Accelerate Tooth Movement Research Articles

Single-cell sequencing decodes the secrets of the RAP phenomenon of corticotomy.

Corticotomy-assisted tooth movement is commonly performed in clinics, however, its time-limited efficacy and the fear of surgery among patients significantly limit its clinical application. Hence, researchers have investigated non-invasive methods to accelerate tooth movement. However, the molecular mechanisms underlying corticotomy-assisted tooth movement are not fully understood. Micro-CT and TRAP stain were used to tooth movement and bone resorption. Single-cell RNA sequencing was used to study the transcriptome heterogeneity of macrophages after corticotomy. Transmission electron microscopy and iron ion detection was used to evaluate ferroptosis and iron metabolism. In addition, we carried out immunohistochemistry, quantitative real-time and flow cytometry verify the effect of iron on macrophage polarization. Single-cell RNA sequencing of digested alveolar bone identified a significant increase in iron metabolism-related genes post-corticotomy. Macrophages play a central role in this field. Following the dimensionality reduction of macrophages, we revealed a new developmental state via pseudotime analysis post-corticotomy. SCENIC analysis revealed that Atf3 is a key transcription factor influencing this new state. We found that Atf3+ macrophages were closely associated with osteoclasts. Moreover, cell chat revealed an increase in cellular communication between Atf3+ macrophages and other cell types after corticotomy. These findings suggested that Atf3+ macrophages might play a key role in corticotomy-accelerated tooth movement, thus providing potential targets for drug development.

The Effect of Corticotomy-Assisted Orthodontic Therapy (CAOT) or Periodontally Accelerated Osteogenic Orthodontics (PAOO) on Bone Remodeling and the Health of Periodontium: A Systematic Review of Systematic Reviews.

Background: Orthodontic treatment involves moving teeth within the alveolar ridge. Bone remodeling is associated with the activity of osteoblasts and osteoclasts. Procedures such as corticotomy-assisted orthodontic therapy (CAOT) or periodontally accelerated osteogenic orthodontics (PAOO) are intended to reduce bone density and negative stress on the grip side and therefore limit bone resorption during orthodontic movement or add bone substitute material so that the tooth does not cross the vestibular plate. Methods: The study was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The study design was defined in the PICO format-Population (P): patients with full permanent dentition, both adolescents and adults; Intervention (I): orthodontic treatment with fixed appliances using additional supportive treatments such as CAOT or PAOO; Comparison (C): assessment of the impact of additional treatments during orthodontic treatment on the remodeling of the alveolar bone and the condition of the periodontium; Result (O): statistically significant/non-significant differences in the condition of the alveolar bone before and after orthodontic treatment. Search filters include the time of publication of the article, systematic reviews from the last five years, and publications that appeared in English. The information provided in the abstracts of systematic reviews that describe the effects of additional procedures during orthodontic treatment such as CAOT or PAOO on the health of periodontium was analyzed. Articles unrelated to the subject of the planned study and those in which tooth movement acceleration was analyzed were excluded. Results: Eight articles were selected in which a total number of 835 subjects took part. The changes in bone density and effects on periodontium were different after CAOT and PAOO. Conclusions: The validity of CAOT and PAOO procedures remains controversial. Better results are obtained when combined with tissue augmentation or thickening of the gingival phenotype rather than as stand-alone procedures, as their uses to protect periodontal tissues are limited.

Awareness to Orthodontics among a Sample of Final Year Dental Students

Abstract Objective Because of esthetic demand, awareness about orthodontic treatment has increased nowadays, especially among young people and adolescents, in addition to the fact that knowledge of orthodontics and various details of it is more significant among dental students according to what they learned in their curricula and their examination and observation of many cases of malocclusion. The objective of the present study was to evaluate the awareness of the final year of undergraduate dental students toward orthodontics. Materials and Methods About 532 (320 females and 212 males) students in the fifth year of six Iraqi universities were invited to participate in this questionnaire distributed via the Google classroom. This questionnaire included 20 questions about orthodontics. Pearson's chi-square test evaluated the gender and universities differences. Results In general, the awareness responses were very high in most of the questions answered except in three questions in which the percentage of positive answers varies from 49 to 76%. Also, there were no significant gender differences in 17 question answers, and only 3 showed significant gender differences. Females expressed a high level of awareness than males. Conclusion The high and close level of awareness expressed by students' responses in this study revealed the integrated education in orthodontic sciences in Iraqi dental colleges in different universities, except in some questions that deal with topics about the acceleration of tooth movement and the relation between vitamin D3 and teeth movement.

