Rate Of Orthodontic Tooth Movement Research Articles

Does long-term use of pain relievers have an impact on the rate of orthodontic tooth movement? A systematic review of animal studies

Pain relief drugs are used and misused widely and may theoretically affect the events leading to orthodontic tooth movement. To systematically investigate and appraise the quality of the available evidence regarding the effect of pain relief medications on the rate of orthodontic tooth movement. Search without restrictions in eight databases (including grey literature) and hand searching until October 2018. Animal controlled studies investigating the effect of pain relievers on the rate of orthodontic tooth movement. Following study retrieval and selection, relevant data were extracted and the risk of bias was assessed using the SYRCLE's risk of bias tool. Fourteen studies were finally identified, most of which at unclear risk of bias. Ibuprofen and loxoprofen did not show any significant effects on the rate of orthodontic tooth movement, whereas indomethacin, ketorolac, morphine, and high doses of etoricoxib were found to decrease it. Inconsistent or conflicting effects were noted after the administration of acetaminophen, acetylsalicylic acid, celecoxib, meloxicam, and tramadol. The quality of the available evidence was considered at best as low. Long-term consumption of pain relievers may affect the rate of orthodontic tooth movement. The orthodontist should be capable of identifying patients taking pain relievers independently of orthodontic treatment and consider the possible implications. PROSPERO (CRD42017078208).

Comparative study of the rate of tooth movement between corticotomy and piezocision to facilitate en masse retraction in bimaxillary protrusion

Objective: The aim of this study was to evaluate the rate of orthodontic tooth movement and the time needed for extraction space closure when corticotomy and piezocision were used to facilitate en-masse retraction in bimaxillary protrusion cases. Subjects and Methods: The sample of this study consisted of twenty subjects having Class I malocclusion with bimaxillary protrusion and requiring extraction of four first premolars and en-masse retraction of the anterior segments on both arches. The sample was randomly divided into two equal groups; group I:corticotomy was performed by using piezosurgery through flap reflection and group II: corticotomy was performed by using piezocision (flapless corticotomy). Study models were obtained just before surgery and in every month for 6 months after surgery to measure the rate of orthodontic tooth movement in both groups. After completing the en-masse retraction, the retraction time in months was recorded for the right and left sides and averaged. Results: Group I showed a statistically significant shorter retraction time than group II. Group I showed a statistically significant increase in the rate of tooth movement from the 2nd to the 5th month in the upper arch. For the lower arch, group I exhibited a significant increase in the rate of tooth movement in the 4th month. Conclusion: Corticotomy involving flap reflection showed a shorter retraction time and higher rates of tooth movement than piezocision during en-masse retraction.

Single Local Injection of Epigallocatechin Gallate-Modified Gelatin Attenuates Bone Resorption and Orthodontic Tooth Movement in Mice.

Osteoclastic bone resorption enables orthodontic tooth movement (OTM) in orthodontic treatment. Previously, we demonstrated that local epigallocatechin gallate (EGCG) injection successfully slowed the rate of OTM; however, repeat injections were required. In the present study, we produced a liquid form of EGCG-modified gelatin (EGCG-GL) and examined the properties of EGCG-GL with respect to prolonging EGCG release, NF-E2-related factor 2 (Nrf2) activation, osteoclastogenesis inhibition, bone destruction, and OTM. We found EGCG-GL both prolonged the release of EGCG and induced the expression of antioxidant enzyme genes, such as heme oxygenase 1 (Hmox1) and glutamate-cysteine ligase (Gclc), in the mouse macrophage cell line, RAW264.7. EGCG-GL attenuated intracellular reactive oxygen species (ROS) levels were induced by the receptor activator of nuclear factor-kB ligand (RANKL) and inhibited RANKL-mediated osteoclastogenesis in vitro. An animal model of bone destruction, induced by repeat Lipopolysaccharide (LPS)-injections into the calvaria of male BALB/c mice, revealed that a single injection of EGCG-GL on day-1 could successfully inhibit LPS-mediated bone destruction. Additionally, experimental OTM of maxillary first molars in male mice was attenuated by a single EGCG-GL injection on day-1. In conclusion, EGCG-GL prolongs the release of EGCG and inhibits osteoclastogenesis via the attenuation of intracellular ROS signaling through the increased expression of antioxidant enzymes. These results indicate EGCG-GL would be a beneficial therapeutic approach both in destructive bone disease and in controlling alveolar bone metabolism.

