A needle in a haystack: Report of a retained archwire fragment in the pterygomandibular space.

This clinical report describes a retained archwire fragment, discovered during a new-patient examination of a young woman seeking orthodontic retreatment. The diagnostic process, care coordination, and patient management decisions are discussed, along with a brief exploration of clinical considerations associated with this incident. A suggested emergency prevention and response protocol is also presented.

Is Low-Level Laser Therapy an Effective Method to Alleviate Pain Induced by Active Orthodontic Alignment Archwire? A Randomized Clinical Trial.

OBJECTIVE: The aim of this study is to assess if low-level laser therapy (LLLT) alleviates pain after the placement of orthodontic alignment archwire and if there could be a specific indication for the usage of LLLT according to the amount of dental crowding. MATERIALS AND METHODS: Ninety subjects were included and randomly assigned to the tested group (orthodontic treatment and LLLT), placebo group (orthodontic treatment and simulated LLLT), and control group (orthodontic treatment only). Inclusion criteria are age between 13 and 30 years, completely erupted mandibular teeth, and lower crowding of ≥3 mm. Exclusion criteria are spaces or diastema in the lower arch, ectopic teeth, treatment plan including extractions or the use of auxiliary devices, and previous orthodontic treatment. Patients reported the pain experienced by using a numeric rating scale, ranging from 0 to 10, at specific time intervals, that is, 2 hours, 6 hours, 24 hours, and from day 2 to 7. Kruskal-Wallis H Test was used to assess differences in the maximum pain and pain experienced at each time interval among the three groups and in the maximum pain reported among subjects with different degree of crowding. RESULTS: The final sample consisted of 84 patients, 41 male and 43 female patients, with a mean age of 16.5 ± 2.8 years. The pain experienced at each time interval and the maximum pain score were significantly lower in the tested group, whereas no differences were found between control and placebo groups. Moreover, no differences were found in the pain experienced among subjects with mild, moderate, and severe incisor crowding in all groups. CONCLUSIONS: LLLT is effective in alleviating the intensity and duration of pain experienced by patients after the engagement of alignment archwire. However, there is no specific indication for the usage of LLLT according to the amount of crowding.

Initial arch wires used in orthodontic treatment with fixed appliances.

BACKGROUND: Initial arch wires are the first arch wires to be inserted into the fixed appliance at the beginning of orthodontic treatment and are used mainly for the alignment of teeth by correcting crowding and rotations. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause least amount of root resorption and pain during the initial aligning stage of treatment. This is an update of the review entitledInitial arch wires for alignment of crooked teeth with fixed orthodontic braces, which was first published in 2010. OBJECTIVES: To assess the effects of initial arch wires for the alignment of teeth with fixed orthodontic braces, in terms of the rate of tooth alignment, amount of root resorption accompanying tooth movement, and intensity of pain experienced by patients during the initial alignment stage of treatment. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 5 October 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 9), MEDLINE Ovid (1946 to 5 October 2017), and Embase Ovid (1980 to 5 October 2017. The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of initial arch wires to align teeth with fixed orthodontic braces. We included only studies involving participants with upper or lower, or both, full arch fixed orthodontic appliances. DATA COLLECTION AND ANALYSIS: Two review authors were responsible for study selection, 'Risk of bias' assessment and data extraction. We resolved disagreements by discussion between the review authors. We contacted corresponding authors of included studies to obtain missing information. We assessed the quality of the evidence for each comparison and outcome as high, moderate, low or very low, according to GRADE criteria. MAIN RESULTS: For this update, we found three new RCTs (228 participants), bringing the total to 12 RCTs with 799 participants. We judged three studies to be at high risk of bias, and three to be at low risk of bias; six were unclear. None of the studies reported the adverse outcome of root resorption. The review assessed six comparisons.1. Multistrand stainless steel versus superelastic nickel-titanium (NiTi) arch wires. There were five studies in this group and it was appropriate to undertake a meta-analysis of two of them. There is insufficient evidence from these studies to determine whether there is a difference in rate of alignment between multistrand stainless steel and superelastic NiTi arch wires (mean difference (MD) -7.5 mm per month, 95% confidence interval (CI) -26.27 to 11.27; 1 study, 48 participants; low-quality evidence). The findings for pain at day 1 as measured on a 100 mm visual analogue scale suggested that there was no meaningful difference between the interventions (MD -2.68 mm, 95% CI -6.75 to 1.38; 2 studies, 127 participants; moderate-quality evidence).2. Multistrand stainless steel versus thermoelastic NiTi arch wires. There were two studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from the studies to determine whether there is a difference in rate of alignment between multistrand stainless steel and thermoelastic NiTi arch wires (low-quality evidence). Pain was not measured.3. Conventional NiTi versus superelastic NiTi arch wires. There were three studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is any difference between conventional and superelastic NiTi arch wires with regard to either alignment or pain (low- to very low-quality evidence).4. Conventional NiTi versus thermoelastic NiTi arch wires. There were two studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is a difference in alignment between conventional and thermoelastic NiTi arch wires (low-quality evidence). Pain was not measured.5. Single-strand superelastic NiTi versus coaxial superelastic NiTi arch wires. There was only one study (24 participants) in this group. There is moderate-quality evidence that coaxial superelastic NiTi can produce greater tooth movement over 12 weeks (MD -6.76 mm, 95% CI -7.98 to -5.55). Pain was not measured.6. Superelastic NiTi versus thermoelastic NiTi arch wires. There were three studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is a difference in alignment or pain between superelastic and thermoelastic NiTi arch wires (low-quality evidence). AUTHORS' CONCLUSIONS: Moderate-quality evidence shows that arch wires of coaxial superelastic nickel-titanium (NiTi) can produce greater tooth movement over 12 weeks than arch wires made of single-strand superelastic NiTi. Moderate-quality evidence also suggests there may be no difference in pain at day 1 between multistrand stainless steel arch wires and superelastic NiTi arch wires. Other than these findings, there is insufficient evidence to determine whether any particular arch wire material is superior to any other in terms of alignment rate, time to alignment, pain and root resorption.

