Canine Rotation Research Articles

Comparative evaluation of interrupted and intermittent forces on canine retraction: an in vivo study.

Various force systems are used in orthodontics to move teeth, such as continuous, intermittent and interrupted. Teeth responds differently to these orthodontic forces. The aim of the study is to compare the rate of canine retraction with intermittent and interrupted forces. A split mouth study was carried among eighteen participants. One side of maxillary arch randomly received interrupted force with elastomeric powerchain while other received intermittent force with elastics with magnitude of 150-170g for canine retraction on each side. For 15 weeks, participants were asked to wear the elastics 8 hours a day whereas the elastomeric powerchains were replaced by operator every 5 weeks. The outcomes were assessed using scanned images of study models collected at the beginning (T0) and 15 weeks later (T3) as well on OPG. Linear and angular measurements were used to measure the distal movement, rotation as well tipping of canines and the results were statistically analysed using Independent t-test. The distal movement of canine on the interrupted force side was 0.98mm/5weeks and on the intermittent force side was 1.06mm/5weeks. The distopalatal rotation on interrupted and intermittent force side was 8.38° and 5.72°. Tipping measured on OPG was 5.72° and 5.27° for interrupted and intermittent force. No statistically significant differences were found. The rate of canine retraction with interrupted force and intermittent force showed no statistically significant differences. Less canine rotation and tipping with intermittent force compared to interrupted force though not statistically significant.

Management of a complete 180° rotation of bilateral maxillary canines

Background: Dental anomalies usually lead to complicated decisions having to be made in terms of the orthodontic treatment of permanent dentition; tooth rotation is the most common of these irregularities. The prevalence rate of this phenomenon is 2.1–5.1% in patients who have not received orthodontic treatment. Purpose: This case report aimed to manage the complete bilateral rotation of maxillary canines with couple force by using a Nance appliance modification. Case: A 17-year-old male patient came in wanting to straighten his teeth. He complained about his bilateral canines, which were not in a normal position. There was an impacted left maxillary second premolar and an ectopically erupted right maxillary first premolar. He also had protrusions in the upper and lower anterior teeth and crowding in the lower anterior teeth as well as upper and lower midline deviations. Case Management: A clinical examination showed a class I relationship between the dental and cephalometry measurements and highlighted a class I skeletal pattern. The upper right first premolar was extracted and the left second premolar had undergone an odontectomy to allay protrusion and correct crowding. Bilaterally rotated upper canines were derotated using a modified Nance appliance and an elastomeric chain with couple force. Conclusion: The success of the orthodontic treatment was influenced by the specific nature of the patient’s dental and medical history, extraoral and intraoral examination, diagnosis and treatment planning, which was followed by a systematic approach to treatment. The Nance appliance modification reduced the total treatment time by achieving controlled anchorage and derotation of the canines.

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

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. 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 3mm space was required for canine retraction. Piezocision cuts distal to the canines were 4mm long and 3mm deep into the buccal cortical plate. The canine retraction was initiated on both sides immediately after surgery, with coil springs delivering 150g 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 6weeks for coil activation and alginate impressions over 18weeks. 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. 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. Piezocision-assisted maxillary canine distalization was similar to distalization with conventional orthodontics with patients tolerating the procedure.

The effect of intra-oral LED device and low-level laser therapy on orthodontic tooth movement in young adults: A randomized controlled trial

This randomized controlled clinical trial aimed to assess the effect of LED5 and LLLT6 in a three-arm parallel setting. Sixty patients who needed the maxillary first premolar extraction were allocated to three groups using the stratified block randomization method. In the LED group, a custom-made device with a wavelength of 640nm and a power density of 40 mW/cm2 was used 5min/day. In the laser group, Ga Al As7 laser with a wavelength of 810nm and a power of 100 mW was used on days 0, 3, 30, and 60 each time for 18seconds. Patients in the control group received placebo treatment as the laser group protocol, using a coated light cure device. Models were made at baseline and monthly until the end of the retraction. The rate of canine retraction was the primary outcome, while canine rotation and pain were secondary outcomes. The final data were anonymous for the outcome assessor and statistical consultant. Data were analyzed per protocol using a linear mixed model. The rate of canine retraction significantly increased by 60.8% in the laser group, while it increased not significantly by 26% in the LED group compared with the control group. There was no significant difference among the groups in terms of tooth rotation and pain. LLLT can accelerate orthodontic tooth movement (OTM). LED with the present setting couldn't increase the rate of OTM. LLLT and LED did not affect canine rotation or pain. IRCT20120220009086N4. On 1 June 2019 was retrospectively registered.

