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

miR-223-3p Mitigates Mitochondrial Dysfunction and Cementoblast Apoptosis in Orthodontic Root Resorption via FoxO3

AIM

The aim of this study was to elucidate the roles of miR-223-3p in orthodontically induced inflammatory root resorption (OIIRR).

METHODS

We used high-throughput miRNA sequencing and transcriptome sequencing to analyze the differentially expressed miRNAs and mRNAs in OCCM-30 cells under hypoxia. Real-time quantitative PCR (RT-qPCR) and Western blotting were used to assess the expression of genes and proteins related to apoptosis, oxidative stress, and mitochondrial dysfunction. Fluorescence staining was employed to detect changes in cellular ROS (reactive oxygen species), MMP (mitochondrial membrane potential), and mtROS (mitochondrial ROS) expression.

RESULTS

We found that miR-223-3p targeted FoxO3 to regulate apoptosis in cementoblasts under hypoxic conditions. Moreover, hypoxia-induced FoxO3 increased oxidative stress and induced mitochondrial dysfunction in cementoblasts, resulting in cell apoptosis. Administration of the ROS inhibitor NAC (N-acetyl cysteine) effectively reversed FoxO3-induced oxidative stress and mitochondrial dysfunction, thereby rescuing cell apoptosis.

CONCLUSIONS

miR-223-3p targets FoxO3 and regulates the apoptosis of cementoblasts by improving oxidative stress and mitochondrial dysfunction. These findings may offer new insights into the mechanism of OIIRR.

Adjunctive therapies in orthodontics: a scoping systematic review

BACKGROUND

Orthodontic tooth movement (OTM) induces physiological and sometimes pathological inflammation in periodontal tissues. This review evaluates the effectiveness of low-level laser therapy (LLLT), vibrational therapy, and probiotics as adjunctive treatments for managing inflammation, pain, and the duration of OTM.

METHODS

Medline via OVID, Cochrane, EMBASE, and Web of Science databases were utilized to identify randomized controlled trials (RCTs) published between January 1990 and November 2023. Studies were selected based on their evaluation of LLLT, vibrational therapy, and probiotics as adjuncts in fixed orthodontic treatment.

RESULTS

LLLT shows promise in enhancing orthodontic tooth movement by accelerating tooth movement and potentially reducing pain. However, disparate study outcomes indicate a need for standardized application protocols. The efficacy of vibrational therapy as an adjunct in OTM remains inconclusive. Some studies in this regard indicate a significant acceleration in OTM but most did not. Probiotic therapy shows potential to improve oral microbiota balance and inflammation but requires more rigorous studies to determine its efficacy and optimal administration methods.

CONCLUSION

Future research should focus on establishing standardized guidelines and protocols to achieve consistent and reliable outcomes across these adjunctive therapies.

The effect of micro-osteoperforation (MOP) in molar distalization treatments: an exploratory systematic review and meta-analysis of RCTs

OBJECTIVE

Molar distalization is a therapeutic approach commonly used for treating Class II malocclusions. However, the extended duration of this treatment often leads to its replacement with alternative methods that offer shorter treatment times. Micro-osteoperforation (MOP) has been introduced as a technique aimed at accelerating tooth movement and reducing treatment duration. The purpose of this study is to evaluate the impact of MOP on molar distalization outcomes to provide evidence for its effective and safe use.

SEARCH METHODS

A comprehensive search was conducted across multiple databases, including MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL, up to April 2024, without any language or date restrictions.

SELECTION CRITERIA

Only randomized clinical trials (RCTs) that addressed the defined PICO question were included in the analysis. The risk of bias in the included studies was assessed using the Cochrane Risk of Bias 2.0 (RoB 2) tool.

DATA COLLECTION AND ANALYSIS

Relevant data were extracted using custom-designed forms, and a random-effects inverse variance meta-analysis was performed to synthesize the results. The primary outcomes analyzed were the rate and amount of molar distalization, while secondary outcomes included pain levels, root resorption, and periodontal health.