Evaluation of the Effects of Fluoride Prophylactic Agents on Mechanical Properties of Nickel Titanium Wires using Scanning Electron Microscope.

INTRODUCTION: Orthodontic treatment these days is increasing in demand, and therefore, it is relatively imperative for the orthodontist to prescribe the use of fluoride-containing products, such as mouthwashes and gels, to help prevent dental caries and maintain healthy oral health. The aim of the study was to assess and evaluate the effects of fluoride prophylactic agents on mechanical properties of nickel titanium (NiTi) wires during orthodontic treatment using scanning electron microscope (SEM). MATERIALS AND METHODS: We used the commercially available round preformed NiTi orthodontic archwire (3M company) and three different mouthwash solutions, i.e., Phos-Flur gel (1.1% sodium acidulated phosphate fluoride, APF, 0.5% w/v fluoride, pH = 5.1; Colgate Oral Pharmaceuticals) and Prevident 5000 (1.1% sodium fluoride neutral agent, 0.5% w/v fluoride, pH = 7; Colgate Oral Pharmaceuticals). All the specimens were subjected to a three-point bending test on a universal testing machine. To observe the surface morphological changes, one wire from each group was randomly selected and observed under a SEM. RESULTS: It was observed that there was not much difference in the values of both modulus of elasticity and yield strength obtained after loading of stress on the wires in all the three experimental conditions. A significant difference in both modulus of elasticity and yield strength was observed during unloading of stress. Further, when the surface characteristics were observed for all the specimens using SEM images, it was observed that NiTi wires treated with Phos-Flur showed large surface defects which appeared as round, pitted areas depicting corrosion, numerous white inclusions, and overall damaged surface structure of the wire as compared with the control. CONCLUSION: Thus, fluoridated mouthwashes are essential to maintain good oral hygiene and decrease instance of caries in patients undergoing orthodontic treatment. The prophylactic usage of topical fluoride agents on NiTi wire seems to diminish the mechanical properties of the orthodontic wire that could significantly affect future treatment outcomes. CLINICAL SIGNIFICANCE: It has been proved that fluoride mouthwashes/gels do affect the structural surface qualities and strength of wires used during the orthodontic treatment irrespective of the composition of the wires. Therefore, it is the responsibility of the clinician to prescribe these prophylactic agents carefully while keeping in mind their pH so that the overall result of the treatment may not be hampered and delayed due to change in properties of the wires used.

The Efficacy of Low-level Laser Therapy on Pain caused by Placement of the First Orthodontic Archwire: A Clinical Study.