Canine angulation and rotation during canine retraction using elastomeric chains with and without a power arm

Background: During canine retraction, orthodontic forces are applied away from the tooth’s center of resistance. This introduces canine distal tipping and mesiobuccal rotation. The correction of these unwanted movements will prolong treatment time. Applying the force closer to the center of resistance should decrease this unwanted tooth movement. Objective: Compare the canine angulation and rotation during canine retraction with and without the use of power arm. Materials and Methods: Twenty-four female orthodontic patients (age 19.32± 4.17 years) with dental Class II indicated for bilateral maxillary first premolar extraction and maximum anchorage were included in this study. The canines were retracted with elastomeric chains over 0.016” X 0.022” statinless steel arch wires to reduce friction. The retraction force was 150g. In twelve patients, the canines were retracted using a power arm fixed to the vertical slots of the canine brackets. For the other twelve patients, the elastic chains were attached to the bracket hooks. Results: Before treatment, the canine angulation and rotation was similar for the two groups. The canine angulation was 12.38± 8.27 and 14.5o± 9.41 for the group with the power arm and without, respectively. while canine rotation was 64.74o± 11.65 and 63.12o± 14.88, respectively. Post-retraction, there was no significant difference in the canine angulation or rotation between the groups. Conclusion: Compared to canine retraction with a power arm, conventional canine retraction with elastomeric chains attached to the bracket hook may provide similar control over distal tipping, provided a stiff 0.017” X 0.025” stainless steel arch wire is used.

Biomechanics of mini-implants: analysis of the adverse effects of four clinical situations and proposed resolutions

The biomechanical adverse effects generated by our treatments must be considered among the failures of mini-implants, certainly excellent means of anchorage. The aim of this article was to illustrate and comment on mechanical adverse effects and to propose solutions. Four common clinical situations in vestibular technique are analyzed, decomposed three-dimensionally and solved. Maxillary incisor intrusion in direct traction (mini-implant between lateral incisors and canines in direct anchorage) can lead to a disto-labial rotation of the supporting teeth and an incisor flaring. Maxillary incisivo-canine retraction (mini-implant between 5 and 6 in direct anchorage) leads to a canine rotation, a clockwise rotation of the occlusal plane and a version of the adjacent teeth. The maxillary molar two-steps distalization (mini-implant between 5 and 6 with metal ligation to the canine) causes a rotation of the adjacent to the spring teeth, an incisor flaring and a molar disto-version. The protraction of a mandibular molar (mini-implant between 3 and 4 in direct anchorage) causes a disto-labial rotation, a lingual torque and a mesio-version of the molar as well as an incisor flaring and a clockwise rotation of the occlusal plan. The compensation bends on the adjacent teeth, the choice of the location and the type of mini-implant, the use of a power arms to get closer to the center of resistance are among the means of resolution. If mini-implants anchorage allows a significant quantitative effect, adverse effects should be considered individually with a three-dimensional biomechanical analysis.

Assessment of the effects of local platelet-rich fibrin injection and piezocision on orthodontic tooth movement during canine distalization

The study aimed to evaluate and compare the effects of local platelet-rich fibrin (PRF) injection and piezocision applications on tooth movement during canine distalization, as well as to evaluate any changes in the periodontal parameters. Twenty-four patients were randomly divided into 2 groups. A randomly selected side of the maxillary arch received either PRF injection (PRF group) or piezocision (piezocision group). The contralateral sides of both groups served as the controls. After piezocision and PRF injection applications, canine distalization was initiated in both groups with a 150g force. Patients were followed every 2weeks for a total 12 of weeks. The following variables were evaluated: cephalometric measurements, the amount of canine distalization, molar mesialization, canine rotation, transversal changes in dental models, and periodontal parameters. The amount of canine distal movement was found to be greater in the experimental sides than in the control sides in both groups at 12weeks (P<0.05). There were no differences in the amount of molar mesialization, canine rotation, or transversal measurements in both groups when compared with the experimental sides with the control sides (P>0.05). There were no differences in the skeletal measurements or periodontal parameters in both groups (P>0.05). In both groups, the maxillary incisors were retroclined and retracted. PRF and piezocision accelerated tooth movement, but there were no differences between the 2 applications in terms of speed, amount, duration of tooth movement, or periodontal parameters during canine distalization.

