The effect of the extent of surgical insult on orthodontic tooth movement

Impact of micro-osteoperforations on root resorption and alveolar bone in en-masse retraction in young adults: A CBCT randomized controlled clinical trial

BACKGROUND

Micro-osteoperforations (MOPs) as a surgical technique is increasingly being used as a method to enhance orthodontic tooth movement. However, its iatrogenic effects on root and alveolar bone morphology have been less studied.

OBJECTIVE

This parallel-groups single-centered trial aimed to assess the impact of micro-osteoperforations (MOPs) on orthodontically induced inflammatory root resorption (OIIRR) and alveolar bone during en-masse retraction stage of maxillary and mandibular anterior teeth.

METHODS

Fifty-two patients (mean age 21.35±2.2 years) with Class I bi-dentoalveolar protrusion, requiring all 1st premolar extractions and miniscrews for anchorage, were randomly distributed into two groups (n=26 each): MOP group treated using single application of MOP's and control group treated with routine sliding mechanics, for en-masse retraction. The primary outcomes were assessed using CBCT-based measurements.

RESULTS

Anterior teeth in MOP group showed increased mean OIIRR than control group, though the difference was statistically non-significant [maxillary anteriors, MOP group - OIIRR=0.78±0.29mm and control group OIIRR=0.73±0.36mm; mandibular anteriors, MOP group - OIIRR=0.733±0.20mm and control group OIIRR=0.70±0.24mm]. Levander and Malmgren's Index for objective scoring of OIIRR revealed only mild resorption with most teeth in both the groups (47% and 51%, respectively). Lateral incisors showed highest OIIRR followed by central incisors and canines in both groups. Lingual side bone thickness and height decreased significantly, however, the differences between the two groups were non-significant (P>0.05).

CONCLUSION

Within the settings of the current RCT, en-masse retraction when combined with single application of micro-osteoperforations did not pose an increased risk of root resorption or alveolar bone changes compared to routine sliding mechanics.

The effect of platelet-rich concentrates on orthodontic tooth movement: A review of randomized controlled trials

Objectives

Platelet-rich concentrates, namely platelet-rich plasma (PRP) and platelet-rich fibrin (PRF), have recently shown potential roles in accelerating orthodontic tooth movement (OTM) and reducing treatment duration. Our study aims to systematically evaluate the effect of platelet-rich concentrates on OTM.

Materials and methods

An electronic search of 11 databases, followed by a hand search of reference lists of eligible studies and related reviews, was conducted up to January 2022. Randomized controlled trials investigating OTM of patients with platelet-rich concentrates were included. Risk of bias was assessed by version 2 of Cochrane tool (RoB 2) for assessing risk of bias in randomized trials.

Results

Among 715 records initially identified, 9 studies were included, of which 3 used PRP and the other 6 applied PRF. 7 studies supported a positive relationship between platelet-rich concentrates and OTM, but the other 2 studies reported a null and a negative effect of PRF, respectively. The overall qualities of evidence were moderate to high.

Conclusions

Platelet-rich concentrates as PRP and PRF seem to be effective in accelerating OTM at early stages, while their long-term efficacy remains controversial. Repeated application of platelet concentrates may increase the accelerated stability of OTM.

Effect of Extending Corticotomy Depth to Trabecular Bone on Accelerating Orthodontic Tooth Movement in Rats

Corticotomy is a surgical procedure that induces injury to the cortical bone to accelerate tooth movement. This study aimed to increase the depth of corticotomy to the trabecular bone and to evaluate the amount and rate of tooth movement and alveolar bone changes in response to various degrees of cortical and trabecular bone injury. Seventy-eight male Wistar rats were randomly divided into four groups based on procedure used: (1) baseline control group of orthodontic tooth movement (OTM) only; (2) OTM + 4 corticotomies (CO); (3) OTM + 4 osteotomies (OS); and (4) OTM + 16 CO. A closed-coil nickel–titanium spring was placed to move the maxillary first molar mesially with a 10 g force. On days 0, 7, 14, and 21, alveolar bone alteration and tooth movement were measured using microcomputed tomography. Significant tooth movement was related to the number and the depth of the perforations. The OTM + 16 CO group showed a greater amount and rate of tooth movement than the OTM + 4 CO group. When osteotomy and corticotomy were compared with the same volume of bone removed, the OTM + 4 OS group had a faster rate of tooth movement than the OTM + 16 CO group during the first week, with significantly reduced bone volume. However, no significant difference was observed in the amount of tooth movement between the OTM + 4 OS and OTM + 16 CO groups at the end of the study. Extending the depth of corticotomy to trabecular bone increased the amount of tooth movement by accelerating the induction and completion of bone remodeling, which accelerated the rate of tooth movement during the initial stage.