RESULTS

Four RCTs, involving a total of 71 participants, were included in this exploratory review. Most studies were at low or some concerns risk of bias. The meta-analysis revealed no significant differences in the rate or amount of molar distalization between the MOP and control groups (mean difference [MD] = 0.1 mm/month and 0.01 mm, respectively, P > .05). However, the MOP group reported significantly higher pain levels on the day of the procedure (MD = 2, P = .01) on a 10-point visual analog scale (VAS) compared to the control group. This difference in pain perception was no longer significant seven days after the procedure (MD = 0.52, P = .52).

CONCLUSION

While MOP is associated with increased immediate postoperative pain, it does not significantly enhance the efficiency of molar distalization. Therefore, the use of MOP for distalization should be judiciously considered and reserved for cases that involve particularly challenging or prolonged movements, based on the specific needs and characteristics of each patient. Limitations of this review include the small number of available RCTs and variability in MOP protocols, which may limit the generalizability of the findings.

REGISTRATION

The protocol for this systematic review was registered at PROSPERO with the ID CRD42024589482.

Risk factors contributing to interproximal contact loss between an implant crown and a natural tooth

PURPOSE

Interproximal contact loss (ICL) is considered a prevalent complication for a tooth abutting an implant restoration. While numerous potential causes for ICL have been presented, there is no consensus. A review of the current literature with a focus on possible risk factors was performed.

MATERIALS AND METHODS

A PubMed search using keywords "implant OR dental implants OR implant supported prosthesis AND proximal contact loss OR ICL OR loss of interproximal contact OR open contact OR interproximal open contact OR adjacent natural teeth" resulted in 81 citations, 9 of which were relevant to the focus question. Additional references were culled from the reference lists in the identified articles. Systematic reviews, case series, and case reports were reviewed with a focus on causation, association, or correlation.

RESULTS

Eight systematic reviews and 14 case series were reviewed. The prevalence of ICL has been reported to be as low as 16% and as high as 66%. ICL was more common on the mesial side of implants and when a tooth abuts a splinted implant restoration. The absence of a uniform definition to accurately describe an interproximal (IP) contact and an open IP contact is demonstrated in the literature. A lack of standardized measurement strategies that relate to a needed consensus definition further exacerbates the broad range of reported results regarding ICL. The lack of controls for almost all the ICL literature makes it difficult to draw conclusions and comparisons to unrestored, natural tooth IP contacts and the prevalence of ICL in this patient population. As a result, the available studies are inadequate to support a causal theory and the potential risk factors associated with ICL.

CONCLUSIONS

There is a large range of reported prevalence for IP contact loss. ICL is more common when a natural tooth abuts a splinted implant restoration. ICL is more common on the mesial, as opposed to the distal, of an implant retained restoration. Consensus in the definition and measurement strategies for ICL needs to be established to provide standardized terminology and methodology. Potential risk factors such as occlusion, restorative material, and tooth contact area need to be investigated.

Effects of Vibration on Accelerating Orthodontic Tooth Movement in Clinical and In Vivo Studies: A Systematic Review

This systematic review aims to assess the impact of high (>30 Hz) and low (≤30 Hz) frequency vibrations on orthodontic tooth movement (OTM). Several articles were collected through a systematic search in the databases MEDLINE and SCOPUS, following PRISMA methodology and using a PICO question. Relevant information on selected articles was extracted, and the quality of each study was assessed by the quality assessment tools EPHPP, ROBINS-1 and STAIR. Out of 350 articles, 30 were chosen. Low-frequency vibrations did not seem to accelerate OTM with aligners or fixed appliances, despite some positive outcomes in certain studies. Conversely, high-frequency vibrations were linked to increased aligner change, tooth movement, and space closure with fixed appliances. In vivo studies reported favourable results with high-frequency vibrations (60 Hz to 120 Hz), which stimulate bone biomarkers, facilitating alveolar bone remodelling. The results suggest that high-frequency vibration effectively speeds up orthodontic tooth movement, showing promise in both in vivo and clinical studies. Larger-scale research is needed to strengthen its potential in orthodontics.

