Corticotomy-Assisted Orthodontic Enhancement by Bone Morphogenetic Protein-2 Administration

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

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

Effect of light-emitting photobiomodulation therapy on the rate of orthodontic tooth movement : A randomized controlled clinical trial

PURPOSE

The aim of this study was to evaluate the effect of light-emitting photobiomodulation therapy (LPT) on the rate of canine distalization.

METHODS

This study was performed on 60 extraction spaces formed by extraction of the upper first premolars of 30 patients (15 in the LPT group and 15 in the control group). Paul Gjessing (PG)-segmented canine retraction springs were used for canine distalization. In the LPT group, the Biolux OrthoPulse™ (Biolux Research Ltd, Vancouver, Canada) intraoral device (wavelength 850 nm LED light and an energy density of 63 mW/cm2 [±13 mW/cm2]) was used for 5 min per day over a period of 84 days. For each patient, the diagnosis was based on standard orthodontic documentation with photographs, digital model casts, and cephalometric and panoramic radiographs. The anchorage loss, canine rotations, canine inclinations, and molar inclinations were also evaluated on plaster models obtained on days 0, 21, 42, 63, and 84. The models were measured by using 3Shape OrthoAnalyzer software (3Shape, Copenhagen, Denmark). Measurements were made by a researcher and a blinded clinician. For statistical comparison, a paired-samples t‑test and one-way analysis of variance (ANOVA) were used at the p < 0.05 level.

RESULTS

The mean canine distalization rates were 1.36 mm/21 days and 1.02 mm/21 days in the LPT and control groups, respectively, and were statistically greater in the LPT group (p < 0.001). The amount of anchorage loss, canine rotations, canine inclinations and molar inclinations were not significantly different between the LPT and control groups at any of the timepoints.

CONCLUSION

LPT has the potential to accelerate orthodontic tooth movement by 33%.

Effect of local application of bone morphogenetic protein -2 on experimental tooth movement and biological remodeling in rats

Background: This study attempts to detect the potential effects of local bone morphogenetic protein -2 (BMP-2) on orthodontic tooth movement and periodontal tissue remodeling. Methods: Forty adult SD rats were randomly divided into four groups: blank control group, unilateral injection of BMP-2 on the pressure side or tension side of orthodontic teeth and bilateral injection of BMP-2. Their maxillary first molar was moved by a 30 g constant force closed coil spring. 60 μL of BMP-2 with a concentration of 0.5 μg/mL was injected into each part at a time. In addition, three rats were selected as healthy control rats without any intervention. Fluorescent labeled BMP-2 was used to observe the distribution of exogenous BMP-2 in tissues. Micro-CT was used to measure the microscopic parameters of tooth displacement, trabecular bone and root absorption volume. Three different histological methods were used to observe the changes of tissue remodeling, and then the number of osteoclasts and the content of collagen fibers were calculated. Results: Compared with the blank control group, BMP-2 injection reduced the movement distance and increased the collagen fiber content and bone mass (p < 0.01). There was no significant difference in tooth movement distance, BV/TV ratio and BMD between injection sites in unilateral injection group (p > 0.05). In the case of bilateral injection of BMP-2, the osteogenesis is enhanced. Unilateral injection of BMP-2 did not promote root resorption, but double injection showed root resorption (p < 0.01). Conclusion: Our study does show that the osteogenesis of BMP-2 is dose-dependent rather than site-dependent when a certain amount of BMP-2 is applied around orthodontic teeth. Local application of BMP-2 around orthodontic teeth in an appropriate way can enhance bone mass and tooth anchorage without increasing the risk of root absorption volume. However, high levels of BMP-2 may cause aggressive root resorption. These findings are of great significance, that is, BMP-2 is an effective target for regulating orthodontic tooth movement.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Mechanistic Insight into Orthodontic Tooth Movement Based on Animal Studies: A Critical Review