The effect of single versus multiple piezocisions on the rate of canine retraction: a randomized controlled trial

BackgroundPiezocision is a minimally invasive surgical method aiming to accelerate tooth movement. However, its effect was found to be transient, appertaining to the regional acceleratory phenomenon (RAP). Hence, the aim of the study was to evaluate the effect of single and multiple piezocisions on the rate of orthodontic tooth movement (OTM). Moreover, the impact of both protocols on canine tipping and orthodontically induced inflammatory root resorption (OIIRR) has been assessed.MethodsThirty indicated patients for the therapeutic extraction of maxillary first premolars were enlisted in this split-mouth study, and they were randomly split into two equal groups, each including 15 subjects. In the Single Application Group (SAG), one side of the maxillary arch arbitrarily received a single piezocision before the onset of canine retraction, whereas in the Multiple Application Group (MAG), piezocisions were randomly performed on one side, three times on a monthly basis, over the 12-week study period. The contralateral sides of both groups served as the controls. Canine retraction was carried out bilaterally using nickel-titanium closed-coil springs, delivering 150 g of force, and the rate of tooth movement, as well as canine tipping were evaluated on a monthly basis, over a 3-month period. Cone-bean computed tomography scans were also conducted pre- and post- canine retraction, and OIIRR was assessed using Malmgren Index.ResultsThe reported outcomes revealed a significant increase in the amount of canine retraction, canine tipping, as well as root resorption scores on the experimental sides in both groups SAG and MAG post-retraction (p < 0.001). However, upon comparing the experimental sides in both groups, non-significant differences have been observed between them regarding all the assessed outcomes (p > 0.05).ConclusionsSingle and multiple piezocisions effectively accelerate OTM in comparison to conventional orthodontic treatment, with relative outcomes reported by both intervention frequencies. Accordingly, single piezocision is recommended as an adjunct to OTM. Furthermore, significant tooth tipping as well as a significantly higher root resorption risk accompanies both single and multiple piezocision applications in conjunction with OTM.Name of the RegistryClinicaltrials.govTrial Registration NumberNCT05782088Date of Registration23/03/2023 “Retrospectively registered”.URLhttps://clinicaltrials.gov/ct2/show/NCT05782088

Comparison of various modes of acceleration of orthodontic tooth movement- A clinical study

The objective of the present study is to evaluate the effects of Micro-osteoperforations (MOPs), Corticision, Low Level Laser Therapy (LLLT) and Platelet Rich Plasma (PRP) on the rate of orthodontic tooth movement. Randomly10 patients were selected in each study group. All the studies had a split-mouth study design. All the patients were bonded with MBT 0.022 X 0.028 inch brackets and maxillary canine retraction was performed on 0.019 X 0.025 stainless steel wires with different methods of accelerating tooth movement. Data was collected from the orthodontic study models prepared from alginate impression taken at each appointment interval. The results of the study revealed that the amount of maxillary canine retraction was rapid in all the groups as compared to conventional method of orthodontic tooth movement and the results conclude thatmicro-osteoperfortaions showed better rate of accelerated orthodontic tooth movement as compared to other methods.

Orthodontists’ perception and attitude toward accelerated orthodontic treatments in Australia

Abstract Introduction The purpose of this cross-sectional study was to survey the perception and attitude of Australian orthodontists toward accelerated orthodontic treatments. Methods An online questionnaire was distributed to 427 members of the Australian Society of Orthodontists. The questions related to: clinic demographics, familiarity with appliances/procedures to accelerate orthodontic treatment, the use of appliances/procedures to accelerate orthodontic treatment, and satisfaction with the outcomes when employing these appliances/procedures. Results The response rate was 42.38%. Of the respondents, 26.6% used customised fixed appliances which provided satisfactory outcomes. A small proportion of the respondents routinely used adjunctive procedures to accelerate treatment: 3.5% (n=6) corticotomies, 1.2% (n=2) piezocision, and 1.2% (n=2) intraoral vibrating devices. Conclusion Although a significant number of Australian orthodontists use customised fixed appliances to improve the efficiency of orthodontic treatment, the use of adjunctive procedures to accelerate tooth movement remains very low. Further research is needed to understand the possible limitations and restrictions surrounding this area of practice.