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.

Orthodontics social media, perceptions of science- and non-science-based posts among orthodontists, dentists, students and laypeople

Worldwide, social media is gaining popularity year after year. In Brazil, by 2027, there will be more than 188 million users of social media sites, against 165 million in 2022, therefore, the usage of general population and health care professionals, including orthodontists, is increasing. Differently from scientific journals that undergo a rigorous peer review process prior to publication, the same level of demand is not found on social media. Hence, this study aimed to assess whether orthodontists can recognize scientifically based and non-science-based posts and if their perceptions are different from general opinion (laypeople), dentistry students, and dentists (non-orthodontists). The posts were created using the search tool on Instagram with the hashtags #clearaligners #acceledent #selfligatingbraces and #propelorthodontics, four scientific based posts and four without or with low scientific evidence were selected and evaluated through a virtual questionnaire in the QUALTRICS platform by 385 people, (175 laypeople, 102 dentists, 58 dentistry students, and 50 orthodontists) using a visual analogue scale (VAS). In addition, four questions were asked. ANOVA (Adjusted Bonferroni correction) and Pearson's chi-squared, and Student T tests were applied to identify statistical differences. Significant difference was found only for posts with no scientific evidence between orthodontist's group when comparing with laypeople (p < 0.001) for the #selfligatingbraces, and the #propelorthodontics for the group orthodontists when compared with laypeople (p = 0.031) and dentists (p = 0.033). Instagram was the favorite social media where most of the participants spend more than 3 h. Of the participants, 97% used social media to keep informed and read the news. Almost half of the respondents search for orthodontics services on social media. Orthodontists were able to perceive differences in only two posts from the general perception (laypeople) regarding non- or low-scientific-evidence posts.

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.

The effect of micro-osteoperforation on root resorption, pulp vitality, and biological changes of teeth subjected to orthodontic tooth movement: A systematic review study

Background

These days minimally invasive micro-osteoperforation (MOPs) has accelerated orthodontic tooth movement (OTM). However, there are some conflicting reports about their various impacts; hence, the present systematic review study aimed to evaluate the effect of MOP on root resorption, pulp vitality, and the biological changes of teeth subjected to OTM.

Materials and Methods

Search in electronic databases of English literature including PubMed, Scopus, Web of sciences, Cochrane, and Google scholar as well as a manual search was performed from 2013 to 2022. Most of the studies included in this article were randomized controlled trials.

Results

From the total number of 321 found articles, 31 duplicated and 268 irrelevant articles were excluded regarding the defined inclusion and exclusion criteria. Consequently, 22 articles were subjected to the quality assessment process, and finally, 18 articles were selected for the review phase. Root resorption during tooth movement using the MOP approach was reported only in one study. Besides, except for two animal studies, all of the relevant included articles showed that MOPs significantly increased the expression of some inflammatory biomarkers known to recruit osteoclast precursors and increase the number of osteoclast cells. On the other hand, two animal studies showed no differences in osteoclast counts by using MOPs in comparison to their control groups, which was consequently the result of biologic variability between animal and human and also probably the small sample sizes of these two studies.

Conclusion

In this systematic review, according to the adverse effects of MOP on root resorption, one study showed higher levels of root resorption among patients undergoing MOP. However, this outcome was due to the different methods used to evaluate the effect of MOPs on root resorption. Moreover, a high certainty of evidence supports that MOP causes biological changes and an elevation in cytokines, chemokines, and other biomarkers that stimulates osteoclasts differentiation which in turn accelerate OTM. There was no change in pulp vitality status based on available evidence.