Influence of omega-3 fatty acid on orthodontic tooth movement in rats: A biochemical, histological, immunohistochemical and gene expression study.

The aim of this study was to investigate the effects of omega-3 fatty acids on orthodontic tooth movement. For this study, 56 12-week-old adult male Wistar albino rats from the Animal Laboratory at Adnan Menderes University, Faculty of Medicine, were used. Rats were randomly divided into seven groups (n=8 each): control group (without any treatment), tooth movement groups (three groups of animals with only tooth movement) and omega groups (three groups of animals with tooth movement and omega-3 administration). Omega-3 fatty acids were administered to the rats systemically during the tooth movement period. On the 3rd, 7th and 14thdays after the orthodontic tooth movement, the rats were sacrificed and biochemical, histological, immunohistochemical andgene expression examinations were performed. On the 14th experimental day, the amount of tooth movement in the omega groups was significantly lower than the tooth movement groups (P=0.012). Biochemical experimentsshowed that the omega groups had significantly lower total oxidant levels and higher total antioxidant levels compared to the tooth movement group on the 14th experimental day (P=0.001). The levels of RANKL, IL-6 and IL-1β in the omega groups were significantly lower than the tooth movement groups on all experimental days (P<0.05). Systemic administration of omega-3 fatty acids showed antioxidant and antiinflammatory effects and decelerate the orthodontic tooth movement.

Effects of vibrational devices on orthodontic tooth movement: A systematic review.

The aim of this systematic review was to investigate the ability of vibrational devices to increase the rate of orthodontic tooth movement or reduce pain associated with orthodontic treatment. An electronic search for relevant randomized controlled trials (RCTs) was conducted using Medline via OVID (January 1, 1966, through March 30, 2018), and EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials until August 2017. Hand searching of selected orthodontic journals was also undertaken. Through the electronic searches, 152 titles and abstracts were identified. From these, 10 articles were retrieved for review, and 4 of these met the inclusion criteria. Two additional articles were identified by hand searching. This resulted in 6 studies from 5 separate randomized controlled trials that were included in this systematic review. One RCT reported increased tooth movement with vibrational devices, but the other 4 RCTs reported no difference. Three studies investigated the effect of vibrational devices on pain reduction and found no effect. The ability of vibrational forces to increase the rate of tooth movement and reduce pain in orthodontic patients has been studied in several RCTs. The results from all but 1 of the included studies indicate no advantage from the use of vibrational devices during orthodontic treatment. Future studies should focus on total treatment duration, the mechanism by which vibration may speed up tooth movement, and the use of vibration with aligners. No funding was received for this review.

Evaluation of the Effect of Combined Low Energy Laser Application and Micro-Osteoperforations versus the Effect of Application of Each Technique Separately On the Rate of Orthodontic Tooth Movement.

AIM:The study was conducted to evaluate the effect of combined low energy laser application and Micro-Osteoperforations versus the effect of the application of each technique separately on the rate of orthodontic tooth movement.PATIENTS AND METHODS:Three parallel groups (each group contained 10 patients) were performed; Group A: In which one side was controlled side, and the other side received micro-osteoperforations (MOPs), Group B: In which one side was controlled side, and the other side received low-level laser therapy (LLLT), Group C: In which one side was controlled side, and the other side received both MOPs and LLLT.RESULTS:Significant statistical differences were obvious in the rate of canine retraction between each intervention and the control sides as following; the MOPs increased the rate of canine retraction by 1.6 fold more than the control side, LLLT increased the rate of canine retraction by 1.3 fold than the control side, and combination of both techniques resulted in an increase in the rate of canine retraction by 1.8 fold more than the control side.CONCLUSION:Combination of MOPs and LLLT proved to be more efficient regarding increasing the rate of canine retraction than the application of each technique separately.

