The quality of information on the Internet on orthodontic retainer wear: a cross-sectional study

Objectives: The objectives of this study were to assess the accessibility, usability, reliability and quality of information on the Internet written for the lay public about orthodontic retainers, and to elucidate the different retention protocols encouraged. Design: A cross-sectional, observational study. Setting: Online, using a computer connected to the Internet in Australia. Methods: Two search terms; ‘orthodontic retainer’ and ‘how long should someone wear a retainer after their braces are removed?’ were entered alternatively into five search engines. Twenty results for each search term per search engine that fulfilled the inclusion criteria were evaluated in terms of accessibility, usability, reliability and quality of information using the LIDA and DISCERN instruments, ensuring there were no internal or cross-search engine duplicates. Any information about frequency and duration of retainer wear was also collected. Results: Two hundred different websites were identified and assessed. The median overall LIDA score was 72%, corresponding to a moderate quality level. The median total DISCERN score was 47%. Twenty-two websites recommended patients adhere to the specific protocol prescribed to them by their practitioner. There were 45 (22.5%) and 28 (14%) websites advising indefinite use of removable and bonded retainers respectively. Conclusions: Information about retainers on the Internet is easily accessible and usable, though the quality of the content is generally of a moderate level. However, the information is not always accurate and reliable. Both full-time and part-time wear of removable retainers was suggested over greatly varying time periods. Indefinite wear of removable and bonded retainers was also advocated.     

Cosmetic facial surgery: are online resources reliable and do patients understand them?

Our aim was to assess the quality and readability of online resources regarding common cosmetic maxillofacial procedures. We searched Google for “rhytidectomy”, “rhinoplasty”, “orthognathic surgery”, “genioplasty”, “malar implants”, “blepharoplasty”, “otoplasty”, and related terms. In each case we assessed the top 50 results for quality and readability. Quality was measured using the DISCERN questionnaire, benchmark criteria published by the Journal of the American Medical Association (JAMA), and accreditation by the HONcode (Health On the Net code). The Flesch-Kincaid reading grade, Flesch reading ease score, Gunning’s fog index, and the Coleman-Liau index, were used to measure readability. A total of 350 sites were assessed and 200 were included in the study. The mean (SD) JAMA and DISCERN scores for all included websites indicated poor quality (0.49/4 (1.07) and 32.77/80 (10.57), respectively). Only eight sites (4%) were certified by the HONcode. There was a significant association between low DISCERN scores and Google Ads (p = 0.009) and between low DISCERN scores and the websites of private clinicians or hospitals (p < 0.001). The mean (SD) Flesch reading ease score and Gunning’s fog score both indicated poor readability that required a moderately high level of literacy (50.59 (11.82) and 13.83 (2.76), respectively). The Flesch-Kincaid and Coleman-Liau scores indicated similar results. Adherence to the JAMA benchmark, certification by the HONcode, and relevant selection on Google Ads would improve quality. The avoidance of medical jargon and use of shorter sentences would improve readability and provide patients with comprehensible explanations that would allow them to have realistic expectations and take responsibility for their own health.     

Evaluation of the content quality of websites for recurrent aphthous ulcers and oral lichen planus

Background

The Internet is one of the most popular resources for people to obtain medical information; however, only a limited number of studies have reported the quality of the available health information related to oral mucosal diseases. The present study aimed to evaluate the quality of information on websites for recurrent aphthous ulcers (RAU) and oral lichen planus (OLP), in both Chinese and English.

Methods

Common search engines, BaiDu, Google, and Yahoo in Chinese; and Bing, Google, and Yahoo in English were used to identify websites providing content related to the oral mucosal diseases. The first 100 links for keywords “recurrent aphthous ulcers” and “oral lichen planus” were visited and content was downloaded within 24 h. Two separate trained researchers use the validated DISCERN rating instrument and JAMA benchmarks to evaluate the content. The rating scores were analyzed and the quality was assessed according to the scores and content of websites.

