Multilevel biological responses following piezocision to accelerate orthodontic tooth movement: A study in rats

Biomodulation of Induced Tooth Movement by Three Methods, Corticopuncture, Photobiomodulation, and Their Combination: An Animal Study

Objective: The aim of this study was to assess the effects of accelerated tooth movement (ATM) methods: corticopuncture (CP), photobiomodulation (PBM), and their combination (CP + PBM) by evaluating tooth displacement, alveolar bone changes, and molecular and cellular response compared with conventional induced tooth movement. Materials and methods: Tooth movement and bone changes were evaluated on days 1, 3, and 7 (9 animals per time point) using microtomography, histological, and immunohistochemical evaluation, at compression and tension sites. CP groups received two perforations in the palate and one mesial to the molars. PBM was performed using GaAlAs diode laser applied every other day for 7 days (λ = 808 nm, 100 mW) in two points for 15 sec/point and total energy of 3 J. Results: Tooth movement was significantly increased in all three ATM groups after 7 days compared with the control group (mean 0.24 mm) by 27% PBM (0.31 mm), 45% CP (0.35 mm), and 57% CP + PBM (0.38 mm) (p < 0.05). At the compression side, all ATM groups showed significant decrease in bone density on day 3 (p < 0.05) and significant less bone volume on day 7 compared with Control (p < 0.05). At the tension side, PBM group showed a significant increase in bone density and volume on day 3 (p < 0.05). Immunohistochemistry analysis showed that at the compression side, tartrate-resistant acid phosphatase-positive cells, RANKL, and tumor necrosis factor-alpha expression were highly marked of the PBM and the combined method groups (p < 0.05). PBM and CP + PBM groups showed a significant increase in expression Runt-related transcription factor 2 and osterix (p < 0.05) at the tension side. Conclusions: All ATM groups showed increase on tooth displacement with CP + PBM group showing greatest tooth displacement. CP method appears to stimulate bone catabolism, PBM has more effect on bone formation, and the combined method showing a synergistic effect on bone remodeling.

Monitoring orthodontic tooth movement in rats after piezocision by bone scintigraphy

AIM

Piezocision, corticocision of mineralized tissue by ultrasound showed promising results in accelerating tooth movement induced by orthodontic appliances although the biologic effects of this procedure are not well-understood so far. The aim of this study was to investigate the impact of piezocision on bone remodeling in rats by bone SPECT imaging.

MATERIAL AND METHODS

Ten male Wistar rats underwent surgical placement of orthodontic appliances on each side of the maxilla followed by piezocision on one side only. Each rat underwent ^99mTc-MDP bone SPECT/CT imaging before surgery (T0), and 2 (T1) and 4 weeks (T2) after surgery. Bone uptake is expressed as median [IQR] min-max in percentage of the injected activity per ml computed from the 10 voxels with the highest uptake (%IAmax10/ml).

RESULTS

Pooled data regardless of the piezocision showed a significant increase in bone uptake from T0 (3.2 [2.8-3.9] 2.6-4.9) to T1 (4.4 [3.8-4.6] 3.4-4.8; p = 0.001). Thereafter, the uptake decreased to T2 (3.8 [3.1-4.4] 2.8-4.8; p = 0.116). No significant differences in bone uptake were found between the maxilla sides without and with piezocision: T1: without (4.3 [3.8-4.5] 3.4-4.8) vs. with (4.5 [3.7-4.6] 3.5-4.7; p=0.285), T2: without (4.0 [3.1-4.5] 2.8-4.8) vs. with (3.7 [3.0-4.4] 2.8-4.8; p=0.062).

CONCLUSION

^99mTc-MDP bone SPECT imaging in rats was able to reproduce changes in bone uptake in the maxilla after placement of orthodontic appliances inducing measurable tooth movement. An additional effect of piezocision on bone remodeling in terms of bone uptake was not detectable which is probably due to the pronounced and significant effects induced by the orthodontic appliances per se, which may mask the potential effects of additional piezocision.

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.

