Dentoskeletal effects of mini-screw assisted, non-surgical palatal expansion in adults using a modified force-controlled polycyclic protocol: a single-centre retrospective study.

OBJECTIVES: This study assessed the dental and skeletal effects of pure bone-borne, non-surgical maxillary expansion, using a modified force-controlled polycyclic protocol. METHODS: Records of 17 adult patients, mean age 24.1 years; range 18-39 years, who had undergone maxillary expansion using a bone-borne Quad-expander (with 4 mini-screws), were analysed. In all patients, 0.17 mm/day of expansion was completed for 1 week, followed by a cyclic protocol of expansion of forward and backward turns until the force needed to turn the expander was below 400 cN, assessed weekly. After this, expansion continued at a rate of 0.17 mm/day until the desired amount of expansion was achieved. Cone beam computer tomography scans were taken pre- and post-expansion. RESULTS: The mid-palatal suture was successfully opened in 100% of patients included in this study. Axially, the amount of skeletal opening at the posterior nasal spine was 61% of the anterior nasal spine. Expansion was pyramidal in the coronal plane. Significant increases at the dental and skeletal levels were achieved, with changes at the skeletal level reaching 73%. The alveolar bone angle increased more than the angular changes at the molars and premolars. LIMITATIONS: This is a retrospective study with short-term results. CONCLUSION: The Quad-expander, with a force-controlled polycyclic expansion protocol, effectively produced a significant increase in maxillary width in skeletally mature subjects in the short term.

Physical properties of root cementum: Part 29. The effects of LED-mediated photobiomodulation on orthodontically induced root resorption and pain: a pilot split-mouth randomized controlled trial.

OBJECTIVES: To examine the effects of light-emitting diode (LED)-mediated photobiomodulation (PBM) on orthodontic root resorption and pain. METHODS: Twenty patients (3 males, 17 females, mean age 15 years 6 months) needing bilateral maxillary first premolar extractions for orthodontic treatment were included in this single-centre, split-mouth randomized controlled trial. Both premolars received 150 g of buccal tipping force for 28 days. One side was randomly assigned to receive intraoral 850 nm wavelength, 60 mW/cm2 power, continuous LED illumination via OrthoPulse device (Biolux Research Ltd, Vancouver, British Columbia, Canada) for 5 minutes/day. The other side served as control. After 28 days, both premolars were extracted and scanned with micro-computed tomography for primary outcome assessment of root resorption crater volume measurements. For secondary outcome assessment, visual analogue scale pain questionnaires were used for both sides at 24 hours, 48 hours, 72 hours, and 7 days. Randomization was generated using www.randomization.com and allocation was concealed in sequentially numbered, opaque, sealed envelopes. Blinding was not possible during the experiment due to the use of tape to block light on control side of the devices. Assessors were blinded during outcome assessments. RESULTS: All 40 premolars from 20 patients were included. There was no significant difference in the mean total root resorption between the LED PBM and control sides (mean 0.216 versus 0.284 mm3, respectively, P = 0.306). The LED side was associated with less pain at 24 hours (P = 0.023) and marginally more pain at subsequent time points, which was not statistically significant. No harms were observed. LIMITATIONS: Short study duration and the inability to blind patients and clinician during clinical part of study. CONCLUSION: This 28-day randomized split-mouth controlled trial showed that daily, LED-mediated PBM application, when applied for 5 minute/day, does not influence orthodontic root resorption. It is associated with significantly less pain 24 hours after the application of orthodontic force, but no difference thereafter. These results should be tested on patients undergoing a full course of orthodontic treatment. TRIAL REGISTRATION: Clinical Trials Registry ACTRN12616000652471.

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.

A retrospective long-term comparison of early RME-facemask versus late Hybrid-Hyrax, alt-RAMEC and miniscrew-supported intraoral elastics in growing Class III patients.