Aim: This study was conducted to clinically evaluate the effect of low-level laser therapy (LLLT) as a method of reducing pain reported by patients after placement of their first orthodontic archwires. Materials and methods: A sample of 10 patients with an age group of 12 to 26 years with moderate-to-severe anterior crowding was selected. Each patient was assigned to an experimental group (left quadrant with laser therapy) and a control group (right quadrant with no laser therapy). Low-level laser therapy was given immediately after the placement of initial archwire. All patients were instructed to fill up a survey form at home over the next 7 days. Results: The results revealed that the average onset of pain in the experimental group (16.10 hours) was significantly reduced when compared with the control group (3.10 hours). The most painful day was similar for both the groups. The pain ceased much sooner in the experimental group than in the control group. The intensity of pain was lesser in the experimental group when compared with the control group. Conclusion: Low-level laser therapy was an effective and noninvasive method for controlling pain in orthodontic patients after receiving their first archwires. The duration and intensity of pain reduced with the application of LLLT Clinical significance: Pain reduction during orthodontic procedures. Keywords: Low-level laser therapy, Nickel-titanium wires, Orthodontic pain.

Effectiveness of pulsed electromagnetic field for pain caused by placement of initial orthodontic wire in female orthodontic patients: A preliminary single-blind randomized clinical trial.

INTRODUCTION: The purpose of this 2-arm parallel trial was to assess the effects of pulsed electromagnetic field (PEMF) on the reduction of pain caused by initial orthodontic tooth movement. METHODS: Thirty-three female patients (mean age, 16.8 ± 3.8 years) who began orthodontic treatment using fixed appliances were examined. In the pilot study, male patients were less likely to use the PEMF device (epatchQ; Speed Dental, Seoul, Korea) and answer a survey consistently, so eligibility criteria were female patients who were periodontally and systemically healthy at the initiation of treatment and had no history of dental pain in the prior 2 weeks or who used no medications (anti-inflammatory or analgesic drugs) during the experiment period. Each patient had brackets bonded on the maxillary teeth, and a 0.014-in nickel-titanium archwire was tied with elastomeric rings. Their maxillary arches were randomly divided into left and right sides in a split-mouth design: a normal PEMF device (experimental group) was used on 1 side, and a PEMF device with an inversely inserted battery (placebo group) was used on the opposite side of the arch for 7 hours on 3 consecutive nights. A Google survey link was sent to the patients' mobile phones via text message, and they were instructed to record their current pain on the survey. The survey was sent a total of 6 times after insertion of the initial archwire at 0 (T0), 2 (T1), 6 (T2), 24 (T3), 48 (T4), and 72 (T5) hours. Patients recorded the degree of pain in resting and clenching states using a numeric rating scale (NRS) from 1 (no pain) to 10 (worst pain). PEMF devices were used after T2. Generalized linear mixed models, along with ancillary pairwise analyses, were used to model and evaluate the differences in pain reported over 72 hours. RESULTS: The NRS scores did not differ across the groups during the before-PEMF phase for resting (mean difference, -0.07; 95% confidence interval [CI], -0.73 to 0.59; P = 0.842) and clenching (mean difference, -0.28; 95% CI, -1.11 to 0.56, P = 0.513). During the after-PEMF phase, NRS scores in the experimental group were significantly lower than those in the placebo group during both resting (mean difference, -1.46; 95% CI, -2.06 to -0.85; P = <0.001) and clenching (mean difference, -1.88; 95% CI, -2.74 to -1.02, P = <0.001). The NRS scores did not differ across the groups during the before-PEMF phase for either state but were significantly lower in the experimental group than in the placebo group at T3, T4, and T5 (P <0.01). The average NRS score in the clenching state was significantly greater than in the resting state. CONCLUSIONS: PEMF was effective in reducing orthodontic pain caused by initial archwire placement. REGISTRATION: The trial was not registered. PROTOCOL: The protocol was not published before trial commencement.

Cytotoxic outcomes of orthodontic bands with and without silver solder in different cell lineages.