Pain and root resorption due to surgical interventions to accelerate tooth movement in orthodontics: A systematic review and meta-analysis.

There are several publications that show the efficacy of surgical interventions in accelerating the rate of tooth movement in orthodontics. Consequently, possible adverse effects must also be evaluated. The aim of the present study was to compare the perception of pain and root resorption between orthodontic treatment with a surgical acceleration intervention vs. conventional orthodontic treatment. An electronic search was conducted in the MEDLINE, Scopus, Web of Science (WoS), ScienceDirect, Cochrane Library, and Virtual Health Library (VHL) databases up to September 12, 2022. Randomized or non-randomized, controlled, parallel-arm or split-mouth clinical trials were included. Fixed-and random-effects meta-analyses were performed with regard to heterogeneity. The risk of bias (RoB) was assessed using the RoB 2.0 and ROBINS-I tools. A total of 1,395 articles were initially retrieved, 40 studies were finally included in the review and 15 studies were eligible for quantitative analysis. The meta-analysis showed a significant difference in pain perception between acceleration surgery vs. conventional orthodontics at 24 h (p = 0.040); however, this difference was not significant at 7 days (p = 0.080). Overall, the patients who underwent any acceleration procedure presented significantly less resorption as compared to those who were applied conventional treatment (p < 0.001). A similar significant difference was found in retraction movements (p < 0.001) and alignment movements (p = 0.030). In the first 24 h, surgical interventions for the acceleration of tooth movement produce a greater perception of pain as compared to conventional orthodontic treatment, but the perception is similar after 7 days. Acceleration surgery results in less root resorption - in alignment movements, and especially in retraction movements.

Effect of low-level laser therapy on en masse retraction in females with bimaxillary dentoalveolar protrusion : A single-center randomized clinical trial.

Acceleration of tooth movement has gained remarkable attention during the last decade. The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on en masse retraction of upper anterior teeth in adult women with bimaxillary dentoalveolar protrusion. In this two-arm parallel trial, 36women with bimaxillary dentoalveolar protrusion were randomly divided into two equal groups. Eligibility criteria included classI Angle molar relationship, good general and oral health as well as no systemic disease or syndrome. Four temporary anchorage devices (TADs) were used in the upper and lower arches for anchorage purposes. A 0.019×0.025-inch stainless steel wire with crimped hooks just distal to the maxillary canines was inserted. Nickle titanium (NiTi) closed coil springs (200 g/side) were employed for en masse retraction following extraction of the first premolars. In the laser group (LG), retraction of the upper anterior teeth was done along with the application of LLLT on days0, 3, 7, and 14 after extraction and then repeated biweekly until the end of retraction. Retraction was completed without LLLT application in the nonlaser group (NLG). Data concerning the rate of retraction as well as first molars and anterior positional changes were gained from digitized models and cone beam computed tomography (CBCT) scans taken just before extraction and at the end of retraction. Treatment-associated pain and root resorption were evaluated using visual analogue scale (VAS) and CBCT scans, respectively. Four patients dropped out prior to follow-up. The duration of retraction was 10.125 ± 2.876 and 13.643 ± 3.455 months in the LG and NLG, respectively. The LG showed astatistically significant faster rate of en masse retraction (0.833 ± 0.371 mm/month) compared to the NLG (0.526 ± 0.268 mm/month; P ≤ 0.035). The observed root resorption was significantly less in the LG (P ≤ 0.05) with comparable pain scores in both groups. Within the constraints of the parameters of the LLLT used in the current study and despite the statistically significant results on the rate of en masse retraction and the associated root resorption, LLLT did not demonstrate aclinically relevant effect that justifies its use to enhance en masse retraction. Clinicaltrials.gov TRIAL REGISTRATION NUMBER: NCT05183451 DATE OF REGISTRATION: January10, 2022, "Retrospectively registered" URL OF TRIAL REGISTRY RECORD: https://www. gov/study/NCT05183451.

