Orthodontic retention procedures in Switzerland.

OBJECTIVE To survey retention procedures used in orthodontic practices in Switzerland. MATERIAL AND METHODS A questionnaire previously developed by Renkema et al. (2009) was sent to 223 Swiss orthodontists. The questionnaire comprised six parts, mainly containing multiple-choice questions. Information as to background education of the individual orthodontist, retention in general, frequency of different types of removable or bonded retainers that were used, retention pro- tocol, and the type and size of the wire used for bonded retainers was assessed. RESULTS The overall response rate was 65 percent. Most orthodontists placed a bonded retainer in the upper and lower arch, except when the upper arch was expanded during treatment or when extractions were performed in the upper arch, in which case they placed a combination of fixed and removable retainers. Opinions varied with regard to how many hours the removable retainers should be worn and the duration of the retention phase. As far as bonded retainers were concerned, 87 percent of the orthodontists preferred life-long retention. Ninety-three percent of the orthodontists considered that the development of a guide- line on retention procedures would be useful. CONCLUSIONS The choice of retention procedures is mostly based on orthodontists personal preference. A further research into the long-term effectiveness of individual retention protocols is needed.

Effectiveness of non-conventional methods for accelerated orthodontic tooth movement: a systematic review and meta-analysis.

OBJECTIVES To assess the available evidence on the effectiveness of accelerated orthodontic tooth movement through surgical and non-surgical approaches in orthodontic patients. METHODS Randomized controlled trials and controlled clinical trials were identified through electronic and hand searches (last update: March 2014). Orthognathic surgery, distraction osteogenesis, and pharmacological approaches were excluded. Risk of bias was assessed using the Cochrane risk of bias tool. RESULTS Eighteen trials involving 354 participants were included for qualitative and quantitative synthesis. Eight trials reported on low-intensity laser, one on photobiomodulation, one on pulsed electromagnetic fields, seven on corticotomy, and one on interseptal bone reduction. Two studies on corticotomy and two on low-intensity laser, which had low or unclear risk of bias, were mathematically combined using the random effects model. Higher canine retraction rate was evident with corticotomy during the first month of therapy (WMD=0.73; 95% CI: 0.28, 1.19, p<0.01) and with low-intensity laser (WMD=0.42mm/month; 95% CI: 0.26, 0.57, p<0.001) in a period longer than 3 months. The quality of evidence supporting the interventions is moderate for laser therapy and low for corticotomy intervention. CONCLUSIONS There is some evidence that low laser therapy and corticotomy are effective, whereas the evidence is weak for interseptal bone reduction and very weak for photobiomodulation and pulsed electromagnetic fields. Overall, the results should be interpreted with caution given the small number, quality, and heterogeneity of the included studies. Further research is required in this field with additional attention to application protocols, adverse effects, and cost-benefit analysis. CLINICAL SIGNIFICANCE From the qualitative and quantitative synthesis of the studies, it could be concluded that there is some evidence that low laser therapy and corticotomy are associated with accelerated orthodontic tooth movement, while further investigation is required before routine application.

Objective assessment of patient compliance with removable orthodontic appliances: a cross-sectional cohort study.

OBJECTIVE To assess objectively patient compliance with removable orthodontic appliances and the effect of possible influential factors. MATERIALS AND METHODS Wearing times of 45 White patients were recorded with the aid of the TheraMon microsensor. Patient compliance was assessed relative to wear prescription and other parameters, such as age and sex. RESULTS There was high individual variation in most measured variables and in all groups/subgroups. During a median observation period of 186 days (range, 55-318 days) the actual wear time was 9.0 h/d (range, 0.0-16.0 h/d) and did not differ between distinct prescriptions (P = .49). Eight patients wore their appliances less than 2 h/d, and six of them did not wear their appliances at all. Overall, the median wear per day relative to prescription was 62.5% (range, 0.0-89.3%) for the 14 h/d and 112.5% (range, 0.0-200.0%) for the 8 h/d prescription wear (P = .01) groups. There was a strong negative correlation of age (median: 12.5 years) with the daily percentage of actual wear time per day relative to wear prescription (14 h/d prescription: n = 21, rho = -0.61, P = .00; 8 h/d prescription: n = 24, rho = -0.73, P = .00), while sex did not exert a significant influence on compliance (P = .58). CONCLUSIONS Despite the fact that patients and parents were informed about wear time recording, compliance was insufficient with regard to functional treatment (14 h/d prescription), while it was sufficient for retention purposes (8 h/d prescription). Objective measures are necessary to assess compliance with removable orthodontic appliances since patient compliance is a highly variable issue.