INTRODUCTION: The safety of orthodontic materials is a matter of high interest. In this study, we aimed to assess the in-vitro cytotoxicity of orthodontic band extracts, with and without silver solder, by comparing the viability outcomes of the HaCat keratinocytes, the fibroblastic cell lineages HGF and MRC-5, and the kidney epithelial Vero cells. METHODS: Sterilized orthodontic bands with and without silver solder joints were added to culture media (6 cm2/mL) and incubated for 24 hours at 37°C under continuous agitation. Subsequently, the cell cultures were exposed to the obtained extracts for 24 hours, and an assay was performed to evaluate the cell viability. Copper strip extracts were used as positive control devices. RESULTS: The extracts from orthodontic bands with silver solder joints significantly reduced the viability of the HaCat, MRC-5, and Vero cell lines, whereas the viability of HGF was not altered by this material. Conversely, the extracts of orthodontic bands without silver solder did not significantly modify the viability index of all evaluated cell lines. CONCLUSIONS: Except for HGF fibroblasts, all tested cell lines showed decreased viability percentages after exposure to extracts of orthodontic bands containing silver solder joints. These data show the relevance of testing the toxicity of orthodontic devices in different cell lines.

Comparative Evaluation of Myeloperoxidase Enzymatic Activity in Gingival Crevicular Fluid of Subjects having Orthodontic Treatment by Different Aligning Arch Wires.

INTRODUCTION: There exist a number of factors that affect the outcome of orthodontic treatment. These factors can be assessed by various gingival markers. One such maker is myeloperoxidase (MPO). Hence, we planned the present study to assess and compare the MPO activity in the gingival crevicular fluid (GCF) of subjects undergoing orthodontic treatment by different aligning arch wires. MATERIALS AND METHODS: The present study included assessment of patients who underwent orthodontic treatment for crowding of anterior teeth. Diagnostic cast models of all the subjects were made for recording the irregularity index. All the subjects were randomly divided into three study groups with 15 patients in each group based on the type of nickel-titanium (NiTi) arch wires used. A collection of GCF samples was done in all the patients at various time intervals and it was sent to the laboratory for assessment of MPO activity. Activity of the MPO enzyme was expressed in terms of number of units per 100 µL. All the results obtained were compiled and analyzed by Statistical Package for the Social Sciences (SPSS) software. RESULTS: We observed that nonsignificant results were obtained while comparing the mean age and mean gingival score in all the study groups. However, significant results were obtained on comparing the mean MPO enzymatic activity in all the study groups at different time intervals. CONCLUSION: Both superelastic NiTi and heat-activated NiTi generate optimal forces, which are necessary for higher metabolic response of the periodontal ligament. CLINICAL SIGNIFICANCE: In the intimal stages of orthodontic treatment, both superelastic NiTi and heat-activated NiTi wires are superior in leveling and aligning the crowded teeth.

Ion Release and Galvanic Corrosion of Different Orthodontic Brackets and Wires in Artificial Saliva.

INTRODUCTION: To investigate the galvanic corrosion of brackets manufactured by four different companies coupled with stainless steel (SS) or nickel-titanium (NiTi) wires in an artificial saliva solution. MATERIALS AND METHODS: A total of 24 mandibular central incisor Roth brackets of four different manufacturers (American Orthodontics, Dentaurum, Shinye, ORJ) were used in this experimental study. These brackets were immersed in artificial saliva along with SS or NiTi orthodontic wires (0.016'', round) for 28 days. The electric potential difference of each bracket/ wire coupled with a saturated calomel reference electrode was measured via a voltmeter and recorded constantly. Corrosion rate (CR) was calculated, and release of ions was measured with an atomic absorption spectrometer. Stereomicroscope was used to evaluate all samples. Then, samples with corrosion were further assessed by scanning electron microscope and energy-dispersive X-ray spectroscopy. Two-way analysis of variance was used to analyze data. RESULTS: Among ions evaluated, release of nickel ions from Shinye brackets was significantly higher than that of other brackets. The mean potential difference was significantly lower in specimens containing a couple of Shinye brackets and SS wire compared with other specimens. No significant difference was observed in the mean CR of various groups (p > 0.05). Microscopic evaluation showed corrosion in two samples only: Shinye bracket coupled with SS wire and American Orthodontics bracket coupled with NiTi wire. CONCLUSION: Shinye brackets coupled with SS wire showed more susceptibility to galvanic corrosion. There were no significant differences among specimens in terms of the CR or released ions except the release of Ni ions, which was higher in Shinye brackets.

Inadvertent tooth movement with fixed lingual retainers.