Alveolar bone remodeling in orthodontic tooth movement (OTM) is a highly regulated process that coordinates bone resorption by osteoclasts and new bone formation by osteoblasts. Mechanisms involved in OTM include mechano-sensing, sterile inflammation-mediated osteoclastogenesis on the compression side and tensile force-induced osteogenesis on the tension side. Several intracellular signaling pathways and mechanosensors including the cilia and ion channels transduce mechanical force into biochemical signals that stimulate formation of osteoclasts or osteoblasts. To date, many studies were performed in vitro or using human gingival crevicular fluid samples. Thus, the use of transgenic animals is very helpful in examining a cause and effect relationship. Key cell types that participate in mediating the response to OTM include periodontal ligament fibroblasts, mesenchymal stem cells, osteoblasts, osteocytes, and osteoclasts. Intercellular signals that stimulate cellular processes needed for orthodontic tooth movement include receptor activator of nuclear factor-κB ligand (RANKL), tumor necrosis factor-α (TNF-α), dickkopf Wnt signaling pathway inhibitor 1 (DKK1), sclerostin, transforming growth factor beta (TGF-β), and bone morphogenetic proteins (BMPs). In this review, we critically summarize the current OTM studies using transgenic animal models in order to provide mechanistic insight into the cellular events and the molecular regulation of OTM.

Automated tooth segmentation as an innovative tool to assess 3D-tooth movement and root resorption in rodents

BACKGROUND

Orthodontic root resorptions are frequently investigated in small animals, and micro-computed tomography (μCT) enables volumetric comparison. Despite, due to overlapping histograms from dentine and bone, accurate quantification of root resorption is challenging. The present study aims at (i) validating a novel automated approach for tooth segmentation (ATS), (ii) to indicate that matching of contralateral teeth is eligible to assess orthodontic tooth movement (OTM) and root resorption (RR), (iii) and to apply the novel approach in an animal trial performing orthodontic tooth movement.

METHODS

The oral apparatus of three female mice were scanned with a μCT. The first molars of each jaw and animal were segmented using ATS (test) and manually (control), and contralateral volumes were compared. Agreement in root volumes and time efficiency were assessed for method validation. In another n = 14 animals, the left first upper molar was protracted for 11 days at 0.5 N, whereas the contralateral molar served as control. Following ATS, OTM and RR were estimated.

RESULTS

ATS was significantly more time efficient compared to the manual approach (81% faster, P < 0.01), accurate (volume differences: - 0.01 ± 0.04 mm³), and contralateral roots had comparable volumes. Protracted molars had significantly lower root volumes (P = 0.03), whereas the amount of OTM failed to reveal linear association with RR (P > 0.05).

CONCLUSIONS

Within the limits of the study, it was demonstrated that the combination of ATS and registration of contralateral jaws enables measurements of OTS and associated RR in μCT scans.

Applications of Bone Morphogenetic Proteins in Dentistry: A Bibliometric Analysis

Background

Many articles on bone morphogenetic proteins (BMPs) have been published. Bibliometric analysis is helpful to determine the most influential studies in a specific field. This bibliometric analysis is aimed at identifying and analyzing the top 50 most-cited articles on the dental applications of BMPs.

Methods

An electronic search was conducted using the Web of Science (WoS) “All Databases” without any restriction of language, study design, or publication year. Of 1341 publications, the top 50 were included based on their citation count. After downloading the full texts, their bibliometric data including publication title, authorship, citation count, current citation index 2019, citation density, year of publication, country and institution of origin, journal of publication, type of BMP, study design, evidence level of publication, and keywords were extracted and analyzed.

Results

The citation counts for the top 50 publications ranged from 81 to 557 (median 113.5). The most prolific year was 1997 (n = 7). Wikesjö UM (n = 12) and Wozney JM (n = 11) were the major contributors in this study. Most of the articles were generated primarily from the USA (n = 24), with Loma Linda University Medical Center, USA being the most prolific institution (n = 5). Majority of the articles were published in the Clinical Oral Implants Research and Journal of Periodontology, with nine publications each. Most of the publications were animal studies (n = 30) and focused on BMP-2 (n = 39). Most of the articles were within evidence level V (n = 36). The most frequently used keyword in the top articles was “bone regeneration” (n = 23).

Conclusion

The present study presents insights into the past and recent trends in the applications of BMPs in dentistry. A statistically significant association was observed between citation count, citation density, and age of publication.

Remote Corticotomy Accelerates Orthodontic Tooth Movement in a Rat Model

Introduction

With an increasing demand for orthodontic treatment for adult patients, orthodontic professionals are constantly seeking novel strategies and technologies that can accelerate tooth movement in order to shorten the treatment period. For instance, in recent years, the influences of different surgical techniques on orthodontic tooth movement in the ipsilateral side of surgery were intensively investigated. Here, we attempt to examine if corticotomy could also affect the rate of tooth movement in the contralateral side of the surgery by using a rodent model.

