BACKGROUND: Extraction space closure is a challenging phase during orthodontic treatment that affects not only the total treatment duration but also the whole treatment outcome.
OBJECTIVE: To compare the efficiency of friction and frictionless mechanics during en-masse retraction of maxillary anterior teeth in adult patients with bimaxillary dentoalveolar protrusion.
METHODS: Two-arm parallel group, single-center randomized clinical trial.
METHODS: Thirty-two adult patients with bimaxillary protrusion were recruited and randomly allocated to two different retraction mechanics. A friction group, using NiTi coil springs and a frictionless group using closing T-loops for en-masse retraction. Randomization in a 1:1 ratio was generated by Microsoft Excel. The randomization numbers were secured in opaque sealed envelopes for allocation concealment. Retraction started in all patients following first premolars extraction using miniscrews as a source of indirect anchorage. Activation was done on a monthly basis until complete retraction of anterior segment. The rate of retraction, amount of anchorage loss, the dental, and soft tissue changes were analyzed on digital models and lateral cephalograms taken before retraction and after space closure.
METHODS: The outcome assessor was blinded through data concealment during assessment.
RESULTS: Two patients were lost to follow up, so 30 patients completed the trial. The rate of anterior segment retraction was 0.88 ± 0.66 mm/month in the frictionless group compared to 0.72 ± 0.36 mm/month in the friction group which was statistically significant. Anchorage loss of 1.18 ± 0.72 mm in the friction group compared to 1.29 ± 0.55 mm in the frictionless group with no significant difference. Comparable dental and soft tissue changes following en-masse retraction were reported in both groups, with no statistically significant difference.
UNASSIGNED: one patient complained of soft tissue swelling following miniscrew insertion, but the swelling disappeared after one week of using mouth wash.
CONCLUSIONS: The study focused only on the maxillary arch.
CONCLUSIONS: Both mechanics have successfully achieved the required treatment objectives in patients with bimaxillary dentoalveolar protrusion. Frictionless group showed a faster rate of retraction than the friction group, which was statistically but not clinically significant.
BACKGROUND: Clinicaltrials.gov with the identifier NCT03261024.

OBJECTIVE: To assess the success rate of spontaneous space closure after extraction of the first permanent molar (FPM) in the maxilla and the mandible, and to identify the factors that make spontaneous space closure most favorable in each.
METHODS: A retrospective records-based cohort study was conducted through a search of the database of the Public Dental Service, Stockholm County Council, Stockholm, for young adults born between 2000 and 2001, who underwent extraction of one or more FPM between 2006 and 2016. A total of 995 extracted teeth were identified, of which 203 teeth in 155 patients met the inclusion criteria.
RESULTS: Of the 203 extracted teeth, 166 (81.8%) did not receive any orthodontic treatment. The success rate for space closure in orthodontically treated patients was 91.9%. The success rate for spontaneous space closure was 84.3%. All unsuccessful spontaneous space closure in the maxilla occurred in patients older than 12 years. The dental developmental stage of the second permanent molar (SPM) had a statistically significant association with spontaneous space closure in the mandible (P < .001).
CONCLUSIONS: The success rate of spontaneous space closure was high (84.3%) and was higher in the maxilla (94.1%) than the mandible (74.1%). Age at time of extraction and dental developmental stage of the SPM were significant factors for successful spontaneous space closure in the maxilla and mandible, respectively.