A sustained-release Trametinib bio-multifunction hydrogel inhibits orthodontically induced inflammatory root resorption

Orthodontic tooth movement (OTM) is a bone reconstruction process. In most cases, OTM could induce root resorption as a common side effect, called orthodontically induced inflammatory root resorption (OIIRR). OIIRR affects tooth health and interferes with the stability of orthodontic treatment. Osteoclasts, which perform bone resorption in OTM, attack cementum, causing OIIRR. Many signaling pathways are involved in the maturation and differentiation of osteoclasts, among which the ERK1/2 is one of the important pathways. In this experiment, we added Trametinib (Tra), a specific inhibitor of ERK1/2, to catechol-modified chitosan (CHI-C) and oxidized dextran (ODex) to form a CCOD-Trametinib composite hydrogel (CCOD-Tra) to prevent OIIRR. CCOD-Tra exhibited good biocompatibility, injectability, strong adhesion, good hemostatic function and sustained release of Tra. We performed local injection of CCOD-Tra into the periodontal tissues of rats. CCOD-Tra firmly adhered to the periodontal tissues and then released Tra to establish a good biological environment and maintain a drug concentration at a high level around the roots for a long time. H&E, TRAP, immunochemistry staining and micro-CT indicated that CCOD-Tra had a good effect in terms of preventing OIIRR. Cell experiments showed that CCOD-Tra reduced the expression of TRAP, MMP-9 and C-FOS in osteoclast cells through the ERK1/2 signaling pathway to inhibit the differentiation and maturation of osteoclasts. Based on the above results, we concluded that CCOD-Tra had the ability to prevent OIIRR, the high adhesion and injectability of CCOD may provide better therapeutic ideas for clinical prevention of OIIRR.

Effect of the Number of Micro-Osteoperforations on the Rate of Tooth Movement and Periodontal Response in Mice

Accelerated tooth movement can be achieved using micro-osteoperforations (MOPs) to stimulate regeneration of the alveolar bone during minimally invasive surgical trauma. However, there is currently no standardized protocol and limited reports regarding the side effects of MOPs based on biological evidence. This study sought to evaluate the biological effects of the number of MOPs on orthodontic tooth movement (OTM) and the potential risk for root resorption. Male CD1 mice were divided into 4 groups based on the number of MOPs, as follows: Sham; 0MOP+OTM; 2MOP+OTM; and 4MOP+OTM groups. Tooth movement distance and the number of osteoclasts were higher whereas bone volume and trabecular number were lower in the 4MOP+OTM group compared to those of the 0MOP+OTM group. Immunofluorescent assay analysis indicated that the 4MOP+OTM group was positively associated with rapid cementum regeneration and periodontal ligament tissue formation. Our findings revealed that the MOP procedure affected tooth movement and did not significantly contribute to root resorption, whereas it may promote constitutive activation of cementogenesis.

The effect of micro-osteoperforations on orthodontic space closure investigated over 12 weeks: a split-mouth, randomized controlled clinical trial

OBJECTIVES

To evaluate the effects of minimally invasive micro-osteoperforations (MOPs) on orthodontic tooth movement and pain.

DESIGN

Prospective, split-mouth, randomized controlled trial.

SETTING

Single-centre, university hospital.