Success rate of paramedian palatal implants in adolescent and adult orthodontic patients: a retrospective cohort study.

The purpose of this study was to examine the success rate of paramedian palatal Orthosystem first- and second-generation implants used for anchorage in orthodontic treatment in patients treated by one experienced orthodontist. The records of 143 patients (90 female, 53 male, median age: 15.7 years, range: 10.2-50.9) receiving 145 palatal implants of the first or second generation (Orthosystem, Straumann AG, Basel, Switzerland) were examined. All the palatal implants were placed in a paramedian palatal location by three experienced surgeons. Stable implants were orthodontically loaded after a healing period of 3 months. Out of the 145 inserted paramedian palatal implants only seven implants (4.8%) were not considered stable after insertion. All the successfully osseointegrated implants remained stable during orthodontic treatment. Paramedian palatal implants are highly reliable and effective devices to obtain skeletal anchorage for orthodontic treatment. This study has shown that the paramedian location is a good alternative to the median location.

Microstructural and mechanical characterization of contemporary lingual orthodontic brackets.

OBJECTIVES To investigate the composition and the microstructural and mechanical characterization of three different types of lingual brackets. MATERIALS AND METHODS Incognito™ (3M Unitek), In-Ovation L (DENTSPLY GAC) and STb™ (Light Lingual System, ORMCO) lingual brackets were studied under the scanning electron microscope employing backscattered electron imaging and their elemental composition was analysed by energy-dispersive X-ray microanalysis. Additionally, Vickers hardness was assessed using a universal hardness-testing machine, and the indentation modulus was measured according to instrumented indentation test. Two-way analysis of variance was conducted employing bracket type and location (base and wing) as discriminating variable. Significant differences among groups were allocated by post hoc Student-Newman-Keuls multiple comparison analysis at 95% level of significance. RESULTS Three different phases were identified for Incognito and In-Ovation L bracket based on mean atomic number contrast. On the contrary, STb did not show mean atomic contrast areas and thus it is recognized as a single phase. Incognito is a one-piece bracket with the same structure in wing and base regions. Incognito consists mainly of noble metals while In-Ovation L and STb show similar formulations of ferrous alloys in wing and base regions. No significant differences were found between ferrous brackets in hardness and modulus values, but there were significant differences between wing and base regions. Incognito illustrated intermediate values with significant differences from base and wing values of ferrous brackets. CONCLUSIONS/IMPLICATIONS Significant differences exist in microstructure, elemental composition, and mechanical properties among the brackets tested; these might have a series of clinical implications during mechanotherapy.

Indication and timing of soft tissue augmentation at maxillary and mandibular incisors in orthodontic patients. A systematic review.

OBJECTIVE To assess the indication and timing of soft tissue augmentation for prevention or treatment of gingival recession when a change in the inclination of the incisors is planned during orthodontic treatment. MATERIALS AND METHODS Electronic database searches of literature were performed. The following electronic databases with no restrictions were searched: MEDLINE, EMBASE, Cochrane, and CENTRAL. Two authors performed data extraction independently using data collection forms. RESULTS No randomized controlled trial was identified. Two studies of low-to-moderate level of evidence were included: one of prospective and retrospective data collection and one retrospective study. Both implemented a periodontal intervention before orthodontics. Thus, best timing of soft tissue augmentation could not be assessed. The limited available data from these studies appear to suggest that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontics may yield satisfactory results with respect to the development or progression of gingival recessions. However, the strength of the available evidence is not adequate in order to change or suggest a possible treatment approach in the daily practice based on solid scientific evidence. CONCLUSIONS Despite the clinical experience that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontic treatment may be a clinically viable treatment option in patients considered at risk, this treatment approach is not based on solid scientific evidence. Moreover, the present data do not allow to draw conclusions on the best timing of soft tissue augmentation when a change in the inclination of the incisors is planned during orthodontic treatment and thus, there is a stringent need for randomized controlled trials to clarify these open issues.

