Stability of maxillary anterior teeth during retention and 1 year after removal of retention-an RCT on adolescents retained with two different bonded retainers and a vacuum-formed retainer.

BACKGROUND: Maxillary bonded and removable retainers maintain teeth in correct positions following orthodontic treatment. There is insufficient evidence regarding the capacity of the retention methods to stabilize the maxillary teeth both during and after retention. OBJECTIVE: To evaluate retention capacity and 1-year post-retention changes in the irregularity of maxillary anterior teeth and single anterior tooth contact point discrepancy (CPD) of two bonded and one removable retention method. TRIAL DESIGN: Three-arm parallel group single-centre randomized controlled trial. METHODS: Ninety adolescent patients treated with fixed orthodontic appliances were enrolled. After gaining informed consent, the patients were randomized in blocks of 30 by an independent person into one of three groups: A) bonded retainer 13-23; B) bonded retainer 12-22; and C) removable vacuum-formed retainer. The primary outcomes were changes in Little's irregularity index (LII) and single CPD measured on digitalized casts before retention (T1), after 2 years of retention (T2), and 1-year post-retention (T3). BLINDING: The digital casts were blinded for the outcome assessor. RESULTS: Data on all 90 patients were analysed according to intention-to-treat principles. Changes in LII during retention were 0.3 mm in group A, 0.6 mm in group B, and 1.0 mm in group C. No significant differences between the groups were seen (P > 0.05). Changes during post-retention were 1.1 mm in group A, 0.5 mm in group B, and 0.4 mm in group C. Group A showed more significant changes than groups B and C (P = 0.003). During the whole post-treatment period, no significant differences were shown between the groups (P > 0.05). CPD did not differ significantly between the groups at any point. HARMS: Three patients showed changes of LII over 3 mm or CPD over 2 mm during the post-retention period, and two accepted to be realigned. LIMITATIONS: The trial was a single-centre study evaluating 1-year post-retention changes. CONCLUSIONS: The changes were clinically insignificant during and after the retention period. Thus, all three methods showed equal retention capacity. TRIAL REGISTRATION: www.clinicaltrials.com (NCT04616755).

Efficacy of the Cervical Vertebral Maturation Method: A Systematic Review.

OBJECTIVE: The present systematic review was carried out to evaluate both qualitatively and quantitatively the effectiveness of the cervical vertebral maturation (CVM) method in predicting the pubertal growth spurt. METHODS: PubMed, PMC, Scopus, SciELO, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched. The research included every article published from 1970 to June 2019, featuring the keywords: ("cervical vertebrae" OR ("cervical" AND "vertebrae") AND ("orthodontics" OR "growth and development" OR ("growth" AND "development") OR ("growth"). The Preferred Reporting Items for Reporting Systematic Reviews and Meta Analyses (PRISMA) protocol was adopted, and quality assessments modified from the "Strengthening the Reporting of Observational Studies in Epidemiology" (STROBE) and the "Standards for the Reporting of Diagnostic Accuracy Studies" (STARD) were performed to conduct this systematic review. RESULTS: Initially, 1284 articles were found. All the articles were then examined, and 43 studies met the inclusion criteria. Sixteen articles had low-quality scores, 25 had moderate scores, and 2 had high scores. The results showed a moderate to high statistically significant correlation between the CVM and other maturation methods. CONCLUSION: Overall, the CVM method can be considered an effective method and may be used with other skeletal indices for the radiographic assessment of skeletal maturity, and also to identify the growth peak in growing patients.

Cost analysis of two types of fixed maxillary retainers and a removable vacuum-formed maxillary retainer: a randomized controlled trial.