Results

A total of 145 websites for RAU and 128 of OLP were analyzed. Based on the DISCERN instrument, the quality of the content in websites for both diseases, whether in English or Chinese, was not high, generally scoring 2 to 3 (max. 5). Only 13 of the RAU websites and 21 of the OLP websites fulfilled the four criteria of the JAMA benchmarks. Generally, the scores of the English websites were higher than those of the Chinese websites. During the twelve searches, only four (Yahoo of RAU in Chinese, Bing and Yahoo of RAU in English, and Google of OLP in Chinese) showed moderate correlation between the website’s ranking and their rating scores. People cannot obtain high quality medical information if they only look at the top ranked sites on the viewing lists. Websites belonging to universities or medical centers had relatively higher scores compared with the others.

Conclusions

The quality of the content on websites relating to RAU and OLP in Chinese and English was moderate. More good quality websites and information are needed in the future.

     

Evaluation of YouTube videos about smile design using the DISCERN tool and Journal of the American Medical Association benchmarks

Statement of problemYouTube contains many videos on health-related topics. “Smile Design” is one that is frequently searched on YouTube. Whether YouTube can be considered useful for patients seeking information on smile design is unclear.PurposeThe purpose of this study was to assess and validate the features of the most popular YouTube videos on smile design.Material and methodsIn September 2019, the keyword “smile design” was searched on YouTube in North America using a virtual private network (VPN). The top 100 videos in a constantly updated list were recorded. The DISCERN instrument (Quality Criteria for Consumer Health Information) and the benchmarks established by the Journal of the American Medical Association (JAMA) were used to evaluate these 100 videos. A spreadsheet (Excel v2016; Microsoft Corp) was used to process statistical data, calculated as mean and frequency.ResultsOf the 100 videos identified, some were excluded as duplicates (11), irrelevant (4), and not presented in English (7). No video met all the JAMA criteria. Adherence to authorship and currency principles was observed in each video, and those adhering to attribution and disclosure principles were categorized as “good.” The average DISCERN score for the 78 included videos was fair (39.6 points); all videos scored poor or fair—very poor, good, or excellent scores were not found.ConclusionsThe quality of information on YouTube videos relating to smile design was only fair. Patients should use smile design information found on YouTube with caution. When professionals upload a video to YouTube, they should use evaluation tools as a quality guide.     

Orthognathic surgery: is patient information on the Internet valid?

The aims of this study were to evaluate the quality and reliability of UK websites providing information on orthognathic and jaw surgery to patients. An Internet search engine (www.google.com) was used to identify websites containing medical information on 'orthognathic surgery' and 'jaw surgery'. Of over 144,000 links for orthognathic surgery and 700,000 for jaw surgery, the first 100 were examined in detail. After excluding discussion groups, news and video feeds, and removing duplicate sites, only 25 relevant websites remained which were then evaluated using the DISCERN instrument (www.discern.org.uk/discern_instrument.php). Through the 16 questions assessing the reliability and quality of the consumer information which are scored from 1 to 5, a relative index of the quality of the information is produced. The maximum score attainable for an excellent website is 80. Of the 25 websites that were scored, DISCERN indicated the majority of websites fell well below the maximum score. The highest score achieved by one of the websites according to the DISCERN tool was 64 of 80 and the lowest score achieved was 21 of 80. The websites achieving maximum and minimum score were Wikipedia and qualitydentistry.com, respectively. By directing patients to validated websites, clinicians can ensure patients find appropriate information; however, further development of websites relating to orthognathic surgery is required. Internet information should be updated on a regular basis to account for improvements in orthodontic and surgical care.     

Self-reported oral and general health related to xerostomia,hyposalivation, and quality of life among caries active younger adults

Abstract

Objective: The aim was to study prevalence of xerostomia, hyposalivation and quality of life among caries active younger adults.

Materials and methods: A questionnaire regarding oral and general health, xerostomia and quality of life was mailed to 134 caries active (CA) and 40 caries inactive (CI) patients, 25–50 years of age (mean age 39.9?±?6.2 years) treated at a Swedish Public Dental Service clinic, regarding oral and general health, xerostomia and quality of life. Caries data and unstimulated whole salivary flow rates were obtained from dental records.

Results: The overall response rate was 69%. Dental records confirmed that CA patients had more decayed teeth over time than CI patients (p?<?.001). The CA group reported worse oral health (p?<?.001) and general health (p?<?.01), more xerostomia (p?<?.001) and lower salivary flow rate (p?<?.01) compared to CI patients. Xerostomia was inversely related to unstimulated whole salivary flow rates as well as to oral and general health (p?<?.01). There were no differences between groups in quality of life.

