جستجوی مقالات مرتبط با کلیدواژه « orthodontic tooth movement » در نشریات گروه « پزشکی »

These days minimally invasive micro‑osteoperforation (MOPs) has accelerated orthodontic tooth movement (OTM). However, there are some conflicting reports about their various impacts; hence, the present systematic review study aimed to evaluate the effect of MOP on root resorption, pulp vitality, and the biological changes of teeth subjected to OTM.

Search in electronic databases of English literature including PubMed, Scopus, Web of sciences, Cochrane, and Google scholar as well as a manual search was performed from 2013 to 2022. Most of the studies included in this article were randomized controlled trials.

From the total number of 321 found articles, 31 duplicated and 268 irrelevant articles were excluded regarding the defined inclusion and exclusion criteria. Consequently, 22 articles were subjected to the quality assessment process, and finally, 18 articles were selected for the review phase. Root resorption during tooth movement using the MOP approach was reported only in one study. Besides, except for two animal studies, all of the relevant included articles showed that MOPs significantly increased the expression of some inflammatory biomarkers known to recruit osteoclast precursors and increase the number of osteoclast cells. On the other hand, two animal studies showed no differences in osteoclast counts by using MOPs in comparison to their control groups, which was consequently the result of biologic variability between animal and human and also probably the small sample sizes of these two studies.

In this systematic review, according to the adverse effects of MOP on root resorption, one study showed higher levels of root resorption among patients undergoing MOP. However, this outcome was due to the different methods used to evaluate the effect of MOPs on root resorption. Moreover, a high certainty of evidence supports that MOP causes biological changes and an elevation in cytokines, chemokines, and other biomarkers that stimulates osteoclasts differentiation which in turn accelerate OTM. There was no change in pulp vitality status based on available evidence.

The aim of this research was to assess the effectiveness of eggshell–membrane (ESM)‑containing hyaluronic acid (HA) in the treatment of open gingival embrasure (OGE) following orthodontic tooth movement (OTM).

This study is an in vivo quasi experimental research. Atotal of 24 Cavia cobaya were equally divided into two groups, treatment (10% HA injection) and control (phosphate‑buffered saline [PBS]). A separator was inserted between mandibular incisors to induce an OGE. A volume of 20 µl of either PBS (n = 12) or ESM extract (n = 12) was locally injected within the interdental papilla. Decapitation of animals was made on day 1, 4, and 7 postinjection. The staining was done using hemotoxylin and eosin to observe angiogenesis and Mallory to observe the collagen density. Fourier‑transform infrared spectroscopy (FTIR) and thin‑layer chromatography (TLC) analysis were performed to detect the amount of HA available in ESM. The results were then compared with independent t‑tests and the Mann–Whitney test. The level of statistical significance was set at 0.05.

The FTIR and TLC analysis showed that HA was successfully identified in the ESM samples. Local injection of 10% HA induced an increase of angiogenesis compared to the control group on day 1 and 4 postinjection (P < 0.05). Significant differences (P < 0.05) were also noted in the collagen density and the growth of interdental papilla on day 4 and 7 postinjection.

ESM has the potential effect of regenerating the interdental papilla construction after OTM by increasing the collagen fiber density and inducing angiogenesis.

Many patients, particularly adults, may prefer clear aligner treatment due to its esthetics and ease of use. Some studies have shown that mechanical vibration can affect the rate of tooth movement and other aspects of orthodontic treatment. The purpose of this systematic review was to substantiate the effects of vibration as an adjunct to clear aligner treatment. A comprehensive search of the PubMed, Embase, Cochrane library, and Scopus and also hand searching of reference lists was conducted for finding published studies up to March 2021. Two authors reviewed the titles and abstracts independently to select relevant studies and the full texts where there was some skepticism. Seven papers were included in this study following removing duplicates and irrelevant studies, four of which were randomized controlled trial and three were retrospective studies. In the majority of studies, High‑Frequency Vibration (HFV) has shown to be effective in accelerating tooth movement and reducing the exchange interval of aligners. Little data have advocated that HFV can increase bone density, reduce pain or root resorption. It seems that HFV is more effective than low frequency vibration in patients treated with clear aligners. Based on a low level of certainty, HFV can increase the rate of tooth movement and decrease the exchange interval of clear aligners. Further investigation is necessary to clarify the effects of vibration on pain and discomfort, bone density, and root resorption.