BACKGROUND: There has been an increased interest in conducting healthcare economic evaluations. Also, orthodontic treatments have gathered focus from an economic point of view, however orthodontic research seldom examines both clinical and economic outcomes. OBJECTIVE: To evaluate and compare the costs of three retention methods: a bonded retainer to the maxillary four incisors, a bonded retainer to the maxillary four incisors and canines, and a removable vacuum-formed retainer (VFR) in the maxilla. The null hypothesis was that there was no difference in costs for the three types of retention methods. TRIAL DESIGN: Three-arm, parallel group, single-centre, randomized controlled trial. MATERIALS AND METHODS: Ninety adolescent patients, 54 girls and 36 boys, treated with fixed or removable retainers in the maxilla, were recruited to the study. The patients were randomized in blocks of 30, by an independent person, to one of three groups: bonded multistranded PentaOne (Masel Orthodontics) retainer 13-23, bonded multistranded PentaOne (Masel Orthodontics) retainer 12-22, and removable VFR. A cost analysis was made regarding chair time costs based on the costs per hour for the specialist in orthodontics, and material costs plus any eventual costs for repairs of the appliance. Changes in Little's irregularity index and in single contact point discrepancies (CPDs) were measured on digitalized three-dimensional study casts. Data were evaluated on an intention-to-treat basis. The analysis was performed at 2 years of retention. RESULTS: No statistically significant difference in costs between the maxillary fixed retainers and the VFRs was found, however, the material and emergency costs were significantly higher for the VFR compared with the bonded retainers. All three retention methods showed equally effective retention capacity, and no statistically significant differences in irregularity or CPDs of the maxillary anterior teeth in the three groups was detected. LIMITATIONS: It was a single-centre trial, and hence less generalizable. Costs depended on local factors, and consequently, cannot be directly transferred to other settings. CONCLUSIONS: All three retention methods can be recommended when considering costs and retention capacity. TRIAL REGISTRATION: NCT04616755.

Comparisons of costs and treatment effects-an RCT on headgear activator treatment of excessive overjet in the mixed and late mixed dentition.

OBJECTIVES: To compare the costs and treatment effects of headgear activator treatment of Class II malocclusion with excessive overjet between treatments started in the mixed (MD) and late mixed dentition (LMD). TRIAL DESIGN: Two-arm parallel-group single-centre randomized controlled trial (RCT). MATERIAL AND METHODS: A total of 56 children presenting Class II malocclusion with excessive overjet were assessed and invited to an RCT designed as intention-to-treat. The children were randomized, by an independent person not involved in the trial into two groups, treatment with headgear activator in the MD starting at the age of 9 or to treatment with a headgear activator in LMD, starting at the age of 11. The primary outcome measure was to compare the treatment costs between the two groups. Societal costs (the sum of direct and indirect costs) were calculated for successful treatments only and when unsuccessful treatments were included. Secondary outcomes were comparisons of oral health-related quality of life (OHRQoL), dental and skeletal treatment effects, lip closure, and trauma incidence. Data collections were performed before and after treatment, corresponding to a treatment period of 2 years. Blinding was accomplished when assessing outcomes. RESULTS: No group differences in costs were found of successful treatments or when unsuccessful treatments were included. The most pronounced treatment effects in both groups were the reduction of overjet and improved molar relation. Treatment started in MD or in LMD were equal and without significant differences regarding effects on OHRQoL, skeletal effects, lip closure, and incidence of trauma. HARMS: No harm was observed, but 8 of 30 children (27%) in the MD and 6 of 21 children (29%) in the LMD group showed unsuccessful results. LIMITATIONS: Costs depend on local factors and can thereby not be directly transferred to other settings. It was a single-centre trial and can thus be less generalizable. CONCLUSIONS: Regarding costs and treatment effects, there is no difference if headgear activator treatment of excessive overjet starts in the MD or LMD. CLINICAL TRIAL REGISTRATION: NCT04508322.

Clear aligner orthodontic treatment: Angle Society of Europe consensus viewpoint.

Orthodontics has witnessed not only an exponential rise in demand from adult patients but accompanying this, the emergence of alternate aesthetic treatment options to the more traditional fixed labial appliance. The concept of using clear aligners as a means of achieving tooth movement has increased in popularity among both patients and clinicians alike. However, the question over best research evidence as to their clinical effectiveness to treat a range of malocclusion traits remains elusive and controversial among the profession.In an attempt to offer the profession some clear guidance, The Angle Society of Europe reviewed and discussed the current published evidence (2005-2018) on their clinical use, during the annual meeting in January 2020, to help formulate a consensus viewpoint on the clinical applications.

Orthodontic appliances and MR image artefacts: An exploratory in vitro and in vivo study using 1.5-T and 3-T scanners.