Comparison of piezocision and discision methods in orthodontic treatment

BackgroundDiscision method may provide an alternative to the piezocision approach in accelerated orthodontic treatment. The purpose of this study was to investigate the efficacy of discision on accelerated orthodontic tooth movement in comparison to the piezocision method in moderate crowding Angle Class I malocclusions.MethodsThirty-five female individuals were included in this clinical study. The participants were classified into three groups as conventional fixed non-extraction orthodontic treatment only (OT, n = 14), piezocision in addition to fixed non-extraction orthodontic treatment (PG, n = 9), and discision in addition to fixed non-extraction orthodontic treatment (DG, n = 12). The piezocisions and discisions were performed 1 week after placement of bonding brackets. The patients were seen at 2–3 week-intervals. Initial Little’s irregularity index scores were recorded from dental casts. Periodontal parameters were measured initially, after the 1-month orthodontic treatment. Probing pocket depth, bleeding on probing, plaque index, and gingival index were recorded. Visual analog scale (VAS) was performed over the first month at different times following the bracket bonding for pain assessment. The total orthodontic treatment duration was noted.ResultsThe duration of orthodontic treatment was statistically decreased in PG and DG compared to OT (P = 0.003). There was no statistical difference between PG and DG in orthodontic treatment duration (P > 0.05). There was no statistical difference between the two experimental groups in terms of VAS and periodontal parameter values (P > 0.05).ConclusionsThis is the first clinical orthodontic study to assess the effect of discision on the rate of orthodontic tooth movement. Discision is comparable to piezocision in terms of tooth movement acceleration, pain level, and periodontal status. The discision seems to be effective in reducing the time of orthodontic treatment.

Comparison of rate of tooth movement and pain perception during accelerated tooth movement associated with conventional fixed appliances with micro-osteoperforations - a randomised controlled trial.

To investigate the influence of micro-osteoperforation (MOP) on rate of orthodontic tooth movement and pain perception with fixed appliances. 2 arm parallel randomized controlled trial with an allocation ratio of 1:1. The outpatient department of a dental college. 105 patients were screened, out of which 60 met the inclusion criteria and consented to participate; consisting of 33 females and 27 males requiring en-masse retraction following first premolar extractions. The experimental group consisted of patients bonded with a fixed appliance (Gemini 3M) who received MOP distal to canines throughout the period of retraction every 28 days. These were compared with a control group treated with identical brackets without MOP and were assessed for rate of tooth movement (canine retraction) and pain perception using a Visual Analogue Scale (VAS) of 10 mm. Prior to commencement, all baseline parameters were matched between the two groups (p>0.05). A statistically significant increase in rate of tooth movement in the MOP group (p<0.05). MOP appears to enhance the rate of tooth movement with no differences in pain perception.

A Novel Method to Quantify Longitudinal Orthodontic Bone Changes with In Vivo Micro-CT Data.

Orthodontic tooth movement (OTM) is the result of region-specific bone modeling under a load. Quantification of this change in the alveolar bone around a tooth is a basic requirement to understand the mechanism of orthodontics. The purpose of this study was to quantify subregional alveolar bone changes during orthodontic tooth movement with a novel method. In this study, 12 Sprague-Dawley (SD) rats were used as an orthodontic model, and one side of the first upper molar was used to simulate OTM. The alveolar bone around the mesial root was reconstructed from in vivo micro-CT images and separated from other parts of the alveolar bone with two semicylinder filters. The amount and rate of OTM, bone mineral density (BMD), and bone volume (BV) around the root were calculated and compared at 5 time points. The results showed that the amount of tooth movement, BMD, and BV can be evaluated dynamically with this method. The molar moved fastest during the first 3 days, and the rate decreased after day 14. BMD decreased from day 0 to day 14 and returned from day 14 to day 28. BV deceased from day 0 to day 7 and from day 14 to day 28. The method created in this study can be used to accurately quantify dynamic alveolar bone changes during OTM.