Conclusion: Younger caries active adult patients reported significantly more xerostomia and hyposalivation compared to caries inactive patients. Xerostomia and hyposalivation were inversely related to perceptions of oral and general health, but not to quality of life.     

Evaluation of maxillary sinus volume in different craniofacial patterns: a CBCT study

Introduction

Few studies have compared the relationship of MSV in the different craniofacial patterns. Hence, the purpose of this research was to evaluate maxillary sinus volume in different craniofacial patterns using cone-beam computed tomography.

Materials and methods

This cross-sectional study included 100 pre-orthodontic patients mean aged 26.40?±?6.77 (age ranged 21–64) years divided into different anteroposterior and vertical skeletal groups. From the cone beam computed tomography images using MIMICS 14.1 software, three-dimensional image of the maxillary sinus was constructed, and its volume was calculated.

Results

The mean maxillary sinus volume was 20,279.50?±?7800.33 mm³. Among the anteroposterior skeletal groups, the mean maxillary sinus volume in skeletal Class II group is significantly larger than class III group (P?<?0.05). Among the vertical skeletal groups, High-angle groups tend to have the largest maxillary sinus volume, though there were no significant differences among the groups (P?>?0.05). Similarly, males have significantly larger maxillary sinus volume than females (P?<?0.05). There was a positive correlation between ANB and maxillary sinus volume (P?<?0.01).

Conclusion

Maxillary sinus volume is significantly larger in skeletal class II than in skeletal class III group and in males than in females (P?<?0.05). These inferences have several implications in orthodontics, endodontics and oral surgery.

     

Available web-based teaching resources for health care professionals on screening for oral cancer

Objectives: To identify websites with adequate information on oral cancer screening for healthcare professionals (HCPs) and to assess both their quality and contents. Study Design: Websites were identified using Google and HON medical professional search engines using the terms “screening for oral cancer”. The first 100 sites retrieved by each engine were analysed using the DISCERN questionnaire (reliability), the V instrument (contents on oral cancer) and further by the Flesch-Kinkaid Reading Grade Level and the Flesch Reading Ease (readability). Results: The overall rating showed minimal shortcomings in the quality of the information in the websites. The coverage and correctness of information on “visual examination” was rated as fair/good, whereas updating of contents resulted very variable (eg: 81% for visual examination and 18.2% for molecular biomarkers). These results permitted to rank the websites housing relevant information for oral cancer. Top ranking websites were affiliated to the Oral Cancer Foundation (USA), WHO Collaborating Centre for oral cancer (UK) whose webpage is entitled “Oral Cancer Education and Research”, and the Clinical Guidelines maintained by the British Columbia Cancer Agency (Canada) and the British Dental Association (UK) respectively. Conclusions: There are web-based, HCP-addressed, resources on screening for oral cancer housing heterogeneous information both in quality and contents. The use of specific evaluation tools permits the selection of reliable websites on this topic with a potential to improve the existing educational gaps among HCPs. Key words:Oral cancer, early diagnosis, screening, secondary prevention, internet, teaching resources, continuous education.     

Skeletal-versus soft-tissue-based cephalometric analyses: is the correlation reproducible?

Objectives: Dentofacial deformities can be analyzed by skeletal and soft tissue cephalometric analysis (CA). The aim was to evaluate the difference in reproducibility between both methods.

Materials and methods: Lateral cephalograms of 112 patients (65 females and 47 males, 27.7?±?9.0 years) were oriented in natural head position (NHP) and digitized. The distances of skeletal (SNA, SNB, SnPog) and soft tissue (A′, B′ and Pog′) landmarks relative to the respective norm values and the angles between the Nasion Sella line (NSL) and Frankfurt horizontal (FH) to NHP were measured for statistical evaluation and compared with respective data of an adult control group (CG) with class I occlusion and harmonic facial balance.

Results: The mean differences (mm?±?SD) of skeletal and soft tissue landmarks were –2.4?±?4.4 (A), –7.0?±?9.3 (B), –6.3?±?11.2 (Pog), –0.9?±?1.8 (A′), –4.7?±?6.2 (B′), and –6.1?±?7.8 (Pog′), respectively. Pearsons’s correlation (r) between the measurements of SNA/A′, SNB/B′ and SNPog/Pog′ were r?=?.158 (p?=?.092), r?=?.662 (p?<?.001) and r?=?.655 (p?<?.001), respectively. The mean (±SD) angles between NSL and FH to NHP were –9.8°?±?5 and 0.0°?±?3.9, respectively.