Effects of different alveolar bone finite element models on the biomechanical responses of periodontal ligament

In the study of oral orthodontics, the dental tissue models play an important role in finite element analysis results. Currently, the commonly used alveolar bone models mainly have two kinds: the uniform and the non-uniform models. The material of the uniform model was defined with the whole alveolar bone, and each mesh element has a uniform mechanical property. While the material of the elements in non-uniform model was differently determined by the Hounsfield unit (HU) value of computed tomography (CT) images where the element was located. To investigate the effects of different alveolar bone models on the biomechanical responses of periodontal ligament (PDL), a clinical patient was chosen as the research object, his mandibular canine, PDL and two kinds of alveolar bone models were constructed, and intrusive force of 1 N and moment of 2 Nmm were exerted on the canine along its root direction, respectively, which were used to analyze the hydrostatic stress and the maximal logarithmic principal strain of PDL under different loads. Research results indicated that the mechanical responses of PDL had been affected by alveolar bone models, no matter the canine translation or rotation. Compared to the uniform model, if the alveolar bone was defined as the non-uniform model, the maximal stress and strain of PDL were decreased by 13.13% and 35.57%, respectively, when the canine translation along its root direction; while the maximal stress and strain of PDL were decreased by 19.55% and 35.64%, respectively, when the canine rotation along its root direction. The uniform alveolar bone model will induce orthodontists to choose a smaller orthodontic force. The non-uniform alveolar bone model can better reflect the differences of bone characteristics in the real alveolar bone, and more conducive to obtain accurate analysis results.

Effect of light-emitting diode–mediated photobiomodulation on extraction space closure in adolescents and young adults: A split-mouth, randomized controlled trial

This split-mouth trial aimed to examine the effects of light-emitting diode (LED)-mediated photobiomodulation compared with no photobiomodulation on maxillary canine distalization. Twenty participants (10 males and 10 females; aged 11-20years) requiringbilateral extraction of maxillary first premolars were included from the Sydney Dental Hospital waiting list. After premolar extractions, leveling, and alignment, canines were retracted on 0.020-in stainless steel wires with coil springs delivering 150g of force to each side. Each patient's right side was randomly assigned to experimental or control using www.randomisation.com, and allocation concealment was performed with sequentially numbered, opaque, sealed envelopes. The experimental side received 850nm wavelength, 60mW/cm2 power, continuous LED with OrthoPulse device (Biolux Research Ltd, Vancouver, British Columbia, Canada) for 5min/d. For the control side, the device was blocked with opaque black film. Patients were reviewed at 4-week intervals for force reactivation and intraoral scanning over 12weeks. The primary outcome was the amount of tooth movement, and secondary outcomes were anchorage loss and canine rotation, all measured digitally. Blinding for study participants and the treating clinician was not possible; however, blinding was done for the measurements by deidentifying the digital scans. Linear mixed models were implemented for the data analysis. Nineteen participants concluded the study. Data analysis showed that the treatment×time interaction was not significant, suggesting no difference in space closure (unstandardized regression coefficient [b], 0.12; 95% confidence interval [CI], -0.05 to 0.29; P=0.17), canine rotation (b, 0.21; 95% CI, -0.82 to 1.25; P=0.69), and anchorage loss (b, -0.01, 95% CI, -0.28 to 0.26, P=0.94). No harms were noted. Daily 5-minute application of LED did not result in clinically meaningful differences during extraction space closure compared with no LED application. Australian New Zealand Clinical Trials Registry (ACTRN12616000652471). The protocol was not published before trial commencement. This research was funded by the Australian Society of Orthodontists Foundation for Research and Education.

Comprehensive comparison of canine retraction using NiTi closed coil springs vs elastomeric chains.