OBJECTIVE: To compare the long-term dentoskeletal effects of early treatment with banded or bonded RME (Rapid Maxillary Expansion)-Face Mask (RME-FM) versus late treatment with bonded Hybrid-Hyrax, alt-RAMEC (Alternate Rapid Maxillary Expansion and Contraction) and intraoral Class III elastics anchored to miniscrew-reinforced-Lower-lingual-Arch (alt-RAMEC-HH-LLA) in growing, maxillary retrognathic patients. MATERIALS AND METHODS: Two groups were matched at long-term follow-up retrospectively. Patients received either early RME-FM (n=16, 5 males, 11 females, age T1: 6.5±0.9 years, age T2: 15.8±2.5 years) or late alt-RAMEC-HH-LLA (n=15, 7 males, 8 females, age T1: 12.52±0.94 years, age T2: 16.8±0.9 years). Total follow-up was 9.2±2.3 years and 4.2±0.2 years respectively, including fixed appliances to compete treatment. RESULTS: Both treatments resulted in Class III correction except one unsuccessful case of alt-RAMEC-HH-LLA. Active maxillary protraction was 1.6±0.5years with RME-FM and 0.5 years with alt-RAMEC-HH-LLA being significantly shorter (P<0.001). Values at T2 estimation with multivariate linear regression for correlated multiple outcomes, conditional on baseline estimates, age and sex showed alt-RAMEC-HH-LLA inducing significantly more retroclined lower incisors (mean: -6.11°; 95%CI: -10.66, -1.57; P=0.01), less overbite (mean: -1.28mm; 95%CI: -1.79, -0.761; P<0.001), less maxillo (Co-A)- (mean: -4.54mm; 95%CI: -7.91, -1.16; P=0.01) mandibular (Co-Gn) (mean: -10.5mm; 95%CI: -17.45, -3.55; P=0.003) projections/size, more open gonial angle (mean: 4.93°; 95%CI: 2.27, 7.59; P<0.001), and less S-N length (mean: -5.04mm; 95%CI: -6.57, -3.51; P<0.001). CONCLUSIONS: Patients treated with either early RME-FM or late Alt-RAMEC-HH-LLA had comparable overall post-pubertal skeletal and overjet corrections. However, the late Alt-RAMEC-HH-LLA showed less correction of dentoalveolar compensations and in particular of the mandibular incisors. The overbite, maxillary and mandibular projection and size were lower and the gonial angle was more open.

The effect of piezocision vs no piezocision on maxillary extraction space closure: A split-mouth, randomized controlled clinical trial.

INTRODUCTION: The aim of this 2-arm-parallel, split-mouth trial was to investigate the effects of piezocision compared with no piezocision on maxillary canine distalization and to evaluate patient perceptions on the surgical procedure. METHODS: Twenty-two participants requiring extractions of maxillary first premolars were recruited from the Department of Orthodontics (Sydney Dental Hospital) waiting list. After leveling and alignment, a minimum of 3 mm space was required for canine retraction. Piezocision cuts distal to the canines were 4 mm long and 3 mm deep into the buccal cortical plate. The canine retraction was initiated on both sides immediately after surgery, with coil springs delivering 150 g of force per side. Random assignment of piezocision or control intervention on the patient's right side was performed (www.randomisation.com) for the random number generation, and allocation concealment was accomplished with opaque, sealed envelopes. Patients were assessed every 6 weeks for coil activation and alginate impressions over 18 weeks. The primary outcome was the amount of tooth movement in mm. Secondary outcomes were canine rotation, anchorage loss measured on scanned dental models, and patient pain levels and perception on piezocision using visual analog scale questionnaires. Blinding was feasible for the dental model measurements. RESULTS: Twenty patients completed the trial. The treatment × time interaction showed no statistically or clinically significant differences in maxillary extraction space closure (b = -0.02; 95% confidence interval [CI], -0.29 to 0.25; P = 0.89) canine rotation (b = -1.45; 95% CI, -4 to 1.09; P = 0.26) and anchorage loss (b = -0.02; 95% CI, -0.38 to 0.34; P = 0.92). All patients except for one had minimal pain associated with the piezocision surgery but found the procedure tolerable and would recommend it. No harm occurred during the trial. CONCLUSIONS: Piezocision-assisted maxillary canine distalization was similar to distalization with conventional orthodontics with patients tolerating the procedure.