Fixed retainers are effective in maintaining the alignment of the anterior teeth more than 90% of the time, but they can produce inadvertent tooth movement that in the most severe instances requires orthodontic retreatment managed with a periodontist. This is different from relapse into crowding when a fixed retainer is lost. These problems arise when the retainer breaks but remains bonded to some or all teeth, or when an intact retainer is distorted by function or was not passive when bonded. In both instances, torque of the affected teeth is the predominant outcome. A fixed retainer made with dead soft wire is the least likely to create torque problems but is the most likely to break. Highly flexible twist wires bonded to all the teeth appear to be the most likely to produce inadvertent tooth movement, but this also can occur with stiffer wires bonded only to the canines. Orthodontists, general dentists, and patients should be aware of possible problems with fixed retainers, especially those with all teeth bonded, because the patient might not notice partial debonding. Regular observations of patients wearing fixed retainers by orthodontists in the short term and family dentists in the long term are needed.

Comparative assessment of chewing gum and ibuprofen in the management of orthodontic pain with fixed appliances: A pragmatic multicenter randomized controlled trial.

INTRODUCTION: The aim of this randomized trial was to investigate the effect of the use of a sugar-free chewing gum vs ibuprofen on reported pain in orthodontic patients. METHODS: This was a 2-arm parallel design randomized controlled trial in 9 sites in the southwest of England. Patients about to undergo orthodontic treatment with maxillary and mandibular fixed appliances were recruited and randomly allocated to an experimental chewing gum group or a control ibuprofen group. Eligibility criteria included patients undergoing fixed maxillary and mandibular appliance therapy, aged 11 to 17 years, and able to use ibuprofen and chewing gum. The primary outcome measure was pain experienced after appliance placement using a mean of 3 recordings on a scale of 0 to 10. Secondary outcome measures were pain experienced in the subsequent 3 days, pain after the first archwire change, ibuprofen use, and appliance breakages. Pain scores were recorded with a questionnaire and posted to a collection center by each patient. Randomization was by means of a central telephone service and comprised computer-generated random numbers used to generate a sequential allocation list, with permuted blocks of variable size (2 and 4) and stratified by center. Neither the clinicians nor the patients were blinded to the intervention. Patients in the control group were permitted to use ibuprofen only, and patients in the experimental group were allowed to use ibuprofen if they did not get sufficient analgesia from the chewing gum. Data were analyzed using the principle of intention to treat with multilevel modeling to reflect the structured nature of the data (scores within patient within site). RESULTS: One thousand patients were recruited and randomized in a ratio of 1:1 to the chewing gum and ibuprofen (control) groups. The male-to-female ratios were similar in the groups. The pain questionnaire response rates were good at approximately 84% and 83% after appliance placement (chewing gum group, 419; ibuprofen group, 407) and 70% and 71% after the first archwire change (chewing gum group, 343; ibuprofen group, 341). The primary outcomes were similar for the 2 groups: mean pain scores, 4.31 in the chewing gum group and 4.17 in the ibuprofen group; difference, 0.14 (95% CI, -0.13 to 0.41). There was a suggestion that the relative pain scores for the 2 groups changed over time, with the chewing gum group experiencing slightly more pain on the day of bond-up and less on the subsequent 3 days; however, the differences had no clinical importance. There were no significant differences for the period after archwire change. The reported use of ibuprofen was less in the chewing gum group than in the ibuprofen group; after appliance placement, the mean numbers of occasions that ibuprofen was used were 2.1 in the chewing gum group and 3.0 in the ibuprofen group (adjusted difference, -0.96 [95% CI, -0.75 to -1.17; P <0.001]); after archwire change, the figures were 0.8 and 1.5 occasions (difference, -0.65 [-0.44 to -0.86; P <0.001]). After appliance placement and the first archwire change, there was no clinically or statistically significant difference in appliance breakages between the chewing gum and ibuprofen groups after either bond-up (7% and 8.8%, respectively) or the first archwire change (4.2% and 5.5%, respectively). No adverse events were reported. CONCLUSIONS: The use of a sugar-free chewing gum may reduce the level of ibuprofen usage but has no clinically or statistically significant effect on bond failures. REGISTRATION: International Standard Randomised Controlled Trial Number (79884739) and National Institute of Health Research (6631) portfolios. FUNDING: This research was supported by an award by the British Orthodontic Society Foundation.

Unexpected complications associated with mandibular fixed retainers: A retrospective study.