Low-level laser therapy increases interleukin-1β in gingival crevicular fluid and enhances the rate of orthodontic tooth movement.

The aim of this investigation was to evaluate the effects of low-level laser therapy on interleukin-1β (IL-1β) levels in gingival crevicular fluid and its correlation with orthodontic tooth movement. A split-mouth design was used in 10 subjects (6 female, 4 male) aged 14 to 25years, whose maxillary first premolars were extracted. A gallium-aluminum-arsenide semiconductor diode laser (wavelength, 940nm; energy density, 8J/cm2; power output, 100mW) delivered low-level laser therapy to the experimental canine undergoing distalization at 10 points. The control canine was distalized without low-level laser therapy. The experimental and control canines were distalized using a force of 150g provided by nickel-titanium closed-coil springs. Gingival crevicular fluid was collected at 5 time points from the control and experimental sides, and the levels of IL-1β were analyzed by enzyme-linked immuno-sorbent assay (ELISA). The distal movements of the maxillary canines were measured and compared. Increased levels of IL-1β were observed in the experimental canines compared with the control canines (P<0.001). Cumulative tooth movements over an 8-week experimental period were greater for the experimental canines (occlusogram and software, 4.450 and 4.4903mm, respectively) compared with the control canines (occlusogram and software, 2.025 and 2.0501mm, respectively). A positive correlation existed between the IL-1β levels and the amounts of tooth movement across all time intervals. In combination with light orthodontic force, application of low-level laser therapy increased the levels of IL-1β in gingival crevicular fluid and accelerated orthodontic tooth movement.

Effects of the highly COX-2-selective analgesic NSAID etoricoxib on the rate of orthodontic tooth movement and cranial growth

BackgroundNSAID analgesics have found widespread use in the treatment of pain, inflammation and fever. The highly COX-2-selective NSAID etoricoxib has shown a favorable side effect profile and excellent analgesic efficacy, particularly for dental and orthodontic pain, surpassing the current standard analgesic in orthodontics, acetaminophen. However, potential side effects on the rate of orthodontic tooth movement (OTM) and cranial growth, relevant for clinical usability during orthodontic treatment, have not yet been investigated. Material and methods40 male Fischer344 rats were randomly assigned to 4 groups (n=10) — controls receiving only 1.5ml tap water per day by oral gavage for a total of 5 weeks (1) as well as rats receiving an additional daily normal etoricoxib dosage of 7.8mg/kg for 3d (2) and 7d/week (3) and a high dosage of 13.1mg/kg for 7d/week (4) with serum bioavailability assessed by liquid chromatography–mass spectrometry. After one week of premedication, the first upper left molars (M1) were moved orthodontically in anterior direction for 4 weeks using a closed NiTi coil spring (0.25N) and OTM as well as sagittal cranial growth were quantified cephalometrically by CBCT imaging at the start and end of OTM. ResultsOTM, quantified as anterior metric tipping of M1, was significantly inhibited by about 33% only in rats receiving high-dose etoricoxib 7d/week (p=0.046) with a respective, but insignificant tendency also detectable for the normal dosages, whereas sagittal cranial growth was by tendency slightly increased with rising etoricoxib dosages, reflected by corresponding steady-state serum concentrations, confirming etoricoxib bioavailability. ConclusionsAn etoricoxib-induced clinically relevant deceleration of OTM is not to be expected at dosage regimens used in clinical practice to treat dental or orthodontic pain in contrast to a continuously administered high dosage. Due to its favorable side effect profile and higher analgesic efficiency regarding dental and orthodontic pain, etoricoxib should be a clinically valid alternative to the current standard orthodontic analgesic acetaminophen with its associated higher risk profile.

Piezoelectric Tooth Aligner for Accelerated Orthodontic Tooth Movement.

