatosensory amplification. Orthodontic pain scores were significantly lower in the study group compared with the control one, at bedtime on Day 1 (P < 0.05) and in the morning of Day 2 (P < 0.01). No significant between-group differences were found in following measurements. Overall, analgesic consumption was significantly lower in study compared with the control (P < 0.01).

CONCLUSION

A combination of verbal and written information on orthodontic pain after placement of fixed appliances reduced patient's self-reported pain in the early stages.

REGISTRATION

This study was not registered.

Biomarkers of orthodontic tooth movement with fixed appliances and vibration appliance therapy: a pilot study

INTRODUCTION

The aim of this study was to investigate the effect of supplemental vibratory force on biomarkers of bone remodelling during orthodontic tooth movement, the rate of mandibular anterior alignment (RMAA), and compliance with a vibration device.

DESIGN, SETTINGS, AND PARTICIPANTS

Forty patients between the ages 15-35 undergoing fixed appliance treatment that presented to a university orthodontic clinic were randomly allocated to supplemental use of an intraoral vibrational device (n = 20, AcceleDent®) or fixed appliance only (n = 20). Salivary multiplex assay was completed to analyse the concentration of selected biomarkers of bone remodelling before treatment (T0) and at three following time points (T1, T2, T3), 4-6 weeks apart. Irregularity of the mandibular anterior teeth and compliance was assessed at the same trial time points. Data were analysed blindly on an intention-to-treat basis with descriptive statistics, Mann-Whitney U-test, Wilcoxon signed-rank test, and linear mixed effects regression modelling.

RESULTS

No difference in the changes in salivary biomarkers of bone remodelling and RMAA between groups at any time point over the trial duration was observed. No correlation was found between changes in irregularity and biomarker level from baseline to another time point. Lastly, there was no association between RMAA and compliance with the AcceleDent® device.

CONCLUSIONS

Supplemental vibratory force during orthodontic treatment with fixed appliances does not affect biomarkers of bone remodelling or the RMAA.

LIMITATIONS

The main limitation of the study was the small sample size and the large variability in the salivary biomarkers.

HARMS

No harms were observed during the duration of the trial.

PROTOCOL

The protocol was not published prior to trial commencement.

REGISTRATION

The study was registered in Clinical Trials.gov (NCT02119455) first posted on April 2014.

Does low-frequency vibration have an effect on aligner treatment? A single-centre, randomized controlled trial

BACKGROUND

Low-frequency vibrations have been proposed as a means of accelerating tooth movement and reducing orthodontic treatment times.

OBJECTIVE

To determine any differences in the accuracy of dental movement in patients treated with a low-frequency vibration aligner protocol and/or by reducing the aligner replacement interval with respect to a conventional protocol.

DESIGN

This trial was designed as a single-centre, randomized controlled clinical trial.

METHODS

Participants: Patients (aged 27.1 ± 9.0 years) who required orthodontic treatment with aligners. Randomization: Patients were randomly allocated to three arms as determined by a computer-randomization scheme. Group A were assigned a conventional protocol (aligners replaced every 14 days); group B also used a low-frequency vibration device for 20 minutes per day; group C followed the same vibration protocol but replaced their aligners every 7 days. Blinding: The operator who performed the set-up and the one who analysed the data were blinded to the group of the patients. Outcome: Pre- and post-treatment digital models were analysed using VAM software to identify the accuracy/imprecision of dental movements. One-way analysis of variance (P < 0.05) and the Bonferroni post hoc test were used to identify any statistically significant differences between the three arms in terms of the accuracy of tooth movement versus the prescription.

RESULTS

Numbers analysed: A total of 45 patients (15 for group) were analysed (i.e. 2286 dental movements). Outcome: No statistically significant differences emerged between groups A and C in the upper arch, or among groups A, B, and C in the lower. Group B displayed significantly greater accuracy with respect to group A in upper incisor rotation (P = 0.016), and to group C in vestibulolingual (P = 0.007) and mesiodistal tipping (P = 0.029) of the upper canines, and vestibulolingual tipping of the upper molars (P = 0.0001). Harms: No adverse events or side-effects were registered.

CONCLUSIONS

Considering all tooth and movement types of the 45 participants, the mean total imprecision was 2.1 ± 0.9 degrees, with respect to a mean prescription of 5.7 ± 2.2 degrees. There was no difference in accuracy between replacing the aligners accompanied by low-frequency vibration every 7 days and replacing them every 14 days without vibration. Moreover, low-frequency vibration seemed to improve the accuracy of a conventional protocol in terms of upper incisor rotation.