PURPOSE: The aim of this study was to assess the artefacts of 12 fixed orthodontic appliances in magnetic resonance images obtained using 1.5-T and 3-T scanners, and to evaluate different imaging sequences designed to suppress metal artefacts. MATERIALS AND METHODS: In vitro, study casts of 1 adult with normal occlusion were used. Twelve orthodontic appliances were attached to the study casts and scanned. Turbo spin echo (TSE), TSE with high readout bandwidth, and TSE with view angle tilting and slice encoding for metal artefact correction were used to suppress metal artefacts. Artefacts were measured. In vivo, 6 appliances were scanned: 1) conventional stainless-steel brackets; 2) nickel-free brackets; 3) titanium brackets; 4) a Herbst appliance; 5) a fixed retainer; and 6) a rapid maxillary expander. The maxilla, mandible, nasopharynx, tongue, temporomandibular joints, and cranial base/eye globes were assessed. Scores of 0, 1, 2, and 3 indicated no artefacts and minor, moderate, and major artefacts, respectively. RESULTS: In vitro, titanium brackets and the fixed retainer created minor artefacts. In vivo, titanium brackets caused minor artefacts. Conventional stainless-steel and nickel free brackets, the fixed retainer, and the rapid maxillary expander caused major artefacts in the maxilla and mandible. Conventional stainless-steel and nickel-free brackets caused major artefacts in the eye globe (3-T). TSE with high readout bandwidth reduced image artefacts in both scanners. CONCLUSION: Titanium brackets, the Herbst appliance, and the fixed retainer caused minor artefacts in images of neurocranial structures (1.5-T and 3-T) when using TSE with high readout bandwidth.

Comparison of post-treatment changes with and without retention in adolescents treated for maxillary impacted canines-a randomized controlled trial.

OBJECTIVE: To evaluate whether retention is needed after orthodontic treatment of impacted maxillary canines. TRIAL DESIGN: Two-arm parallel group single-centre randomized controlled trial. MATERIALS AND METHODS: Sixty-three patients, 39 girls and 24 boys, were recruited to the study. The inclusion criteria were patients with at least one impacted or unerupted maxillary canine, and moderate irregularity of the maxillary six anterior teeth according to Little's index (LI). After gaining informed consent from the patient and their custodians, the patients were randomized to one of two groups, i.e. to a non-retention group or a retention group. The randomization process was prepared and carried out by an independent person not involved in the trial and the randomization used blocks of 20 (10 + 10). Primary outcomes were changes in single contact point discrepancy, and LI measured on digitalized three-dimensional study casts 1-year post-treatment. The study casts were anonymized before assessment and the changes were blinded for the assessor. Data were evaluated on an intention-to-treat basis. Thus, all randomized patients were incorporated into the final analysis. In the non-retention group a 10-week interim period was used to detect patients who eventually have a relapse immediately after treatment. If so, the patient got the arch-wire reinserted. Most patients in the retention group received a vacuum-formed retainer and pretreatment spacing cases got a bonded retainer. RESULTS: Mean irregularity change was 0.4 mm in the retention and 1.3 mm in the non-retention group (P < 0.001). Maximum change was 2.5 mm in the retention and 3.2 mm in the non-retention group (P < 0.001). Most changes in the non-retention group occurred during the 10-week interim period. In the non-retention group, one patient developed contact point discrepancy of >2 mm during the interim period and was realigned. HARMS: One patient met the stopping guideline criteria. This patient had the arch wire reinserted for 2 months. After realignment, the patient received a retention appliance. LIMITATIONS: The trial was a single-centre study and short-term changes were evaluated. CONCLUSIONS: Changes between the retention and the non-retention group were statistically but not clinically significant. Since satisfactory clinical results 1-year post-treatment were found in the non-retention group, retention does not appear to be needed. The 10-week interim period was useful in detecting patients who might have a relapse immediately after treatment. TRIAL REGISTRATION: The trial was not registered.

The impact of oro-facial appearance on oral health-related quality of life: A systematic review.

Esthetics in the oro-facial region are important for perceived oral health and a common reason for treatment of discoloured, missing or crowded teeth. As one of the fundamental bricks of a patient's oral health, changes in the domain of oro-facial esthetics resides within the oral health-related quality of life (OHRQoL) of an individual. Four main dimensions, oral function, oro-facial pain, oro-facial appearance and psychosocial impact, are suggested to cover the concept of OHRQoL. The aim of this systematic review was to map the impact from oral conditions with principal impact on the oro-facial appearance dimension of OHRQoL (PROSPERO: CRD42017064033). Publications were included if they reported Oral Health Impact Profile (OHIP) mean or median domain scores for patients with esthetic treatment need relating to tooth wear, orthodontics, orthognathic surgery, frontal tooth loss or tooth whitening. A search in PubMed (Medline), EMBASE, Cochrane, CINAHL and PsycINFO 8 June 2017 and updated 14 January 2019, identified 2,104 abstracts. After screening of abstracts, 1607 articles were reviewed in full text and 33 articles included. These 33 articles reported OHIP-data for 9409 patients grouped in 63 patient populations. Median oro-facial appearance impact scores on a standardised 0-8 scale, for populations with treatment need relating to tooth wear, orthodontics, orthognathic surgery, frontal tooth loss and tooth whitening, ranged from 0.13 for tooth wear to 3.04 for tooth whitening populations. In conclusion, a moderate impact for the oro-facial appearance dimension of OHRQoL was found in patients with different conditions with esthetically related treatment need.