Materials and Methods

72 eight-week-old Sprague-Dawley rats were randomly divided into three groups as follows: the Control group (orthodontic treatment devices delivered only, no tooth movement), the orthodontic tooth movement (OTM) group (orthodontic treatment devices delivered and orthodontic treatment performed), and the Corticotomy + OTM group (remote corticotomy performed, orthodontic treatment devices delivered, followed by orthodontic treatment). The surgical procedure was conducted on the right side of the maxilla at the time of appliance placement and a force of 60 g was applied between the maxillary left first molar and maxillary incisors using nickel-titanium springs to stimulate OTM. The OTM distance and speed were tracked at 3, 7, 14, and 28 days post-surgery, followed by histological and immunohistochemical assessments.

Results

In comparison with orthodontic treatment only, the contralateral corticotomy significantly accelerated OTM. Furthermore, animals undergoing corticotomy + OTM presented with a greater number of osteoclasts on the compression side, stronger staining of the osteogenic marker on the tension side, and higher expression of an inflammatory marker than the OTM group animals.

Conclusion

Our current study demonstrates that remote corticotomy effectively accelerates alveolar bone remodeling and OTM. The study enriches our understanding of the regional acceleratory phenomenon (RAP) and offers an alternative strategy for accelerating OTM to shorten the orthodontic treatment period.

The effects of NELL on corticotomy-assisted tooth movement and osteogenesis in a rat model

INTRODUCTION

Exogenous Nel-like molecule type 1 (NELL1) represents a potentially attractive clinical treatment option in the orthodontic and other settings because of its osteoinductive and vasculogenic properties.

AIMS

To explore effects of NELL1on corticotomy-assisted tooth movement and osteogenesis in a rat model.

METHODS

Thirty Sprague-Dawley rats were divided into 6 groups: Control, Sham, Tooth movement only, Vehicle, NELL1-LD (low-dose NELL), NELL1-HD (high-dose NELL). Human recombinant NELL1 protein was applied locally (Groups NELL1-LD and NELL1-HD) into buccal mucosa region of left first upper molar. Then the distance and velocity of tooth movement was measured, animals at 6 weeks after surgery were sacrificed, and was followed by computed tomography and histochemical staining.

RESULTS

Both NELL1 groups had higher bone mineral density, greater tooth movement distance and velocity in comparison to the Vehicle group. Proximally and distally, periodontal ligament width was significantly increased in the NELL1-LD and NELL1-HD groups. Decortication enhances remodeling, however, rapid bone formation by high-dose NELL1 may affect bone absorption.

CONCLUSION

Appropriate dose of NELL1 can be administrated to reduce the total time for tooth movement, and may shorten the treatment time in select populations.

Periodontally accelerated osteogenic orthodontics combined with recombinant human bone morphogenetic protein-2: An outcome assessment

Context:

Periodontally accelerated osteogenic orthodontics (PAOO) combines alveolar corticotomy, bone graft materials, and the application of orthodontic forces for rapid correction of malocclusions.

Aims:

The present study aims to primarily assess differences in orthodontic treatment duration, bone quality around corticotomy sites, postoperative healing, and subjective pain when corticotomy was done conventionally and with the placement of recombinant human bone morphogenetic protein-2 (rhBMP-2).

Settings and Design:

Thirty individuals participated in this study. Individuals were randomly assigned into each of the following experimental groups; C + BMP: Corticotomy with 0.5 μg/mL rhBMP-2 and C: Corticotomy only.

Materials and Methods:

Clinical parameters included recording the duration of the treatment period, visual analog scale scores and early wound healing index scores. The evaluation of bone density was performed at baseline, 3 months, and 6 months by using RVG.

Statistical Analysis Used:

Two-way analysis of variance and post hoc multiple comparison tests were used to compare data between test and control groups at different time points.

Results:

rhBMP-2 application was effective in reducing the overall treatment time and resulted in an increase in bone density around corticotomy sites at the end of the treatment period when compared to conventional corticotomy procedure. Placement of rhBMP-2 neither delayed wound healing nor affected participant pain scores.

Conclusions:

From this trial conducted over a period of 6 months, rhBMP-2 has the potential to function as a regenerative material in PAOO.