INTRODUCTION: The purposes of this retrospective study were to describe the types of unexpected complications associated with mandibular fixed retainers and to assess their prevalences and possible etiologic causes. METHODS: A total of 3500 consecutive patients (1423 male, 2077 female) treated with fixed appliances and a mandibular fixed retainer as a part of the retention protocol were screened during the retention period (2008-2013) for unexpected complications. Thirty-eight subjects (12 male, 26 female; mean age, 20.7 ± 8.9 years) with unexpected complications were identified and assigned to the unexpected complications group and compared with a randomly selected control group of 105 subjects (43 men, 62 women; mean age, 29.5 ± 9.7 years) without unexpected complications. Relationships between unexpected complications and cephalometric and clinical variables were evaluated. RESULTS: An opposite inclination of the contralateral canines (twist effect) was found in 21 subjects. In 89.5%, the left canines were tipped buccally. A torque difference of 2 adjacent incisors (X effect) was identified in 12 patients. In 5 subjects, nonspecific complications were noted. Subjects in the unexpected complications group were significantly younger at debonding (P = 0.03) and had higher mandibular plane angles (P <0.0001) and increased pretreatment ventral positions of the mandibular incisors (P = 0.029). No differences were found between the groups with regard to treatment duration, wire type, failure rate, treatment changes in incisor proclination, or intercanine distance. CONCLUSIONS: Unexpected complications of mandibular fixed retainers are relatively rare. Facial divergence was identified as a possible predictor. However, the etiology is most likely multifactorial. Strong asymmetry among the patients with the twist effect suggests that the mechanical properties of retention wires may play a role and should be examined in the future.

Emergencies in orthodontics. Part 1: Management of general orthodontic problems as well as common problems with fixed appliances.

Fixed appliance treatment is a popular treatment modality with a burgeoning increase in the numbers of children and adults realizing the benefits that can be gained. Appliance breakage is an unavoidable nuisance which is at best inconvenient, and at worst may result in significant pain or discomfort for the patient. General dental practitioners (GDPs) should have the practical knowledge of how to provide timely and appropriate orthodontic 'emergency treatment'. This will significantly reduce the sometimes considerable inconvenience and discomfort for both the patient and his/her parents, and the inevitable frustration for the clinician providing ongoing care. This first paper will deal with general orthodontic problems that commonly present, as well as some issues specific to fixed appliances. The second paper will deal with the other orthodontic appliances that may be encountered by GDPs in their daily practice. Clinical Relevance: Appropriate handling of an orthodontic 'emergency' by the general practitioner will, on many occasions, provide immediate relief of pain and distress for the patient. This will in turn allow treatment to continue moving in the right direction, thus allowing more efficient and effective use of valuable resources.

A systematic review and meta-analysis of experimental clinical evidence on initial aligning archwires and archwire sequences.

The aim of the study was to assess treatment effects and potential side effects of different archwires used on patients receiving orthodontic therapy. Electronic and manual unrestricted searches were conducted in 19 databases including MEDLINE, Cochrane Library, and Google Scholar until April 2012 to identify randomized controlled trials (RCTs) and quasi-RCTs. After duplicate study selection, data extraction, risk of bias assessment with the Cochrane risk of bias tool, and narrative analysis, mean differences (MDs) with confidence intervals (CIs) of similar studies were pooled using a random-effects model and evaluated with GRADE. A total of 16 RCTs were included assessing different archwire characteristics on 1108 patients. Regarding initial archwires, meta-analysis of two trials found slightly greater irregularity correction with an austenitic-active nickel-titanium (NiTi) compared with an martensitic-stabilized NiTi archwire (corresponding to MD: 1.11 mm, 95% CI: -0.38 to 2.61). Regarding archwire sequences, meta-analysis of two trials found it took patient treated with a sequence of martensitic-active copper-nickel-titanium (CuNiTi) slightly longer to reach the working archwire (MD: 0.54 months, 95% CI: -0.87 to 1.95) compared with a martensitic-stabilized NiTi sequence. However, patients treated with a sequence of martensitic-active CuNiTi archwires reported general greater pain intensity on the Likert scale 4 h and 1 day after placement of each archwire, compared with a martensitic-stabilized NiTi sequence. Although confidence in effect estimates ranged from moderate to high, meta-analyses could be performed only for limited comparisons, while inconsistency might pose a threat to some of them. At this point, there is insufficient data to make recommendations about the majority of initial archwires or for a specific archwire sequence.

Initial arch wires for tooth alignment during orthodontic treatment with fixed appliances.