TRIAL REGISTRATION

The German Clinical Trials Register (DRK00015613).

The effectiveness of supplemental vibrational force on enhancing orthodontic treatment. A systematic review

BACKGROUND AND OBJECTIVES

The results from the literature regarding the influence of supplemental vibrational forces (SVFs) on orthodontic treatment are controversial. Therefore, this systematic review aimed to evaluate whether SVFs have positive effects, such as in accelerating tooth movement, alleviating pain, and preventing root resorption, in orthodontic patients.

SEARCH METHODS

Searches through five electronic databases (PubMed, MEDLINE, EMBASE, Web of Science, and Cochrane Central) were complemented by hand searches up to January, 2019.

SELECTION CRITERIA

Randomized controlled trials and controlled clinical trials reporting on the effects of SVFs in orthodontic patients in English were included.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, and a risk of bias assessment were independently performed by two reviewers. Study characteristics and outcomes were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A qualitative analysis of the effects of SVFs on orthodontic tooth movement, pain experience, and root resorption was conducted.

RESULTS

Thirteen studies, including nine clinical trials, were eligible for inclusion in the systematic review. There was no significant evidence to support the positive effects of SVFs in orthodontic patients, neither in accelerating tooth movement nor in alleviating pain experience. According to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria, the quality of the evidence was very low for all the outcomes in the qualitative analysis.

LIMITATIONS

The results of this systematic review are based on a limited number of studies and the methodological heterogeneity and non-comparability of original outcomes made it difficult to conduct a meta-analysis.

CONCLUSIONS

There is insufficient evidence to support the claim that SVFs have positive clinical advantages in the alignment of the anterior teeth. The potential positive effects of vibrational forces on space closure, pain experience, and root resorption in orthodontic patients are inconclusive with no sufficient information at present. High-quality clinical trials with larger sample sizes are needed to find more comprehensive evidence of the potential positive effects of vibrational forces.

REGISTRATION

The protocol for this systematic review was registered on PROSPERO (CRD42018098788).

FUNDING

This study has not received any contributions from private or public funding agencies.

CONFLICT OF INTEREST

None.

Effects of mechanical vibrations on maxillary canine retraction and perceived pain: a pilot, single-center, randomized-controlled clinical trial

The aim of this study was to investigate the effect of mechanical vibratory stimulation on maxillary canine retraction and pain perception in adolescents undergoing full-fixed orthodontic treatment with extraction. A pilot randomized-controlled clinical trial was conducted in one university orthodontic clinic. Twenty-one healthy adolescents who underwent full-fixed orthodontic treatment with maxillary first-premolar extraction were recruited. Subjects were randomly assigned to the experimental group (N = 10) that used a mechanical vibration device (AcceleDent Aura, OrthoAccel Technologies, Inc.) or the control group (N = 11) that did not receive a vibration device. The evaluation timepoints were T₀ = day of initial canine retraction; T₁ = 4 weeks post-initiation; T₂ = 8 weeks post-initiation; and T₃ = 12 weeks post-initiation. Three-dimensional palatal landmark superimpositions were made to assess amount of tooth movement (mm) at each visit, monthly rate of tooth movement (mm), and perceived pain levels (VAS scores). The total amount of tooth movement was observed in the control versus experimental groups, respectively, as 1.12 ± 0.22 mm versus 1.39 ± 0.36 mm at 4 weeks (p = 0.058), 2.59 ± 0.37 mm versus 2.49 ± 0.76 mm at 8 weeks (p = 0.702), and 3.54 ± 0.23 mm versus 3.37 ± 1.37 mm at 12 weeks (p = 0.716). The rate of tooth movement was 1.21 ± 0.32 mm/month in the control and 1.12 ± 0.20 mm/month in the experimental groups, which was not statistically significant at any of the timepoints and neither was the level of pain. This study found no statistically significant differences in canine retraction and pain perception between the experimental and control groups. We propose that further optimization of accelerated tooth movement with mechanical vibration devices is necessary.

Effectiveness and importance of powered tooth brushes in tooth movement

Introduction:

Effectiveness of vibratory stimulus from a commonly available battery-powered tooth brush in accelerating orthodontic tooth movement was tested by a randomized controlled split-mouth study.

Materials and Methods:

Twenty-three subjects with bimaxillary protrusion, requiring extraction of all first premolars and requiring maximum anchorage, were chosen. After initial leveling and aligning, miniscrews were placed between the first molar and the second premolar in the maxillary right and left quadrants and loaded with 150-g nickel–titanium closed-coil springs for individual canine retraction. Additional 5 min of vibratory stimulus thrice daily was applied on the experimental side. The mean treatment duration was 3 months.