Ability of mini-implant-facilitated micro-osteoperforations to accelerate tooth movement in rats

INTRODUCTION

Although current techniques for accelerated tooth movement often involve invasive surgical procedures, micro-osteoperforations (MOPs) using mini-implants may facilitate orthodontic tooth movement without raising flaps, reduce surgical risks, and increase patient acceptance. In this study, we evaluated the effectiveness of mini-implant-facilitated MOPs in inducing accelerated tooth movement and investigated the potential risks for root resorption.

METHODS

Five MOPs were placed on the left side around the maxillary first molars in 6 rats using an automated mini-implant driver, whereas the right side received no MOPs as the control. Closed-coiled springs were secured from incisors to first molars for orthodontic tooth movement. Tooth movement was measured, and samples underwent radiologic and histologic analyses.

RESULTS

The MOP side exhibited a 1.86-fold increase in the rate of tooth movement with decreased bone density and bone volume around the first molars compared with the control side. Hematoxylin and eosin and tartrate-resistant acid phosphatase analyses showed increased numbers of osteoclasts as well as new bone formation. Three-dimensional volumetric analysis of all 5 roots of the maxillary first molars demonstrated no statistically significant difference in root volumes.

CONCLUSIONS

Mini-implant-facilitated MOPs accelerated tooth movement without increased risk for root resorption and therefore may become a readily available and efficient treatment option to shorten orthodontic treatment time with improved patient acceptance.

Gene Therapy for Bone Defects in Oral and Maxillofacial Surgery: A Systematic Review and Meta-Analysis of Animal Studies

Craniofacial bone defects are challenging problems for maxillofacial surgeons over the years. With the development of cell and molecular biology, gene therapy is a breaking new technology with the aim of regenerating tissues by acting as a delivery system for therapeutic genes in the craniofacial region rather than treating genetic disorders. A systematic review was conducted summarizing the articles reporting gene therapy in maxillofacial surgery to answer the question: Was gene therapy successfully applied to regenerate bone in the maxillofacial region? Electronic searching of online databases was performed in addition to hand searching of the references of included articles. No language or time restrictions were enforced. Meta-analysis was done to assess significant bone formation after delivery of gene material in the surgically induced maxillofacial defects. The search identified 2081 articles, of which 57 were included with 1726 animals. Bone morphogenetic proteins were commonly used proteins for gene therapy. Viral vectors were the universally used vectors. Sprague-Dawley rats were the frequently used animal model in experimental studies. The quality of the articles ranged from excellent to average. Meta-analysis results performed on 21 articles showed that defects favored bone formation by gene therapy. Funnel plot showed symmetry with the absence of publication bias. Gene therapy is on the top list of innovative strategies that developed in the last 10 years with the hope of developing a simple chair-side protocol in the near future, combining improvement of gene delivery as well as knowledge of the molecular basis of oral and maxillofacial structures.

Surgically facilitated experimental movement of teeth: systematic review

Several surgical techniques based on corticotomy and dental distraction have been developed to improve the movement of teeth and reduce the duration of orthodontic treatment. In this systematic review we have critically assessed published studies on the experimental movement of teeth to find out whether operations such as corticotomy and dental distraction osteogenesis increase the rate of movement, and to find out which biological mechanisms are engaged during surgically facilitated orthodontics, and which complications may be seen. We searched PubMed and Embase for publications until January 2014 and screened the titles and abstracts. Articles that met the inclusion criteria were retrieved in full and assessed independently by 2 of the authors. A total of 22 studies were included, and corticotomy and distraction techniques were the main surgical methods. Generally, all studies reported that movement of teeth was faster after operation than with conventional orthodontics. The peak velocity was always at an early postoperative stage regardless of the surgical technique used. Immunohistological data showed simultaneous regional increases in catabolic and anabolic activity. Histomorphometric data showed more direct resorption of bone and less hyalinisation after operation, and a reduced bone volume density around the surgical site. When present, complications such as root resorption or periodontal problems were minimal. Current experimental animal studies show that procedures such as corticotomy and dental distraction can accelerate the movement of teeth without severe complications because of the regional increase in catabolic and anabolic remodelling.