Factorial designs: an overview with applications to orthodontic clinical trials.

Factorial designs for clinical trials are often encountered in medical, dental, and orthodontic research. Factorial designs assess two or more interventions simultaneously and the main advantage of this design is its efficiency in terms of sample size as more than one intervention may be assessed on the same participants. However, the factorial design is efficient only under the assumption of no interaction (no effect modification) between the treatments under investigation and, therefore, this should be considered at the design stage. Conversely, the factorial study design may also be used for the purpose of detecting an interaction between two interventions if the study is powered accordingly. However, a factorial design powered to detect an interaction has no advantage in terms of the required sample size compared to a multi-arm parallel trial for assessing more than one intervention. It is the purpose of this article to highlight the methodological issues that should be considered when planning, analysing, and reporting the simplest form of this design, which is the 2 × 2 factorial design. An example from the field of orthodontics using two parameters (bracket type and wire type) on maxillary incisor torque loss will be utilized in order to explain the design requirements, the advantages and disadvantages of this design, and its application in orthodontic research.

Full-text publication of abstracts presented at European Orthodontic Society congresses.

INTRODUCTION Empirical evidence has indicated that only a subsample of studies conducted reach full-text publication and this phenomenon has become known as publication bias. A form of publication bias is the selectively delayed full publication of conference abstracts. The objective of this article was to examine the publication status of oral abstracts and poster-presentation abstracts, included in the scientific program of the 82nd and 83rd European Orthodontic Society (EOS) congresses, held in 2006 and 2007, and to identify factors associated with full-length publication. METHODS A systematic search of PubMed and Google Scholar databases was performed in April 2013 using author names and keywords from the abstract title to locate abstract and full-article publications. Information regarding mode of presentation, type of affiliation, geographical origin, statistical results, and publication details were collected and analyzed using univariable and multivariable logistic regression. RESULTS Approximately 51 per cent of the EOS 2006 and 55 per cent of the EOS 2007 abstracts appeared in print more than 5 years post congress. A mean period of 1.32 years elapsed between conference and publication date. Mode of presentation (oral or poster), use of statistical analysis, and research subject area were significant predictors for publication success. LIMITATIONS Inherent discrepancies of abstract reporting, mainly related to presentation of preliminary results and incomplete description of methods, may be considered in analogous studies. CONCLUSIONS On average 52.2 per cent of the abstracts presented at the two EOS conferences reached full publication. Abstracts presented orally, including statistical analysis, were more likely to get published.

Investigation of bacteremia induced by removal of orthodontic mini-implants.

The aim of this study was to investigate potential occurrence of bacteremia in orthodontic patients after removal of miniscrews.The study group comprised 30 healthy subjects (17 males, 13 females) with a mean age of 24.1 years treated with self-ligating fixed appliances and mini-implant anchorage. Two 20 ml venous blood samples were obtained prior to and 30-60 seconds after miniscrew explantation following an aseptic technique. Blood culturing in aerobic and anaerobic conditions was carried out by means of the BACTEC blood culture analyzer. Microbiological analysis showed that none of the pre- and post-operative samples exhibited detectable bacteremia. Future research should be focused on determining the collective bacteremic effect of a sequence of orthodontic procedures including miniscrew placement or removal, typically performed during a single treatment session.

Initial orthodontic alignment effectiveness with self-ligating and conventional appliances: a network meta-analysis in practice.