A different method to accelerate orthodontic tooth movement: Randomized controlled trial

Background/Aim: Since both patients and orthodontists want orthodontic treatment to be completed in a short time, various methods have been developed to accelerate orthodontic tooth movement. Vibration applications and interrupted force are noninvasive applications that are easily accepted by the patient. Aim of this study is researching modified interrupted force and vibration together how effect orthodontic tooth movement rate and pain perception that occurs during canine distalization. Material and Methods: Twenty patients (10 males and 10 females) with Class II div 1 malocclusion were selected for this study. The Hycon device on the right side activated by routine protocol, but on the left side activation protocol modified. The patients were randomly divided into 2 groups and one group was applied vibration with AcceleDent device. Each patient was provided with a chart to score the pain they experienced during canine distalization. Results: Fastest tooth movement was measured in the modified protocol(HL)+AcceleDent group (1.44 mm/monthly). The results showed that the orthodontic tooth movement in the groups which AcceleDent device used was faster than the Hycon groups only. Faster movement was observed in the left canines which Hycon device activated by modified protocol compared to right canines. These differences between groups were found statistically significant. Pain over time exhibited similar patterns in all groups. Conclusions: Using modified interrupted force protocol gave more rapid extraction space closure. The application of vibration, as an adjunct to treatment with a fixed orthodontic appliance, significantly increases the rate of orthodontic tooth movement. Vibrational force and modified activation protocol do not have significant effect on pain perception.

Comparison of the effectiveness of piezocision and microosteoperforation in leveling mandibular anterior teeth

INTRODUCTION

The primary aim of this study was to evaluate the effectiveness of piezocision and microosteoperforation (MOP) in accelerating the leveling of mandibular anterior teeth. The secondary aim was to evaluate the changes in periodontal parameters and the differences in patient comfort.

METHODS

Forty-five patients in the study were randomly divided into 3 groups. After bonding mandibular teeth, the patients in the first group (9 girls, 6 boys) underwent piezocision, and the patients in the second group (10 girls, 5 boys) underwent MOP. Patients in the third group (7 girls, 8 boys) comprised the control group. The patients were asked to complete a visual analog scale for pain assessment during the first week of treatment and to complete the Oral Health Impact Profile-14 questionnaire at the end of the week. Little's irregularity index was measured from plaster models taken at the start of the mandibular bonding process, 4 weeks, 8 weeks, 12 weeks, and 16 weeks after the mandibular bonding process. Periodontal parameters were also recorded at baseline and 16 weeks.

RESULTS

Our study results showed statistically significantly more orthodontic tooth movement in the piezocision group (mean difference, 7.60 ± 1.55) than in the control group (mean difference, 5.95±1.28) during the total study period (P = 0.015). In the MOP group, no significant difference in the alignment rate was observed at any time compared to the piezocision and control groups (P >0.05).

CONCLUSIONS

The leveling of mandibular anterior teeth was accelerated by piezocision over 16 weeks, predominantly in the first 12 weeks, whereas MOP had no effect. It was concluded that piezocision is an acceptable procedure and has no destructive effect on the periodontal tissue.

The effect of micro-osteoperforations on the rate of orthodontic tooth movement in animal model: A systematic review and meta-analysis

Introduction

The long passing time for tooth movement (TM) is one of the challenges in orthodontic. complications such as gingival recession, root resorption, and caries are common in orthodontic. To address this, there is an increased tendency to find safe and effective methods to accelerating tooth movement. A surgical method such as micro-osteoperforations (MOP) accelerating the TM. The current meta-analysis aims to investigate the outcome of MOP in accelerating TM in animal studies.

Methods

In the present meta-analysis, we evaluated 6 studies that focused on the effect of MOP on TM with the following keywords: (((MOP* OR micro-osteoperforations*) AND (("accelerating tooth movement " OR " tooth movement" AND " orthodontic tooth movement " OR " orthodontic ") until May 2021.