Effective Parameters for Orthodontic Tooth Movement Acceleration with Photobiomodulation: An Umbrella Review.

Objective: To answer this research question: What are the effective wavelength, power, and energy density parameters for achieving dental movement acceleration? Background Data: Photobiomodulation (PBM) has been clinically studied for its ability to accelerate dental movements in orthodontics. However, its effectiveness is dose dependent. Methods: The search was carried out in PubMed, SCOPUS, and ISI Web of Science. The quality of the included systematic reviews was performed using the AMSTAR 2 tool. The risk of bias was assessed using the ROBIS tool. Results: In total, 29 articles in PubMed, 75 in Scopus, and 61 in ISI Web of Science. Finally, only five systematic reviews were included. Conclusions: The results showed the range from 730 to 830 nm as the most effective range of wavelength to accelerate the orthodontic dental movement. A power range of 0.25-200 mW, with emphasis on the direct correlation between power, wavelength, and energy density. Energy density has not been adequately reported in the most randomized controlled clinical trials.

Involvement of RAMP1/p38MAPK signaling pathway in osteoblast differentiation in response to mechanical stimulation: a preliminary study

ObjectiveThe present study aimed to investigate the underlying mechanism of mechanical stimulation in regulating osteogenic differentiation.Materials and methodsOsteoblasts were exposed to compressive force (0–4 g/cm2) for 1–3 days or CGRP for 1 or 3 days. Expression of receptor activity modifying protein 1 (RAMP1), the transcription factor RUNX2, osteocalcin, p38 and p-p38 were analyzed by western blotting. Calcium mineralization was analyzed by alizarin red straining.ResultsUsing compressive force treatments, low magnitudes (1 and 2 g/cm2) of compressive force for 24 h promoted osteoblast differentiation and mineral deposition whereas higher magnitudes (3 and 4 g/cm2) did not produce osteogenic effect. Through western blot assay, we observed that the receptor activity-modifying protein 1 (RAMP1) expression was upregulated, and p38 mitogen-activated protein kinase (MAPK) was phosphorylated during low magnitudes compressive force-promoted osteoblast differentiation. Further investigation of a calcitonin gene-related peptide (CGRP) peptide incubation, a ligand for RAMP1, showed that CGRP at concentration of 25 and 50 ng/ml could increase expression levels of RUNX2 and osteocalcin, and percentage of mineralization, suggesting its osteogenic potential. In addition, with the same conditions, CGRP also significantly upregulated RAMP1 and phosphorylated p38 expression levels. Also, the combination of compressive forces (1 and 2 g/cm2) with 50 ng/ml CGRP trended to increase RAMP1 expression, p38 activity, and osteogenic marker RUNX2 levels, as well as percentage of mineralization compared to compressive force alone. This suggest that RAMP1 possibly acts as an upstream regulator of p38 signaling during osteogenic differentiation.ConclusionThese findings suggest that CGRP-RAMP1/p38MAPK signaling implicates in osteoblast differentiation in response to optimal magnitude of compressive force. This study helps to define the underlying mechanism of compressive stimulation and may also enhance the application of compressive stimulation or CGRP peptide as an alternative approach for accelerating tooth movement in orthodontic treatment.