BACKGROUND: Initial arch wires are the first arch wires to be inserted into the fixed appliance at the beginning of orthodontic treatment and are used mainly for the alignment of teeth by correcting crowding and rotations. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause the least amount of root resorption and pain during the initial aligning stage of treatment. This is an update of the review 'Initial arch wires for alignment of crooked teeth with fixed orthodontic braces' first published in the Cochrane Database of Systematic Reviews 2010, Issue 4. OBJECTIVES: To assess the effects of initial arch wires for alignment of teeth with fixed orthodontic braces in relation to alignment speed, root resorption and pain intensity. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 2 August 2012), CENTRAL (The Cochrane Library 2012, Issue 7), MEDLINE via OVID (1950 to 2 August 2012) and EMBASE via OVID (1980 to 2 August 2012). We also searched the reference lists of relevant articles. There was no restriction with regard to publication status or language of publication. We contacted all authors of included studies to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of initial arch wires to align teeth with fixed orthodontic braces. Only studies involving participants with upper and/or lower full arch fixed orthodontic appliances were included. DATA COLLECTION AND ANALYSIS: Two review authors were responsible for study selection, validity assessment and data extraction. All disagreements were resolved by discussion amongst the review team. Corresponding authors of included studies were contacted to obtain missing information. MAIN RESULTS: Nine RCTs with 571 participants were included in this review. All trials were at high risk of bias and a number of methodological limitations were identified. All trials had at least one potentially confounding factor (such as bracket type, slot size, ligation method, extraction of teeth) which is likely to have influenced the outcome and was not controlled in the trial. None of the trials reported the important adverse outcome of root resorption.Three groups of comparisons were made.(1) Multistrand stainless steel initial arch wires compared to superelastic nickel titanium (NiTi) initial arch wires. There were four trials in this group, with different comparisons and outcomes reported at different times. No meta-analysis was possible. There is insufficient evidence from these trials to determine whether or not there is a difference in either rate of alignment or pain between stainless steel and NiTi initial arch wires.(2) Conventional (stabilised) NiTi initial arch wires compared to superelastic NiTi initial arch wires. There were two trials in this group, one reporting the outcome of alignment over 6 months and the other reporting pain over 1 week. There is insufficient evidence from these trials to determine whether or not there is any difference between conventional (stabilised) and superelastic NiTi initial arch wires with regard to either alignment or pain.(3) Single-strand superelastic NiTi initial arch wires compared to other NiTi (coaxial, copper NiTi (CuNiTi) or thermoelastic) initial arch wires. The three trials in this comparison each compared a different product against single-strand superelastic NiTi. There is very weak unreliable evidence, based on one very small study (n = 24) at high risk of bias, that coaxial superelastic NiTi may produce greater tooth movement over 12 weeks, but no information on associated pain or root resorption. This result should be interpreted with caution until further research evidence is available. There is insufficient evidence to determine whether or not there is a difference between either thermoelastic or CuNiTi and superelastic NiTi initial arch wires. AUTHORS' CONCLUSIONS: There is no reliable evidence from the trials included in this review that any specific initial arch wire material is better or worse than another with regard to speed of alignment or pain. There is no evidence at all about the effect of initial arch wire materials on the important adverse effect of root resorption. Further well-designed and conducted, adequately-powered, RCTs are required to determine whether the performance of initial arch wire materials as demonstrated in the laboratory, makes a clinically important difference to the alignment of teeth in the initial stage of orthodontic treatment in patients.

A randomized clinical trial investigating pain associated with superelastic nickel-titanium and multistranded stainless steel archwires during the initial leveling and aligning phase of orthodontic treatment.

OBJECTIVE: To investigate and compare the effects of superelastic nickel-titanium and multistranded stainless steel archwires on pain during the initial phase of orthodontic treatment. DESIGN: A double-blind two-arm parallel design stratified randomized clinical trial. SETTING: A single centre in India between December 2010 and June 2012. A total of 96 participants (48 male and 48 females; 14.1±2.1 years old) were randomized (stratified on age, sex and initial crowding) to superelastic nickel-titanium or multistranded stainless steel archwire groups using a computer-generated allocation sequence. METHODS: We compared 0.016-inch superelastic nickel-titanium and 0.0175-inch multistranded stainless steel wires in 0.022-inch slot (Roth prescription) preadjusted edgewise appliances. The follow-up period was 14 days. Outcome was assessed with a visual analogue scale at baseline and 32 pre-specified follow-up points. Data was analyzed using mixed-effects model analysis. RESULTS: One participant was lost to follow up and 10 were excluded from the analysis due to bond failure or incomplete questionnaire answers. Ultimately, 85 participants (42 males and 43 females; 14.1±2.0 years old) were analysed for the final results. No statistically significant difference was found for overall pain [F value = 2.65, degrees of freedom (df) = 92.6; P = 0.1071]. However, compared to multistranded stainless steel wires, pain in subjects with superelastic nickel-titanium archwires was significantly greater at 12 h (t = 2.34; P = 0.0193), as well as at day 1 in the morning (t = 2.21, P = 0.0273), afternoon (t = 2.11, P = 0.0346) and at bedtime (t = 2.03, P = 0.042). CONCLUSION: For overall pain, there was no statistically significant difference between the two wires. However, subjects with superelastic nickel-titanium archwires had a significantly higher pain at peak level.