METHODS

Twenty subjects requiring maxillary first premolar extractions were included. Right and left sides of the maxilla were randomly allocated into experimental and controls. Space closure was initiated following alignment on 0.20″ stainless steel archwires, using 150 g force, applied by coil springs on power arms. Nance-TPA was used for anchorage. On the experimental side, two 5 mm deep MOPs in vertical alignment on distal aspect of the maxillary canine mid-root region were performed prior to space closure.

OUTCOMES

The primary outcome was the amount of tooth movement during space closure, measured every 4 weeks for 12 weeks (T1, T2, and T3). Secondary outcome was the pain levels related to MOP, measured using Visual Analogue Scale (VAS) questionnaires. Significance was set at P < 0.01.

RANDOMIZATION

Randomization was generated using a randomization table, and allocation was concealed in sequentially numbered, opaque, sealed envelopes.

BLINDING

Blinding was not possible during the experiment but assessor was blinded during outcome assessment.

RESULTS

All subjects completed the study, with tooth movement measurements available for all 20 patients for T0-T2. In three patients, space was closed on one side at T2. The average tooth movement between sides at three intervals (T0-T1, T1-T2, and T2-T3) were not significantly different. Overall difference following 12 weeks (T0-T3) was 0.69 mm higher on the experimental side (P < 0.001). No harms were observed.

LIMITATIONS

Short-term study, cast measurements done with digital callipers.

CONCLUSION

This 12-week randomized split-mouth controlled clinical trial showed two MOPs that are 5 mm deep, applied once prior to space closure, did not create clinically significant increase in maxillary premolar space closure.

PROTOCOL

The protocol was not published before trial commencement.

REGISTRATION

Trial was not registered.

FUNDING

The Australian Society of Orthodontists Foundation for Research and Education.

The effect of differential force system and minimal surgical intervention on orthodontic tooth movement and root resorption

OBJECTIVE

The primary objective of this study was to quantify the orthodontic tooth movement (OTM) and orthodontically induced root resorption (OIRR) with differential force system in conjunction with minimal surgical insult.

MATERIAL AND METHODS

15-week-old, 48 male Wistar rats were used in the research and were randomly divided into six groups: 1. Group 1 (8 Wistar rats): OTM for 14 days with 8-g force; 2. Group 2 (8 Wistar rats): OTM for 14 days with 25-g force; 3. Group 3 (8 Wistar rats): OTM for 14 days with 100-g force; 4. Group 4 (8 Wistar rats): OTM for 14 days with 8-g force and alveolar decortications (ADs); 5. Group 5 (8 Wistar rats): OTM for 14 days with 25-g force and ADs; 6. Group 6 (8 Wistar rats): OTM for 14 days with 100-g force and ADs. A nickel-titanium spring was used to protract the molar mesially using maxillary incisors as an anchorage. ADs (minimal surgical insult) were done using a hand piece and a round bur, adjacent to the left first maxillary molar on the palatal alveolar bone. After 14 days of OTM, Wistar rats were killed and microfocus computed tomography and histological analysis were performed.

RESULTS

The 100-g group showed significant increase (P < 0.05) in OTM. However, with ADs, the OTM was significantly higher (P < 0.05) in 8 and 100 g. In addition, with ADs, there is significant increase (P < 0.05) in OIRR and significant decrease (P < 0.05) in bone volume fraction. Histological quantification of tartrate-resistant acid phosphatase indicated a significant increase (P < 0.05) in the number of osteoclasts with ADs when compared without ADs.

CONCLUSIONS

Light force in conjunction with ADs are optimal to accelerate the OTM. Additionally, ADs increases the OIRR.

Acceleration of orthodontic tooth movement and root resorption with near and distant surgical insults: An in-vivo study on a rat model

OBJECTIVE

The purpose of this study was to determine the effects of alveolar decortications (AD) closer and farther from the tooth on Orthodontic tooth movement (OTM) and root resorption.