Static magnetic field-induced IL-6 secretion in periodontal ligament stem cells accelerates orthodontic tooth movement

Static magnetic field (SMF) promoting bone tissue remodeling is a potential non-invasive therapy technique to accelerate orthodontic tooth movement (OTM). The periodontal ligament stem cells (PDLSCs), which are mechanosensitive cells, are essential for force-induced bone remodeling and OTM. However, whether and how the PDLSCs influence the process of inflammatory bone remodeling under mechanical force stimuli in the presence of SMFs remains unclear. In this study, we found that local SMF stimulation significantly enhanced the OTM distance and induced osteoclastogenesis on the compression side of a rat model of OTM. Further experiments with macrophages cultured with supernatants from force-loaded PDLSCs exposed to an SMF showed enhanced osteoclast formation. RNA-seq analysis showed that interleukin-6 (IL-6) was elevated in force-loaded PDLSCs exposed to SMFs. IL-6 expression was also elevated on the pressure side of a rat OTM model with an SMF. The OTM distance induced by an SMF was significantly decreased after injection of the IL-6 inhibitor tocilizumab. These results imply that SMF promotes osteoclastogenesis by inducing force-loaded PDLSCs to secrete the inflammatory cytokine IL-6, which accelerates OTM. This will help to reveal the mechanism of SMF accelerates tooth movement and should be evaluated for application in periodontitis patients.

Low-intensity pulsed ultrasound promotes the osteogenesis of mechanical force-treated periodontal ligament cells via Piezo1.

Low-intensity pulsed ultrasound (LIPUS) can accelerate tooth movement and preserve tooth and bone integrity during orthodontic treatment. However, the mechanisms by which LIPUS affects tissue remodeling during orthodontic tooth movement (OTM) remain unclear. Periodontal ligament cells (PDLCs) are pivotal in maintaining periodontal tissue equilibrium when subjected to mechanical stimuli. One notable mechano-sensitive ion channel, Piezo1, can modulate cellular function in response to mechanical cues. This study aimed to elucidate the involvement of Piezo1 in the osteogenic response of force-treated PDLCs when stimulated by LIPUS. After establishing rat OTM models, LIPUS was used to stimulate rats locally. OTM distance and alveolar bone density were assessed using micro-computed tomography, and histological analyses included hematoxylin and eosin staining, tartrate-resistant acid phosphatase staining and immunohistochemical staining. GsMTx4 and Yoda1 were respectively utilized for Piezo1 functional inhibition and activation experiments in rats. We isolated human PDLCs (hPDLCs) in vitro and evaluated the effects of LIPUS on the osteogenic differentiation of force-treated hPDLCs using real-time quantitative PCR, Western blot, alkaline phosphatase and alizarin red staining. Small interfering RNA and Yoda1 were employed to validate the role of Piezo1 in this process. LIPUS promoted osteoclast differentiation and accelerated OTM in rats. Furthermore, LIPUS alleviated alveolar bone resorption under pressure and enhanced osteogenesis of force-treated PDLCs both in vivo and in vitro by downregulating Piezo1 expression. Subsequent administration of GsMTx4 in rats and siPIEZO1 transfection in hPDLCs attenuated the inhibitory effect on osteogenic differentiation under pressure, whereas LIPUS efficacy was partially mitigated. Yoda1 treatment inhibited osteogenic differentiation of hPDLCs, resulting in reduced expression of Collagen Ⅰα1 and osteocalcin in the periodontal ligament. However, LIPUS administration was able to counteract these effects. This research unveils that LIPUS promotes the osteogenesis of force-treated PDLCs via downregulating Piezo1.

Evaluation of Dentist Perception of Platelet Rich Plasma (PRP) for Accelerated Tooth Movement - Cross Sectional Survey.

The current survey was conducted to assess the knowledge, awareness and perception of platelet-rich plasma (PRP) on accelerated tooth movement among dentist present in the state of Tamil Nadu. Tamil Nadu dentists were the subjects of the cross-sectional questionnaire survey. 500 participants completed self-administered questionnaires about their knowledge, awareness, and perception of PRP's effect on accelerated tooth movement. The Statistical Package for the Social Sciences (SPSS) (V 22.0) was used to do the statistical analysis. It computed the frequency distribution.The result showed that 466 (93.2%) had prior knowledge of PRP, whereas 34 (6.4%) had no previous experience with it. A total of 156 (31.2%) dentists were aware that PRP procedures are used for teeth rotation and canine retraction.15.2% of participants stated that PRP facilitates accelerated tooth movement.Therefore, results of the study show that the dentists were a little aware of PRP as an additional therapeutic strategy for accelerating tooth movement.More awareness required among the dentist regarding application and its benefits of PRP in accelerated tooth movement.

