Vibratory stimulation increases interleukin-1 beta secretion during orthodontic tooth movement

Maintaining Hygiene in Orthodontic Miniscrews: Patient Management and Protocols-A Literature Review

BACKGROUND

Oral hygiene is crucial for the success of orthodontic therapy involving temporary anchoring devices like miniscrews. Plaque buildup, exacerbated by orthodontic appliances, causes inflammation that can undermine treatment outcomes. Individualized prevention plans based on patient risk factors are essential. This review emphasizes the importance of oral hygiene in orthodontic therapy with miniscrews, identifies optimal devices for ensuring long-term stability, and explores protocols for high-risk patients.

MATERIALS AND METHODS

A comprehensive search was conducted on two primary databases, PubMed and Google Scholar, for relevant articles on oral hygiene and inflammation. Fourteen articles meeting the inclusion criteria were selected, covering topics such as "orthodontic miniscrew", "miniscrew and laser", "miniscrew and mouthwash", "electric toothbrush", and "GBT".

RESULTS

Inflammation can compromise miniscrew stability by damaging surrounding bone. Miniscrews of 10 mm length have lower failure rates due to better bone contact and stability. Chlorhexidine reduces inflammation risk and inhibits epithelialization around the implant head. Laser therapy enhances miniscrew stability and reduces inflammation. Chitosan effectively suppresses inflammatory mediators and prevents microorganism adhesion. Both sonic and roto-oscillating electric toothbrushes remove plaque effectively, with roto-oscillating brushes showing superior results. The Guided Biofilm Therapy (GBT) protocol offers professional hygiene benefits similar to traditional methods, with improved patient engagement and motivation.

CONCLUSIONS

Home oral hygiene maintenance is paramount for preventing inflammatory complications. Professional interventions such as diode laser usage, particularly in adult patients with a history of periodontitis or underlying systemic conditions, can mitigate orthodontic therapy failure risks. The GBT protocol fosters a more comfortable and participatory professional hygiene experience for patients, promoting better oral health awareness and compliance.

The gingival crevicular fluid biomarkers with micropulse vibration device: A pilot study

Purpose

The aim of this study is to investigate the impact of vibration stimulation on gingival crevicular fluid biomarkers and orthodontic tooth movement.

Methods

Forty patients were randomly assigned to receive therapy with an intraoral vibration device (n = 20, AcceleDent®) or no treatment (n = 20) at a university orthodontic clinic. The quantity of fluid in the gingival sulcus, biomarkers of each fluid in the gingival sulcus, and orthodontic tooth movement were analyzed at three-time intervals (T1, T2, T3) before and after therapy (T0).

Results

The results showed that vibration treatment led to higher levels of osteoclast biomarkers (RNAKL, RANKL/OPG) and inflammatory biomarkers (TNF-, IL-11, IL-18) compared to the control group. Additionally, vibration treatment at T1, T2, and T3 significantly improved tooth mobility and GCF volume. The gingival crevicular fluid biomarker levels of the T0, T1, and T2 vibration groups, as well as IL-11, IL-18, TGF-1, and TNF-α vibration groups, were significantly higher than those of the control group at different time points.

Conclusion

vibration therapy was found to be closely associated with bone-breaking cells and inflammatory factor levels.

Patient-reported outcomes during accelerating the en-masse retraction of the upper anterior teeth using low-intensity electrical stimulation: a randomized controlled trial

BACKGROUND

Low-intensity electrical stimulation (LIES) is considered a relatively recent technology that has received little attention in orthodontics as a method of acceleration. This study aimed to evaluate patient-reported outcome measures when LIES is used to accelerate the en-masse retraction of the upper anterior teeth.

MATERIALS AND METHODS

The sample consisted of 40 patients (8 males, 32 females; mean age 21.1 ± 2.3 years), with Class II division I malocclusion who required extraction of the first premolars to retract upper anterior teeth. They were randomly assigned to the LIES group (n = 20) and the conventional en-masse retraction group (CER; n = 20). Patient responses regarding pain, discomfort, burning sensation, swelling, chewing difficulty, speech difficulty, and painkillers' consumption were recorded at these nine assessment times: 24 h (T1), 3 days (T2), and 7 days (T3) after force application, then in the second month after 24 h (T4), 3 days (T5), and 7 days (T6) of force re-activation, and finally after 24 h (T7), 3 days (T8), and 7 days (T9) of force re-activation in the third month.

RESULTS

The mean values of pain perception were smaller in the LIES group than those in the CER group at all assessment times with no statistically significant differences between the two groups except during the second and third months (T5, T6, T8, and T9; P < 0.005). However, discomfort mean values were greater in the LIES group with significant differences compared to CER group during the first week of the follow-up only (T1, T2, and T3; P < 0.005). Burning sensation levels were very mild in the LIES group, with significant differences between the two groups at T1 and T2 only (P < 0.001). Speech difficulty was significantly greater in the LIES group compared to CER group at all studied times (P < 0.001). High levels of satisfaction and acceptance were reported in both groups, without any significant difference.

CONCLUSION

Both the LIES-based acceleration of en-masse retraction of upper anterior teeth and the conventional retraction were accompanied by mild to moderate pain, discomfort, and chewing difficulty on the first day of retraction. These sensations gradually decreased and almost disappeared over a week after force application or re-activation.

TRIAL REGISTRATION

ClinicalTrials.gov, ClinicalTrials.gov, NCT05920525. Registered 17 June 2023 - retrospectively registered, http://clinicaltrials.gov/study/NCT05920525?term=NCT05920525&rank=1 .

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.

Accelerated Orthodontics: Stepping Into the Future Orthodontics

Orthodontic treatment signifies a transformative journey for individuals seeking not only enhanced oral health but also a boost in aesthetics and self-confidence. Nonetheless, the protracted timeline associated with conventional orthodontic care has been a persistent concern for both patients and practitioners. In this comprehensive review, we embark on an exploration of innovative strategies aimed at expediting orthodontic tooth movement (OTM). By doing so, we aspire to curtail treatment duration and mitigate potential risks, ultimately culminating in an elevated and more fulfilling patient experience. Traditionally, orthodontists heavily leaned on surgical techniques to hasten tooth movement. However, the recent landscape of orthodontics has been profoundly shaped by technological advancements and groundbreaking research findings, ushering in an era characterized by the embrace of minimally invasive approaches. These progressive methodologies encompass procedures like Piezocision, Discision, and Microosteoperforation (Alveocentesis). Beyond the obvious benefits of reduced patient discomfort, these techniques significantly truncate treatment periods, a development that addresses a primary concern of many patients. Moreover, this review delves into non-invasive alternatives, including cyclic vibrations, photobiomodulation, direct light electric current, and static or pulsed magnetic fields, as well as systemic and local administration of biological substances and hormones, all of which hold substantial promise in optimizing OTM. Furthermore, our exploration extends to a diverse spectrum of medications that have demonstrated their efficacy in expediting OTM. These encompass NSAIDs, acetaminophen, corticosteroids, bisphosphonates, herbal medicine biomaterials, and synthetic biomaterials like graphene dioxide. Every technique and medication is subjected to meticulous evaluation, taking into account its indications, contraindications, advantages, disadvantages, clinical implications, and limitations. Through this review, we endeavor to equip orthodontic professionals with a profound understanding of these innovative strategies. By doing so, we enable them to make informed decisions, tailored meticulously to meet the unique needs of each patient. In an ever-evolving field like orthodontics, staying abreast of these advancements becomes paramount, ultimately contributing to heightened treatment efficacy and enhanced patient satisfaction. The adoption of these innovative strategies not only holds the potential for improved clinical outcomes but also champions a patient-centric approach that could fundamentally reshape the landscape of orthodontic care.