MATERIALS AND METHODS

Twenty-four Wistar rats (age 17 weeks) were used in the study. Three groups were formed by randomly dividing the rats into: 1) Control Group (N=8): OTM (14 days) without any surgical insult; 2) Near Group (N=8) OTM (14 days)+Alveolar Decortications (AD) adjacent to roots of the maxillary first molar; 3) Far Group (N=8) OTM (14 days)+AD 5mm away from the roots of the maxillary first molar. OTM was performed using a closed coil Nickel-Titanium (NiTi) spring to apply a mesial force on maxillary first molars of 8-10 grams. AD was performed with high-speed quarter round bur on the palatal aspect of alveolar bone. The rats were euthanized after 2 weeks of OTM and microfocus computed tomography and histological analysis were performed.

RESULTS

Near-AD and Far-AD groups exhibited significantly increased OTM and reduction of Bone volume fraction compared to control. The root volume was significantly decreased (increased root resorption) in the Near-AD group. Histological analysis showed no statistically significant difference between the groups.

CONCLUSIONS

Alveolar decortications lead to a significant increase in the rate of OTM. Increased root resorption was observed when the alveolar decortications were performed close to the maxillary molar.

Efficacy and safety of different interventions to accelerate maxillary canine retraction following premolar extraction: A systematic review and network meta-analysis

Decreasing orthodontic treatment duration is at the forefront of innovation for clinical orthodontics. This network meta-analysis aimed to determine the relative efficacy and safety of treatments for accelerated orthodontic tooth movement (OTM) in patients undergoing extraction of maxillary first premolars followed by canine retraction in any orthodontic setting. MEDLINE, EMBASE, Cochrane CENTRAL, CINAHL and SCOPUS were searched (from inception to 20 April 2020). Study selection and data extraction were performed in duplicate. Eligible randomized controlled trials (RCTs) were meta-analysed to estimate the rate of tooth movement, 95% credible interval and surface under the cumulative ranking curve (SUCRA) in the first 3 months following the application of the adjunctive accelerative method. Eligible RCTs were assessed by Cochrane risk of bias tool, and quality of evidence was assessed by GRADE approach, obtained from CINeMA web application. Interventions were ranked for efficacy and reviewed for safety. Nineteen studies pertaining to eight interventions, with data from 415 patients were included. Quality of evidence was very low to moderate. Very low-to low-quality evidence suggests that corticotomy is an efficacious and safe adjunctive treatment to accelerate OTM in comparison with conventional treatment in the first 2 months of treatment. Low-quality evidence suggests that piezocision and micro-osteoperforations (MOP) are efficacious and safe adjunctive treatments only in the first month of treatment. Frequent MOP in conjunction with low-level laser therapy appeared to be an efficacious and safe adjunctive treatment only in the first month following its initial application but not thereafter.

Comparison of the efficacy of two-time versus one-time micro-osteoperforation on maxillary canine retraction in orthodontic patients: A split-mouth randomized controlled clinical trial

BACKGROUND

Micro-osteoperforation (MOP), a minimally invasive technique for accelerating the rate of orthodontic tooth movement has been research extensively, but with varied clinical results.

OBJECTIVE

To compare the efficacy of one-time versus two-time micro-osteoperforation on the rate of maxillary canine retraction, its influence on anchorage loss, canine angulation and the levels of interleukin (IL-1β) in gingival crevicular fluid (GCF).

MATERIALS AND METHODS

The split-mouth study included 16 patients in which the left and right sides were randomly allocated to the control side (one-time MOP) and experimental side (two-time MOP). MOP was performed on both sides distal to the maxillary canines and canine retraction was carried out using NiTi closed coil springs (150gm) and direct anchorage with miniscrew implants. The second MOP was performed on experimental side one month after the first MOP. The rate of canine movement was assessed using 3D model superimposition over a period of six months. The type of tooth movement, anchorage loss and levels of IL-1β were also evaluated.

RESULTS

Sixteen patients (mean age, 17.87±3.34 years) were analysed for a rate of canine retraction, anchorage loss, and type of tooth movement, while 15 patients were analysed for IL-1β. The rate was significantly higher on two-time MOP side after two months (P<0.001). No statistical difference was found in anchorage loss and controlled tipping of canines was observed. The IL-1β levels immediately after 2^nd MOP were significantly higher than 1^st MOP (P<0.001).

CONCLUSION

The two-time intervention of MOP is more efficacious than one-time MOP in accelerating tooth movement.