Accelerated Orthodontic Treatment using Biomodulation: A Randomized Clinical Trial

ABSTRACT Background: Orthodontic treatment often spans several months or even years, which can be burdensome for patients. Biomodulation techniques have emerged as potential strategies to expedite orthodontic tooth movement. Materials and Methods: A randomized clinical trial was conducted with a sample of 60 orthodontic patients, aged 12–30 years, requiring fixed appliance therapy. Patients were randomly assigned to either the biomodulation group (n = 30) or the control group (n = 30). The biomodulation group received low-level laser therapy (LLLT) along with traditional orthodontic treatment, while the control group received conventional orthodontic treatment without LLLT. Treatment duration, pain perception, and orthodontic tooth movement were assessed during the study period. Results: The results demonstrated a significant reduction in treatment duration in the biomodulation group compared to the control group. The biomodulation group exhibited a 30% reduction in overall treatment time, with an average treatment duration of 8.4 months, while the control group required an average of 12 months (P &lt; 0.001). Pain perception during orthodontic adjustments was lower in the biomodulation group. Additionally, biomodulation was associated with a statistically significant increase in the rate of tooth movement, as evidenced by a 20% reduction in the time required to achieve desired tooth alignment (P &lt; 0.01). Conclusion: Biomodulation through low-level laser therapy represents a promising adjunct to traditional orthodontic treatment, significantly accelerating tooth movement and reducing treatment duration.

The biological effects of Piezocision™ on bone for accelerated tooth movement: A systematic review of animal studies

Objectives: This systematic review aimed to assess the biological response at tissue, cellular, and molecular levels following Piezocision™ surgery, and its efficacy in accelerating orthodontic tooth movement.Material and methods: A systematic review of the literature was conducted across 4 databases following the PRISMA guidelines up to May 2022. Prospective controlled animal studies involving healthy animals under active orthodontic treatment assisted by corticotomy performed with a piezotome (Piezocision™) published in the English language without time restrictions were included. The article selection, data extraction and risk of bias assessment (SYRCLE tool) were performed by two independent blinded review authors.Results: Out of 738 articles screened, 10 studies were included with various level of bias. Biological responses were categorized into tissue, cellular, and molecular levels. Tissue-level changes included a global decrease in bone mineral content post-Piezocision™. At the cellular level, increased bone turnover activity was noted. Molecularly, elevated RANKL and OPG expression, along with increased TRAP+ and cytokines, were observed after Piezocision™. Studies confirmed Piezocision's efficacy, reporting 1.35 to 3.26 times faster tooth movements, peaking between the 3rd and 50th day post-surgery. Biological responses were transient, reversible, and proportional to surgical insult, with reactivation possible through a second Piezocision™.Conclusions: After Piezocision™ surgery, a transient and reversible biological response was described at the tissue, cellular and molecular levels, which induced faster orthodontic tooth movements. This biological response could be re-activated by an additional Piezocision™ and is proportional to the surgical injury. Systematic review registration: Prospero CRD42022303237.

Evaluation of cellular viability in chitosan/L-arginine hydrogels.

There is a lack of studies evaluating the toxicity of nitric oxide (NO) precursors in chitosan/L-arginine hydrogels and their topical administration. However, clarifying the characteristics of these elements is essential for their possible use in non-surgical techniques of tooth movement acceleration. Such characteristics include interaction with different cell types, metabolism and drug safety. This in vitro study aimed to assess the cytotoxicity of chitosan hydrogels on human HeLa cells using different concentrations of L-arginine. The hydrogels were synthesized in a materials engineering laboratory, with a controlled environment, using 4 different L-arginine concentrations of 0%, 10%, 15%, and 20%. Once the hydrogels were prepared, their physical and chemical properties were characterized, and viability analysis was performed using 2 different methods, including a 48-h assay with Artemia salina nauplii and a 24-h cell culture with human HeLa cells followed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation assay. Data analysis was performed using a Mann-Whitney U test to evaluate positive and negative controls in the cell culture, with a significance level of 0.01. A Wilcoxon paired test contrasted the 24-h compared to 48-h Artemia salina assays, with a Kruskal-Wallis and post hoc Dunn test used to compare groups using a significance level of 0.05. In the more viscous hydrogels, Artemia salina nauplii decreased drastically in 24 h, while the 15% and 20% hydrogels had no statistical differences from the negative control. The 10% and 20% hydrogels were statistically different from the negative control when comparing cell culture data. Our findings suggest that chitosan/L-arginine hydrogels could be used in humans without toxic effects. However, more trials and tests are needed to evaluate tooth movement rate during orthodontic treatment.