To compare canine retraction using NiTi closed coil springs vs elastomeric chains comprehensively in a split-mouth randomized controlled trial. The canines in 64 quadrants were randomly retracted into the first premolar extraction spaces using NiTi closed coil springs or elastomeric chains, in the maxilla and mandible. The retraction force was 150 g. Cone beam computed tomography scans and study models were obtained before the start of canine retraction and 6 months later. The rate and total amount of canine retraction, canine rotation, tipping, and root resorption were evaluated. A visual analogue scale was used to evaluate patients' pain experience. The two methods were statistically similar for dental changes, rate of canine retraction, and root resorption. However, patients reported significantly more days of pain with the elastomeric chain compared to the NiTi closed coil springs. Within the constraints of the current study, using either NiTi closed coil springs or elastomeric chains as force delivery systems for canine retraction results in no significant difference in the rate of canine retraction, tipping, rotation, or root resorption. Pain experience during retraction using elastomeric chains is more significant yet needs further investigation.

Effects of a ceramic active self-ligating bracket on retraction/tipping/rotation of canine, premolar mesialization, and transverse arch dimensions: A preliminary single-blind split-mouth randomized clinical trial

There is no clinical study on ceramic self-ligating brackets (SLBs). Therefore, this preliminary study was conducted for the first time to address its effects. This split-mouth randomized trial was performed on 32 quadrants in 16 orthodontic patients needing extraction of maxillary premolars and distalization of canines. In each blinded patient, right/left sides were randomized into control (ceramic bracket) and experimental (ceramic SLB) groups. Dental stone models were taken before canine retraction and 3 months into retraction. Models were digitized as three-dimensional models. Changes were measured on superimposed models. Groups were compared using Wilcoxon signed-rank test (α = 0.05, β = 0.1). Both bracket types caused significant changes after 3 months in terms of all assessed clinical outcomes (P ≤ 0.002). Compared to conventional ceramic brackets (control), ceramic SLBs reduced retraction rate (P = 0.001), canine rotation (P = 0.001), canine tipping (P = 0.002), and arch expansion at the canine site (P = 0.003). However, the extents of anchorage loss (P = 0.796) and arch constriction in the premolar area (P = 0.605) were not statistically different between the bracket types. Compared to conventional metal-lined ceramic brackets, active ceramic SLB can increase the duration of canine distalization, while reducing canine rotation and tipping (inducing more bodily movements). The loss of anchorage with ceramic SLB was similar to that of conventional ceramic bracket after 3 months of treatment (considering the lower rate of SLB canine retraction during that time). Both brackets similarly constricted the arch at the premolar site. In the canine area, they expanded the arch, with the SLB causing smaller extents of expansion.

Efficacy of Er,Cr Laser incision Corticotomy in Rapid Maxillary Canine Retraction: A Split-Mouth Randomized Clinical Trial.

Introduction: This study sought to evaluate the efficacy of lasercision corticotomy for the acceleration of canine movement. Our secondary objectives were assessing the canine rotation, the rate of anchorage control, the level of pain, and the gingival index (GI). Methods: Twelve orthodontic patients (9 females and 3 males) referring to the School of Dentistry and one dental clinic from May 2019 to September 2019 participated in this split-mouth randomized clinical trial. The allocation of the test and control sides was performed by flipping a coin. The mean age of patients was 18.91±3.87 years (range 15-30 years). The treatment plan included maxillary first premolar extraction. Following the initial leveling and alignment phase, an initial impression was made. Corticotomy was carried out with the erbium, chromium-doped yttrium scandium gallium garnet (Er, Cr: YSGG) laser (3.5 W, 30 Hz, 40% air, 80% water) in one maxillary quadrant (the laser side). Canine retraction was immediately initiated following surgery using nickel-titanium closed-coil springs with 150 g force. The impression was repeated 1 month after the onset of retraction. The casts were scanned, and the distance between the canine cusp tip and the rugae line was measured to quantify the amount of anteroposterior canine movement. The molar anchorage control was also evaluated by measuring the distance between the mesial contact of the permanent first molar and the rugae line. Gingival health was evaluated using the GI. The modified McGill pain questionnaire was used to assess the level of patients' pain. Results: Lasercision corticotomy accelerated canine retraction with no adverse effect on gingival health. Anchorage loss in the posterior teeth and pain scores were not significantly different between the control and laser sides. Conclusion: Laser corticotomy can effectively accelerate canine retraction with no complications or discomfort for the patients.