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.

Effect of 125 Hz and 150 Hz vibrational frequency electric toothbrushes on the rate of orthodontic tooth movement and prostaglandin E2 levels

Objective

To evaluate the effects of an electric toothbrush with vibrational frequencies of 125 Hz and 150 Hz on the orthodontic tooth movement (OTM) rate and the production of prostaglandin E2 (PGE2).

Methods

Out of thirty patients (aged 18-25 years; 16 females and 14 males), ten patients each formed Group A and B, who used electric toothbrushes with 125 Hz and 150 Hz vibrations, respectively. The remaining ten patients (Group C) served as the control group and did not use electric toothbrushes. The rate of OTM and levels of PGE2 using microcapillary pipettes were calculated before the start of retraction (T0), on the 30th day (T1), on the 60th day (T2), and on the 90th day (T3) from the start of retraction in all the groups.

Results

There was a statistically significant difference in the mean OTM values and PGE2 levels in all three groups at different time intervals, with the maximum difference seen in Group B compared to Group A and least in Group C at T1, T2 and T3.

Conclusions

The rate of OTM and levels of PGE2 were highest in patients who used an electric toothbrush with 150 Hz mechanical vibration compared to those who used an electric toothbrush with 125 Hz mechanical vibration and least in patients who did not use an electric toothbrush. Mechanical vibration led to an increase in the PGE2 levels and accelerated the OTM.

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).

Impact of Low-Level Laser Therapy on Orthodontic Tooth Movement and Various Cytokines in Gingival Crevicular Fluid: A Split-Mouth Randomized Study

BACKGROUND AND OBJECTIVES

A few investigations have detailed the influence of low-level laser therapy (LLLT) on orthodontic tooth movement (OTM), with varying results. The objectives of this study were twofold: to assess the impact of LLLT on OTM and various cytokine levels in gingival crevicular fluid and to contrast the pain levels experienced by patients receiving orthodontic treatment with and without LLLT.

MATERIALS AND METHODS

This split-mouth randomized controlled prospective study comprised 40 patients with an average age of 19.7±2.4 years with Angle Class I malocclusion combined with bimaxillary protrusion who were advised for extraction of the maxillary first premolar and bilateral canine distalization. The control-side canine was distalized solely by the coil spring. On the test arm, a low-level gallium-aluminum-arsenide semiconductor diode laser operating at 980 nm and 100 mW with a continuous-wave energy of 8 J/cm2 was used. The canine distalization on either side was measured with a digital caliper following the first premolar extraction (TO), one month after treatment (TOTM1), two months later (TOTM2), and three months later (TOTM3). The gingival index and the level of various cytokines were determined by an enzyme-linked immunosorbent assay at the beginning of the study, on the third and seventh days, and at four, eight, and 12 weeks following the canine distalization. The intra-group and inter-group comparisons were carried out using one-way analysis of variance (ANOVA) and t-tests, respectively, at a 5% significance level.

RESULTS

The results show a highly statistically significant difference in the extent of canine distalization in the test group (TOTM1=2.92±0.44; TOTM2=1.04±0.1; TOTM3​=0.62±0.21 mm) in contrast to the control group (TOTM1=3.23±0.8; TOTM2=2.65±0.2; TOTM3​​​​=2.11±0.24 mm) (p<0.01). After three months of canine distalization, the laser and control group had 34 and 27 patients with mild gingivitis, respectively. Interleukin-1β and interleukin-6 concentrations surged with values of 0.74±0.13 and 0.049±0.001 pg/g at seven days following treatment in the laser group, respectively. The difference in tumor necrosis factor concentration between the groups was shown to be highly statistically significant in all treatment phases (p<0.001). The differences in the epidermal growth factor and microglobulin levels were found to be statistically significant within both groups from T0 to T5. The average visual analog scale (VAS) scores at several subsequent evaluations of the laser and control groups were found to be highly statistically significant.

CONCLUSION

The findings imply that when the periodontal microenvironment is stimulated by orthodontic force, several paramount cytokines are released, triggering an ordered sequence of biological processes that appear to expedite OTM with reduced associated pain.

Effect of piezoincision on the rate of mandibular molar mesialization: A randomised clinical trial

Background and Aim

The aim of this clinic study was to investigate the effect of piezoincision on the rate of mandibular molar mesialization using clinical, radiological, and biochemical methods.

Materials and Methods

Twenty-one patients requiring mandibular first molar extraction and second molar mesialization were included in the study which was designed as split-mouth study. Piezoincision was performed on the buccal surface of alveolar bone following regional alignment to the randomly selected side. 150 g of force was applied to the second molar teeth using mini-screw-supported anchorage after the piezoincision. Cone beam computed tomography (CBCT), gingival crevicular fluid (GCF) and digital model records of the patients were obtained. Two- and three-dimensional measurements were performed and compared on the CBCT images in a study which lasted 24 weeks.

Results

According to the model analysis, the canine-second molar distance was consistently reduced and a greater decrease was measured on the experimental group (p < 0.05). Second molar mesial rotations increased in both groups (p < 0.001). Two-dimensional measurements on CBCT images showed increased mesial and buccal tipping of second molars in experimental group (p < 0.001). There was a significant increase in mesialization measurements of experimental group (p < 0.001). Three-dimensional measurements on the CBCT images showed a decrease of root length in both groups (p < 0.001), and a greater decrease was found in the experimental group (p < 0.001). When intra-group changes in GCF results were examined, it was observed that there was no significant change in osteoprotegerin (OPG) values over time in experimental group (p = 0.148).

Conclusion

The piezoincision technique provided acceleration of mandibular molar mesialization and did not cause further damage to the buccal alveolar bone. Piezoincision can be used as a safe method in the mandibular molar region.

Comparative Evaluation of Effect of Micro-Osteoperforation and Mechanical Vibration on Rate of Orthodontic Tooth Movement in Young Adults With Bimaxillary Protrusion

AIM

To evaluate and compare the rate of orthodontic tooth movement and root resorption by micro-osteoperforation (MOP) and mechanical vibration in young adults with bimaxillary protrusion.