Surgical assistance for rapid orthodontic treatment and temporary skeletal anchorage

In surgically-assisted osteogenic orthodontics, multiple modalities are combined to shorten treatment time and to accomplish results that cannot be achieved with orthodontics alone. There is a significant reduction in cost to the patient, especially when there is a lack of insurance coverage for orthognathic techniques. Surgeons are able to work in the comfortable environment of their own offices. Decreased cost, recovery time, and treatment time, and an in-office environment all increase patient acceptance and allow surgeons to provide treatment to patients who might otherwise have no options.

Surgically facilitated orthodontic treatment: a systematic review

INTRODUCTION

Corticotomy and dental distraction have been proposed as effective and safe methods to shorten orthodontic treatment duration in adolescent and adult patients. A systematic review was performed to evaluate the evidence supporting these claims.

METHODS

PubMed, Embase, and Cochrane databases were searched until April 2013 for randomized controlled trials, controlled clinical trials, and case series with 5 or more subjects that focused on velocity of tooth movement, reduction of treatment duration, or complications with various surgical protocols. There were no language restrictions during the search phase. Publications were systematically assessed for eligibility, and 2 observers graded the methodologic quality of the included studies with a predefined scoring system.

RESULTS

Eighteen articles met the inclusion criteria. Seven studies were clinical trials, with small investigated groups. Only studies of moderate and low values of evidence were found. Surgically facilitated treatment was indicated for various clinical problems. All publications reported temporarily accelerated tooth movement after surgery. No deleterious effects on the periodontium, no vitality loss, and no severe root resorption were found in any studies. However, the level of evidence to support these findings is limited owing to shortcomings in research methodologies and small treated groups. No research concerning long-term stability could be included.

CONCLUSIONS

Evidence based on the currently available studies of low-to-moderate quality showed that surgically facilitated orthodontics seems to be safe for the oral tissues and is characterized by a temporary phase of accelerated tooth movement. This can effectively shorten the duration of orthodontic treatment. However, to date, no prospective studies have compared overall treatment time and treatment outcome with those of a control group. Well-conducted, prospective research is still needed to draw valid conclusions.

Current Approaches of Bone Morphogenetic Proteins in Dentistry

Bone morphogenic proteins (BMPs) are a group of osteoinductive proteins obtained from nonmineralized bone matrix; they are capable of stimulating the differentiation of pluripotent mesenchymal cells to osteoprogenitor cells. They have become a likely treatment option, given their action on regeneration and remodeling of bone lesions and increasing the bone response around alloplastic materials. It may be feasible in the near future for BMPs to replace autologous and allogenic bone grafts. The application of specific growth factors for osteoinduction without using a bone graft constitutes a real impact on bone regeneration. The use of BMP is not only focused on osteogenic regeneration: There are a variety of studies investigating other properties, such as periodontal or dental regeneration from the conservative viewpoint. In this review, we will highlight the role of the BMP in bone, periodontal and dental regeneration.

Photobiomodulation accelerates orthodontic alignment in the early phase of treatment

Background

Numerous strategies have been proposed to decrease the treatment time a patient requires in orthodontic treatment. Recently, a number of device-accelerated therapies have emerged in orthodontics. Photobiomodulation is an emerging area of science that has clinical applications in a number of human biological processes. The aim of this study was to determine if photobiomodulation reduces the treatment time in the alignment phase of orthodontic treatment.

Methods

This multicenter clinical trial was performed on 90 subjects (73 test subjects and 17 controls), and Little's Index of Irregularity (LII) was used as a measure of the rate of change of tooth movement. Subjects requiring orthodontic treatment were recruited into the study, and the LII was measured at regular time intervals. Test subjects used a device which produced near-infrared light with a continuous 850-nm wavelength. The surface of the cheek was irradiated with a power density of 60 mW/cm² for 20 or 30 min/day or 60 min/week to achieve total energy densities of 72, 108, or 216 J/cm², respectively. All subjects were fitted with traditional orthodontic brackets and wires. The wire sequences for each site were standardized to an initial round alignment wire (014 NiTi or 016 NiTi) and then advanced through a progression of stiffer arch wires unit alignment occurred (LII < 1 mm).

Results

The mean LII scores at the start of the clinical trial for the test and control groups were 6.35 and 5.04 mm, respectively. Multi-level mixed effect regression analysis was performed on the data, and the mean rate of change in LII was 0.49 and 1.12 mm/week for the control and test groups, respectively.

Conclusions

Photobiomodulation produced clinically significant changes in the rates of tooth movement as compared to the control group during the alignment phase of orthodontic treatment.