Fiber- Reinforced Composite for Orthodontic Anchorage Technique

Introduction: In orthodontic treatment, adequate anchorage is necessary to move the intended teeth. In some cases, just anterior teeth are malaligned, while posterior occlusion is acceptable. Therefore, the posterior teeth could be integrated by fiber-reinforced composite (FRC) to provide a rigid anchorage. This method proved advantageous since brackets are bonded just to anterior segment, while posterior segments remain intact. Case description: The current article presents the orthodontic treatment of an adolescent girl with malalignment and rotation of upper incisors and canines. Posterior occlusion was admissible. Posterior anchorage was provided by FRC bars, while anterior teeth alignment was performed by routine fixed orthodontic appliances. Orthodontic treatment was completed within six months. It is worthy to note that the posterior occlusion was maintained as before treatment.

The effects of a clinically feasible application of low-level laser therapy on the rate of orthodontic tooth movement: A triple-blind, split-mouth, randomized controlled trial

This split-mouth trial aimed to investigate the effect of low-level laser therapy (LLLT) on the amount of maxillary canine distalization when applied every 4weeks over 12weeks. Twenty-two adolescents and young adults (15 female, 7 male; aged 13-25years; n=22) requiring bilateral maxillary first premolar extractions were recruited. After extractions and leveling-alignment, canines were retracted using closed-coil nickel-titanium springs delivering 150g of force. LLLT was applied to 8 intraoral points on the buccal and palatal sides around the canine root for 10seconds per point, on day 0, 28, and 56 with the control side receiving sham application. Alginate impressions were taken every 4weeks on day 0, 28, 56, and 84. The amount of tooth movement, anchorage loss, and canine rotation were measured digitally. Randomization was generated using www.randomisation.com and allocation concealment through sequentially numbered, opaque, sealed envelopes. Participants, operator, and statistic assessor were blinded. Linear regression modeling accounting for clustering within each patient was used to identify differences between LLLT and control sides. Twenty-one patients completed the study. The total amount of tooth movement was similar in the LLLT (2.55±0.73mm) and control group (2.30±0.86mm), whereas 0.25mm (95% confidence interval, -0.21, 0.71mm) of difference was insignificant (P=0.27). No significant differences were found for anchorage loss (P=0.22) or canine rotation (P=0.25). No harms were reported. Application of LLLT every 4weeks did not result in differences in the amount of tooth movement, anchorage loss, and canine rotation during extraction space closure.

Vertical Movements and Rotations of the Ectopic Mandibular Canine Registered in Cross-Sectional and Longitudinal Studies on Orthopantomograms from 54 Patients Diagnosed with Mandibular Canine Ectopia

IntroductionThe hypothesis behind this study is that the ectopic mandibular canines move vertically in the mandibular bone during childhood and puberty. The aim was to evaluate interosseous vertical movements of the ectopic mandibular canines for improvement of diagnostic treatment and planning.Material and MethodsThe study had two parts: a cross-sectional study and a longitudinal study. The cross-sectional study included orthopantomograms from 54 patients (ages 9 years and 6 months to 16 years) with ectopic mandibular canines. The longitudinal study included series of orthopantomograms from 14 out of the 54 patients. Two methods were involved in both studies. 1) The canine angle expressing the vertical position (angle between canine axis and the vertical line perpendicular to the occlusal plane) was registered. 2) The crown morphology indicating rotation of the canine, as well as the maturity of the canine (Nolla Score System), were registered.ResultsThe cross-sectional study demonstrated that the largest canine angles were observed in the most mature canines, often with the canine crown appearing in the lateral view. The longitudinal study demonstrated in 4 out of the 14 cases that the canines moved in the vertical plane towards a more upright position, resulting in a smaller angle, while the other ten cases moved during the observation period to a lower and more horizontal position, creating a larger angle. The crown morphology was unchanged in the uprighting cases, while rotation occurred in the ten cases undergoing increasing inclination. Maturity increased during all observation periods.ConclusionsThis study is thefirst study which demonstrates and accordingly proves the hypothesis that the vertical movements and rotation of mandibular canines can occur in children and young adults diagnosed with ectopic mandibular canine eruption. These spatio-temporal movements are believed to be of importance for diagnostics and treatment planning of ectopic mandibular canines

Complications encountered during Forsus Fatigue Resistant Device therapy.