BACKGROUND: This single-centered randomized controlled clinical trial aimed to evaluate the effectiveness of micro-osteoperforations (MOPs) in accelerating the orthodontic retraction of maxillary incisors.
METHODS: Forty-two patients aged 16-40 were recruited and randomly assigned into two groups, one which underwent MOPs (MOPG) in the buccal and palatal region of all maxillary incisors immediately before the start of retraction and one which did not (CG). Eligibility criteria included the orthodontic need for maxillary first premolars extraction and space closure in two phases. The primary outcome of the study consisted of measuring the rate of space closure and, consequently, the rate of incisors\' retraction using digital model superimposition 14 days later and monthly thereafter for the next 4 months. The secondary outcomes included measuring anchorage loss, central incisors\' inclination, and root length shortening, analyzed using cone beam computed tomography scans acquired before retraction and 4 months after retraction. Randomization was performed using QuickCalcs software. While clinical blinding was not possible, the image\'s examinator was blinded.
RESULTS: Twenty-one patients were randomly assigned to each group. However, due to various reasons, a total of 37 patients (17 male and 20 female) were analyzed (mean age: 24.3 ± 8.1 years in the MOPG; 22.2 ± 4.2 years in the CG) during the trial. No statistically significant difference was found between the MOPG and the CG regarding the incisors\' retraction measured at different time points at the incisal border (14 days, 0.4 mm vs. 0.5 mm; 1 month, 0.79 mm vs. 0.77 mm; 2 months, 1.47 mm vs. 1.41 mm; 3 months, 2.09 mm vs. 1.88 mm; 4 months, 2.62 mm vs. 2.29 mm) and at the cervical level (14 days, 0.28 mm vs. 0.30 mm; 1 month, 0.41 mm vs. 0.32 mm; 2 months, 0.89 mm vs. 0.61 mm; 3 months, 1.36 mm vs. 1.10 mm; 4 months, 1.73 mm vs. 1.39 mm). Similarly, no statistically significant differences were detected in the space closure, anchorage loss, central incisors\' inclination, and radicular length between groups. No adverse effect was observed during the trial.
CONCLUSIONS: MOPs did not accelerate the retraction of the maxillary incisors, nor were they associated with greater incisor inclination or root resorption. Trial registration ClinicalTrials.gov NCT03089996. Registered 24 March 2017- https://clinicaltrials.gov/ct2/show/NCT03089996 .

OBJECTIVE: A TiNb alloy wire (GUMMETAL® [GM], Toyota Central R&D Labs, Inc., Nagakute, Japan) was recently developed with unique properties for orthodontic applications. This pilot split-mouth randomized controlled trial compared maxillary canine retraction during space closure using sliding mechanics on GM vs. stainless steel (SS) archwires.
METHODS: Subjects who met the inclusion criteria were treated with fixed appliances and maxillary first-premolar extractions between September 2020 and March 2022. After leveling and aligning, maxillary archwires, fabricated by crimping together segments of 0.016×0.022\" GM and SS archwires, were placed and canine retraction initiated using nickel-titanium coil springs. Digital models of the maxillary arch were superimposed at 0, 4, 8 and 12 weeks and the amount of canine movement (mm), rate of movement (mm/month), and 3-dimensional changes (rotational, vertical extrusion, tip) were measured and compared statistically.
RESULTS: Of the 12 subjects recruited, only six completed the study with a median age of 15.8 years (12.0-17.4 years). At 12 weeks, the median canine retraction was 3.41mm (IQR: 2.10, 4.76) with GM versus 3.71mm (IQR: 1.62, 6.45) with SS. The retraction rate was 1.14mm/month (IQR: 0.69, 1.59) with GM, versus 1.24mm/month (IQR: 0.54, 2.15) with SS. The median rotational, vertical and tip changes of the canine were 7.90̊, 0.59mm and 6.15̊ with GM, and 7.25̊, 0.29mm and 2.05̊ with SS. Intergroup differences with all measurements were not statistically significant.
CONCLUSIONS: No significant differences were found between GM and SS during maxillary canine retraction. GM demonstrated clinical potential for space closure mechanics, however, future larger studies are needed.

The alveolar bone loss (ABL) and external apical root resorption (EARR) depict the safety of mesialization of mandibular second molars into the extraction space of mandibular first molars. The aim of this study was to evaluate the ABL and EARR after closure of mandibular first molar extraction space by mesialization of second molar on extraction side (ES) as compared to the contralateral non-extraction side (NES).
A retrospective cross-sectional study was carried out using the pre and posttreatment orthodontic records of young adults with complete set of permanent dentitions treated with extraction of unilateral mandibular first molar and non-extraction treatment on the contralateral side. All patients underwent mini-implant supported mesialization of second molar on ES. The ABL and EARR of second molar on ES and contralateral NES were measured on digital orthopantomograms. The ABL and EARR of second molars on ES and contralateral NES were compared using independent sample t-test.
A total of 36 subjects (14 males and 22 females) were included in the study. The mean treatment duration for molar mesialization was 28.75±8.05months. The mean crown and root movements of mandibular second molar on ES were 10.94±1.25mm and 9.04mm±1.14mm, as compared to 0.91±1.01mm and 0.77±0.83mm on contralateral NES, respectively. The mean ABL and EARR at mandibular second molar were found to be significantly greater on the ES than the contralateral NES (P<0.001 and<0.05, respectively). A total of seven patients (19.4%) experienced ABL≥1mm on ES as compared to none in the contralateral NES. EARR of>2mm of at least one root was found in seven patients (19.4%) in ES as compared to four (11%) in contralateral NES.
There was small but statistically significant difference in the ABL and EARR of mesialized mandibular second molar at first molar ES as compared to the contralateral NES. For majority of patients this difference was small but few isolated cases experienced severe ABL and EARR.