Systematic reviews of well-designed trials constitute a high level of scientific evidence and are important for medical decision making. Meta-analysis facilitates integration of the evidence using a transparent and systematic approach, leading to a broader interpretation of treatment effectiveness and safety than can be attained from individual studies. Traditional meta-analyses are limited to comparing just 2 interventions concurrently and cannot combine evidence concerning multiple treatments. A relatively recent extension of the traditional meta-analytical approach is network meta-analysis, which allows, under certain assumptions, the quantitative synthesis of all evidence under a unified framework and across a network of all eligible trials. Network meta-analysis combines evidence from direct and indirect information via common comparators; interventions can therefore be ranked in terms of the analyzed outcome. In this article, the network meta-analysis approach is introduced in a nontechnical manner using a worked example on the treatment effectiveness of conventional and self-ligating appliances.

The timing of significant arch dimensional changes with fixed orthodontic appliances: data from a multicenter randomised controlled trial.

OBJECTIVES To identify the timing of significant arch dimensional increases during orthodontic alignment involving round and rectangular nickel-titanium (NiTi) wires and rectangular stainless steel (SS). A secondary aim was to compare the timing of changes occurring with conventional and self-ligating fixed appliance systems. METHODS In this non-primary publication, additional data from a multicenter randomised trial initially involving 96 patients, aged 16 years and above, were analysed. The main pre-specified outcome measures were the magnitude and timing of maxillary intercanine, interpremolar, and intermolar dimensions. Each participant underwent alignment with a standard Damon (Ormco, Orange, CA) wire sequence for a minimum of 34 weeks. Blinding of clinicians and patients was not possible; however, outcome assessors and data analysts were kept blind to the appliance type during data analysis. RESULTS Complete data were obtained from 71 subjects. Significant arch dimensional changes were observed relatively early in treatment. In particular, changes in maxillary inter-first and second premolar dimensions occurred after alignment with an 0.014in. NiTi wire (P<0.05). No statistical differences in transverse dimensions were found between rectangular NiTi and working SS wires for each transverse dimension (P>0.05). Bracket type had no significant effect on the timing of the transverse dimensional changes. CONCLUSIONS Arch dimensional changes were found to occur relatively early in treatment, irrespective of the appliance type. Nickel-titanium wires may have a more profound effect on transverse dimensions than previously believed. CLINICAL SIGNIFICANCE On the basis of this research orthodontic expansion may occur relatively early in treatment. Nickel-titanium wires may have a more profound effect on transverse dimensions than previously believed.

Exploring the publications in three major orthodontic journals: a comparative analysis of two 5-year periods.

OBJECTIVE To analyze the types of articles and authorship characteristics of three orthodontic journals--American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), The Angle Orthodontist (AO), and European Journal of Orthodontics (EJO)--published between 2008 and 2012 and to assess the differences in content within this period and an earlier period of 1998 to 2002. MATERIALS AND METHODS Each journal's content was accessed through the web edition. From each article, the following parameters were recorded: article type, number of authors, number of affiliations, source of article (referring to the first author's affiliation), and geographic origin. Descriptive statistics were performed and selected parameters were analyzed with the Pearson chi-square or Fisher exact test for independence at the .05 level of significance. RESULTS Review of differences between the two periods showed that the number of publications was almost double. The percentages of multi-authored articles increased. Fewer studies derived from the United States/Canada and European Union countries. Increases for articles from non-European Union countries, Asia, and other countries were found. Characteristics of the second period showed that the EJO and AO published more research articles, whereas the AJODO regularly published case reports and other articles. Approximately 75% of all studies derived from orthodontic departments. CONCLUSIONS The publications from 1998-2002 and 2008-2012 were significantly different both in terms of numbers and characteristics. Within 2008-2012 there were notable differences between the three journals concerning the type and origin of the publications.

Sample size in orthodontic randomized controlled trials: are numbers justified?