ABSTRACTIntroduction: Fixed functional appliances are non-compliant solutions to Class II malocclusion treatment. The clinician, however, should be careful of unexpected complications during the therapy. Methods: 58 female adolescents who presented with Class II malocclusion due to deficient mandible were treated with Forsus Fatigue Resistant Device (FFRD) therapy until an overcorrection to an edge to edge incisor relationship was achieved. Results: Incisor relationship and overjet were corrected successfully in all the subjects. Twenty-two patients had a complications-free treatment, while several complications were encountered with the remaining 36 subjects. In particular, mandibular canine rotation and development of posterior crossbites were the most common complications, with percentages of 51.7% and 25.9% respectively. Other complications included the breakage and shearing of the extraoral tubes of the first molar bands, and excessive intrusion of the upper first molars. Conclusions: FFRD is an efficient appliance for treatment of Class II malocclusion; however, different complications were encountered during the appliance therapy. A focus on taking precautions and applying preventive measures can help to avoid such problems, reducing the number of emergency appointments and enhancing the treatment experience with the appliance.

Comparing the rotational control during canine retraction using two different bracket systems – Synergy and Self Ligating brackets – Split mouth study

Canine, being the cornerstone of the dental arches, shares an important role in oral functions, esthetics, arch shape and stability. With the new bracket systems that have come to light, which have reduced friction, there is not much literature on how much of a rotation control they have on the cuspids. Hence this study is conducted to compare the efficiency of two least frictional resistance offering brackets – Self-ligating and synergy brackets in terms of rotational control. The study was designed as a prospective randomized controlled split-mouth clinical trial, which included 16 subjects of ages 12-30 years, divided into two groups, left, and the right quadrants receiving Self Ligating and Synergy brackets based on simple randomization, along with a 19*25" SS wire and closed coil springs for individual canine retraction. The patients were reviewed every 21 days for four appointments, and records were taken for each review. Photographs were taken of the cast at every review, and the degree of canine rotation was measured and compared. The results indicate that there is no statistical difference between both the groups in the amount of canine rotation during individual canine retraction with a p-value greater than 0.05 at every interval. The results also indicate that there is a significant amount of canine rotation in Group 1 – Self-ligating brackets and Group 2 – Synergy brackets independently, when comparing T0 to every interval. Overall results show that there is no significant statistical difference between Synergy and Self-Ligating brackets in the amount of canine rotation during canine retraction. The mean or average amount of canine rotation for Group I Self-ligating was 3.32º ±6.55°. The mean or average amount of canine rotation for Group 2 Synergy was 4.08º ±3.85°.

The Effectiveness of Micro-osteoperforations during Canine Retraction: A Three-dimensional Randomized Clinical Trial.

Aim:A major challenge in orthodontics is decreasing treatment time without compromising treatment outcome. The purpose of this split-mouth trial was to evaluate micro-osteoperforations (MOPs) in accelerating orthodontic tooth movement.Materials and Methods:Eight patients of both genders were selected, age ranging between 15 and 40 years, with Class II Division 1 malocclusion. The participants in this trial with MOPs were randomly allocated to either the right or the left side, distal to the maxillary canine. First maxillary premolars were extracted as part of the treatment plan on both sides and then canine retraction was applied. Miniscrews were used to support anchorage. MOP side received (three small perforations) placed on the buccal bone, distal to the maxillary canine, on randomly selected side using an automated mini-implant driver and the other side was the control side. Blinding was used at the data collection and analysis stages. The primary outcome was the rate of canine retraction measured with a three-dimensional (3D) digital model from the baseline to the first 2 weeks superimposed at the rugae area from the baseline to the first, second, and third months. The following secondary outcomes were examined: anchorage loss, canine tipping, canine rotation, root resorption, plaque index, and gingival index. Pain level, pain interference with the patients’ daily life, patients’ satisfaction with the procedure and degree of ease, willingness to repeat the procedure, and recommendation to others were also evaluated.Results:No statistically significant difference was observed in the rates of tooth movement between the MOP and the control sides at all-time points (first month: P = 0.77; mean difference, 0.2 mm; 95% CI, −0.13, 0.18 mm; second month: P = 0.50; mean difference, −0.08 mm; 95% CI, −0.33, 0.16 mm; third month: P = 0.76; mean difference, −0.05 mm; 95% CI, −0.40, 0.29 mm). There were also no differences in anchorage loss, rotation, tipping, root resorption, plaque index, periodontal index, and pain perception between the MOP and control sides at any time point (P > 0.05). MOPs had no effect on the patients’ daily life except for a feeling of swelling on the first day (P = 0.05). Level of satisfaction and degree of easiness of the procedure were high.Conclusion:According to our clinical trial, MOPs cannot help in speeding up a canine retraction.