In this paper, we propose a device that can induce vibration to potentially accelerate the rate of orthodontic tooth movement and thus reduce the duration of the orthodontic treatment. This is accomplished by harmonically exciting a polyvinylidene fluoride (PVDF) piezoelectric actuators to generate vibration and hence generate cyclic loading at 30 Hz. PVDF is a popular piezoelectric polymer because of its high flexibility, biocompatibility, and low cost. Generally, application of cyclic loading (vibration) reverses bone loss, stimulates bone mass, induces cranial growth, and accelerates tooth movement. This reduce the pain experience and discomfort associated with the orthodontic treatment and also enhances the patient compliance with the treatment. Vibration has the advantage of minimal side effects in comparison to medicinal treatments. The device is attached to either a positioner or teeth aligner. The main advantage of this work is that the device can be adjusted and repositioned in a different location of the teeth aligner. We propose one device that incorporates vibration, harmonic function generation, and the housing unit for the battery and processor. Current approaches require an external device, which is relatively cumbersome to the patient. Theoretical analysis based on the distributed parameter model is utilized to justify our claim. Piezoelectric actuation behavior is simulated using Finite Element Analysis.

The effect of autologous leukocyte platelet rich fibrin on the rate of orthodontic tooth movement: A prospective randomized clinical trial.

Objective:The aim of this study was to evaluate the effect of LPRF, placed in extraction sockets, on orthodontic tooth movement (OTM).Materials and Methods:Thirty extraction sockets from eight patients (five males, three females, with a mean age of 17.37 years; range 12–25 years) requiring extraction of first premolars based on their orthodontic treatment plan participated in this split-mouth clinical trial. In one randomly selected quadrant of each jaw, the extraction socket was preserved as the experimental group by immediate placement of LPRF in the extraction socket. The other quadrant served as the control group for secondary healing. Immediately, the teeth adjacent to the defects were pulled together by a NiTi closed-coil spring with constant force. A piece of 0.016 × 0.022-inch stainless steel wire was used as the main arch wire. The amount of OTM was measured on the study casts at eight time points with 2-week intervals for 3 months. Analysis of random effect model was performed for the purpose of comparison between the experimental and control groups.Results:According to the random effect model, a statistically significant difference was found between the experimental and control group in rate of OTM (P = 0.006).Conclusion:According to the results, application of LPRF, as an interdisciplinary approach combining orthodontics and surgery, may accelerate OTM, particularly in extraction cases.

Effects of Transmucosal Thyroxine Administration on the Tooth Movement in an Animal Model

Objective The aim of this study was to investigate the effects of transmucosal administration of thyroxine on the tooth movement and osteoclastic activity in Beagle dogs. Materials and Methods Eight Beagles were randomly divided into control group (n = 4) and thyroxine group (4-week group, n = 2 and 8-week group, n = 2). Buttons were bonded on the labial surfaces of the second premolar and anchorage teeth. Nickel-titanium closed-coil springs were connected. In the thyroxine group, thyroxine tablets were bonded to the hooks attached to the second premolar. Results The mean rate of orthodontic tooth movement (OTM) in the thyroxine group was slightly higher than that in the control group. Microscopic evaluation showed that the number of osteoclasts in the thyroxine group significantly increased. Conclusion The protocol for transmucosal administration of thyroxine could not significantly accelerate OTM. An increase in the number of osteoclasts was observed through microscopic evaluation during the 4th week.

Vibration paradox in orthodontics: Anabolic and catabolic effects.