METHOD

Twenty patients having class I bimaxillary protrusion who required all first premolar extraction were allocated into two groups MOP (Group A) and mechanical vibration (Group B), with a 1:1 allocation ratio. After leveling alignment MOP was performed on either side of the arch, and vibration was applied on the contralateral side 20 mins per day. Canines were retracted with nickel-titanium coil springs, and Alginate impressions were taken every four weeks till 4 months.

RESULT

The mean rate of retraction of canines of Group A was more than Group B. There was a statistically significant difference between Group A and Group B. (p=0.0120) Conclusion: The mean rate of retraction of canines treated by MOP was 1.15 mm per 4 weeks, and by mechanical vibration, 0.8mm per 4 weeks.

Light orthodontic force with high-frequency vibration accelerates tooth movement with minimal root resorption in rats

OBJECTIVES

To determine and compare the effects of high-frequency mechanical vibration (HFV) with light force and optimal force on the tooth movement and root resorption in rat model.

MATERIALS AND METHODS

Seventy-two sites in 36 male Wistar rats were randomly assigned using a split-mouth design to control (no force/no vibration) or experimental groups: HFV (125 Hz), light force (5 g), optimal force (10 g), light force with HFV, and optimal force with HFV for 14 and 21 days. The amount of tooth movement, 3D root volume, and root resorption area were assessed by micro-computed tomography and histomorphometric analysis.

RESULTS

Adjunction of HFV with light force significantly increased the amount of tooth movement by 1.8-fold (p = 0.01) and 2.0-fold (p = 0.01) at days 14 and 21 respectively. The HFV combined with optimal force significantly increased the amount of tooth movement by 2.1-fold (p = 0.01) and 2.2-fold (p = 0.01) at days 14 and 21 respectively. The root volume in control (distobuccal root (DB): 0.60 ± 0.19 mm³, distopalatal root (DPa): 0.60 ± 0.07 mm³) and HFV (DB: 0.60 ± 0.08 mm³, DPa: 0.59 ± 0.11 mm³) were not different from the other experimental group (range from 0.44 ± 0.05 to 0.60 ± 0.1 mm³) with the lowest volume in optimal force group.

CONCLUSIONS

Adjunction of HFV with orthodontic force significantly increased tooth movement without causing root resorption.

CLINICAL RELEVANCE

Using light force with HFV could help to identify alternative treatment option to reduce the risk of root resorption.

Human Interleukin-1β Profile and Self-Reported Pain Monitoring Using Clear Aligners with or without Acceleration Techniques: A Case Report and Investigational Study

Introduction. There is a growing demand for more aesthetic, comfortable, and faster orthodontic treatments, and clear aligners emerged as a solution to fulfill this need. However, the effectiveness of clear aligners to treat complex malocclusions is yet contentious. The use of acceleration methods could improve the efficacy of clear aligners by stimulating cells' mechanobiology through numerous pathways, but this hypothesis is still poorly explored. Objective. We aimed to monitor the release profile of an inflammatory marker-the interleukin-1β-and to evaluate its relationship with self-reported pain scores with and without the use of acceleration techniques during an orthodontic treatment requiring difficult tooth movements with clear aligners. Case Report. Here, we report a case of a 46-year-old female patient who presented functional and aesthetic complaints. Intraoral examination revealed a diminished overjet and overbite, rotation of teeth 45 and 24, absence of teeth 25, 35, and 36, buccolingual dislocation of tooth 21, a tendency to a Class III malocclusion, and a 2 mm left deviation of the lower midline. This study is divided into three stimulation phases: no stimulation, mechanical vibration stimulation, and photobiomodulation. Interleukin-1β levels in gingival crevicular fluid samples from the pressure side of six selected teeth were evaluated at four time points after the orthodontic treatment onset. Pain monitoring in those teeth was performed using a visual analogue scale at the same time points. Results. Interleukin-1β protein production peaked 24 h after treatment onset. Complex movements were associated with increased self-reported pain. Conclusion. Clear aligners show limitations in solving complex tooth movements, even when combined with acceleration. The development of customized and programmable stimulation microdevices integrated into “smart aligners,” which could be designed to specifically stimulate the direction of movement and stimulation parameters and could constitute a solution to optimize the orthodontic tooth movement with clear aligners.

Effects of compressive stress combined with mechanical vibration on osteoclastogenesis in RAW 264.7 cells

OBJECTIVES

To investigate the effects of compressive force and/or mechanical vibration on NFATc1, DCSTAMP, and CTSK (cathepsin K) gene expression and the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells in RAW 264.7 cells, a murine osteoclastic-like cell line.

MATERIALS AND METHODS

RAW 264.7 cells were subjected to mechanical vibration, compressive force, or compressive force combined with vibration. Cell viability and the numbers of TRAP-positive multinucleated cells were evaluated. NFATc1, DCSTAMP, and CTSK gene expressions were analyzed using real-time quantitative reverse transcription polymerase chain reaction.

RESULTS

Compressive force combined with mechanical vibration significantly increased the numbers of TRAP-positive multinucleated cells but did not significantly affect cell viability. In addition, compressive force combined with mechanical vibration significantly increased NFATc1, DCSTAMP, and CTSK mRNA expression compared with compressive force or vibration alone.

CONCLUSIONS

Compressive force combined with mechanical vibration induces osteoclastogenesis and upregulates NFATc1, DCSTAMP, and CTSK gene expression in RAW 264.7 cells. These results provide more insight into the mechanisms by which vibratory force accelerates orthodontic tooth movement.

Effect of vibration on orthodontic tooth movement in a double blind prospective randomized controlled trial

The purpose of the present study was to investigate the effect of vibration on orthodontic tooth movement and safety assessment based on our previous basic research in animal experiments. A double-blind prospective randomized controlled trial using split-mouth design was conducted in patients with malocclusion. The left and right sides of maxillary arch were randomly assigned to vibration (TM + V) and non-vibration (TM) groups. After leveling, vibrations (5.2 ± 0.5 g-forces (gf), 102.2 ± 2.6 Hertz (Hz)) were supplementary applied to the canine retracted with 100 gf in TM + V group for 3 min at the monthly visit under double-blind fashion, and the canine on the other side without vibration was used as TM group. The amount of tooth movement was measured blindly using a constructed three-dimensional dentition model. The amount of canine movement per visit was 0.89 ± 0.55 mm in TM group (n = 23) and 1.21 ± 0.60 mm in TM + V group (n = 23), respectively. There was no significant difference of pain and discomfort, and root resorption between the two groups. This study indicates that static orthodontic force with supplementary vibration significantly accelerated tooth movement in canine retraction and reduced the number of visits without causing side effects.