Conclusion: Variability of cranial-based measurements could give a possible explanation for the high variation and the low reproducibility of skeletal cephalometric analysis with soft tissue measurements. Soft-tissue cephalometric analysis would probably improve facial analysis and treatment planning.     

Quality assessment of patient information on orthognathic surgery on the internet

ObjectiveThe aim of this study was to assess the quality of online information for patients on orthognathic surgery.Materials and methodsA selection of search terms specific for orthognathic surgery was chosen and 150 websites were identified using the Internet search engines Google, Yahoo and Bing. Irrelevant websites were excluded. The remaining websites were assessed with a modified Ensuring Quality Information for Patients (EQIP) tool. EQIP evaluates the quality of medical patient information by measuring the three key aspects of content, structure, and identification data.Results48 relevant websites were identified. EQIP values ranged between 2 and 28 (median 13.65). While 37 of the 48 websites described details of the surgical procedures, only 13 mentioned possible risks and complications of the surgery. No differences were found between the websites of private practices, dentists and public hospitals, universities, or others (p = 0.66). Websites found by Google had a significantly lower EQIP score compared with Yahoo and Bing (11.12 vs. 16.60 for Yahoo and 16.23 for Bing; p = 0.012). The better the rank of the website, the higher the EQIP score (r = −0.411, p = 0.004).ConclusionsThe results of this study reflected a large variation of quality of information on orthognathic surgery on the Internet. Therefore, surgeons must be aware that they might be confronted with unrealistic expectations of patients, who may underestimate the potential risks and drawbacks of orthognathic surgery.     

Sleep quality in patients with xerostomia: a prospective and randomized case-control study

Objectives To investigate sleep quality, anxiety/depression and quality-of-life in patients with xerostomia. Materials and methods This prospective, observational, cross-sectional study was conducted among a group of xerostomia patients (n?=?30) compared with 30 matched control subjects. The following evaluation scales were used to assess the psychological profile of each patient: the Hospital Anxiety and Depression Scale, the Oral Health Impact Profile-14 (OHIP-14), the Xerostomia Inventory, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Results The PSQI obtained 5.3 3?±?1.78 for patients with xerostomia compared with 4.26?±?1.01 for control subjects (p?=?0.006); ESS obtained 5.7?±?2.1 for test patients vs 4.4 0?±?1 for control subjects (p?=?0.010). Statistical regression analysis showed that xerostomia was significantly associated with depression (p?=?0.027). Conclusions Patients with xerostomia exhibited significant decreases in sleep quality compared with control subjects.     

Dose-dependent effect of radiation on resorbable blast material titanium implants: an experimental study in rabbits

Background: Radiotherapy is a commonly used treatment modality in head and neck cancer; however, it also negatively affects healthy structures. Direct damage to oral soft and hard tissue frequently occurs with radiotherapy. In this study, we aimed to evaluate the effect of radiotherapy on bone surrounding titanium dental implants via biomechanical and molecular methods.

Materials and methods: Fifty-four implants were inserted in the left tibiae of 18 adult male New Zealand rabbits (3 implants in each rabbit). After 4 weeks of the implant surgery, the left tibiae of 12 rabbits were subjected to a single dose of irradiation (15?Gy or 30?Gy). Four weeks after the irradiation, rabbits were sacrificed and removal torque test was done for the biomechanical evaluation. Bone morphogenetic protein-2 (Bmp-2) and fibroblast growth factor-2 (Fgf-2) expression analyses were performed with Real-time PCR. Statistical analysis was done using SPSS.

Results: The control group showed significantly higher removal torque value than the 15 and 30?Gy irradiation groups, and the 15?Gy irradiation group had higher removal torque value than the 30?Gy irradiation group (p?p?p?p?Conclusion: Radiotherapy with 15 and 30?Gy doses can adversely affect osseointegration of implants by reducing the quality of bone and impairing the bone-to-implant contact. The mechanism of action seems to be related to alterations in Bmp-2 and Fgf-2 mRNA expressions.     