Results:

There was no significant difference of means of the canine distal movement between the experimental and the control sides (P = 0.70).

Conclusion:

Application of vibratory stimulus with powered tooth brush during canine retraction was not seen to have an acceleratory effect on orthodontic tooth movement.

Effectiveness of using a Vibrating Device in Accelerating Orthodontic Tooth Movement: A Systematic Review and Meta-Analysis

Objective

The aim of current systematic review was to evaluate the efficiency of the vibrating devices in accelerating orthodontic tooth movement.

Methods

A systemic unrestricted search was done in three electronic databases up to July 2018. A manual search was also performed. Eligibility criteria included Randomized clinical trials (RCTs), quasi randomized clinical trials and prospective controlled trials (CCTs) comparing the rate of the tooth movement with and without vibrating devices. The study characteristics and data extraction of the vibrating device group and control group were performed by two reviewers independently.

Results

Seven articles were eligible to be included in the qualitative analysis. Three of them were included in meta analysis. One hundred and five patients received vibrating device to accelerate orthodontic treatment while forty-nine patients received shame device and seventy-eight patients were control group.

Conclusion

There was no significant difference between vibrating devices group and control group. There is no evidence that vibrating appliances are effective in acceleration of orthodontic tooth movement.

Effects of two frequencies of vibration on the maxillary canine distalization rate and RANKL and OPG secretion: A randomized controlled trial

OBJECTIVES

To investigate the effects of 30 and 60 Hz vibratory stimulus on canine distalization and RANKL and OPG secretion.

SETTING AND SAMPLE POPULATION

Sixty patients requiring canine distalization at the Orthodontic Clinic, Prince of Songkla University.

MATERIALS AND METHODS

Patients were randomly assigned to 30 Hz vibration (n = 20), 60 Hz vibration (n = 20), or the control group (n = 20). Modified electric toothbrushes were used to apply vibration to the randomly selected canine for 20 min/day by the investigator combined with 60 cN continuous distalization force from day 1 to day 7. RANKL and OPG were analysed before (T1) and 24 hours (T2), 48 hours (T3) and 7 days (T4) after initiation of distalization. From day 8, vibratory devices were used by the subjects at home. Rate of canine distalization (T1 to 3 months after initiation [T5]) was calculated. Kruskal-Wallis tests were used for multiple comparisons (significance level, 0.05).

RESULTS

Canine distalization rate was not different between groups (median; 0.82, 0.87, and 0.83 mm/month for 30, 60 Hz, and control group, respectively; P > 0.05). No within- or between-group differences in RANKL and OPG were observed (P > 0.05), except RANKL on the compression side of the control group was significantly higher at T2, T3 and T4 than T1 (P < 0.001).

CONCLUSION

In the clinic, 30 and 60 Hz vibratory stimulus have no additive effect on rate of canine distalization rate, RANKL and OPG secretion or RANKL/OPG ratio.

Looking Beyond Traditional Metrics in Orthodontics: An Altmetric Study on the Most Discussed Articles on the Web

Objective

To evaluate the online visibility of the most popular orthodontic articles in Web platforms in relation to publication details and citations.

Materials and Methods

Altmetric Explorer (Altmetric LLP, London, UK) was searched for articles published in 11 orthodontic journals without time limits in publication and citation on social media. The 200 articles with the highest Altmetric Attention Score (AAS) were collected and screened for data related to publication (date, journal, access), authorship (number of authors, affiliation and origin of the corresponding author), and research (type, subject, funding). Citation counts were harvested from Scopus.

Results

The top 200 articles presented a median AAS of 8.0 (range: 5.0-196.0), and were mostly bookmarked in Mendeley (median: 16.6 references; range: 0-199.0). American Journal of Orthodontics & Dentofacial Orthopedics, European Journal of Orthodontics and The Angle Orthodontist contributed 86 per cent of the total number of research outputs. Studies investigating socio-demographics had significantly higher AAS compared to diagnostic studies (median AAS: 19.0; range: 7.0-34.0; versus median AAS: 6.0; range: 5.0-10.0. No other study parameter was found to be statistically significant. AAS did not correlate to the number of citations as reported in Scopus.

Limitations

The early stage of altmetrics and their complementary role in assessing together with the citation-based metrics the research impact need to be acknowledged in the interpretation of the results.