Accelerated orthodontic tooth movement: surgical techniques and the regional acceleratory phenomenon

BACKGROUND

Techniques to accelerate tooth movement have been a topic of interest in orthodontics over the past decade. As orthodontic treatment time is linked to potential detrimental effects, such as increased decalcification, dental caries, root resorption, and gingival inflammation, the possibility of reducing treatment time in orthodontics may provide multiple benefits to the patient. Another reason for the surge in interest in accelerated tooth movement has been the increased interest in adult orthodontics.

REVIEW

This review summarizes the different methods for surgical acceleration of orthodontic tooth movement. It also describes the advantages and limitations of these techniques, including guidance for future investigations.

CONCLUSIONS

Optimization of the described techniques is still required, but some of the techniques appear to offer the potential for accelerating orthodontic tooth movement and improving outcomes in well-selected cases.

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.

Comparison between conventional and piezocision-assisted orthodontics in relieving anterior crowding: a systematic review and meta-analysis

BACKGROUND

Prolonged duration of orthodontic treatment is of great concern and poses risks to the teeth and surrounding tissues. Orthodontic tooth movement can be accelerated by introducing regional insult. Evidence suggests piezocision to be minimally invasive and clinically effective.

OBJECTIVE

The aim of the present study was to compare the effectiveness of conventional and piezocision-assisted orthodontics in relieving anterior crowding.

SEARCH METHODS

Electronic and manual searches were conducted in databases including PubMed, Dental and Oral Science, CINAHL, and Cochrane Central Register of Controlled Trials until April 2019.

SELECTION CRITERIA

Randomized and non-randomized controlled trials were included.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two authors from the studies that fulfilled inclusion criteria. The primary outcome assessed was time required for the alleviation of crowding. The secondary outcomes evaluated were pain, root resorption, and periodontal health. The risk of bias in the clinical trials was evaluated according to the Cochrane Collaboration's tool. Studies having homogenous data were included in the meta-analysis using the RevMan software.

RESULTS

Initial search yielded 3018 studies with eight articles meeting the inclusion criteria, six were randomized controlled trials and two were non-randomized controlled trials. Significant differences were found in alignment time between conventional and piezocision-assisted orthodontic treatment. However, gingival health, pain experienced by the patient, and root resorption showed non-significant differences. The forest plot of meta-analysis depicted significant mean difference of -46.44; 95 per cent confidence interval (CI) -87.95, -4.93; P ≤ 0.03 in the alignment time. Difference in pain levels was found to be non-significant (P = 0.78).

LIMITATIONS

There is a shortage of high-quality randomized controlled trials with a limited sample size and lack of standardization of piezocision protocol.

CONCLUSIONS AND IMPLICATIONS

According to the existing evidence, piezocision is effective in reducing tooth alignment time and alleviating crowding when compared to conventional therapy. Pain levels showed insignificant differences revealed in meta-analysis. Weak evidence suggests that there are no negative effects on periodontal health and root resorption after performing piezocision.

REGISTRATION

PROSPERO (CRD42019134398).

Disentangling the effects of CAD/CAM customized appliances and piezocision in orthodontic treatment: New evidence

OBJECTIVES

To discern the effects of computer-aided design (CAD)/computer-aided manufactured (CAM) customized appliances and piezocision on orthodontic treatment (OT).

MATERIALS AND METHODS

The study combined findings from two previously published randomized controlled trials: (1) standard OT vs piezocision-assisted standard OT, and (2) CAD/CAM OT vs piezocision-assisted CAD/CAM OT. Piezocision is a minimally invasive corticotomy surgical procedure used to accelerate orthodontic treatment and CAD/CAM refers to CAD/CAM customized brackets and archwires. The outcomes were the overall treatment time, and the durations of the alignment phase and fine-tuning phase. Clinical and radiological features also were evaluated.

RESULTS

The combined study included 48 patients with similar baseline characteristics. Compared to the standard treatment, CAD/CAM technology alone significantly decreased the overall median OT time from 543 to 394 days (P < .001) and from 543 to 254 days (P < .0001) when combined with piezocision. Although piezocision significantly reduced the duration of the alignment phase in the mandible and maxilla, CAD/CAM technology considerably shortened the fine-tuning phase. All periodontal and radiographic parameters remained stable from the start to the end of treatment in all groups.