Effectiveness of platelet rich fibrin versus demineralized bone xenograft in periodontally accelerated osteogenic orthodontics: A pilot comparative clinical study

OBJECTIVES

To compare the rate of extraction space closure between periodontally accelerated osteogenic orthodontics (PAOO) using platelet-rich fibrin (PRF) (Group 1) and PAOO using demineralized bone xenograft (DMBM) (Group 2) and to compare the level of wound healing between the PRF group vs the DMBM group after PAOO.

MATERIALS AND METHODS

A two-arm prospective single blind pilot study with a split-mouth design was used in which 14 patients requiring premolar extraction were divided into two groups: PRF and DMBM. En-masse space closure was carried out with using mini implants after the PAOO procedure. The amount of space closure was measured at five time points with 2-week intervals within 2 months. The gingival healing levels were assessed using early wound healing scores on the first postoperative day.

RESULTS

The rate of extraction space closure was faster in the experimental quadrant at all time points (T1-T4) in the PRF group and at time points (T3, T4) in the DMBM group. Comparison between experimental quadrants showed a significant increase in the rate of space closure in the PRF group T1 to T3 (P < .05). The PRF group showed higher total early healing scores than the DMBM group.

CONCLUSIONS

PRF, when used in the PAOO procedure, produces a faster rate of space closure with better early wound healing than DMBM.

Peak loads on teeth from a generic mouthpiece of a vibration device for accelerating tooth movement

INTRODUCTION

The effect of vibrational force (VF) on accelerating orthodontic tooth movement depends on the ability to control the level of stimulation in terms of its peak load (PL) on the tooth. The objective of this study was to investigate the PL distribution on the teeth when a commercial VF device is used.

METHODS

Finite element models of a human dentition from cone-beam computed tomography images of an anonymous subject and a commonly used commercial VF device were created. The device consists of a mouthpiece and a VF source. The maxilla and mandible bites on the mouthpiece with the VF applied to it. Interface elements were used between the teeth and the mouthpiece, allowing relative motion at the interfaces. The finite element model was validated experimentally. Static load and VF with 2 frequencies were used, and the PL distributions were calculated. The effects of mouthpiece materials and orthodontic appliances on the PL distribution were also investigated.

RESULTS

The PL distribution of this kind of analyzed device is uneven under either static force or VF. Between the anterior and posterior segments, the anterior segment receives the most stimulations. The mouthpiece material affects the PL distribution. The appliance makes the PL more concentrated on the incisors. The VF frequencies tested have a negligible influence on both PL magnitude and distribution.

CONCLUSIONS

The device analyzed delivers different levels of stimulation to the teeth in both maxilla and mandible. Changing the material property of the mouthpiece alters the PL distribution.

Impact of Vibration on the Levels of Biomarkers: A Systematic Review

Introduction:

The objective of this systematic review is to assess the effect of vibrational force on biomarkers for orthodontic tooth movement.

Methods:

An electronic search was conducted for relevant studies (up to December 31, 2020) on the following databases: Pubmed, Google scholar, Web of Science, Cochrane Library, Wiley Library, and ProQuest Dissertation Abstracts and Thesis database. Hand searching of selected orthodontic journals was also undertaken. The selected studies were assessed for the risk of bias in Cochrane collaboration risk of bias tool. The “traffic plot” and “weighted plot” risk of bias distribution are designed in the RoB 2 tool. The 2 authors extracted the data and analyzed it.

Results:

Six studies fulfilled the inclusion criteria. The risks of biases were high for 4, low and some concern for other 2 studies. The biomarkers, medium, device, frequency and duration of device, as well as other data were extracted. The outcomes of the studies were found to be heterogenous.

Conclusion:

One study showed highly statistically significant levels of IL-1 beta with <.001. Rate of tooth movement was correlated with levels of released biomarkers under the influence of vibrational force in 3 studies, but it was found to be significant only in 1 study. It was further observed that vibration does not have any significant reduction in pain and discomfort.

Evaluation of heat shock protein 70 and toll-like receptor 4 expression in gingival crevicular fluid in response to orthodontic forces

OBJECTIVES

The aim of this study was to assess the concentrations of heat shock protein 70 (HSP70) and toll-like receptor 4 (TLR4) during orthodontic tooth movement and to compare their levels with interleukin-1β (IL-1β), a well-known proinflammatory biomarker.

MATERIALS AND METHODS

This study consisted of 20 patients (8 males, 12 females; mean age 14.75 ± 2.34 years) who needed maxillary premolar extraction and segmental canine distalization. Concentrations of HSP70, TLR4, and IL-1β were examined before extraction (T1), at the 1st (T2), 4th (T3), 7th (T4), 14th (T5), and 30th (T6) days of canine retraction by enzyme-linked immunosorbent assay analysis of gingival crevicular fluid samples. Statistical analyses were performed with repeated measure ANOVA and Spearman's rank correlation coefficient analysis (p < 0.05).

RESULTS

HSP70 increased gradually from T1 to T6 and showed significant differences between T1-T6 and T2-T6 (T1:3.28 ± 0.92 ng/ml; T2:3.72 ± 0.66 ng/ml; T6:9.35 ± 2.45 ng/ml). The lowest TLR4 concentration was at T1, peaked at T3 and remained constant afterwards with significant differences between T1-T3, T1-T4, and T1-T6 (T1:0.71 ± 0.02 pg/ml; T3:1.04 ± 0.11 pg/ml; T4:0.95 ± 0.06 pg/ml; T6:1.00 ± 0.07 pg/ml). IL-1β increased from T1 to T6 with significant differences between T1-T4, T1-T5, and T1-T6 (T1:55.71 ± 5.48 pg/ml; T4:100.11 ± 16.92 pg/ml; T5:103.71 ± 23.19 pg/ml; T6:125.12 ± 22.04 pg/ml). The increase in HSP70 and TLR4 from T2-T3 showed a significant correlation (r = 0.598; p = 0.005).

CONCLUSIONS

The increased levels of HSP70, TLR4, and IL-1β show the contribution of these mediators to the inflammatory response from the early stages of orthodontic tooth movement.

CLINICAL RELEVANCE

The regulation of HSP70, TLR4, and/or IL-1β secretion during orthodontic force application could provide alterations for desired optimal tooth movement.

Monitoring Salivary Levels of Interleukin 1 Beta (IL-1β) and Vascular Endothelial Growth Factor (VEGF) for Two Years of Orthodontic Treatment: A Prospective Pilot Study

Results

A gradual increase in IL-1β and VEGF was observed at alignment, reaching significance at space closure (p = 0.002 and p = 0.025, respectively). At finishing, both IL-1β and VEGF declined, however, without reverting to baseline values (p = 0.172 and p = 0.207, respectively). Bland-Altman analysis showed the agreement between IL-1β and VEGF in terms of a systematic increase, with a higher percentage difference for VEGF.