Early headgear activator treatment of Class II malocclusion with excessive overjet: a randomized controlled trial.

OBJECTIVES: To compare early headgear activator treatment of Class II malocclusion with excessive overjet with untreated control subjects in terms of the primary outcomes overjet and overbite as well as the effect regarding oral-health-related quality of life (OHRQoL), lip closure, incidence of trauma, and skeletal changes. TRIAL DESIGN: Two-arm parallel group single-centre randomized controlled trial. MATERIAL AND METHODS: A total of 60 children (mean age 9.5 years) presenting a Class II malocclusion with excessive overjet were recruited. The trial was designed as intention-to-treat and the participants randomized by an independent person not involved in the trial to either early treatment with headgear activator or to an untreated control group (UG). Dental and skeletal variables as well as registrations of OHRQoL, lip closure, and incidence of trauma were recorded. For the treatment group, data were registered at baseline before treatment and when treatment was finished, corresponding to approximately 2 years. For the UG, registrations were made at baseline and at 11 years of age. Observers were blinded to treatment allocation when assessing outcomes. RESULTS: Early treatment with headgear activator significantly decreased overjet and improved molar relationship when compared with untreated controls. The effects were primarily due to dentoalveolar changes. Early treatment had no evident effect regarding OHRQoL, lip closure, or incidence of trauma. Lack of cooperation resulted in unsuccessful treatments for 27% of the patients. LIMITATIONS: The trial was a single-centre trial and can thus be less generalizable. CONCLUSIONS: The main treatment effect of early headgear activator treatment of Class II malocclusion with excessive overjet is reduction of overjet. TRIAL REGISTRATION: NCT04508322.

Stability of maxillary anterior teeth after 2 years of retention in adolescents: a randomized controlled trial comparing two bonded and a vacuum-formed retainer.

BACKGROUND: Retention of the maxillary anterior teeth is commonly recommended to maintain the teeth in their corrected positions. Both fixed and removable retention methods are used, but the certainty of evidence is low. OBJECTIVE: To evaluate post-treatment changes in irregularity of the maxillary six anterior teeth and single tooth contact point discrepancy (CPD) of three different retention methods. TRIAL DESIGN: Three-arm parallel group single-centre randomized controlled trial. MATERIALS AND METHODS: Ninety patients, 54 girls and 36 boys, were recruited to the study. The inclusion criteria were adolescent patients treated with fixed appliances at least in the maxilla. After gaining informed consent from the patient and their custodians, the patients were randomized to one of three groups: bonded retainer 13-23, bonded retainer 12-22, and removable vacuum-formed retainer (VFR) covering the maxillary teeth including the second molars. The randomization, prepared by an independent person, used blocks of 30. The primary outcomes were changes in single CPD and Little's irregularity index (LII) measured on digitalized three-dimensional study casts before and after 2-year retention. The study casts were anonymized before assessment and the changes were blinded for the assessor. Data were evaluated on an intention-to-treat basis. Thus, all randomized patients were incorporated into the final analysis. RESULTS: The LII and CPDs increased slightly in all three groups without any statistically significant differences between the groups. The VFR group showed a small intercanine width increase and some more changes of canine rotations than in the other groups. HARMS: No harm was observed in any subjects and none of the patients needed retreatment. LIMITATIONS: The trial was a single-centre study and short-term changes were evaluated. CONCLUSIONS: All three retention methods showed equally effective retention capacity and all the changes found in the three groups were small and considered clinically insignificant. Thus, the null hypothesis was confirmed. All three methods can be recommended. TRIAL REGISTRATION: NCT04616755.

Mapping Oral Disease Impact with a Common Metric (MOM)-Project summary and recommendations.

Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact-the dimensions of oral health-related quality of life-capture dental patients' oral health problems worldwide and regardless of whether the patient currently suffers from oral diseases or intends to prevent them in the future. Using scores for these dimensions, the project Mapping Oral Disease Impact with a Common Metric (MOM) aims to provide four-dimensional oral health impact information across oral diseases and settings. In this article, project authors summarize MOM's findings and provide recommendations about how to improve standardized oral health impact assessment. Project MOM's systematic reviews identified four-dimensional impact information for 189 adult and 22 pediatric patient populations that were contained in 170 publications. A typical functional, pain-related, aesthetical, and psychosocial impact (on a 0-8 impact metric based on two items with a response format 0 = never, 1 = hardly ever, 2 = occasionally, 3 = fairly often, 4 = very often) was about 2 to 3 units. Project MOM provides five recommendations to improve standardized oral health impact assessment for all oral diseases in all settings.

Three-dimensional evaluation of forced unilateral posterior crossbite correction in the mixed dentition: a randomized controlled trial.

OBJECTIVES: The objectives of this study were to assess the three-dimensional (3D) treatment changes (palatal surface area and volume) of forced unilateral posterior crossbite correction using either quad-helix or removable expansion plate appliances in the mixed dentition, and to compare the treatment changes with the three-dimensional changes occurring in age-matched untreated unilateral posterior crossbite patients as well as in subjects with normal occlusion and with no or mild orthodontic treatment need. TRIAL DESIGN: Six-arm parallel group multicentre randomized controlled trial. MATERIALS AND METHODS: One-hundred and thirty-five patients with unilateral posterior crossbite with functional shift were recruited. The patients were randomized by an independent person not involved in the trial. The randomization used blocks of 25, and the patients were randomized into the following five groups: quad-helix treatments in specialist orthodontic clinics (QHS), quad-helix treatments in general dentistry (QHG), removable expansion plate treatments in specialist orthodontic clinics (EPS), removable expansion plate treatments in general dentistry (EPG), and untreated crossbite (UC). Twenty-five patients with normal occlusion who served as normal controls were also included in the trial. Blinding of the outcome assessor and data analyst was accomplished. Data on all children were evaluated on an intention-to-treat basis, regarding 3D palatal surface area, palatal projection area, and palatal shell volume; two-dimensional linear measurements were registered at the same time. RESULTS: After treatment, the surface and projection area and shell volume increased in the four treatment groups (QHS, QHG, EPS, and EPG). QHS increased significantly more than EPG for the surface and projection area. The QHS and EPS had significantly higher mean difference for shell volume. LIMITATIONS: The trial considers a short-term evaluation. CONCLUSION: After treatment, there were no significant differences between the four treatment groups and the normal group, which implies that the surface and projection area together with the shell volume for the four treatment groups and the normal group were equivalent. TRIAL REGISTRATION: The trial was registered with https://www.researchweb.org/is/sverige, registration number: 220751.

An RCT on clinical effectiveness and cost analysis of correction of unilateral posterior crossbite with functional shift in specialist and general dentistry.

OBJECTIVES: To evaluate the costs of quad-helix (QH) and removable expansion plate (EP) treatments performed either in specialist or general dentistry for the correction of unilateral posterior crossbite with functional shift in the mixed dentition. TRIAL DESIGN: Four-arm parallel group multicentre randomized controlled trial. MATERIALS AND METHODS: One hundred and ten patients with unilateral posterior crossbite with functional shift were recruited. The patients were randomized by an independent person not involved in the trial. The randomization used blocks of 20 and into the following four groups: QH treatments in specialist orthodontic clinics (QHS), QH treatments in general dentistry (QHG), EP treatments in specialist orthodontic clinics (EPS), and EP treatments in general dentistry (EPG). Blinding was accomplished of the outcome assessor and data analyst. A cost analysis was performed with reference to intention-to-treat (ITT), regarding direct costs, indirect costs, and societal costs (the sum of direct and indirect costs) for calculations of successful treatments alone and for retreatments when required. To determine which alternative has the lower cost, a cost-minimization analysis was undertaken, based on that the outcome of the treatment alternatives were broadly equivalent, so the difference between them reduces to a comparison of costs. RESULTS: In the QHS group, 28 of 28 patients were successfully corrected compared to 23 of 27 in the QHG group. Treatment with expansion plate was less successful: 18 of 27 patients in the EPS group and 18 of 28 in the EPG group. QH treatment performed in specialist orthodontic clinics had significantly lower costs than QH or EP treatment accomplished in general dentistry as well as EP treatments in specialist orthodontic clinics. LIMITATIONS: Costs depend on local factors and should not be directly extrapolated to other locations. CONCLUSION: Treatment of unilateral posterior crossbite in the mixed dentition is recommended to be performed by a specialist orthodontist using the QH appliance. TRIAL REGISTRATION: The trial was not registered.