The effectiveness of locally injected platelet-rich plasma on orthodontic tooth movement acceleration

OBJECTIVES

To critically appraise the current evidence available from animal studies pertaining to the effectiveness of platelet-rich plasma (PRP) in accelerating orthodontic tooth movement.

MATERIALS AND METHODS

Electronic searches of nine databases were conducted up to June 2020, followed by a hand search of the reference list of eligible studies. The study design required was prospective controlled animal studies. The primary outcome assessed was the rate of orthodontic tooth movement. The secondary outcome evaluated was histological changes after PRP application. Following study retrieval and selection, relevant data were extracted. Risk-of-bias (RoB) assessment was done using the Systematic Review Center for Laboratory Animal Experimentation's Risk of Bias Tool (SYRCLE's Risk of Bias Tool). Two review authors conducted the work of searching, study selection, and quality assessment independently and in duplicate.

RESULTS

Of 193 studies, 5 animal studies were included in this systematic review. Three studies found a positive correlation between PRP injection and tooth movement acceleration, along with corresponding histological changes. Two studies detected no significant difference in tooth movement rate after PRP application.

CONCLUSIONS

Based on the current limited evidence, the efficacy of PRP on tooth movement acceleration remains debatable. More well-designed randomized controlled trials involving humans are called for to obtain more clinically significant conclusions.

Evaluation of the effects of diode laser application on experimental orthodontic tooth movements in rats. Histopathological analysis

Purpose:

To evaluate the effect of diode laser use on experimental orthodontic tooth movements.

Methods:

Thirty Rattus norvegicus albinus Wistar were divided into three equal groups (n = 10), two experimentals and one control. Applying 20 g orthodontic force were attached to the maxillary incisors of the rats in all groups. Low dose laser was applied to the surrounding tissues of the maxillary incisors of the rats in the experimental groups. Two exposure times for laser irradiation were used for seven days: t = 12 min (energy dose = 72 J) and t = 9 min (energy dose = 54 J) by a 0.1 W DEKA brand diode laser with wavelength of 980 nm.

Results:

Osteoclastic activation increased in the 72 J group when compared to control group and decreased in comparison to the 54 J group. Osteoblastic activation was decreased in the 72 J group when compared to the control group and increased in comparison to the 54 J group.

Conclusions:

Applying 54 J laser energy has been found effective to accelerate the orthodontic tooth movement.

Simplifying the approach of open bite treatment with aligners and selective micro-osteoperforations: An adult case report

INTRODUCTION

Open bite treatment represents one of the most challenging malocclusions because it has a multifactorial aetiology and in particular because its dental correction strongly depends on the possibility to manage the posterior intrusion with a reliable system controlling the vertical position of upper and lower molars. Clear Aligner system proved to be an efficient way to control the hyper divergent patients performing posterior intrusion and managing the counterclockwise rotation of the mandible. This technique has shown to be predictable for molar intrusion up to 1mm.

METHODS

This case report shows a successful open bite orthodontic treatment in which the molar intrusion effect has been amplified in the digital setup and facilitated by means of micro-osteo perforations (MOPs) performed selectively only in the molar areas in order to stimulate the bone in a specific movement direction. The digital setup was set to create molar intrusion in upper and lower molars up to 3mm and thus favouring a counterclockwise mandible rotation, supported and controlled by elastics. The posterior intrusion was combined with an anterior extrusion following smile arc exposure and the treatment was completed in 16 months overall.

RESULTS

The final cephalometric analysis showed a significant reduction of SN/Go-Gn angle of 4° with consequent counterclockwise rotation of the mandible. The mandibular superimposition showed a 2.5mm molar intrusion without root resorption and with a controlled incisor proclination. A solid Class I bilateral occlusion was achieved with normal overjet and overbite, the dental arches were well aligned and levelled with good intra-arch symmetry and regular arch form. The frontal aesthetic analysis showed an improvement of the dental exposure with a normalized smile arc due to a combination of relative and pure extrusion.