Efficacy of statin delivery as an adjunct to scaling and root planing in the treatment of chronic periodontitis: A meta‐analysis

The action of statins in stimulating bone formation and having other pleiotropic effects, such as anti‐inflammatory and immunomodulatory effects, has justified their use as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis (CP). The aim of the present study was to evaluate the efficacy of statin delivery as an adjunct to SRP in the treatment of CP. Electronic searches were conducted using the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, up until July 2017. The primary outcome was probing depth (PD), while the secondary outcomes were changes in clinical attachment level (CAL) and bone defect (BD) fill. Eleven studies were included, and all showed significant PD reduction, CAL gain, and BD fill with adjunctive statin delivery compared to SRP alone. The meta‐analysis showed significant improvement in periodontal parameters for atorvastatin (PD: weighted mean difference [WMD] = ?1.84, ?2.56 to ?1.12, P < .001; CAL: WMD = ?2.31, ?3.58 to ?1.03, P < .001; BD fill: WMD = 2.66, ?3.92 to ?1.39, P < .001), simvastatin (PD: WMD = ?1.91, ?2.27 to ?1.55, P < .001; CAL: WMD = ?1.91, ?2.27 to ?1.55, P = .001; BD: WMD = ?1.52, ?2.20 to ?0.85, P < .001), and rosuvastatin (PD: WMD = ?0.94, ?1.32 to ?0.55, P < .001; CAL: WMD = ?1.00, ?1.41 to ?0.60, P < .001; BD fill: WMD = ?1.30, ?1.80 to ?0.79, P < .001). Adjunctive statin delivery appears to be effective in reducing PD, CAL gain, and BD fill in CP, and therefore, these drugs could be a promising therapeutic option for periodontal regeneration in future.     

Quality evaluation of the available Internet information regarding pain during orthodontic treatment

Objective:To investigate the quality of the data disseminated via the Internet regarding pain experienced by orthodontic patients.Materials and Methods:A systematic online search was performed for ‘orthodontic pain’ and ‘braces pain’ separately using five search engines. The first 25 results from each search term–engine combination were pooled for analysis. After excluding advertising sites, discussion groups, video feeds, and links to scientific articles, 25 Web pages were evaluated in terms of accuracy, readability, accessibility, usability, and reliability using recommended research methodology; reference textbook material, the Flesch Reading Ease Score; and the LIDA instrument. Author and information details were also recorded.Results:Overall, the results indicated a variable quality of the available informational material. Although the readability of the Web sites was generally acceptable, the individual LIDA categories were rated of medium or low quality, with average scores ranging from 16.9% to 86.2%. The orthodontic relevance of the Web sites was not accompanied by the highest assessment results, and vice versa.Conclusions:The quality of the orthodontic pain information cited by Web sources appears to be highly variable. Further structural development of health information technology along with public referral to reliable sources by specialists are recommended.     

Anchorage effectiveness of orthodontic miniscrews compared to headgear and transpalatal arches: a systematic review and meta-analysis

Background: Anchorage in orthodontics can be provided through several extra- and intra-oral sources including headgear, teeth, cortical bone and soft tissue.

Objective: The aim of this review was to systematically review the effectiveness of miniscrews in reinforcing anchorage during en-masse retraction of anterior teeth in comparison to conventional anchorage appliances.

Search method: Comprehensive searching of the electronic databases was undertaken up to March 2018 in the Cochrane Database of Systematic review, Cochrane Central Register of Controlled Trials, MEDLINE via PubMed and Scopus databases. Additional searching for on-going and unpublished data and hand search of relevant journals were also undertaken, authors were contacted, and reference lists screened.

Eligibility criteria: Searches were restricted to randomized clinical trials (RCTs) published in English, which compared anchorage reinforcement using mechanically-retained miniscrews (diameter of 2?mm or less) to conventional anchorage appliances during en-masse retraction of anterior teeth in participants of any age treated with fixed appliances combined with extraction of maxillary premolars.

Data collection and analysis: Blind and induplicate study selection, data extraction and risk of bias assessment were undertaken. The primary outcome was the amount of mesial movement of the upper first permanent molar (anchorage loss) while secondary outcomes included treatment duration, number of visits, adverse effects and patient-centered outcomes. The risk of bias was assessed using Cochrane risk of bias tool. A random-effects model with its corresponding 95% confidence interval (CI) were generated for comparable outcomes. Statistical heterogeneity across the studies were assessed using the I² and Chi² test. Additional sensitivity tests were implemented.