OBJECTIVE: To evaluate the effect of micro-osteoperforations (MOPs) on the rate of orthodontic tooth movement (OTM) during en masse anterior retraction.
METHODS: Twenty patients were randomly allocated into experimental and control group of 10 each. In the control group, en masse retraction was performed with sliding mechanics with a coil spring. In the experimental group after alignment and levelling, MOPs were performed mesially and distally to all six anterior teeth in the interdental cortical region on the labial aspect of both arches. MOPs were performed at the beginning of space closure (T0) and 1 month after beginning of space closure (T1). En masse retraction was performed with sliding mechanics with a coil spring. Measurements were recorded on digital models made from scanned plaster casts at the beginning of space closure (T0) and monthly at each follow-up visit for the next 4 months (T1, T2, T3, T4). The monthly rate of OTM, the overall rate of OTM, and the difference between OTM in the MOP period (T0-T2) and post-MOP (T2-T4) period in the experimental and control group were evaluated. A visual analogue scale (VAS) was used to evaluate patients\' pain experience.
RESULTS: The overall rate of OTM was significantly greater in the experimental group for both arches in the MOP period (T0-T2) and also in the post-MOP period (T2-T4) as compared to the control group. Within the experimental group, the rate of OTM in the MOP period was significantly greater than in the post-MOP period, which in turn was greater than that of the control group. The patients reported only mild discomfort for 24 h after performing the MOPs, which then gradually decreased.
CONCLUSIONS: The use of MOPs is effective in increasing the rate of en masse tooth retraction in both the maxillary and the mandibular arch. The rate of tooth movement was greater even in the post-MOP period as compared to the control group.
UNASSIGNED: ZIELSETZUNG: Untersucht werden sollten die Auswirkungen von Mikro-Osteoperforationen (MOPs) auf die Geschwindigkeit der kieferorthopädischen Zahnbewegung (OTM) während einer En-masse-Retraktion im Frontzahnbereich.
METHODS: Zwanzig Patienten wurden randomisiert in eine Versuchs- und eine Kontrollgruppe mit jeweils 10 Patienten eingeteilt. In der Kontrollgruppe wurde die En-masse-Retraktion mit einer Gleitmechanik und einer Zugfeder durchgeführt. In der Versuchsgruppe wurden nach der Ausrichtung und Nivellierung MOPs mesial und distal an allen 6 Frontzähnen in der interdentalen Kortikalregion auf der labialen Seite beider Zahnbögen durchgeführt. Die MOPs wurden zu Beginn des Lückenschlusses (T0) und einen Monat nach Beginn des Lückenschlusses (T1) durchgeführt. Die En-masse-Retraktion wurde mit einer Gleitmechanik und einer Zugfeder durchgeführt. Die Messungen wurden auf digitalen Modellen aufgezeichnet, die aus eingescannten Gipsabdrücken zu Beginn des Lückenschlusses (T0) und monatlich bei jeder Nachuntersuchung in den nächsten 4 Monaten (T1, T2, T3, T4) erstellt wurden. Die monatliche OTM-Rate, die Gesamtrate der OTM und der Unterschied zwischen der OTM in der MOP-Periode (T0-T2) und in der Post-MOP-Periode (T2-T4) in der Versuchs- und in der Kontrollgruppe wurden bewertet. Zur Einschätzung des Schmerzempfindens der Patienten wurde eine visuelle Analogskala (VAS) verwendet.
UNASSIGNED: Die Gesamtrate der OTM war in der Versuchsgruppe für beide Zahnbögen in der MOP-Periode (T0-T2) und auch in der Post-MOP-Periode (T2-T4) im Vergleich zur Kontrollgruppe signifikant höher. In der Versuchsgruppe war die OTM-Rate in der MOP-Periode signifikant höher als in der Post-MOP-Periode, die wiederum höher war als die der Kontrollgruppe. Die Patienten berichteten über 24 h lang nach Durchführung der MOP andauernde, nur geringe, dann allmählich abnehmende Beschwerden.
UNASSIGNED: Die Anwendung von MOPs ist effektiv, um die Geschwindigkeit einer En-masse-Retraktion von Zähnen sowohl im Ober- als auch im Unterkiefer zu erhöhen. Die Geschwindigkeit der Zahnbewegung war sogar in der Zeit nach der MOP höher als in der Kontrollgruppe.