Results

The results have shown there is significant difference in TM after using MOP (MD: 0.31, 95%CI: 0.20, 0.42, P < 0.00001, I2 = 76%). Subgroup analysis revealed that though experimental duration in both less than 4-week and more than 4-week, the TM were significant difference between MOP and controls. Besides, in both force subgroups including less than 100 g and more than 100g, the TM was a significant difference between MOP and controls.

Conclusion

This meta-analysis found that generally MOP has a positive effect on TM.

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.

Use of Hydrogels to Regulate Orthodontic Tooth Movement in Animal Models: A Systematic Review

The objective of this article is to conduct a systematic review of the literature to contrast the existing evidence regarding the use of hydrogels during and after experimental orthodontic treatment in animals. An extensive search was performed through the electronic databases, Medline, Web of Science and Scopus, from December 2020 to April 2021 for in vivo animal studies. A total of 282 studies were reviewed. Eight studies were included for final revision; four studies were conducted in rats, two in rabbits, one study in mice and one study in guinea pigs. The quality assessment of the eight included studies was performed according to the ARRIVE guidelines and the risk of bias was assessed using the Center for Systematic Review of Laboratory Animal Experimentation tool; in four of the eight articles evaluated, a high risk-of-bias rating was obtained in 40% of the criteria evaluated. In the studies reviewed, the hydrogel acted as a carrier, and inhibition (post-treatment retention) or acceleration of orthodontic tooth movement was assessed according to the active substance used in each of the articles. The uses of hydrogels for transporting active substances to regulate the rate of orthodontic tooth movement remains debatable. Future studies are suggested to evaluate the feasibility of hydrogel as a transport method in humans.

Orthodontically Induced External Apical Root Resorption in Class II Malocclusion

Orthodontic-induced external apical root resorption is one of the idiopathic phenomena as an effect, with force generated through mechanotherapy as the cause and the biological tissues with their diversified variations as witness. It is also classified as iatrogenic as a result of indeterminate application of orthodontic forces with subconscious appreciation of the existing underlying conditions. Numerous factors were identified to relate to this irreversible pathologic condition, but none were proven scientifically. Genetics and salivary markers have proved the reliability with time, but the application became insignificant limiting mostly to the research field. Different assessment methods were also identified to clinically diagnose it both subjectively and objectively. Mostly, it is identified through routine radiographic stage records like orthopantomogram or certain prediction radiographs for root resorption probability assessment like in this case. This case report discusses one such encounter which was experienced after stage 1 and 2 mechanics involving quite a few teeth. Considering the biotype of the individual and tooth morphology, the ongoing treatment was terminated and recovery measures were briefed to uplift the self-esteem of the individual. Furthermore, the prognosis is compromised to be very poor with unpredictability to any other treatment modalities.

Effect of customized vibratory device on orthodontic tooth movement: A prospective randomized control trial

AIMS:

The primary purpose of the present trial was to evaluate the effect of low-frequency (30Hz) vibrations on the rate of canine retraction.

SETTING AND DESIGN:

Single-center, split mouth prospective randomized controlled clinical trial

METHODS AND MATERIAL:

100 screened subjects (aged18–25 years) were selected; out of which 30 subjects having Class I bimaxillary protrusion or Class II div 1 malocclusion, requiring upper 1^st premolar therapeutic extractions, were selected for the study. A split-mouth study design was prepared for the maxillary arch of each selected individual and was randomly allocated into vibration and nonvibration side (control) groups. A customized vibratory device was fabricated for each subject to deliver low-frequency vibrations (30 Hz). Scanned 3D models were prepared sequentially to assess the amount of tooth movement from baseline (T0),(T1), (T2), (T3), and (T4)-4^th month of canine retraction.

STATISTICAL ANALYSIS USED:

Independent “t” test.

RESULTS:

There was no statistically significant differencein the rate of individual canine retraction among the experimental and control groups when the intergroup comparison was done using independent “t” test at T1-T0, (P = 0.954), T2-T1 (P = 0.244), T3-T2 (P = 0.357), and T4-T3 (P = 0.189).