Three-dimensional assessment of the effect of micro-osteoperforations on the rate of tooth movement during canine retraction in adults with Class II malocclusion: A randomized controlled clinical trial.

The purpose of this split-mouth trial was to investigate the effect of micro-osteoperforations (MOPs) on the rate of tooth movement. Thirty-two patients (24 female, 8 male; mean age, 19.26±2.48years) who required fixed orthodontic treatment and maxillary first premolar extractions participated in this trial with MOPs randomly allocated to either the right or left sides distal to the maxillary canines. Eligibility criteria included Class II Division 1 malocclusion, healthy periodontal condition, no smoking, and no systemic disease. Miniscrews were used to support anchorage and retract the canines with the aid of closed-coil nickel-titanium springs with 150g of force. Randomization was accomplished with block randomization with a permuted block size of 2 with a 1:1 allocation ratio to either right or left with allocations concealed in opaque, sealed envelopes. Blinding was used at the data collection and analysis stages. Three MOPs were performed using miniscrews (5mm depth, 1.5mm width) on the buccal bone distal to the canines on the randomly selected side. The primary outcome was the rate of canine retraction measured from 3-dimensional digital models superimposed at the rugae area from the baseline to the first, second, and third months. The following secondary outcomes were examined: anchorage loss, canine tipping, canine rotation, root resorption, plaque index, and gingival index. Pain level, pain interference with the patients' daily life, patients' satisfaction with the procedure and degree of ease, willingness to repeat the procedure, and recommendation to others were also evaluated. There was no statistically significant difference in the rates of tooth movement between the MOP and the control sides at all time points (first month: P=0.77; mean difference, 0.2mm; 95% CI, -0.13, 0.18mm; second month: P=0.50; mean difference, -0.08mm; 95% CI, -0.33, 0.16mm; third month: P=0.76; mean difference, -0.05mm; 95% CI, -0.40, 0.29mm). There were also no differences in anchorage loss, rotation, tipping, root resorption, plaque index, periodontal index, and pain perception between the MOP and control sides at any time point (P>0.05). MOPs had no effect on the patients' daily life except for a feeling of swelling on the first day (P=0.05). Level of satisfaction and degree of easiness of the procedure were high. A significant percentage of patients were willing to repeat the procedure and recommend it to others. No serious harm was observed. Three MOPs were not effective in accelerating tooth movement at any time point. Other secondary parameters evaluated were not different between the MOP and control sides except for the feeling of swelling on day 1 on the MOP side. Patients were highly satisfied with the MOP procedure, and many considered MOPs an easy procedure and were willing to repeat and recommend it to friends. This trial was registered at Clinicaltrials.gov with identifier number NCT02473471. The protocol was not published before trial commencement. This work was supported by Jordanian University of Science and Technology (grant number 20150263). No conflict of interest is declared.

Correction of a Severely Rotated Mandibular Canine in an Adult Patient Using Invisalign: A Case Report

Introduction: The Invisalign system has been used in the orthodontic treatment of numerous types of malocclusions. However some clinicians have reported difficulty incorrecting rotations particularly in canines and premolars using the Invisalign appliance system. This case report describes the orthodontic treatment of an adult patient with severe canine rotation (more than 45°) and crowding on upper and lower tooth.Methods: The clinical examination included extra-oral and intra-oral photographs, panoramic radiographic, lateral cephalometric, stone casts, and upper and lower arch analysis obtained from ClinCheck 3.0.The treatment planning was resolved the crowding in both upper and lower arches and the severe rotation of 33 tooth (46°) using Invisalign system as well as the canine and molar relationship, dental verticalization, adequate over jet, overbite and dental midline using the same system. The duration of the treatment was approximately eight months.Results: In Post-treatment extra oralphotographs, no significant changes were observed at the end of the treatment. Intraoral photographs showed an important and notable improved aesthetics. The canine relationship improved slightly and molar Class Irelationship was maintained. An increase in transverse diameter was observed at the level of first premolars, second premolars and first molars. The overbite was improved. The crowding and the severe canine rotation were corrected. No obvious root resorption was radiographically evident and slight cephalometric changes.Conclusion: The treatment with the Invisalign system resolved the complaint of our patient so this system could be considered as an option that offered good results in the treatment of upper and lower crowding of arches involving severe canine rotation.