Conclusions

The salivary levels of both IL-1β and VEGF increased following orthodontic treatment and reached their peaks during the treatment stage of space closure. This novel approach provides a hint on how and when to sample saliva during orthodontic treatment to analyse bone remodelling.

Levels of proinflammatory chemokines and advanced glycation end products in patients with type-2 diabetes mellitus undergoing fixed orthodontic treatment

OBJECTIVES

To explore the effect of diabetic status on the proinflammatory chemokine profile and levels of advanced glycation end products (AGEs) in gingival crevicular fluid (GCF) derived from patients with type 2 diabetes mellitus (T2DM) undergoing fixed orthodontic treatment.

MATERIALS AND METHODS

Two groups, nondiabetic and T2DM, were included. Their demographics, biochemical parameters including hemoglobin A1c, fasting blood glucose, body mass index, and oral hygiene status were recorded. GCF sampling was performed after 2 months of placement of stainless steel archwires and chemokines (primary outcome) were quantified using Human Magnetic Luminex multiplex assay. Secondary outcomes were assessment of clinical periodontal status, unstimulated whole saliva flow rate, and GCF flow rate.

RESULTS

Twenty participants each in the nondiabetic (mean age: 26.4 years) and T2DM (mean age: 27.2 years) groups gave consent to participate. Biochemical analysis showed significantly increased values for hemoglobin A1c (P < .001), fasting blood glucose (P < .0001), body mass index(P = .047), and unstimulated whole saliva flow rate (P = .041) for the T2DM group. Bleeding on probing was significantly higher in participants with T2DM than nondiabetic participants (P = .039). Resistin (P = .034) and AGEs (P = .017) showed significantly higher values in participants with T2DM than nondiabetic participants. Pearson correlation analysis indicated a significant positive correlation between resistin (r = 0.1372; P = .022) and AGEs (r = 0.0194; P = .0186) against bleeding on probing in participants with T2DM.

CONCLUSIONS

The biochemical profile of GCF samples from participants with T2DM after alignment demonstrated higher levels of resistin and AGEs. The data suggest the presence of a proinflammatory response in patients with T2DM undergoing fixed orthodontic treatment.

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.

Which method is more effective for accelerating canine distalization short term, low-level laser therapy or piezocision? A split-mouth study

OBJECTIVES

This study evaluated and compared the effects of low-level laser therapy (LLLT) and piezocision on the amount of orthodontic tooth movement.

MATERIALS AND METHODS

Forty maxillary canines from 20 patients (mean age, 16.35 ± 1.14 years) were evaluated in a split-mouth design study. Miniscrew-supported canine distalization was performed. Piezocision was applied in the right maxillary canine region, and the left maxillary canines were irradiated with a diode laser (940 nm, 5 J/cm²). LLLT was performed on day 0 and days 3, 7, 14, 21, and 28 after the start of canine distalization in the first 4‑week period. Data were evaluated at baseline (T0) and after 4 (T1), 8 (T2), and 12 (T3) weeks. The amount of canine movement was determined from three-dimensional models, and the angulation of canines and first molars was analyzed based on lateral cephalograms.

RESULTS

Intragroup and intergroup comparisons of canine distalization were performed for four different time intervals (T0-T1, T1-T2, T2-T3, T0-T3). The canine tooth movement in the T0-T1 period was significantly greater in the LLLT group compared to the piezocision group. No statistically significant differences were observed between the groups for the T1-T2, T2-T3, and T0-T3 periods. The amount of canine distalization in the T0-T1 period was significantly greater than that in the T1-T2 and T2-T3 periods in both groups. Tooth movement during the T1-T2 period was higher than that in the T2-T3 period in the LLLT group. Cephalometric evaluation revealed no statistically significant difference between the groups with respect to canine and first molar angulation.

CONCLUSION

Although laser application seems more effective during the first 4‑week period, considering the 12-week period, the effects of LLLT and piezocision on orthodontic tooth movement during canine distalization were similar.

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.

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.

Vibration synergistically enhances IL-1β and TNF-α in compressed human periodontal ligament cells in the frequency-dependent manner

Objectives

To investigate whether mechanical vibration at 30 or 60 Hz combined with compressive force alter IL-1β and TNF-α expression in human periodontal ligament (hPDL) cells.

Methods

hPDL cells isolated from the roots of first premolar teeth extracted from four independent donors were cultured and exposed to vibration (0.3 g, 20 min per cycle, every 24 h for 3 cycles) at 30 or 60 Hz (V30 or V60), 2.0 g/cm² compressive force for 2 days (CF), or a combination of compressive force and vibration at 30 Hz or 60 Hz (V30CF or V60CF). Quantitative real-time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assays (ELISAs) were used to determine IL-1β and TNF-α mRNA and protein, respectively.

Results

The levels of IL-1β and TNF-α did not alter in groups V30 and V60. While, they were upregulated in groups CF, V30CF and V60CF. In addition, IL-1β mRNA and TNF-α mRNA and protein were expressed at significantly higher levels in group V30CF compared to CF group. However, IL-1β protein levels between V30CF and CF groups did not reach statistical significance.

Conclusions

30 Hz vibration had the synergistic effects with compressive force on the upregulation of IL-1β mRNA and TNF-α mRNA and protein in PDL cells, while 60 Hz vibration did not have this synergistic effect.

Influence of a Lubricating Gel (Orthospeed®) on Pain and Oral Health-Related Quality of Life in Orthodontic Patients during Initial Therapy with Conventional and Low-Friction Brackets: A Prospective Randomized Clinical Trial

The aim of this study was to investigate whether statistically significant differences exist regarding pain and the impact on oral quality of life of orthodontic treatment. A conventional brackets system was compared with low-friction brackets. A total of 90 patients (male = 35, female = 55) were chosen for this randomized clinical trial. Pain was assessed at 4, 8, and 24 hours and 2, 3, 4, 5, 6, and 7 days after the start of treatment using the McGill Pain Questionnaire. Oral health-related quality of life (OHRQoL) was assessed using the Oral Health Impact Profile-14 (OHIP-14) questionnaire. Oral quality of life was assessed at one month, with patients with low-friction brackets describing lower levels of pain. The patients with conventional brackets indicated a worse impact on their quality of life compared to the group with low-friction brackets. Statistically significant differences were found between the groups, with maximum pain observed between the first 24 and 48 hours, and the values of minimum pain are reached after 7 days. The pain and impact on oral quality of life was statistically worse in patients with conventional brackets compared to patients with low-friction brackets. The type of bracket system used was therefore shown to influence patients' perceptions of pain and impact on their OHRQoL.

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.