CONCLUSION

The present alternative approach to treat severe open bite combining selective MOPs in the posterior and lateral sectors and clear aligners could predictably control molar vertical position avoiding the use of auxiliary and eliminating the risk of root resorption. Arch development, molar intrusion, and overbite correction with counterclockwise mandible rotation could be predictably achieved respecting digital setup and creating proper Class I bilateral occlusion.

The effects of mandibular osteotomy on maxillary orthodontic tooth movement and bone remodelling in a rat model

OBJECTIVES

The accelerated tooth movement phenomenon after orthognathic surgery has been observed. However, the underlying mechanism remains unclear. There is no experimental study showing the effect of orthognathic surgery on orthodontic tooth movement of the opposing jaw. Therefore, the present study aimed at investigating if mandibular osteotomy enhances maxillary tooth movement and bone remodelling.

MATERIALS AND METHODS

Fifty-four male Sprague-Dawley rats were randomly divided into two groups: maxillary tooth movement (TM) and maxillary tooth movement + mandibular surgery (TM + MS). The orthodontic force was delivered to move the left maxillary first molar mesially. The surgical intervention was performed on the left mandible. Microcomputed tomography, histological analysis, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction were used to assess changes at 3, 7, and 21 days after surgery.

RESULTS

The mandibular osteotomy accelerates the rate of maxillary tooth movement with decreased bone volume fraction on the seventh day. Bone resorption was observed on the third and seventh day after mandibular osteotomy. It was found that serum interleukin-1β level increased significantly in the TM + MS group compared with the TM group, as well as the high expression level of cathepsin K and tumour necrosis factor receptor-associated factor 5 of the orthodontic tooth on the third and seventh day after mandibular osteotomy.

CONCLUSION

Data from the present study suggested that mandibular osteotomy accelerates maxillary osteoclast activity and post-operative tooth movement, providing evidence for accelerated tooth movement phenomenon after orthognathic surgery.

The effect of alveolar decortication on orthodontically induced root resorption

OBJECTIVE

To determine the effect of alveolar decortication on orthodontically induced root resorption.

MATERIALS AND METHODS

A total of 24 male Wistar rats (14 week old) were used. The rats were randomly divided into one of the following three groups: group 1 (control group), orthodontic tooth movement (OTM) for 2 weeks; group 2, OTM for 2 weeks + two alveolar decortications (2AD); group 3, OTM for 2 weeks + four alveolar decortications (4AD). The first molar was moved mesially for 2 weeks. Micro computed tomography was used to analyze root volume. In addition, histological sections were stained with Tartrate Resistant Acid Phosphatase (TRAP) to quantify the osteoclast number.

RESULTS

The buccal root volume in OTM + 4AD group was decreased by 8.92% and 6.11% when compared with the OTM-only group and OTM + 2AD group, respectively. Similarly, the other four root volumes in the OTM + 4AD group was decreased by 8.99% and 5.24% when compared with the OTM-only group and OTM + 2AD group, respectively. There was a decrease in buccal root density in the OTM + 4AD group by 4.66% and 3.56% when compared with the OTM-only group and the OTM + 2AD group, respectively. In addition, there was an increase in the number of osteoclasts by 195.73% and 98.74% in OTM + 4AD group in comparison with the OTM and OTM + 2AD group.

CONCLUSIONS

The amount of orthodontically induced root resorption was positively correlated with the extent of surgical injury used to accelerate orthodontic tooth movement.

Dentoalveolar Distraction Osteogenesis for Rapid Maxillary Canine Retraction: An Overview of Technique, Treatment, and Outcomes

Patients and orthodontists seek to reduce treatment time in braces. Rapid canine retraction through dentoalveolar distraction osteogenesis is one of several treatment approaches to reduce treatment in braces. This article provides an overview of technique of dentoalveolar distraction osteogenesis to accomplish rapid canine retraction and associated outcomes. When this treatment protocol is implemented well, rapid canine retraction is achieved predictably with minimal side effects. Although current evidence suggests that adverse sequelae, such as root resorptions and pulp devitalization, are rare, prospective clinical studies that are adequately powered and documenting long-term follow-up of these outcomes are lacking.