Results: Seven RCTs met the inclusion criteria, however, data of 241 participants from 6 RCTs (250 miniscrews and 134 conventional anchorage appliances) were meta-analyzed. Qualities of the included RCTs varied from low to high. The standardized mean difference (SMD) of the anchrage loss between the two intervention groups was 2.07?mm ((95% CI (–3.05) to (–1.08), p?<?.001, I²?=?88%, 6 RCTs)) in favour of miniscrews, which was also preserved after excluding the high risk of bias studies (SMD 1.94?mm, 95% CI (–2.46) to (–0.42) p?<?.001, I²?=?93%, 3 RCTs)). Information on overall treatment duration, space closure duration, quality of treatment, patient-reported outcomes, adverse effects and number of visit were limited.

Conclusion: The result of the meta-analysis suggested that there is moderate quality of evidence that miniscrews are clinically and statistically more effective in preserving orthodontic anchorage than conventional appliances. However, this conclusion is supported by a small number of studies with variable qualities. High-quality RCTs would give a better understanding of miniscrews effectiveness in providing orthodontic anchorage.     

Dental pain and oral health-related quality of life in individuals with severe dental anxiety

Objectives: To analyze the prevalence and level of dental pain among adult individuals with severe dental anxiety (DA), and the association between dental pain and oral health-related quality of life (OHRQoL).

Methods: The study was based on 170 adult individuals with DA referred to a specialized DA clinic. All patients answered a questionnaire including questions on DA (DAS, DFS), OHRQoL (OIDP) and dental pain. An adapted clinical examination and a panoramic radiograph revealed the present oral status.

Results: The prevalence of dental pain was high (77.6%) and among those reporting pain the intensity was high (49.0–61.0 on a VAS). One or more problems during the last 6 months with the mouth or teeth affecting the individual’s daily activities were reported in 85.3% of the participants. Individuals who reported dental pain had lower OHRQoL compared with those who did not report dental pain (p?p?p?=?.008).

Conclusion: This study revealed a high prevalence and a high level of dental pain among adult individuals with severe DA. Having dental pain was associated with poor OHRQoL.     

Quality of orthodontic treatment performed by orthodontists and general dentists: A blind comparative evaluation

Objective:To perform a blind comparative evaluation of the quality of orthodontic treatment provided by orthodontists and general dentists.Materials and Methods:Sixty cases of orthodontic treatment were evaluated—30 treated by specialists in orthodontics and 30 treated by general dentists with no specialization course. Orthodontists were selected randomly by lots, in a population of 1596 professionals, and recordings were performed based on the guideline established by the Objective Grading System proposed by the American Board of Orthodontics. Each participant was asked to present a case considered representative of the best outcome among the cases treated, regardless of the type or initial severity of the malocclusion. Statistical analysis involved the chi-square, Wilcoxon, and Mann-Whitney tests. The level of significance was set at P  =  .05 for the statistical tests.Results:The results showed that 29 orthodontists (96.7%) presented cases considered satisfactory and would be approved on the qualification exam, whereas only 15 dentists (50%) had cases considered satisfactory. Moreover, treatment time was significantly shorter among the orthodontists (P  =  .022), and the posttreatment comparison revealed that orthodontists achieved better outcomes considering all the variables studied.Conclusions:Orthodontists spend less time on treatment and achieve better quality outcomes than cases treated by general dentists who have not undergone a specialization course in orthodontics.     

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics

Objective: Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed retainers in orthodontics. Materials and Methods: Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain, braided, coaxial, or chain) and dimensions were selected for this study. Results: For a torquing angle of 16.2° in the 3-teeth setup torsion moments can vary between 390?cNmm and 3299?cNmm depending on the retainer wire. For the 2-teeth setup the torsion moments are much smaller. Exposure to the flame of a butane-gas torch for 10 seconds to anneal the wire reduces the stiffness of the retainer wire. Conclusions: Clinicians must select wires for fixed retainers very carefully since the difference in resistance to torque is large. A high level of torque control can be achieved with a plain 0.016?×?0.016-inch or a braided 0.016?×?0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non-uniform and non-reproducible effect.