Vibration activates the actin/NF-κB axis and upregulates IL-6 and IL-8 expression in human periodontal ligament cells

We previously reported that mechanical vibration-induced proinflammatory cytokines, interleukin-6 (IL-6) and IL-8, expression in human periodontal ligament (hPDL) cells, however, the underlying mechanism remained unclear. Mechanical stimuli are able to activate cellular responses by inducing the activation of several signaling pathways including cytoskeletal changes and inflammation. The actin cytoskeleton is a highly dynamic network and plays many important roles in intracellular events. Here, we aimed to investigate the involvement of a pivotal mediator of inflammatory responses, nuclear factor-κB (NF-κB), and actin polymerization in vibration-induced upregulation of IL-6 and IL-8 expression in hPDL cells. hPDL cells were pretreated with the NF-κB inhibitor BAY 11-7082 or cytochalasin D, respectively, before exposure to vibration. IL-6 and IL-8 messenger RNA (mRNA) and protein expression were quantified by quantitative polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Subcellular localization of the NF-κB p65 subunit was visualized by immunofluorescent staining. We found an increase in NF-κB nuclear translocation in vibrated cells compared with control cells. Pretreatment with BAY 11-7082 significantly inhibited vibration-induced IL-6 and IL-8 mRNA and protein expression in hPDL cells. Moreover, pretreatment with cytochalasin D inhibited NF-κB nuclear translocation and attenuated upregulation of IL-6 and IL-8 mRNA and protein in vibrated cells. Therefore, modulation of actin cytoskeletal polymerization in response to vibration may activate the NF-κB signaling pathway and subsequently upregulate IL-6 and IL-8 expression in hPDL cells.

Mandible and iliac osteoblasts exhibit different Wnt signaling responses to LMHF vibration

Objective

The jaw bones and long bones have distinct developmental origins and respond differently to mechanical stimuli. This study aimed to compare the Wnt signaling responses of human mandible osteoblasts and long bone osteoblasts to low-magnitude, high-frequency (LMHF) mechanical vibration in vitro.

Methods

Primary human osteoblast cultures were prepared from mandibular bone (n = 3) and iliac bone (n = 3) specimens (six individuals). Osteoblast cell lines were subjected to vibration (0, 30, 60, 90, or 120 Hz) for 30 min. After 24 h, cells were vibrated for 30 min again, then harvested immediately to quantify Wnt10b, Wnt5a and runt-related transcription factor 2 (RUNX2) mRNA expression, β-catenin protein expression and alkaline phosphatase (ALP) activity.

Results

Mandible and iliac osteoblasts responded differently to LMHF vibration: Wnt10b mRNA was upregulated by the frequency range tested; Wnt5a, β-catenin protein expression and RUNX2 mRNA expression were not altered. Furthermore, vibration upregulated ALP activity in mandible osteoblasts, but not in iliac osteoblasts.

Conclusions

This study demonstrates mandible osteoblasts and long bone osteoblasts respond differently to LMHF mechanical vibration in terms of Wnt signaling expression and ALP activity. Therefore, the effects of whole-body vibration on the long bones cannot be generalized to the jaw bones. Furthermore, osteoblast-like cells mediate the cellular responses to vibration, at least in part, by secreting extracellular signaling molecules.

Assessment of salivary interleukin-1β (IL-1β), prostaglandin E2 (PGE2) levels and pain intensity in children and adults during initial orthodontic treatment

OBJECTIVES

To investigate pain intensity, interleukin-1β and prostaglandin E₂ values in saliva during initial orthodontic treatment among varying age groups and their correlation between these mediators.

MATERIALS AND METHODS

Twenty healthy patients distributed equally in age and gender groups were chosen. Unstimulated saliva was collected before the placement of orthodontic fixed appliance (T₀), 1 hour after the placement of the appliance with 0.014" nickel titanium archwire (T₁), 1 month after the first visit (T₂), and 1 hour after the placement of 0.016" nickel titanium archwire (T₃). The saliva samples were then analyzed for prostaglandin E₂ and interleukin-1β using enzyme-linked immunosorbent assay. Pain intensity was measured using a numerical rating scale.

RESULTS

Prostaglandin E₂ and interleukin-1β levels had increased at T₁ followed by a drop at T₂ and a subsequent increase at T₃. The prostaglandin E₂ and interleukin-1β levels were higher in adults than children. There was an insignificant correlation between the interleukin-1β and prostaglandin E₂ changes in all the patients. No significant differences were seen in pain scores between adults and children. Insignificant correlation was seen between pain scores and prostaglandin E₂ and interleukin-1β.

CONCLUSION

Prostaglandin E₂ and interleukin-1β can be detected in saliva and are increased in during the initial orthodontic treatment but are higher in adults than children. Pain intensity was not significantly different between adults and children.

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.

Effect of high-frequency vibration on orthodontic tooth movement and bone density

OBJECTIVES:

Previous reports have shown that high-frequency vibration can increase bone remodeling and accelerate tooth movement. The aim of this study was to evaluate the effects of high-frequency vibration on treatment phase tooth movement, and post-treatment bone density at initiation of retention, with cone-beam computed tomography (CBCT).

MATERIALS AND METHODS:

Thirty patients with initial Class I skeletal relationships, initial minimum-moderate crowding (3–5 mm), treated to completion with clear aligners and adjunctive high-frequency vibration, (HFV group) or no vibration, (Control group) were evaluated. The patients were instructed to change aligners as soon as they become loose. Changes in bone density associated with orthodontic treatment were evaluated using i-CAT cone-beam computed tomography (CBCT) and InVivo Anatomage^® software to quantify density using Hounsfield units (HU) between treated teeth in 10 different regions. HU values were averaged and compared against baseline (T1) and between the groups at initiation of retention (T2).

RESULTS:

The average time for aligner change was 5.2 days in the HFV group, and 8.7 days in the control group (P = 0.0001). There was significant T1 to T2 increase of HU values in the upper arch (P = 0.0001) and the lower arch (P = 0.008) in the HFV group. There was no significant change in average HU values in the upper (P = 0.83) or lower arches (P = 0.33) in the control group. The intergroup comparison revealed a significant difference in the upper, (P = 0.0001) and lower arches (P = 0.007).

CONCLUSION:

High-frequency vibration adjunctive to clear aligners, allowed early aligner changes that led to shorter treatment time in minimum-moderate crowded cases. At initiation of retention, the HFV group demonstrated statistically significant increase as compared with pre-treatment bone density, whereas control subjects showed no significant change from pre-treatment bone density.

Low magnitude high frequency vibration induces RANKL via cyclooxygenase pathway in human periodontal ligament cells in vitro

Objective

This study aimed to examine the effects of PGE2 on RANKL expression in response to vibration and vibration in combination with compressive stress and characterise this transduction pathway in periodontal ligament (PDL) cells.