Many patients, particularly adults, may prefer clear aligner treatment due to its esthetics and ease of use. Some studies have shown that mechanical vibration can affect the rate of tooth movement and other aspects of orthodontic treatment. The purpose of this systematic review was to substantiate the effects of vibration as an adjunct to clear aligner treatment. A comprehensive search of the PubMed, Embase, Cochrane library, and Scopus and also hand searching of reference lists was conducted for finding published studies up to March 2021. Two authors reviewed the titles and abstracts independently to select relevant studies and the full texts where there was some skepticism. Seven papers were included in this study following removing duplicates and irrelevant studies, four of which were randomized controlled trial and three were retrospective studies. In the majority of studies, High‑Frequency Vibration (HFV) has shown to be effective in accelerating tooth movement and reducing the exchange interval of aligners. Little data have advocated that HFV can increase bone density, reduce pain or root resorption. It seems that HFV is more effective than low frequency vibration in patients treated with clear aligners. Based on a low level of certainty, HFV can increase the rate of tooth movement and decrease the exchange interval of clear aligners. Further investigation is necessary to clarify the effects of vibration on pain and discomfort, bone density, and root resorption.

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).

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.

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.

Laser corticotomy can effectively accelerate canine retraction with no complications or discomfort for the patients.

IL-17 is reported to be associated with the pathophysiology of Orthodontic Tooth Movement (OTM) by affecting osteoclastogenesis.  To explore the changes of Th17 cytokines (IL-17, IL-23, and IL-27) expression and its correlation with receptor activator of nuclear factor kappa B ligand (RANKL) during orthodontic tooth movement.  Thirty patients who needed extraction of the first premolar during orthodontic treatment were included. The gingival crevicular fluid was sampled at the day of application (T0), one hour (T1), 24 hours (T2), one week (T3), four weeks (T4), and 12 weeks (T5) after the application of orthodontic force. The expression of Th17 cytokines and RANKL were measured by using enzyme-linked immunosorbent assay and, their correlations were assessed. The levels of IL-17A, IL-17F, IL-23, and IL-27 at both tension and pressure sides of studied teeth at T2-T4 were significantly higher compared with that of T0 and T1. Moreover, the expression of IL-27 at both tension and pressure sides of studied teeth at T2-T4 was significantly lower compared with that of T0 and T1. At T5, IL-17A, IL-17F, IL-23, and IL-27 returned to the baseline level. For the control group, the cytokines were notsignificantly different at various time points. The expression of IL-17A, IL-17F, and IL-23 was positively correlated with RANKL expression at T2-T4, whereas the IL-27 was negatively correlated with RANKL expression at T2-T4. This study provided preliminary evidence that Th17 cytokines may be involved in the regulation of OTM.

The aim of this study was to determine the effect of low‑level light therapy (LLLT) on orthodontic tooth movement (OTM) rate, heat shock protein 70 (HSP‑70) expression, and matrix metalloproteinase 8 (MMP‑8) expression.

In this experimental study twenty‑four male guinea pigs were randomly divided into three groups (n = 8): control group (K) without orthodontic force and LLLT; treatment group 1 (T1) with orthodontic force, and treatment group 2 (T2) with orthodontic force and LLLT. The labial surfaces of both maxillary central incisors in treatments groups were installed with single‑wing bracket before being inserted with close coil spring to give 10 g/cm2 orthodontic force. For the T2 group, 4 J/cm2 of LLLT was administered in the mesial‑distal and labial‑palatal regions for 3 min every day. On day 14, the gap between teeth was measured and immunohistochemistry staining was done to determine HSP‑70 and MMP‑8 expression. Data were analyzed using (IBM, New York, (ANOVA), followed by Turkey’s HSD test to determine the differences between groups. Nonnormal distributed data would be analyzed using Kruskal–Wallis test, followed by Mann–Whitney test with P < 0.05 being performed.

The gap between teeth in the T2 group was greater compared to T1 group (P = 0.00). However, there was a significant decrease of HSP‑70 and MMP‑8 expression in T2 group compared to T1 group in the tensile and compressive sides.

LLLT intervention during orthodontic treatment could accelerate OTM rate and decreased HSP‑70 and MMP‑8 expression both in tension and in compressive side. Thus, LLLT interventions can be used as adjuvant therapy to shorten orthodontic treatment duration.