Conclusions

Visibility of orthodontic articles on the Web is not significantly correlated with citations. Studies on socio-demographics had significantly higher number of online mentions. More constructive online presence of orthodontic journals is needed to reinforce dissemination of research data among scholars and non-scholars.

Placebo hypoalgesic effects in pain: Potential applications in dental and orofacial pain management

Placebo and nocebo effects are present within every treatment and intervention, and can be purposefully enhanced and reduced, respectively, in order to improve patients' clinical outcomes. A plethora of research has been conducted on the mechanisms of placebo hypoalgesia and nocebo hyperalgesia in experimental and clinical settings. However, its implications in particular clinical settings such as orthodontic pain management remain underexplored. We conducted a search of the literature regarding placebo analgesia, orthodontic pain management, and orofacial and dental pain. Articles were qualitatively assessed and selected based on the scope of this narrative review. Although no studies investigating the extent of the implications of the placebo and nocebo phenomena in the orthodontic clinical setting were found, we herein present a comprehensive review on the influences of placebo and nocebo effects in experimental and clinical pain management, as well as on the potential for engaging placebo-related endogenous pain modulation for orthodontic pain management. Ethical considerations for the clinical application of placebos are discussed, and future research directions are presented.

Effect of supplemental vibration on orthodontic treatment with aligners: A randomized trial

INTRODUCTION

Supplemental vibration has been reported to accelerate orthodontic tooth movement and reduce discomfort. Our purpose was to investigate the effects of AcceleDent on Invisalign treatment. This randomized clinical trial was carried out in 2 orthodontic private practices with a 1:1 allocation ratio.

METHODS

Adult patients who were beginning their orthodontic treatment were randomly allocated to either an active (A) or a sham (B) AcceleDent Aura device (OrthoAccel Technologies, Inc. Houston, TX). All patients were placed on a 1-week aligner change regimen, and fit was evaluated every 3 weeks. The outcomes were the ability to complete the initial set of aligners and the incisor irregularity measurements for those who completed their regimen of aligners. In addition, aligner compliance, pain levels, and oral health-related quality of life data were gathered from questionnaires. The subjects, investigators, and assessors were all blinded to the treatment arms.

RESULTS

Twenty-seven subjects were randomized into 2 groups (A and B), 1 subject discontinued treatment, and 13 subjects were analyzed in each group. The Fisher exact test showed no significant difference in completion rates between the 2 groups (group A, 77%; group B, 85%; P = 1). Independent-sample t tests showed no significant difference between the final irregularity index or change in irregularity index between the 2 groups. Compliance was similar in both groups. The Wilcoxon rank sum test showed minimal differences in pain levels. Quality of life responses were similar in both groups. No serious harm was observed.

CONCLUSIONS

We found no evidence that the AcceleDent Aura device impacts the ability to complete a series of aligners with a 1-week change regimen or the final alignment achieved in adult patients. It also had no significant effect on the reduction of orthodontic pain or oral health-related quality of life parameters when used with Invisalign.

Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents

BACKGROUND

Prominent upper front teeth are a common problem affecting about a quarter of 12-year-old children in the UK. The condition develops when permanent teeth erupt. These teeth are more likely to be injured and their appearance can cause significant distress. Children are often referred to an orthodontist for treatment with dental braces to reduce the prominence of their teeth. If a child is referred at a young age, the orthodontist is faced with the dilemma of whether to treat the patient early or to wait and provide treatment in adolescence.

OBJECTIVES

To assess the effects of orthodontic treatment for prominent upper front teeth initiated when children are seven to 11 years old ('early treatment' in two phases) compared to in adolescence at around 12 to 16 years old ('late treatment' in one phase); to assess the effects of late treatment compared to no treatment; and to assess the effects of different types of orthodontic braces.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 27 September 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 8), MEDLINE Ovid (1946 to 27 September 2017), and Embase Ovid (1980 to 27 September 2017). The US National Institutes of Health Ongoing Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials of orthodontic treatments to correct prominent upper front teeth (Class II malocclusion) in children and adolescents. We included trials that compared early treatment in children (two-phase) with any type of orthodontic braces (removable, fixed, functional) or head-braces versus late treatment in adolescents (one-phase) with any type of orthodontic braces or head-braces, and trials that compared any type of orthodontic braces or head-braces versus no treatment or another type of orthodontic brace or appliance (where treatment started at a similar age in the intervention groups).We excluded trials involving participants with a cleft lip or palate, or other craniofacial deformity/syndrome, and trials that recruited patients who had previously received surgical treatment for their Class II malocclusion.