CONCLUSIONS

CAD/CAM technology combined with piezocision accelerates the entire OT process, during the alignment phase for piezocision and during the fine-tuning phase for CAD/CAM, with a global reduction of the overall treatment time of more than 50%.

Effect of micro-osteoperforations on external apical root resorption: A randomized controlled trial

Objective

This study aimed to investigate the effect of micro-osteoperforations (MOPs) on external apical root resorption (EARR) during the initial orthodontic alignment phase of maxillary anterior crowding.

Methods

Thirty patients (25 females, 5 males; mean age, 22.66 ± 3.27 years) who presented with moderate crowding of the upper labial segment and underwent extraction-based fixed appliance treatment were recruited. They were randomly allocated to receive adjunctive therapy with MOPs (n = 15) or treatment with fixed appliances only (control group; n = 15). EARR was measured from long-cone periapical radiographs taken at the start and the sixth month of treatment. A correction factor for the enlargement difference was used to calculate EARR. Data were analyzed with descriptive statistics and repeated-measures analysis of variance.

Results

The mean root lengths of 168 teeth were measured and showed no statistically significant difference (p > 0.05) after six months of fixed appliance treatment in the MOP (mean difference [MD] = 0.13 mm; 95% confidence interval [CI] = −0.10–0.35) and control group (MD = 0.14 mm; 95% CI = −0.10–0.37). Most of the roots in the MOP and control groups (42.86% and 52.38%, respectively) showed only mild resorption. Less than 8% of the roots in both groups (7.14% in the MOP group and 4.76% in the control group) showed moderate resorption.

Conclusions

Acceleration of orthodontic tooth movement with adjunctive MOPs therapy during the alignment phase does not exacerbate EARR in patients with moderate crowding of the upper labial segment in comparison with controls.

Comparison of rate of orthodontic tooth movement in adolescent patients undergoing treatment by first bicuspid extraction and en-mass retraction, associated with low level laser therapy in passive self-ligating and conventional brackets: A randomized controlled trial

BACKGROUND

Low Level Laser Therapy (LLLT) is one of the various interventions to accelerate the rate of Orthodontic Tooth Movement (OTM) in adolescent patients who are undergoing en-mass retraction after all first bicuspid extractions.

OBJECTIVES

To assess the efficacy of LLLT in increasing the rate of OTM.

MATERIALS AND METHODS

Setting and sample population: Institutional Department of Orthodontics and Dentofacial Orthopaedics. Participants, study design and methods: 65 Patients requiring all first premolar extractions were randomly allocated to three groups. Two groups (Comprising of passive self-ligating brackets and conventional brackets) were treated with LLLT and one group served as the control (conventional brackets). The allocation ratio was 1:1:1.32. Eligibility criteria: adolescent patients with sound and healthy permanent dentition with Little's Irregularity Index<5mm.

MAIN OUTCOME

rate of tooth movement in mm/month. Randomization and blinding: computer-generated random allocation sequence; only the data analyser was blinded by coding the digital models. Patients were reviewed once every month till the completion of space closure.

STATISTICS

data normality was checked using Shapiro-Wilks test and Q-Q Plot. Parametric tests were applied for the inferential statistics (ANCOVA) with Dunnett's t test being used for post hoc analysis.

RESULTS

There was a statistically significant enhancement in the rate of OTM in the 2 experimental groups (0.68/0.67mm/month in the right and left side of the maxilla and 0.66/0.65mm/month in the right and left side of the mandible) when compared with the control group (0.48mm/month in the maxilla and 0.48mm/month in the mandible) (P<0.05), but when the 2 experimental groups were compared no difference was observed (P>0.05). No serious harms were reported.

CONCLUSION

A significant increase in the rate of OTM was observed with the application of LLLT. No difference was observed in the rate of OTM when comparing different ligation methods treated with LLLT.

REGISTRATION

National Trial Registry (CTRI No- CTRI/2018/04/013156). Protocol was not published before trial commencement.