Methods

Cultured human PDL cells obtained from extracted premolar teeth (from six individuals) were subjected to three cycles of vibration (0.3 g, 30 Hz for 20 min every 24 h; V), compressive stress (1.5 g/cm², 48 h; C) or vibration in combination with compressive stress (VC). To investigate whether the expression of RANKL and PGE2 was COX-dependent, PDL cells were treated with indomethacin prior to the onset of mechanical stimulation. RANKL and OPG expressions were examined by quantitative real-time polymerase chain reaction (qPCR). Quantification of PGE2, soluble RANKL (sRANKL) and OPG productions were measured using enzyme-linked immunosorbent assay (ELISAs).

Results

All mechanical stresses (V, C and VC) significantly increased PGE2 and RANKL. OPG was not affected by vibration, but was downregulated in compressed cells (C and VC). Indomethacin abolished induction of RANKL and downregulated OPG in response to all mechanical stresses.

Conclusion

These results suggest that vibration, compressive stress and vibration in combination with compressive stress induce RANKL expression in human PDL cells by activating the cyclooxygenase pathway.

Effectiveness of electric toothbrush as vibration method on orthodontic tooth movement: a split-mouth study

Objective:

To investigate the effects of application of vibratory stimuli, using an electric toothbrush, on the rate of orthodontic tooth movement during maxillary canine retraction.

Methods:

A split-mouth study was conducted in 28 subjects (mean age = 20.8 years; ranging from 18 to 24 years) whose bilateral maxillary first premolars were extracted with subsequent canine retraction. On the Vibration side, light force (100 g) was applied to the canine for 90 days, in combination with vibratory stimuli provided by an electric toothbrush; only orthodontic force was applied to the canine on the non-vibration side. Amount of canine movement was measured monthly. Related to electronic toothbrush usage, a diary was provided to each patient for recording discomfort during experimental period, having 100-mm visual analogue scale (VAS). The paired t-test was used to assess the differences in amount of tooth movement between canines of the vibration and non-vibration sides.

Results:

The amount of tooth movement was similar for canines on the vibration side and on the non-vibration side (mean 0.81 ± 0.10 mm and 0.82 ± 0.11 mm, respectively, p> 0.05). Plaque accumulation was minimal in any subject throughout the study. No subject reported discomfort as a result of using the electric toothbrush.

Conclusions:

This study demonstrates that application of vibratory stimuli using an electric toothbrush, in combination with light orthodontic force, do not accelerate 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.

Effects of low magnitude high frequency mechanical vibration combined with compressive force on human periodontal ligament cells in vitro

Objective

Vibration can be used to accelerate tooth movement, though the exact mechanisms remain unclear. This study aimed to investigate the effects of low magnitude high frequency (LMHF) vibration combined with compressive force on periodontal ligament (PDL) cells in vitro.

Materials and methods

Human PDL cells were isolated from extracted premolar teeth of four individuals. To determine the optimal frequency for later used in combination with compressive force, three cycles of low-magnitude (0.3 g) vibrations at various frequencies (30, 60, or 90 Hz) were applied to PDL cells for 20 min every 24 h. To investigate the effects of vibration combined with compressive force, PDL cells were subjected to three cycles of optimal vibration frequency (V) or 1.5 g/cm2 compressive force for 48 h (C) or vibration combined with compressive force (VC). Cell viability was assessed using MTT assay. PGE2, soluble RANKL (sRANKL), and OPG production were quantified by ELISA. RANKL, OPG, and Runx2 expression were determined using real-time PCR.

Results

Cell viability was decreased in groups C and VC. PGE2 and RANKL, but not OPG, were increased in groups V, C, and VC, thus increasing the RANKL/OPG ratio. The highest level was observed in group VC. sRANKL was increased in groups V, C, and VC; however, no significant different between the experimental groups. Runx2 expression was reduced in groups C and VC.

Conclusions

Vibration increased PGE2, RANKL, and sRANKL, but not OPG and Runx2. Vibration had the additive effects on PGE2 and RANKL, but not sRANKL in compressed PDL cells.

[Bone mechanobiology, an emerging field: a review]

INTRODUCTION

Mechanobiology, at the interface between biology and biophysics, studies the impact of mechanical forces on tissues, cells and biomolecules. The application of orthodontic forces, followed by induced tooth displacement, is a striking example of its clinical application.

OBJECTIVE

The purpose of this article was to compile a review of the literature on the subject of mechanobiology; from its detection at bone level to the presentation of stimulated intracellular pathways.

MATERIALS AND METHODS

The literature search was conducted on the Pubmed database in April 2018, with associations of the terms "mechanobiology", "orthodontics", "cell culture", "physiopathology".

RESULTS

Three major areas of research were selected: highlighting of the phenomenon and its application in the field of bone biology; the cellular effectors of mechanobiology and its clinical applications. The use of mechanobiology in dentofacial orthopedics opens up a new field of reflection for clinicians regarding future advances in orthodontics.

Effect of the application of high-frequency mechanical vibration on tooth length concurrent with orthodontic treatment using clear aligners: A retrospective study

OBJECTIVES:

To evaluate the possible change in teeth lengths as an indicator of orthodontically induced tooth root resorption (OITRR) after high-frequency mechanical vibration (HFV) treatment concurrent with Invisalign Smart Track® aligners as evaluated by cone beam computed tomography (CBCT).

MATERIALS AND METHODS:

The sample, composed of 30 patients with an average age of 26 ± 11 years and Class I malocclusion with an initial anterior crowding ranging from 3 to 5 mm, was divided equally into two groups; Group I received adjunctive high-frequency mechanical vibration (HFV); Group II, the control, did not receive adjunctive mechanical treatment. The maxillary incisor's teeth lengths were measured using Mimics software before (T1) and after (T2) treatment. All data were analyzed using Student's t-test. Reliability testing was completed by randomly selecting 10 patients’ CBCTs, and their teeth lengths were measured twice by the same investigator over a 15-day interval and compared confirming intra-operator accuracy.

RESULTS:

The control group showed a statistically significant decrease in tooth lengths compared to the HFV group which showed nonstatistically significant change of tooth lengths.

CONCLUSION:

Patients treated with HFV showed minimum tooth length changes after treatment, which may indicate that HFV can reduce OITRR with treatment using clear aligners.

The effect of compressive force combined with mechanical vibration on human alveolar bone osteoblasts

Objective

This study aimed to investigate the effects of compressive force combined with mechanical vibration on the expression of pro-inflammatory cytokines that promote osteoclastogenesis and related to orthodontic tooth movement acceleration in human alveolar bone osteoblasts in vitro.

Methods

Osteoblasts were subjected to compressive force (C), mechanical vibration (V), compressive force combined with mechanical vibration (CV), or no force as a control for 12, 24 and 48 h. Interleukin-1 beta (IL-1β), interleukin-6 (IL-6), receptor activator of nuclear factor kappa-Β ligand (RANKL) and osteoprotegerin (OPG) mRNA and protein expression were assessed using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assays.