Incident management guidelines for an ingested orthodontic object.

Dental materials or components of orthodontics devices can fall into a patient's oropharynx, and be swallowed or inhaled. In this paper a short review of accidental foreign body ingestion/aspiration prevention, evaluation, and relevant incident management guidelines are presented. In addition, a case of an accidentally swallowed piece of archwire during a chair side procedure is reported.

The effect of chewing gum on the impact, pain and breakages associated with fixed orthodontic appliances: a randomized clinical trial.

OBJECTIVES: To determine whether the use of chewing gum reduced the impact and pain of fixed orthodontic appliances. SETTING AND SAMPLE POPULATION: The Orthodontic Department of the Charles Clifford Dental Hospital, Sheffield, UK. Fifty-seven patients aged 18 years or younger and who were about to start fixed orthodontic appliance treatment. SUBJECTS AND METHODS: A randomized clinical trial with two parallel groups either allocated to receive chewing gum after placement of their appliance or who were asked not to chew gum. The patients completed a previously validated Impact of Fixed Appliances questionnaire at 24 h and 1 week following each visit up until the placement of the working archwire. A visual analogue scale (VAS) was used to assess the intensity of pain. Appliance breakages were recorded to the end of treatment. RESULTS: The difference between the median Total Impact Score of the two groups at 24 h was 16, which was significant (p = 0.031; Mann-Whitney U-test). The difference between the median VAS between the two groups at 24 h was 25 mm, which was significant (p = 0.038; Mann-Whitney U-test). There were no differences at 1 week. None of the risk ratios for appliance breakages were significant. CONCLUSION: Chewing gum significantly decreased both the impact and pain from the fixed appliances. There was no evidence that chewing gum increased the incidence of appliance breakages.

No difference in surgical outcomes between open and closed exposure of palatally displaced maxillary canines.

PURPOSE: To investigate differences in surgical outcomes between open and closed exposure for palatally displaced maxillary canines. MATERIALS AND METHODS: This multicenter randomized controlled trial involved 2 parallel groups. The settings were 1 dental teaching hospital in and 2 hospital units near Sheffield, UK. Participants were younger than 20 years, had a unilateral palatally displaced maxillary canine, and provided informed consent. They were randomly allocated to receive the open or the closed surgical procedure. The outcomes were time spent in the operating room and 10-day postoperative patient questionnaire findings. Statistical differences between the 2 techniques were tested using independent t tests for continuous variables and χ(2) tests for frequencies. RESULTS: The final study sample was composed of 71 participants (64% female). There were no differences in the gender ratios (open: 27 female, 13 male; closed; 25 female, 16 male) or mean ages (open: 14.3 yrs; standard deviation [SD], 1.3 yrs; closed: 14.1 yrs; SD, 1.6 yrs) of the 2 groups at the start. The mean operating times for the open and closed techniques were 34.3 minutes (SD, 11.2 min) and 34.3 minutes (SD, 11.9 min), respectively (P = .986). There were no statistically significant differences between the 2 treatment groups for any patient-assessed outcome (P > .05). CONCLUSIONS: There were no differences in the surgical outcomes investigated in this study between open and closed exposure for palatally displaced maxillary canines.

Laryngeal impaction of an archwire segment after accidental ingestion during orthodontic adjustment.

Orthodontic archwires or fractured appliances that are accidentally swallowed can become lodged in the airway or gastrointestinal tract. Inadvertent ingestion or aspiration of an appliance or archwire piece during orthodontic appliance adjustment is a medical emergency with potentially serious complications, including possible death from asphyxiation. This article reports the accidental ingestion of a piece of orthodontic archwire that became impacted in the larynx; it was subsequently retrieved. Some potential complications are discussed, along with suggested precautions to prevent such mishaps when using fixed appliances.