Vibration in the form of High Frequency Acceleration (HFA) is anabolic on the craniofacial skeleton in the absence of inflammation. Orthodontic forces trigger an inflammation-dependent catabolic cascade that is crucial for tooth movement. It is unknown what effect HFA has on alveolar bone if applied during orthodontic treatment. The objectives of this study are to examine the effect of HFA on the rate of tooth movement and alveolar bone, and determine the mechanism by which HFA affects tooth movement. Adult Sprague Dawley rats were divided to control, orthodontic force alone (OTM), and different experimental groups that received the same orthodontic forces and different HFA regimens. Orthodontic tooth movement was assessed when HFA parameters, frequency, acceleration, duration of exposure, and direct or indirect application were varied. We found that HFA treatment significantly enhanced the inflammation-dependent catabolic cascade during orthodontic tooth movement. HFA treatment increased inflammatory mediators and osteoclastogenesis, and decreased alveolar bone density during orthodontic tooth movement. Each of the HFA variables produced significant changes in the rate of tooth movement and the effect was PDL-dependent. This is the first report that HFA enhances inflammation-dependent catabolic cascades in bone. The clinical implications of our study are highly significant, as HFA can be utilized to enhance the rate of orthodontic tooth movement during the catabolic phase of treatment and subsequently be utilized to enhance retention during the anabolic remodeling phase after orthodontic forces are removed.

Effects of different force magnitudes on corticotomy-assisted orthodontic tooth movement in rats.

To investigate the effects of light and heavy forces with corticotomy on tooth movement rate, alveolar bone response, and root resorption in a rat model. The right and left sides of 40 male Wistar rats were randomly assigned using the split-mouth design to two groups: light force with corticotomy (LF) and heavy force with corticotomy (HF). Tooth movement was performed on the maxillary first molars using a nickel-titanium closed-coil spring delivering either 10 g (light force) or 50 g (heavy force). Tooth movement and alveolar bone response were assessed by micro-computed tomography (micro-CT) at day 0 as the baseline and on days 7, 14, 21, and 28. Root resorption was examined by histomorphometric analysis at day 28. Micro-CT analysis showed a significantly greater tooth movement in the HF group at days 7 and 14 but no difference in bone volume fraction at any of the observed periods. Histomorphometric analysis found no significant difference in root resorption between the LF and HF groups at day 28. Heavy force with corticotomy increased tooth movement at days 7 and 14 but did not show any difference in alveolar bone change or root resorption.

Effects of loxoprofen on the apical root resorption during orthodontic tooth movement in rats.

Studies have revealed that severe apical root resorption during tooth movement is caused by the noninfective inflammatory reaction of apical root tissues. We hypothesized that loxoprofen can suppress apical root resorption during tooth movement. Cyclic tensile force (CTF) of 10 kPa was applied to the human pulp cells for 48 hours by the Flexcell Strain Unit. Loxoprofen (10 and 100 μM) was added to the culture cells, and expression of cyclooxygenase (COX)-1, COX-2, interleukin (IL)-1β, receptor activator of nuclear factor kappa-B ligand (RANKL), tumor necrosis factor (TNF)-α, and macrophage colony-stimulating factor (M-CSF) were examined. To determine the effects of loxoprofen sodium on apical root reabsorption during tooth movement, the upper first molars of 7-week-old rats were subjected to mesial movement by 10g force for 30 days with or without the oral administration of loxoprofen. Gene expression and protein concentration of COX-1, COX-2, IL-1β, TNF-α, RANKL and M-CSF were significantly higher in the CTF group than in the control group. However, these levels were decreased by loxoprofen administration. After orthodontic tooth movement, the expression of IL-1β, TNF-α, RANKL and M-CSF decreased in the loxoprofen group than in the control group by immunohistochemical staining. In comparison to control group, less number of odontoclasts and a decrease in the amount of apical root resorption was observed in the loxoprofen group. Many osteoclasts became visible on the pressure side of the alveolar bone in the both groups, and the amount of tooth movement did not show a significant difference. These findings demonstrate that severe apical root resorption may be suppressed by loxoprofen administration, without a disturbance of tooth movement.