Results

In C and CV groups, IL-1β and IL-6 mRNA and protein expression were significantly higher and OPG mRNA and protein expression were significantly lower than control and V groups. However, the expressions were not different between C and CV groups. RANKL mRNA and protein expression were not different between any groups. While, OPG mRNA and protein expression in V group were significantly higher than control group.

Conclusions

Vibration neither enhanced nor inhibited the expression of IL-1β, IL-6, RANKL and OPG in compressed human alveolar bone osteoblasts.

Low-level laser therapy increases interleukin-1β in gingival crevicular fluid and enhances the rate of orthodontic tooth movement

INTRODUCTION

The aim of this investigation was to evaluate the effects of low-level laser therapy on interleukin-1β (IL-1β) levels in gingival crevicular fluid and its correlation with orthodontic tooth movement.

METHODS

A split-mouth design was used in 10 subjects (6 female, 4 male) aged 14 to 25 years, whose maxillary first premolars were extracted. A gallium-aluminum-arsenide semiconductor diode laser (wavelength, 940 nm; energy density, 8 J/cm2; power output, 100 mW) delivered low-level laser therapy to the experimental canine undergoing distalization at 10 points. The control canine was distalized without low-level laser therapy. The experimental and control canines were distalized using a force of 150 g provided by nickel-titanium closed-coil springs. Gingival crevicular fluid was collected at 5 time points from the control and experimental sides, and the levels of IL-1β were analyzed by enzyme-linked immuno-sorbent assay (ELISA). The distal movements of the maxillary canines were measured and compared.

RESULTS

Increased levels of IL-1β were observed in the experimental canines compared with the control canines (P <0.001). Cumulative tooth movements over an 8-week experimental period were greater for the experimental canines (occlusogram and software, 4.450 and 4.4903 mm, respectively) compared with the control canines (occlusogram and software, 2.025 and 2.0501 mm, respectively). A positive correlation existed between the IL-1β levels and the amounts of tooth movement across all time intervals.

CONCLUSIONS

In combination with light orthodontic force, application of low-level laser therapy increased the levels of IL-1β in gingival crevicular fluid and accelerated orthodontic tooth movement.

Vibration enhances PGE2 , IL-6, and IL-8 expression in compressed hPDL cells via cyclooxygenase pathway

BACKGROUND

Although vibration combined with orthodontic force may accelerate orthodontic tooth movement, little is known about the mechanisms that regulate the associated cellular responses. The goal of this study was to investigate whether mechanical vibration combined with compressive force regulates cyclooxygenase (COX)-2/prostaglandin E2 (PGE₂ ) and interleukin (IL)-6 and IL-8 messenger RNA (mRNA) and protein expression in human periodontal ligament (hPDL) cells via the COX pathway.

METHODS

The primary cultured hPDL cells were exposed to mechanical vibration, compressive force or a combination of both mechanical vibration and compressive force at 24, 48, and 72 hours. The COX-2, IL-6, IL-8, receptor activator of nuclear factor kappa-Β ligand (RANKL), and osteoprotegrin (OPG) mRNA expressions were determined using quantitative real-time polymerase chain reaction (qPCR). The PGE₂ , IL-6, and IL-8 protein expressions were quantified by enzyme-linked immunosorbent assay (ELISA). To demonstrate whether the expression of PGE₂ , IL-6, and IL-8 was in the COX-dependent pathway, the hPDL cells were treated with indomethacin. To determine whether PGE₂ stimulated the hPDL cells to express IL-6 and IL-8, exogenous PGE₂ was added to the culture media.

RESULTS

The combination of mechanical vibration and compressive force synergistically upregulated RANKL/OPG, COX-2/PGE₂ , IL-6 and IL-8 mRNA, and protein expression. The indomethacin significantly attenuated the increases of PGE₂ , IL-6, and IL-8 expression in cells stimulated with compressive force or mechanical vibration combined with compressive force. In addition, exogenous PGE₂ increased IL-6 and IL-8 mRNA and protein expressions in hPDL cells.

CONCLUSION

Mechanical vibration may enhance alveolar bone resorption at the compression side during orthodontic tooth movement via a mechanism involving the cyclooxygenase pathway.

Effects of High Frequency Acceleration Device on Aligner Treatment-A Pilot Study

Evaluation of the effect of a high frequency acceleration device (HFA) on clear aligner exchange intervals and treatment time required to achieve prescribed tooth movements. Sixteen subjects with similar Class I malocclusions, ≤5 mm crowding, and treated with aligner orthodontic therapy (Invisalign) were divided into two groups. Group 1 (experimental; n = 8) underwent aligner treatment in conjunction with daily use of the HFA device and exchanged aligners every five days. Group 2 (controls; n = 8) underwent aligner treatment without use of the device and exchanged aligners every 14 days according to the manufacturer’s recommended interval. All subjects were treated by one investigator, and results—total number of aligners used, and number of refinements required—were evaluated by both prior to final mobile retention (Vivera) scan. A significant decrease in both treatment time and number of aligners required to complete treatment was observed by HFA subjects vs. controls. In addition, no refinements were required by HFA subjects, whereas six of eight control subjects required one or more refinements. The results of the present preliminary report showed that the use of the HFA device in conjunction with aligner orthodontic treatment resulted in a significant decrease in the length of treatment. Moreover, the number of patients requiring refining treatment was significantly lower.

Iliac and mandible osteoblasts exhibit varied responses to LMHF vibration

The facial and long bones have distinct developmental origins, structures, and cellular compositions. This study aimed to compare the in vitro responses of human mandible and long bone osteoblasts to low-magnitude, high-frequency (LMHF) mechanical vibration in terms of expression of mediators of bone remodeling. Osteoblast-like cell cultures were prepared from iliac crest and mandibular bone specimens from three individuals and cultured in osteogenic induction media. Induction of mature osteoblastic phenotypes was confirmed by analysis of DNA content, alkaline phosphatase activity and gene expression every 3 days for 27 days. Based on gene expression, mature osteoblasts formed by day 15 of induction culture. After 15 days of culture in induction media, mature osteoblasts were subjected to vibration (0, 30, or 60 Hz) for 30 min every 24 h. After 48 h, RANKL, OPG, IL-1β, IL-6 and TGF-β gene, and protein expression were determined by real-time PCR analysis of total cellular mRNA and ELISAs of the cell supernatants. Both iliac and mandible osteoblasts responded to LMHF vibration: IL-1β and RANKL mRNA were downregulated and IL-6 mRNA was upregulated. However, TGF- β mRNA was unaltered and OPG mRNA was upregulated in iliac osteoblasts, whereas both TGF-β and OPG mRNA were downregulated in mandible osteoblasts. As a result, LMHF reduced the RANKL/OPG mRNA ratio in iliac osteoblasts but did not alter the RANKL/OPG mRNA ratio in mandible osteoblasts. This study suggests mature iliac osteoblasts exhibit a more potent anti-resorptive response to vibration, while this tendency was not obviously apparent in mature mandible osteoblasts.