CONCLUSION:

The low-frequency vibratory stimulation of 30 Hz using a customized vibratory device did not significantly accelerate the rate of orthodontic tooth movement.

TRIAL REGISTRATION:

Registered at ctri.nic.in (CTRI/2019/05/019043).

Photobiomodulation impacts the levels of inflammatory mediators during orthodontic tooth movement? A systematic review with meta-analysis

During orthodontic tooth movement (OTM), there is the release of cytokines in the gingival crevicular fluid (GCF) that are supposed to participate in the bone remodeling. This systematic review aimed at assessing the effects of photobiomodulation (PBM) on the levels of these cytokines during OTM. This systematic review according to Cochrane Collaboration guidelines aimed to answer the clinical question following the PICOS strategy. The broad search in the literature was performed before 05 April, 2021 in six electronic databases (Pubmed, Web of Science, Scopus, Embase, Cochrane, Biblioteca Virtual de Saúde) and supplemented by the grey literature. The risk of bias of randomized and non-randomized clinical trials was evaluated by two tools: RoB 2 and ROBINS-I. Mean and standard deviation of cytokine levels was extracted to meta-analysis, and the GRADE system was applied to assess the quality of the evidence. Nine studies were included in this review. Low-level laser therapy (LLLT) was the photobiomodulation type used in most of the studies (n = 8). The wavelengths used varied from 618 to 980 nm and also differed concerning the light emission pattern. LLLT increased the levels of IL-1β, IL-8, OPN, and PGE2, but not TNF-α1, TGF-β1. The levels of IL6, RANKL, and OPG presented conflicting results. LLLT was statistically associated with an increase of IL-1β levels (standard mean difference [SMD] = 1.99; 95% confidence interval = 0.66 to 3.33; p < 0.001) with low certainty of evidence. LLLT may increase the levels of IL-1β and other cytokines; however, the results should be interpreted with caution due to protocol variations between studies, and the few studies added in the meta-analysis.

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.

Possible Mechanisms for the Effects of Sound Vibration on Human Health

This paper presents a narrative review of research literature to “map the landscape” of the mechanisms of the effect of sound vibration on humans including the physiological, neurological, and biochemical. It begins by narrowing music to sound and sound to vibration. The focus is on low frequency sound (up to 250 Hz) including infrasound (1–16 Hz). Types of application are described and include whole body vibration, vibroacoustics, and focal applications of vibration. Literature on mechanisms of response to vibration is categorized into hemodynamic, neurological, and musculoskeletal. Basic mechanisms of hemodynamic effects including stimulation of endothelial cells and vibropercussion; of neurological effects including protein kinases activation, nerve stimulation with a specific look at vibratory analgesia, and oscillatory coherence; of musculoskeletal effects including muscle stretch reflex, bone cell progenitor fate, vibration effects on bone ossification and resorption, and anabolic effects on spine and intervertebral discs. In every category research on clinical applications are described. The conclusion points to the complexity of the field of vibrational medicine and calls for specific comparative research on type of vibration delivery, amount of body or surface being stimulated, effect of specific frequencies and intensities to specific mechanisms, and to greater interdisciplinary cooperation and focus.

lncRNA HHIP-AS1 Promotes the Osteogenic Differentiation Potential and Inhibits the Migration Ability of Periodontal Ligament Stem Cells