To investigate the effect of cocoa on orthodontic tooth movement (OTM) rate, osteoprotegerin (OPG), and receptor activator of nuclear factor κ β ligand (RANKL) levels after OTM. A total of 24 Sprague-Dawley rats were included in the study. They were equally divided into two groups: cocoa and control. The upper incisors of all rats were subjected to 35 cN orthodontic force and moved distally with a stainless steel 3-spin coil spring. During OTM, the cocoa group was given 4.8 g of unsweetened cocoa once a day. At 4 subsequent time points (0, 1, 7, and 14 days), the OTM rate was determined by measuring the distance between the mesial tips using a digital caliper, while OPG and RANKL levels were examined based on their gingival crevicular fluid through specific enzyme-linked immunosorbent assay (ELISA). Data gathered were analyzed through independent t-test (P<0.05). The OTM rate of the cocoa group was significantly higher than that of the control group on days 1, 7, and 14 (P<0.05). ELISA analysis revealed that the OPG level was significantly lower on day 14. Furthermore, the RANKL level was significantly higher on days 0, 1, and 7 for the cocoa group compared with the control group (P<0.05). These results indicate that cocoa has the potential effect to modulate the OTM rate by inducing osteoclastogenesis, which suppresses the OPG level and stimulates the RANKL level, in rats.

The aim of this study was to investigate the crystal structure of mineral part in the Compact and Cancellous bones in different areas of alveolar bones.
In this study, 7 alveolar bone samples were prepared from buccal and distal plates of the jaws of three patients, and 4 samples from Cortical and Cancellous bone of two other patient's palate. After converting all the samples into powder, the samples were examined by using the X-RD method. Diffractogram of 1-7 samples were compared with each other and Diffractogram of 8-11 samples also were compared with each other too.
Comparing two corresponding points in the jaws the crystallinity degree in the mandible is higher than the maxilla. In comparison of two corresponding points in the maxilla and mandible degree of crystallinity and the crystalline hydroxyapatite on the right has been more than on the left. The amount of crystalline hydroxyapatite phase in females is more than males and crystallinity degree of this phase in males is more than females, and in younger people, the hydroxyapatite crystalline phase is more than others and crystallinity of this phase in older subjects is higher than others.
Tooth movement, despite the influence of the same forces, is faster on left side than the right side and is faster on maxilla than mandible. Tooth movement is faster in younger people than in older subjects.

Complications to force eruption of impacted teeth may arise from several reasons including ankylosis, dilaceration, and/or some barriers in the eruption pathway. Treatment time prolongation without obvious clinical progress gradually decreases the patient compliance. In this paper we present a non-conventional method to forced eruption of an impacted maxillary canine. A-21-year old girl presented with missing of teeth No 17, 12, 22, 27, 38, 37, 47, 48 and labially impaction of both maxillary canine was prepared for treatment through apically position flap for exposure of the both canines. Using standard edgewise 0.18 appliance and conventional elastic traction the right maxillary canine erupted to its normal position after about 18 months but the other tooth had not responded favorably to this technique. There was no signs of ankylosis, a titanium bone screw was placed in the labial cortical bone and mesial of the malposed canine. A spring is made of 0.017” × 0.025” SS wire with two helixes that delivered about 100 g force and 400 gr.mm activation moment to labial bracket on malposed canine crown. The force exerted on mini implant will be balanced with a force and moment on malposed tooth very similar to type IV Burston classification. After about 5 months the tooth had reached to its final occlusal position. The appliance used for this patient brought the impacted canine into the arch without any more force on the neighbor teeth. Two point contact of the spring arm by bending the wire over the head of the mini implant made it possible to apply buccolingual crown torque.

Statement of the Problem: Root resorption (RR) after orthodontic tooth movement (OTM) is known as a multifactorial complication of orthodontic treatments. Hormonal deficiencies and their effect on bone turnover are reported to have influences on the rate of tooth movement and root resorption. This study was designed to evaluate the effect of female and male steroid sex hormones on tooth movement and root resorption. Orthodontic appliances were placed on the right maxillary first molars of 10 ovariectomized female and 10 orchiectomized male Wistar rats as experimental groups and 10 female and 10 male healthy Wistar rats as control groups. NiTi closed-coil springs (9mm, Medium, 011"×.030", Ortho Technology®; Tampa, Florida) were placed between the right incisors and the first right maxillary molars to induce tipping movement in the first molars with the application of a 60g force. After 21 days, the rats were sacrificed and tooth movement was measured by using a digital caliper (Guanglu, China). Orthodontic induced root resorption (OIRR) was assessed by histomorphometric analysis after hematoxylin and eosin staining of sections of the mesial root. The rate of tooth movement was significantly higher in all female rats, with the root resorption being lower in the experimental group. The rate of tooth movement in experimental male rats was significantly higher than the control group (p= 0.001) and the rate of root resorption was significantly lower in the experimental group (p= 0.001). It seems that alterations in plasma levels of estrogen, progesterone, and testosterone hormones can influence the rate of OTM and RR. The acceleration in tooth movement increased OTM and decreased RR.