Low-intensity pulsed ultrasound reduces alveolar bone resorption during orthodontic treatment via Lamin A/C-Yes-associated protein axis in stem cells.

The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years, which also may lead to some complications such as alveolar bone resorption or tooth root resorption. Low-intensity pulsed ultrasound (LIPUS), a noninvasive physical therapy, has been shown to promote bone fracture healing. It is also reported that LIPUS could reduce the duration of orthodontic treatment; however, how LIPUS regulates the bone metabolism during the orthodontic treatment process is still unclear. To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement (OTM) model and explore the underlying mechanisms. A rat model of OTM was established, and alveolar bone remodeling and tooth movement rate were evaluated via micro-computed tomography and staining of tissue sections. In vitro, human bone marrow mesenchymal stem cells (hBMSCs) were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction, Western blot, alkaline phosphatase (ALP) staining, and Alizarin red staining. The expression of Yes-associated protein (YAP1), the actin cytoskeleton, and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA (siRNA) application via immunofluorescence. The force treatment inhibited the osteogenic differentiation potential of hBMSCs; moreover, the expression of osteogenesis markers, such as type 1 collagen (COL1), runt-related transcription factor 2, ALP, and osteocalcin (OCN), decreased. LIPUS could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by force. Mechanically, the expression of LaminA/C, F-actin, and YAP1 was downregulated after force treatment, which could be rescued by LIPUS. Moreover, the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA treatment. Consistently, LIPUS increased alveolar bone density and decreased vertical bone absorption in vivo. The decreased expression of COL1, OCN, and YAP1 on the compression side of the alveolar bone was partially rescued by LIPUS. LIPUS can accelerate tooth movement and reduce alveolar bone resorption by modulating the cytoskeleton-Lamin A/C-YAP axis, which may be a promising strategy to reduce the orthodontic treatment process.

Use of electrical stimulation for accelerated orthodontics in humans: a systematic review and meta-analysis.

The main objective of this systematic review is to comprehensively evaluate all the relevant studies to evaluate the effectiveness of electrical stimulation to accelerate orthodontic tooth movement in human patients. Using a suitable search strategy, various databases like PubMed, CENTRAL, Scopus and Google Scholar were surveyed for relevant randomized controlled trials (RCTs); after which a hand search of related orthodontic journals was completed. The risk of bias of studies was checked using Cochrane's ROB-2 tool. The quality of evidence of the included studies was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. Rate of orthodontic tooth movement was compared and thus efficiency of electrical stimulation to accelerate tooth movement was assessed. Meta-analysis was done on 2 studies out of the 4; rate of orthodontic tooth movement was compared at two time periods after start of treatment (3rd month and 5th month) with standardized mean difference (SMD) as summary estimate, with p < 0.05 denoting statistical significance. Publication bias was checked using a funnel plot. Via exploration of the online databases and hand searching,1080 studies were found after removing duplicates. After full text assessment, 13 studies in total were selected that used electrical stimulation, out of which 4 studies were included in the qualitative analysis as they met the inclusion criteria. The meta-analysis was done for 3rd month and 5th month with SMD as 0.69(-1.26-0.12) and 1.64(-3.44-0.16), respectively. The strength of evidence in the meta-analysis is moderate. There was no publication bias as shown by funnel plot. The studies included showed increased risk of selection and performance bias. Also due to the limited number of studies available, there was difficulty in reaching definitive conclusions. The meta-analysis showed a significant difference among the control and experimental group for the 3rd month. Even though a positive correlation is found between electrical stimulation and acceleration of orthodontic tooth movement, it is advised to conduct further studies, particularly with human participants, to establish a more conclusive outcome. This review has received no funding. The protocol for the study was registered in the Prospective Registration of Systematic Review (PROSPERO)(CRD42023495077).