Alveolar bone remodeling under orthodontic force is achieved by periodontal ligament stem cells (PDLSCs), which are sensitive to mechanical loading. How to regulate functions of PDLSCs is a key issue in bone remodeling during orthodontic tooth movement. This study is aimed at investigating the roles of lncRNA Hedgehog-interacting protein antisense RNA 1 (HHIP-AS1) in the functional regulation of PDLSCs. First, HHIP-AS1 expression was downregulated in PDLSCs under continuous compressive pressure. Then, we found that the alkaline phosphatase activity, in vitro mineralization, and expression levels of bone sialoprotein, osteocalcin, and osterix were increased in PDLSCs by HHIP-AS1. The results of scratch migration and transwell chemotaxis assays revealed that HHIP-AS1 inhibited the migration and chemotaxis abilities of PDLSCs. In addition, the RNA sequencing data showed that 356 mRNAs and 14 lncRNAs were upregulated, including receptor tyrosine kinase-like orphan receptor 2 and nuclear-enriched abundant transcript 1, while 185 mRNAs and 6 lncRNAs were downregulated, including fibroblast growth factor 5 and LINC00973, in HHIP-AS1-depleted PDLSCs. Bioinformatic analysis revealed several biological processes and signaling pathways related to HHIP-AS1 functions, including the PI3K-Akt signaling pathway and JAK-STAT signaling pathway. In conclusion, our findings indicated that HHIP-AS1 was downregulated in PDLSCs under compressive pressure, and it promoted the osteogenic differentiation potential and inhibited the migration and chemotaxis abilities of PDLSCs. Thus, HHIP-AS1 may be a potential target for accelerating tooth movement during orthodontic treatment.

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.

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 Triptolide On Tooth Movement And Root Resorption In Rats

Purpose

The aim of this study was to investigate the effects of triptolide on the tooth movement and root resorption in rats during orthodontic treatment.

Material and methods

A total of 48 male Wistar rats were divided into three groups of 16 each. The right maxillary first molars of rats were drawn mesially by closed coil nickel-titanium spring with a force of 50 g. The two experimental groups received intraperitoneal injections of triptolide for 14 days at a dose of 15 µg/kg/day and 30 µg/kg/day, respectively. The control group received vehicle injections. After 14 days, the rats were humanely killed. The amount of tooth movement was measured. Eight rats from each group were randomly chosen for analysis of the percentage of root resorption area by scanning electron microscopy. For the remaining eight rats in each group, the H&E staining, tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemistry analysis were performed.

Results

The amount of tooth movement and the ratio of root resorption area were significantly decreased in the triptolide-treated rats. The number of TRAP-positive cells was significantly lower in triptolide-treated groups. Moreover, the expression of nuclear factor kappa B ligand (RANKL) was reduced. In contrast, the expression of osteoprotegerin was significantly up-regulated. In the tension side, the expressions of runt-related transcription factor 2 and osteocalcin were significantly enhanced by triptolide injection.

Conclusion

Triptolide injection could arrest orthodontic tooth movement and reduce root resorption in rats via inhibition of osteoclastogenesis. In addition, triptolide may exert a positive effect on osteoblastogenesis.

[Adjunctive interventions to accelerate orthodontic tooth movement]

Orthodontic treatment is a time-consuming process whose duration usually takes 2-3 years. In general, long-term treatment duration possesses higher risks of complications, which may have adverse impact on patients. Therefore, exploring safe and effective adjunctive interventions to accelerate orthodontic tooth movement and shortening the treatment duration are of profound clinical significance. Currently, numerous adjunctive interventions have been generated and developed to accelerate orthodontic tooth movement, which can be divided into two main categories: surgical and non-surgical. However, an intervention that is widely accepted as a routine practice in orthodontic clinic is lacking. This article aims to review com-mon adjunctive interventions used to accelerate orthodontic tooth movement. This review can be used as a basis to guide clinical practice, shorten treatment duration, and improve patients' prognosis.

Effect of micro-osteoperforation on the rate of orthodontic tooth movement—a systematic review and a meta-analysis

Background

The micro-osteoperforation can be used to increase the rate of tooth movement, simplify complex orthodontic movements, and also help adjust the anchorage but there are conflicting reports on the effectiveness and adverse effects of this intervention.

Objectives

The aim of our systematic review and meta-analysis was to evaluate the effects of micro-osteoperforation on the rate of tooth movement in patients undergoing orthodontic treatment.

Search methods

A comprehensive search of MEDLINE, ISI web of science, EMBASE, Scopus, and CENTRAL online databases for studies measuring the effects of micro-osteoperforation on the rate of orthodontic tooth movement from inception to February 2019 was performed.