Basic fibroblast growth factor (bFGF) is a cytokine involved in angiogenesis, tissue remodeling and stimulation of osteoblasts and osteoclasts. The present study assesses the effects of a local injection of bFGF on the rate of orthodontic tooth movement. In this laboratory animal study, we randomly divided 50 rats into 5 groups of 10 rats each. Rats received 0.02 cc injections of the following doses of bFGF: group A (10 ng), group B (100 ng) and group C (1000 ng). Group D (positive control) received an orthodontic force and injection of 0.02 cc phosphate buffered saline whereas group E (negative control) received only the anesthetic drug. A nickel titanium spring was bonded to the right maxillary first molar and incisor. After 21 days, the rats were sacrificed and the distance between the first and second right molars was measured by a leaf gauge with 0.05 mm accuracy. ANOVA and Tukey’s HSD statistical tests were used for data analysis. The greatest mean value of orthodontic tooth movement was 0.7700 mm observed in group C followed by 0.6633 mm in group B, 0.5333 mm in group A, 0.2550 mm in group D and 0.0217 mm in group E. There was a significantly higher rate of tooth movement in the test groups compared to the control groups (p<0.05). Among the test groups, the rate of tooth movement in group C was significantly higher than group A (p<0.05). Weight changes after the intervention were not significant when compared to the baseline values, with the exception of group E (p>0.05). The effect of bFGF on the rate of tooth movement was dose-dependent. Injection of 1000 ng bFGF in rats showed the most efficacy.

This randomized trial was undertaken to investigate the effect of experimentally induced allergy on orthodontic induced root resorption. A total of 30 Wistar rats were divided randomly into test and control groups. Starting from the first 3 days, the rats in the test group were injected intra peritoneally by 2 mg ovalbumin as allergen and 0.5 mg Alume as adjuvant. Afterward only allergen was injected once a week. The control group was injected by normal saline. After 21 days, Wistar immunoglobulin E was measured and peripheral matured eosinophil was counted. A total of 50 g nickel titanium closed coil spring was ligated between right incisor and first molar. All animals were sacrificed after 14 days. The mesial root of the right and left first molar was dissected in a horizontalplane. The specimens were divided into four groups considering whether force and/or ovalbumin was applied or not. Root resorption was measured and compared among these groups. Repeated measures analysis of variance (ANOVA), and Bonferoni tests were used to analyze the data. The level of significance was determined at 0.05. In general, the differences were insignificant (P > 0.05). As the only exception, the group in which both ovalbumin and force were applied had significantly more root resorption than the group in which neither force nor ovalbumin was applied (P < 0.001). Allergy may increase the susceptibility to root resorption. Application of light force, periodical monitoring of root resorption and control of allergy are advisable.

Tramadol is an opioid agonist that has the potential of being abused. The aim of this study was to compare the effect of different doses of tramadol on orthodontic tooth movement (OTM) and bone resorption in rats. Forty‑two male rats were assigned randomly to two experimental groups and one control group. Nickel–titanium coil springs were used to exert orthodontic force. The rats in the control group and experimental group‑1, respectively, received a daily injection of 0.1 ml of normal saline and 10 mg/kg of tramadol for 14 days. The rats in experimental group‑2 received 10 mg/kg of the same drug on days 1-4, 20 mg/kg on days 5-8, 40 mg/kg on days 9-12 and 60 mg/kg on days 13 and 14. OTM was measured on days 4, 8, 12, and 14. At the end of the experimental period, the rats were sacrificed. Histological analysis was also performed to evaluate the number of osteoclasts, osteoblasts, and Howship’s lacunae. Statistical analysis with analysis of variance tests showed that the rats in experimental group‑2 had significantly decreased OTM compared with the other two groups (P < 0.05), whereas OTM for the rats in experimental group‑1 was comparable to that in the control group (P > 0.05). The histological evaluations did not show any significant difference among the groups (P > 0.05). The effect of tramadol hydrochloride on OTM depends on the dosage used. High doses of the drug reduce the extent of OTM significantly.