Sample size calculations are advocated by the Consolidated Standards of Reporting Trials (CONSORT) group to justify sample sizes in randomized controlled trials (RCTs). This study aimed to analyse the reporting of sample size calculations in trials published as RCTs in orthodontic speciality journals. The performance of sample size calculations was assessed and calculations verified where possible. Related aspects, including number of authors; parallel, split-mouth, or other design; single- or multi-centre study; region of publication; type of data analysis (intention-to-treat or per-protocol basis); and number of participants recruited and lost to follow-up, were considered. Of 139 RCTs identified, complete sample size calculations were reported in 41 studies (29.5 per cent). Parallel designs were typically adopted (n = 113; 81 per cent), with 80 per cent (n = 111) involving two arms and 16 per cent having three arms. Data analysis was conducted on an intention-to-treat (ITT) basis in a small minority of studies (n = 18; 13 per cent). According to the calculations presented, overall, a median of 46 participants were required to demonstrate sufficient power to highlight meaningful differences (typically at a power of 80 per cent). The median number of participants recruited was 60, with a median of 4 participants being lost to follow-up. Our finding indicates good agreement between projected numbers required and those verified (median discrepancy: 5.3 per cent), although only a minority of trials (29.5 per cent) could be examined. Although sample size calculations are often reported in trials published as RCTs in orthodontic speciality journals, presentation is suboptimal and in need of significant improvement.

A comparison of apical root resorption after orthodontic treatment with surgical exposure and traction of maxillary impacted canines versus that without impactions.

SUMMARY BACKGROUND/OBJECTIVES Orthodontic management of maxillary canine impaction (MCI), including forced eruption, may result in significant root resorption; however, the association between MCI and orthodontically induced root resorption (OIRR) is not yet sufficiently established. The purpose of this retrospective cohort study was to comparatively evaluate the severity of OIRR of maxillary incisors in orthodontically treated patients with MCI. Additionally, impaction characteristics were associated with OIRR severity. SUBJECTS AND METHODS The sample comprised 48 patients undergoing fixed-appliance treatment-24 with unilateral/bilateral MCI and 24 matched controls without impaction. OIRR was calculated using pre- and post-operative panoramic tomograms. The orientation of eruption path, height, sector location, and follicle/tooth ratio of the impacted canine were also recorded. Mann-Whitney U-test and univariate and multivariate linear mixed models were used to test for the associations of interest. RESULTS Maxillary central left incisor underwent more OIRR in the impaction group (mean difference = 0.58mm, P = 0.04). Overall, the impaction group had 0.38mm more OIRR compared to the control (95% confidence interval, CI: 0.03, 0.74; P = 0.04). However, multivariate analysis demonstrated no difference in the amount of OIRR between impaction and non-impaction groups overall. A positive association between OIRR and initial root length was observed (95% CI: 0.08, 0.27; P < 0.001). The severity of canine impaction was not found to be a significant predictor of OIRR. LIMITATIONS This study was a retrospective study and used panoramic tomograms for OIRR measurements. CONCLUSIONS This study indicates that MCI is a weak OIRR predictor. Interpretation of the results needs caution due to the observational nature of the present study.

Assessment of Intramedullary Spinal Pressure in Small Breed Dogs With Thoracolumbar Disk Extrusion Undergoing Hemilaminectomy

OBJECTIVE To assess intramedullary spinal pressure (IMP) in small breed dogs with thoracolumbar disk extrusion. STUDY DESIGN Prospective cohort study. ANIMALS Small breed dogs (n = 14) with thoracolumbar disk extrusion undergoing hemilaminectomy and healthy chondrodystrophic laboratory dogs (control; n = 3) without spinal disease. METHODS Diagnosis was based on clinical and neurological examinations and magnetic resonance imaging (MRI) and was confirmed intraoperatively. A standardized anesthesia protocol and surgical procedure were used to minimize factors that could influence IMP. Intramedullary pressure was measured through a minidurotomy at the site of spinal cord compression using a fiber optic catheter inserted perpendicular to the longitudinal axis of the spinal cord. Measurements were taken after hemilaminectomy and again after removal of extruded disk material. RESULTS Affected dogs had significantly higher IMP compared to control dogs (P = .008) and IMP decreased significantly post-decompression compared with initial values (P < .001). No correlation was found between IMP and neurologic grade, degree of spinal cord compression on MRI, or signal intensity changes on MRI. CONCLUSION Acute thoracolumbar disk extrusion is associated with increased IMP in small breed dogs and surgical decompression results in an immediate decrease of IMP.