The effect of 12 weeks of mechanical vibration on root resorption: a micro-CT study.

OBJECTIVE: The aim was to investigate the effect of mechanical vibration on root resorption with or without orthodontic force application. MATERIAL AND METHODS: Twenty patients who required maxillary premolar extractions as part of orthodontic treatment were randomly divided into two groups of 10: no-force group and force group. Using a split-mouth procedure, each patient's maxillary first premolar teeth were randomly assigned as either vibration or control side for both groups. A buccally directed vibration of 50 Hz, with an Oral-B HummingBird device, was applied to the maxillary first premolar for 10 min/day for 12 weeks. After the force application period, the maxillary first premolars were extracted and scanned with micro-computed tomography. Fiji (ImageJ), performing slice-by-slice quantitative volumetric measurements, was used for resorption crater calculation. Total crater volumes were compared with the Wilcoxon and Mann-Whitney U tests. RESULTS: The total crater volumes in the force and no-force groups were 0.476 mm3 and 0.017 mm3 on the vibration side and 0.462 mm3 and 0.031 mm3 on the control side, respectively. There was no statistical difference between the vibration and control sides (P > 0.05). There was more resorption by volume in the force group when compared to the no-force group (P < 0.05). CONCLUSION: Mechanical vibration did not have a beneficial effect on reducing root resorption; however, force application caused significant root resorption.

The effect of low-level laser therapy on orthodontically induced root resorption: a pilot double blind randomized controlled trial.

Background: The effect of low-level laser therapy (LLLT) on accelerating orthodontic tooth movement has been extensively studied; however, there is limited knowledge on the use of LLLT on orthodontic root resorption. Objective: To investigate the effect of LLLT on orthodontically induced inflammatory root resorption (OIIRR) and to compare the difference between pulsed and continuous LLLT on OIIRR. Trial design: Double-blind, single-centre 3-arm parallel split-mouth randomized controlled trial. Participants: Twenty adolescent patients who required bilateral maxillary first premolar (MFP) orthodontic extractions were recruited from the Sydney Dental Hospital between October 2014 and December 2014. Intervention: All MFPs were tipped buccally for 28 days to induce OIIRR. The experimental premolars (n = 20) received LLLT and the control premolars (n = 20) received placebo-laser on days 0, 1, 2, 3, 7, 14, and 21. Ten experimental premolars received LLLT via continuous delivery and 10 received pulsed delivery. Laser parameter: AlGaAs diode laser of 808 nm wavelength, 0.18 W power, 1.6 J per point, and duration of 9s for continuous mode and 4.5 s for pulsed mode. Outcome: The difference in root resorption crater volume between LLLT and placebo-laser and continuous or pulsed laser delivery after 28 days. Randomization: Randomization was computer-generated, with allocation concealment by opaque sequentially numbered sealed envelopes. Blinding: The participants and operator were blinded. Results: Eighty-eight patients were screened and 20 patients were randomized. Forty premolars were analysed. LLLT resulted in 23 per cent less root resorption compared to the placebo (P = 0.026). Pulsed laser delivery resulted in 5 per cent less root resorption than continuous; however, this was not statistically significant (P = 0.823). No harm was observed. Conclusion: Teeth treated with LLLT had less total root resorption than placebo-laser. Furthermore, there was minimal difference between pulsed or continuous delivery of LLLT. Trial Registration: Clinical Trials Registry (ACTRN12616000829415). Protocol: The protocol was not published before trial commencement.