Effect of low level laser and low intensity pulsed ultrasound therapy on bone remodeling during orthodontic tooth movement in rats

BackgroundQuality bone regeneration, which leads to the improvement of bone remodeling, is essential for orthodontic treatment. In order to improve bone regeneration and increase the amount of tooth movement, different techniques have been implemented. The object of this study is to compare the effects of low-level laser therapy (LLLT), low-intensity pulsed ultrasound (LIPUS), and their combination on bone remodeling during orthodontic tooth movement.MethodsEighty (80) male, 6-week-old Sprague Dawley rats were grouped in to four groups, the first group was irradiated with (940 nm) diode laser, second group with LIPUS, and third group with combination of both LLLT and LIPUS. A forth group used was a control group in an incomplete block split-mouth design. The LLLT and LIPUS were used to treat the area around the moving tooth once a day on days 0–7, then the experiment was ended in each experimental endpoint (1, 3, 7, 14, and 21 days). For amount of tooth movement, models were imaged and analyzed. Histological examination was performed after staining with (hematoxylin and eosin) and (alizarin red and Alcian Blue) stain. One step reverse transcription-polymerase chain reaction RT-PCR was also performed to elucidate the gene expression of RANK, RANKL, OPG, and RUNX-2.ResultsThe amount of tooth movement, the histological bone remodeling, and the RT-PCR were significantly greater in the treatment groups than that in the control group. Among the treatment groups, the combination group was the highest and the LIPUS group was the lowest.ConclusionThese findings suggest that LLLT and LIPUS can enhance the velocity of tooth movement and improve the quality of bone remodeling during orthodontic tooth movement.

Does common prescription medication affect the rate of orthodontic tooth movement? A systematic review.

As the taking of any medication may theoretically affect the complex pathways responsible for periodontal tissue homeostasis and the events leading to orthodontic tooth movement, it is considered important for the orthodontist to be able to identify prospective patients' history and patterns of pharmaceutical consumption. To systematically investigate and appraise the quality of the available evidence regarding the effect of commonly prescribed medications on the rate of orthodontic tooth movement. Search without restrictions in eight databases and hand searching until June 2017. Controlled studies investigating the effect of commonly prescribed medications with emphasis on the rate of orthodontic tooth movement. Following study retrieval and selection, relevant data was extracted and the risk of bias was assessed using the SYRCLE's Risk of Bias Tool. Twenty-seven animal studies, involving various pharmacologic and orthodontic interventions, were finally identified. Most studies were assessed to be at unclear or high risk of bias. The rate of orthodontic tooth movement was shown to increase after the administration of diazepam, Vitamin C and pantoprazole, while simvastatin, atorvastatin, calcium compounds, strontium ranelate, propranolol, losartan, famotidine, cetirizine, and metformin decreased the rate of orthodontic tooth movement. No interference with the rate of orthodontic tooth movement was reported for phenytoin, phenobarbital and zinc compounds, whereas, inconsistent or conflicting effects were noted after the administration of L-thyroxine, lithium compounds, fluoxetine and insulin. The quality of the available evidence was considered at best as low. Commonly prescribed medications may exhibit variable effects on the rate of orthodontic tooth movement. Although the quality of evidence was considered at best as low, raising reservations about the strength of the relevant recommendations, the clinician should be capable of identifying patients taking medications and should take into consideration the possible implications related to the proposed treatment. PROSPERO (CRD42015029130).

Decreased bone density induced by antiepileptic drugs can cause accelerated orthodontic tooth movement in male Wistar rats

The aim of the present study was to evaluate the effect of the carbamazepine and valproic acid on orthodontic tooth movement in male Wistar rats. Evaluation of tooth movement after 21 days of drugs infusion was carried out by feeler gauge. Bone densitometry on lateral cephalograms was conducted on days 1 and 21. After dissection of the maxillae, histologic parameters were evaluated. Orthodontic tooth movement was accelerated in experimental groups rather than controls. Optical density was significantly increased in these groups. In histologic sections, mesioapical portion of the PDL (Periodontal Ligament) was wider in experimental groups. Also, distoapical portion of the PDL was wider only in valproic acid group. Valproic acid and carbamazepine can decrease the bone density which may induce the accelerated orthodontic tooth movement in rats.