DATA COLLECTION AND ANALYSIS

Review authors screened the search results, extracted data and assessed risk of bias independently. We used odds ratios (ORs) and 95% confidence intervals (CIs) for dichotomous outcomes, and mean differences (MDs) and 95% CIs for continuous outcomes. We used the fixed-effect model for meta-analyses including two or three studies and the random-effects model for more than three studies.

MAIN RESULTS

We included 27 RCTs based on data from 1251 participants.Three trials compared early treatment with a functional appliance versus late treatment for overjet, ANB and incisal trauma. After phase one of early treatment (i.e. before the other group had received any intervention), there was a reduction in overjet and ANB reduction favouring treatment with a functional appliance; however, when both groups had completed treatment, there was no difference between groups in final overjet (MD 0.21, 95% CI -0.10 to 0.51, P = 0.18; 343 participants) (low-quality evidence) or ANB (MD -0.02, 95% CI -0.47 to 0.43; 347 participants) (moderate-quality evidence). Early treatment with functional appliances reduced the incidence of incisal trauma compared to late treatment (OR 0.56, 95% CI 0.33 to 0.95; 332 participants) (moderate-quality evidence). The difference in the incidence of incisal trauma was clinically important with 30% (51/171) of participants reporting new trauma in the late treatment group compared to only 19% (31/161) of participants who had received early treatment.Two trials compared early treatment using headgear versus late treatment. After phase one of early treatment, headgear had reduced overjet and ANB; however, when both groups had completed treatment, there was no evidence of a difference between groups in overjet (MD -0.22, 95% CI -0.56 to 0.12; 238 participants) (low-quality evidence) or ANB (MD -0.27, 95% CI -0.80 to 0.26; 231 participants) (low-quality evidence). Early (two-phase) treatment with headgear reduced the incidence of incisal trauma (OR 0.45, 95% CI 0.25 to 0.80; 237 participants) (low-quality evidence), with almost half the incidence of new incisal trauma (24/117) compared to the late treatment group (44/120).Seven trials compared late treatment with functional appliances versus no treatment. There was a reduction in final overjet with both fixed functional appliances (MD -5.46 mm, 95% CI -6.63 to -4.28; 2 trials, 61 participants) and removable functional appliances (MD -4.62, 95% CI -5.33 to -3.92; 3 trials, 122 participants) (low-quality evidence). There was no evidence of a difference in final ANB between fixed functional appliances and no treatment (MD -0.53°, 95% CI -1.27 to -0.22; 3 trials, 89 participants) (low-quality evidence), but removable functional appliances seemed to reduce ANB compared to no treatment (MD -2.37°, 95% CI -3.01 to -1.74; 2 trials, 99 participants) (low-quality evidence).Six trials compared orthodontic treatment for adolescents with Twin Block versus other appliances and found no difference in overjet (0.08 mm, 95% CI -0.60 to 0.76; 4 trials, 259 participants) (low-quality evidence). The reduction in ANB favoured treatment with a Twin Block (-0.56°, 95% CI -0.96 to -0.16; 6 trials, 320 participants) (low-quality evidence).Three trials compared orthodontic treatment for adolescents with removable functional appliances versus fixed functional appliances and found a reduction in overjet in favour of fixed appliances (0.74, 95% CI 0.15 to 1.33; two trials, 154 participants) (low-quality evidence), and a reduction in ANB in favour of removable appliances (-1.04°, 95% CI -1.60 to -0.49; 3 trials, 185 participants) (low-quality evidence).

AUTHORS' CONCLUSIONS

Evidence of low to moderate quality suggests that providing early orthodontic treatment for children with prominent upper front teeth is more effective for reducing the incidence of incisal trauma than providing one course of orthodontic treatment in adolescence. There appear to be no other advantages of providing early treatment when compared to late treatment. Low-quality evidence suggests that, compared to no treatment, late treatment in adolescence with functional appliances, is effective for reducing the prominence of upper front teeth.

The effectiveness of vibrational stimulus to accelerate orthodontic tooth movement: a systematic review

BACKGROUND

In recent years, it has been a hot research topic to accelerate orthodontic tooth movement (OTM) through vibration. This review was therefore aimed to systematically evaluate the available evidences on the efficacy of vibrational stimulus to accelerate OTM.

METHODS

Randomized controlled trials and controlled clinical trials that evaluated the efficacy of vibration on OTM acceleration were searched through electronic and manual search. Two review authors independently conducted the study inclusion, quality assessment and data extraction. The quality of synthesized evidence was assessed according to GRADE system.