Validity and reliability of the Swedish versions of the short-form Child Perceptions Questionnaire 11-14 and Parental Perceptions Questionnaire.

Objective: To examine the validity and reliability of the Swedish versions of the short-form Child Perceptions Questionnaire 11-14 (CPQ11-14) and Parental Perceptions Questionnaire (P-CPQ) for measuring children's oral health-related quality of life (OHRQoL). Material and methods: The sample comprised 247 children and parents. OHRQoL was assessed by asking each child and their accompanying parent to complete the relevant questionnaire. To allow test-retest analysis, 30 children and 32 parents were asked to complete the instrument a second time within 2-4 weeks. Results: In terms of construct validity, significant correlations were observed between CPQ scale scores and the global ratings of oral health and overall well-being for both the CPQ11-14 and the P-CPQ. Regarding internal consistency, Cronbach's alphas for the total scales were 0.81 and 0.77, respectively, indicating good reliability, and internal consistency for the subscales (two or four dimensions) was acceptable. Test-retest reliability was good for the CPQ11-14 total scale (ICC 0.77) and acceptable for the P-CPQ total scale (ICC 0.63). Conclusions: The Swedish versions of the short-form CPQ11-14 and P-CPQ are both valid and reliable, and can be recommended for use among Swedish children aged 11-14 years for evaluation of OHRQoL.

Agreement between children and parents in rating oral health-related quality of life using the Swedish versions of the short-form Child Perceptions Questionnaire 11-14 and Parental Perceptions Questionnaire.

Objective: To explore the agreement between children and parents on children's oral health-related quality of life (OHRQoL) when using the Swedish short forms of CPQ11-14 and P-CPQ, and to evaluate the impact on agreement of oral health including malocclusion and background characteristics (dental fear, family situation, gender of informant). Material and methods: A total of 257 children and their accompanying parents were asked to fill in the Swedish versions of the short-form CPQ11-14 and P-CPQ separately in connection with a clinical examination. Results: The participants comprised 247 child-parent pairs: 116 (47%) boys, 131 (53%) girls, 166 (67%) mothers and 81 (33%) fathers. The agreement between the child and parental ratings of the children's OHRQoL was low, with an ICC of 0.22 (95% CI: 0.04-0.37) for the total scale. Conclusions: There was a low agreement between children's and parents' answers. For best care, it is advisable to consider perceptions of both children and parents because they can complement each other in estimating the child's OHRQoL.

Publication pattern, study design, authors and countries involved in orthodontic RCTs - a bibliometric MEDLINE survey over the past 50 years.

OBJECTIVES: The objective of this study was to investigate the number and proportions, study design, journal publications, authors and countries involved in orthodontic randomised controlled trials (RCTs) over the past 50 years. METHOD: A MEDLINE database search (Entrez PubMed, http://www.ncbi.nlm.nih.gov ) was performed in November 2018 for RCT publications from 1 January 1968 to 31 December 2017. All orthodontic publications, clinical trials (CTs) or RCTs were selected. For each year from 1968 to 2017, the total number of orthodontic publications and total number of CTs and RCTs were computed. Following this, study design, journal publications, authors and countries involved in orthodontic RCTs were noted. RESULTS: The RCTs accounted for 0.1% of all orthodontic publications in the 1970s and 1980s, and, following this, the proportion of RCTs was increased and amounted to 2.7% over the past decade (2008-2017). The majority of RCTs were of single centre design (93.4%) and in 88.3% a parallel-arm design was performed. The United States and United Kingdom endorsed 16.9% and 15.5% of the RCTs, followed by Turkey (11.1%), Brazil (7.0%), Sweden (6.6%), China (5.6%), Italy (5.4%), and Germany (4.1%). Of all RCTs, 74.2% were published in 20 orthodontic journals and 25.8% in 81 non-orthodontic journals. The American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, European Journal of Orthodontics and Journal of Orthodontics contributed to 60.2% of all the RCTs. CONCLUSION: The considerable increase in orthodontic RCTs over the past 50 years implies an increased scientific impact of orthodontic literature.

How to succeed with high quality randomised clinical trials in clinical orthodontic research.

One goal of producing relevant clinical research is to ensure that evidence-based research results are transformed into everyday clinical practice that help clinicians deliver high quality care. It also involves ensuring that the individual patient receives the most effective and least risky treatment, ultimately leading to an optimal treatment outcome both in the short and long term. Some fundamentals of evidence-based dentistry are highlighted with focus on performing orthodontic randomised controlled trials.