Maxillary frenectomy in children is a common procedure, but concerns about scar tissue affecting diastema closure prevent many clinicians from treating prior to orthodontics.
To determine if maxillary frenectomy is safe and if diastema size is affected by early treatment.
Paediatric patients with hypertrophic maxillary frena were treated under local anaesthesia with diode laser and CO2 laser. Diastema width was compared by calibrating and digitally measuring initial and postoperative intraoral photographs.
In total, 109 patients were included: 95 patients with primary dentition (39% male; mean age 1.9 years±1.5 years) and 14 with mixed dentition (43% male; mean age 8.1±1.3 years) with a mean follow-up of 18.0±13.2 months. No adverse outcomes were noted other than minor pain and swelling. In the primary dentition, a decrease in diastema width was observed in 94.7% with a mean closure of -1.4±1.0mm (range +0.7 to -5.1mm). In the mixed dentition, a decrease in diastema width was observed in 92.9% with a mean closure of -1.8±0.8mm (range 0 to -3.5mm). 74.5% of patients in the primary dentition and 75% of patients in the mixed dentition with preoperative diastema>2mm improved to<2mm width postoperatively.
Frenectomy is associated with cosmetic and oral hygiene benefits and when performed properly, does not impede diastema closure and may aid closure. Technique and case selection are critical to successful outcomes. IRB ethics approval was obtained from Solutions IRB protocol #2018/12/8, and this investigation was self-funded.

OBJECTIVE: To evaluate the effects of minimally invasive micro-osteoperforations (MOPs) on orthodontic tooth movement and pain.
METHODS: Prospective, split-mouth, randomized controlled trial.
METHODS: 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.
RESULTS: 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.
METHODS: Randomization was generated using a randomization table, and allocation was concealed in sequentially numbered, opaque, sealed envelopes.
METHODS: 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.
CONCLUSIONS: Short-term study, cast measurements done with digital callipers.
CONCLUSIONS: 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.
METHODS: The protocol was not published before trial commencement.
BACKGROUND: Trial was not registered.
BACKGROUND: The Australian Society of Orthodontists Foundation for Research and Education.

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.

OBJECTIVE: To evaluate the morphometric changes in maxillary and mandibular anterior alveolar bone after orthodontic treatment and retention for 18-24 months by cone-beam computed tomography (CBCT).
METHODS: Thirty-four adolescent patients (12 males and 22 females; mean age: 14.29 ± 1.24 years) diagnosed with bimaxillary dentoalveolar protrusion and with extractions of the 4 first premolars were included.
METHODS: The labial and lingual (palatal) alveolar bone thickness, height and root length of the maxillary and mandibular anterior teeth were assessed using CBCT imaging at the pre-treatment (T1), post-treatment (T2) and retention phases (T3). Voxel-based superimpositions of the T2 and T3 images were performed, and the distances of incisal and apical movement between T2 and T3 were measured to determine whether relapses occurred.
RESULTS: After orthodontic treatment, the labial and lingual (palatal) bone height decreased significantly (P < .05) and the labial thickness at the crestal (L1), midroot (L2), and apical levels (L3) had no significant change, while the lingual (palatal) bone thickness at all three levels decreased significantly (P < .05). After 18-24 months of retention, the lingual (palatal) height and the lingual (palatal) thickness at the crestal (L1) level increased significantly (P < .05). There were no obvious incisal and apical movements of the anterior teeth between T2 and T3 (P > .05), indicating that no relapses occurred.
CONCLUSIONS: Even though lingual (palatal) alveolar loss occurred due to the orthodontic treatment, the cervical alveolar bone seemed to recover over time. Therefore, appropriate camouflage treatment can be used in patients with bimaxillary dentoalveolar protrusion, and this treatment will not irreversibly deteriorate periodontal health and affect the orthodontic treatment stability.