Tramadol is a synthetic analgesic of opioids which has more flexible mechanisms of action than typical opioids. Since it has been reported in previous study that typical opioids like morphine can affect the bone homeostasis, it is worthwhile to examine the effects of tramadol on tooth movement. In this study we investigated effects of tramadol on orthodontic tooth movement in rats. 30 male wistar rats were selected and received orthodontic appliance. 3 groups were designed based on the substance that they received daily injections of during a 2-week orthodontic treatment. 1. Control group with no injection.2.Control group with normal saline injection.3. the tramadol group. After the two-week treatment period the amount of tooth movement were measured in all the groups. Also the histological analysis was performed assessing the root resorption, osteoclasts numbers and bone resorption. The amount of tooth movement was not significantl in the tramadol group comparing to the other groups (P>0.05).The results of 3 histological parameters (amount of root resorption, osteoclastic numbers and bone resorption) were statistically insignificant (P>0.05). Tramadol as an atypical opioid does not interfere with the process of bone remodeling and tooth movement in rat. Tramadol does not affect osteoclastic activity and bone resorption and it does not cause to change the resulted root resorption either.

Obviously, long therapy time of orthodontic treatment and a number of its adverse effects, such as pain, rootresorption, enamel demineralization, periodontal disease, are the main reasons of complaints from patients. It is the first thing for an orthodontist to shorten the period of treatment and decrease the complications of orthodontic treatment as much as possible. The Hypothesis: We hypothesis Gonadotropin Releasing Hormone Agonists (GnRHa) and add-back therapy can create the “therapeutic window”, namely, the appropriate estrogen level and assuage the adverse effects of estrogen deficiency which should be avoided as much as possible. Evaluation of the Hypothesis: It is generally acknowledged that estrogen has direct regulating role in bone metabolism by acting on osteoblasts and osteoclasts. Estrogen deficiency can increase the rate of orthodontic tooth movement and also bring about some adverse effects. The appropriate estrogen level, which we call the “therapeutic window” in orthodontic treatment, can speed up the orthodontic tooth movement and eliminate the adverse effects as far as possible. GnRHa can be the maker of estrogen deficiency; meanwhile, add-back therapy can remove the adverse effects by estrogen deficiency. So, we believe that GnRHa plus add-back therapy could be a new adjuvant method of orthodontic treatment and be good for orthodontists and patients.

Developing new methods to enhance orthodontic tooth movement and shorten the duration of treatment has always been desired. However, to date, no therapies have been widely used in clinics. Recent studies and feedback information from patients have shown that drinking coffee may accelerate orthodontic tooth movement. The Hypothesis: Drinking coffee, as a daily habit of many people, can be an effective accelerator of tooth movement with little side effect for caffeine can break the calcium balance in bone tissue and directly inhibit the development of osteoblasts, leading to temporary decreased bone mineral density and consequently inducing faster orthodontic tooth movement. Evaluation of the Hypothesis: Much effort has been made to explore therapies to shorten orthodontic treatment period with limited success. Daily coffee consumption may be a promising approach to enhance orthodontic tooth movement for its reversible effect on bone mineral density and calcium balance.

The appearance of osteoclasts is the first step in orthodontic tooth movement. During orthodontic force application, the periodontal ligament (PDL) undergoes hyalinization. This tissue damage prevents the tooth from moving until the adjacent bone and necrotic tissue are removed by osteoclasts. There is a range of forces that produce the maximum rate of tooth movement. The purpose of this study was to compare the effect of different orthodontic forces on osteoclast numbers. Forty rats were randomly divided to 4 experimental groups. Appliance exerted 25gr in light, 40gr in moderate and 60gr in heavy group. There was not any appliance in control group. Animals were sacrified after 14 days and tissue samples were prepared. The mesial and distal surfaces of first upper molar and adjacent alveolar bone were studied. Osteoclast numbers, cementoclast numbers, root length, root resorption, depth and length of resorptive cavities, PDL. width in coronal-middle-apical, apical and coronal inflammation, bone resorption, necrotic bone and tooth movement were evaluated. Mesial and distal surfaces were also compared. In menial osteoclast numbers, depth of resorptive cavities, bone resorption, necrotic bone, PDL width and in distal apical inflammation, bone resorption, necrotic bone and PDL width were significant. Tooth movement was significantly different between all groups. (P<0.05) This data suggest that osteoclasts numbers are increased when force is increased. The magnitude of the orthodontic force is believed to be an important factor, not only for the magnitude of the tooth movement but also for any tissue damage.