RESULTS

Eight clinical trials were included in this systematic review. Four studies found that vibration did not enhance the rate of OTM during alignment phase. Two studies revealed that the use of vibratory stimulation accelerated canine retraction. No deleterious effects including pain perceptions and root resorptions were reported.

CONCLUSIONS

Within the limitations of this review, weak evidence indicates that vibrational stimulus is effective for accelerating canine retraction but not for alignment. The effects of vibration on pain intensity and root resorption during orthodontic treatment are inconclusive. Future high-quality clinical trials are needed before warranting recommendations to clinical application.

Accelerated orthodontic treatment - what's the evidence?

The demand and accessibility of orthodontic care has increased but has also been accompanied by patient requests for shorter treatment times. Longer orthodontic treatment increases the risk of decalcification, gingival recession, and root resorption and so shorter treatment times have multiple advantages as well as appealing to patient's desires. Numerous techniques and materials have been suggested to reduce treatment times but, in most cases, are based upon selected case reports with no prospective clinical trials to validate claims. The present review examines many of the current options purported to accelerate orthodontic tooth movement and the level of evidence presently available. There is some evidence to suggest that low-level laser therapy and a corticotomy involving the raising of a muco-periosteal flap are associated with accelerated orthodontic tooth movement; however, the current level of evidence is low to moderate in quality. For this reason, further research is required before routine application could be recommended.

Non-pharmacological interventions for alleviating pain during orthodontic treatment

BACKGROUND

Pain is prevalent during orthodontics, particularly during the early stages of treatment. To ensure patient comfort and compliance during treatment, the prevention or management of pain is of major importance. While pharmacological means are the first line of treatment for alleviation of orthodontic pain, a range of non-pharmacological approaches have been proposed recently as viable alternatives.

OBJECTIVES

To assess the effects of non-pharmacological interventions to alleviate pain associated with orthodontic treatment.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 6 October 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 9), MEDLINE Ovid (1946 to 6 October 2016), Embase Ovid (1980 to 6 October 2016) and EThOS (to 6 October 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing a non-pharmacological orthodontic pain intervention to a placebo, no intervention or another non-pharmacological pain intervention were eligible for inclusion. We included any type of orthodontic treatment but excluded trials involving the use of pre-emptive analgesia or pain relief following orthognathic (jaw) surgery or dental extractions in combination with orthodontic treatment. We excluded split-mouth trials (in which each participant receives two or more treatments, each to a separate section of the mouth) and cross-over trials.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed risk of bias and extracted data. We used the random-effects model and expressed results as mean differences (MD) with 95% confidence intervals (CI). We investigated heterogeneity with reference to both clinical and methodological factors.

MAIN RESULTS

We included 14 RCTs that randomised 931 participants. Interventions assessed included: low-level laser therapy (LLLT) (4 studies); vibratory devices (5 studies); chewing adjuncts (3 studies); brain wave music or cognitive behavioural therapy (1 study) and post-treatment communication in the form of a text message (1 study). Twelve studies involved self-report assessment of pain on a continuous scale and two studies used questionnaires to assess the nature, intensity and location of pain.We combined data from two studies involving 118 participants, which provided low-quality evidence that LLLT reduced pain at 24 hours by 20.27 mm (95% CI -24.50 to -16.04, P < 0.001; I² = 0%). LLLT also appeared to reduce pain at six hours, three days and seven days.Results for the other comparisons assessed are inconclusive as the quality of the evidence was very low. Vibratory devices were assessed in five studies (272 participants), four of which were at high risk of bias and one unclear. Chewing adjuncts (chewing gum or a bite wafer) were evaluated in three studies (181 participants); two studies were at high risk of bias and one was unclear. Brain wave music and cognitive behavioural therapy were evaluated in one trial (36 participants) assessed at unclear risk of bias. Post-treatment text messaging (39 participants) was evaluated in one study assessed at high risk of bias.Adverse effects were not measured in any of the studies.

AUTHORS' CONCLUSIONS

Overall, the results are inconclusive. Although available evidence suggests laser irradiation may help reduce pain during orthodontic treatment in the short term, this evidence is of low quality and therefore we cannot rely on the findings. Evidence for other non-pharmacological interventions is either very low quality or entirely lacking. Further prospective research is required to address the lack of reliable evidence concerning the effectiveness of a range of non-pharmacological interventions to manage orthodontic pain. Future studies should use prolonged follow-up and should measure costs and possible harms.