Selection criteria

Based on the PICO model, human studies which evaluated the effects of MOP on the rate of tooth movement in patients undergoing orthodontic treatment were selected for this review.

Data collection and analysis

The relevant data from the eligible studies were extracted using piloted custom extraction forms. The data were combined and analysed using inverse-variance random-effect meta-analysis and the mean difference was used for comparing the outcome measures.

Results

Six randomized clinical trials were finally included in this meta-analysis. The rate of canine retraction per month was significantly higher in the MOP group [mean difference (MD) = 0.45 mm, 95% CI = 0.17–0.74]. These results were similar with regard to different malocclusions, the jaw on which it was performed, and MOP methods. The patients did not report any significant differences in terms of pain severity levels after MOP. With regard to the adverse effects, one study reported higher amounts of root resorption among patients undergoing MOP.

Conclusions

The rate of tooth movement was increased after performing MOP but in at least one study higher root resorption was observed. Therefore, the use of MOP can be recommended after weighing the benefits and disadvantages this intervention can bring for each patient.

Registration

The protocol for this review was registered via crd.york.ac.uk/prospero with the ID CRD42019115499.

A parallel randomized controlled trial examining the effects of rhythmic sensory stimulation on fibromyalgia symptoms

This double-blind, two-arm parallel randomized controlled trial investigated the effects of gamma-frequency rhythmic sensory stimulation on fibromyalgia. We were interested in whether rhythmic sensory stimulation would promote significant changes in fibromyalgia and associated symptoms, and whether treatment effects would differ between two distinct treatment parameters. Fifty patients with a formal diagnosis of fibromyalgia were randomly assigned to two test groups. One group received vibrotactile stimulation from a continuous sine wave single-frequency stimulation (40 Hz) for 30 minutes, five days per week, over five weeks, concomitant with usual care. The second group completed the same treatment protocol but received a different stimulation, consisting of random and intermittent complex wave gamma-range vibrotactile stimulation. Fibromyalgia symptoms, pain severity and interference, depression symptoms, quality of life and sleep quality were assessed at baseline and post-intervention. Results indicated that there were statistically significant changes from baseline to post-treatment in measures of fibromyalgia symptom severity, pain interference, depression, and sleep quality. However, treatment outcomes did not differ significantly between groups. These findings provide preliminary evidence that gamma-frequency rhythmic vibroacoustic stimulation may decrease fibromyalgia symptoms and ease associated comorbidities, opening new avenues for further investigation of the effects of rhythmic sensory stimulation on chronic pain conditions.

[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.

Differential Efficacy of 2 Vibrating Orthodontic Devices to Alter the Cellular Response in Osteoblasts, Fibroblasts, and Osteoclasts

Modalities that increase the rate of tooth movement have received considerable attention, but direct comparisons between devices are rare. Here, we contrasted 2 mechanical vibratory devices designed to directly transfer vibrations into alveolar bone as a means to influence bone remodeling. To this end, 3 cells types intimately involved in modulating tooth movements-osteoblasts, periodontal ligament fibroblasts, and osteoclasts-were subjected to in vitro vibrations at bout durations prescribed by the manufacturers. As quantified by an accelerometer, vibration frequency and peak accelerations were 400% and 70% greater in the VPro5 (Propel Orthodontics) than in the AcceleDent (OrthoAccel Technologies) device. Both devices caused increased cell proliferation and gene expression in osteoblasts and fibroblasts, but the response to VPro5 treatment was greater than for the AcceleDent. In contrast, the ability to increase osteoclast activity was device independent. These data present an important first step in determining how specific cell types important for facilitating tooth movement respond to different vibration profiles. The device that engendered a higher vibration frequency and larger acceleration (VPro5) was superior in stimulating osteoblast and fibroblast cell proliferation/gene expression, although the duration of each treatment bout was 75% shorter than for the AcceleDent.