Micro-Osteoperforations Accelerate Tooth Movement without Exacerbating the Progression of Root Resorption in Rats.

A recent study reported that micro-osteoperforations (MOPs) accelerated tooth movement by activating alveolar bone remodeling. However, very little is known about the relationship between MOPs and external apical root resorption during orthodontic treatment. In this study, in order to investigate the mechanism through which MOPs accelerate tooth movement without exacerbating the progression of root resorption, we measured the volume of the resorbed root, and performed the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) method on exposed MOPs during experimental tooth movements in rats. Male Wistar rats (11 weeks old) were divided into three groups: 10 g orthodontic force (optimal force) applied to the maxillary first molar (optimal force: OF group), 50 g orthodontic force application (heavy force: HF group), and 10 g force application plus three small perforations of the cortical plate (OF + MOPs group). On days 1, 4, 7, 10, and 14 after force application, the tooth movement and root volume were investigated by micro-computed tomography. Furthermore, the number of apoptotic cells in the pressured sides of the periodontal ligament (PDL) and surrounding hard tissues were determined by TUNEL staining. The OF + MOPs group exhibited a 1.8-fold increase in tooth movement on days 7, 10, and 14 compared with the OF group. On days 14, the HF group had a higher volume of root loss than the OF and OF + MOPs groups. On the same day, the number of TUNEL-positive cells in the HF group increased at the root (cementum) site whereas that in the OF group increased at the alveolar bone site. Furthermore, the number of TUNEL-positive cells in the OF + MOPs group increased at the alveolar bone site compared with the OF group. These results suggest that MOPs accelerate orthodontic tooth movement without exacerbating the progression of root resorption.

Correlation of salivary cytokine IL-17A and 1,25 dihydroxycholecalciferol in patients undergoing orthodontic treatment.

The management of malocclusion has developed greatly in terms of treatment simulation and biomechanics, but treatment duration has been a great concern to the clinician as well as the patient. 1-25dihydroxycholecalciferol (biologically active form of Vitamin D) stimulates both osteoclasts and osteoblasts and was found to be the most significant in Orthodontic Tooth Movement acceleration. Inflammatory cytokines like IL-17A also play an important role in osteoclastogenesis and can enhance the rate of Orthodontic Tooth Movement.To perform a simultaneous evaluation of pro-inflammatory salivary cytokine IL-17A and salivary 1-25dihydroxycholecalciferol and to correlate their role on orthodontic tooth movement.A prospective cohort study was conducted among n = 97 patients. Saliva samples were collected from the patients at three phases of the orthodontic treatment, centrifuged and stored at 4℃ for evaluation of salivary 1-25dihydroxycholecalciferol levels and Pro-inflammatory cytokine IL-17A using ELISA.The mean salivary 1-25dihydoxycholecalciferol levels were 41.250ng/ml, 33.246ng/ml and 35.043ng/ml during the initial phase, lag phase and post lag phase of orthodontic treatment. The mean pro-inflammatory cytokine IL-17 A levels were 107.79pg/ml, 102.98pg/ml and 66.156pg/ml during the initial phase, lag phase and post lag phase of orthodontic treatment. There was a correlation between the salivary 1-25dihydroxycholecalciferol level and salivary cytokine IL-17A levels during the various phases of orthodontic treatment using Spearman's correlation rho test and linear regression analysis. There was no significant difference (p > 0.05) between 1-25dihydroxycholecalciferol levels and gender during the various phases (initial phase, lag phase and post lag phase) of Orthodontic treatment.There was a negative correlation between salivary 1-25dihydroxycholecalciferol level and salivary cytokine IL-17A levels during the various phases of orthodontic treatment. The level of 1-25dihydroxycholecalciferol and salivary cytokine IL-17A have been quantified during the various phases of Orthodontic treatment and this can be used clinically for the supplementation of Vitamin D in patients with low vitamin D levels and can enhance the treatment duration for the patient with less damaging effects to the surrounding tissues.