Orthodontic retention: Rationale and periodontal implications.

Post-treatment change in the form of true relapse and physiological and maturational effects is common following orthodontics. The unpredictable nature of these manifestations dictates a conservative, near-universal approach to retention. Both fixed and removable forms of retention are popular with the latter constrained by variable levels of adherence particularly in the medium- to long-term. Fixed retention may offer a more predictable means of preservation of orthodontic outcomes; however, this advantage is offset by the requirement for prolonged supervision and the potential for adverse changes including periodontal breakdown. Nevertheless, while examples of severe complications are common, a clear causal relationship between intact, passive retainers and periodontal issues does not appear to exist. Nevertheless, the importance of diligent maintenance and careful supervision during fixed retention, in particular, cannot be disregarded.

Assessment of wear characteristics, longevity and stiffness of Essix-type retainers.

OBJECTIVE: To compare four commercially available Essix-type retainers in terms of longevity, wear characteristics, stiffness and their range of rigidity. MATERIALS AND METHODS: An in vitro study was conducted at Queen Mary University of London. Four groups of thermoplastic materials were included: Duran (PETG), Essix C + (Polypropylene), Vivera and Zendura (Polyurethane). A working typodont was fabricated to evaluate surface wear characteristics using a wear machine with a customized jig. Retainers were measured for tensile test, and water absorption was measured at five different time points up to 6 months after initial immersion in two different physical states and two different solutions. Hydrolytic degradation was also evaluated using FTIR spectroscopy. RESULTS: Essix C + was the most flexible retainer with Vivera the stiffest material. Zendura and Essix C + had the most surface wear (413 µm ± 80 and 652 µm ± 12, respectively) with absorption rates of up to 15 wt% in artificial saliva occurring with Zendura. Only Essix C + displayed signs of degradation following water absorption. CONCLUSIONS: All materials had characteristic levels of flexibility and were susceptible to water absorption. Duran 1.5 mm performed similarly to Vivera in relation to stiffness and wear properties. While Zendura and Vivera have similar chemical structures, they exhibited differences concerning wear resistance and water absorption. Further clinical research evaluating the clinical relevance of these laboratory findings is required. CLINICAL RELEVANCE: Characteristic patterns of wear and rigidity of four commercially available Essix-type retainers were observed. This information should help in the tailoring of retainer material on a case-by-case basis considering treatment-related factors and patient characteristics including parafunctional habits.

Midpalatal miniscrew insertion: The accuracy of digital planning and surgical placement.

INTRODUCTION: The objective of this study was to investigate the accuracy of palatal miniscrew insertion, evaluating the effect of guide fabrication and surgical placement. METHODS: Guided insertion of bilateral paramedian palatal miniscrews was undertaken using Appliance Designer software (3Shape, Copenhagen, Denmark). A resin surgical guide (P Pro Surgical Guide; Straumann AG, Basel, Switzerland) was used. Superimposition of the miniscrew position relative to the digital design was undertaken using bespoke software (Inspect 3D module, OnyxCeph; Image Instruments GmbH, Chemnitz, Germany) to assess surgical inaccuracy. Miniscrew position relative to the surgical guide was also assessed to isolate the effect of planning inaccuracies. Both horizontal and vertical discrepancies were evaluated at both implant locations. RESULTS: Twenty-seven patients having bilateral palatal insertions were examined. Mean discrepancies were <0.5 mm, both in the horizontal and vertical planes. The mean overall horizontal and vertical discrepancy between the digital design and final miniscrew position on the left side was 0.32 ± 0.15 mm and 0.34 ± 0.17 mm, respectively. The maximum horizontal discrepancy observed was 0.72 mm. No significant differences were observed in relation to the accuracy of mini-implant positioning on the basis of sidedness, either for horizontal (P = 0.29) or vertical (P = 0.86) discrepancy. CONCLUSIONS: High levels of accuracy associated with guided insertion of paramedian palatal implants were recorded with mean discrepancies of less than 0.5 mm both in the horizontal and vertical planes. No difference in accuracy was noted between the left and right sides. Very minor levels of inaccuracy associated both with surgical techniques and surgical guide fabrication were recorded.

"Over-reviewing" of research? An analysis of orthodontic reviews.

INTRODUCTION: Research overviews may be undertaken to identify gaps in the literature, evaluate existing systematic reviews (SRs), and summarize evidence. This paper aims to profile overviews that have been conducted in orthodontics and related interventions since 2012 and to evaluate the degree of overlap among these overviews. METHODS: Overviews published between January 1, 2012 and June 20, 2023 were identified using an electronic search involving Google Scholar and PubMed. A descriptive summary was produced, and citation matrices were used to evaluate the percentage of overlap between overviews using corrected covered area and covered area. This was classified as slight, moderate, high, or very high. RESULTS: A total of 35 overviews were identified across a wide range of topics. Eight overviews included <10 SRs; 21 had 10-20 SRs; and 6 included >20 SRs (median no. of SRs per overview, 15; range, 3-62). Meta-analysis was conducted in only 5 overviews. Overlap between overviews on the same topic ranged from slight (2.7%) to very high (53.8%). CONCLUSIONS: Almost all overview topics address treatments and their effects, with a wide variation in the number and quality of SRs included. There is considerable overlap in some orthodontic overviews, suggesting unnecessary duplication and research waste. Researchers should be encouraged to focus on primary data collection to add more high-quality data to SRs, which will ultimately enhance the yield from secondary and tertiary orthodontic research.

The skeletal and dental effects of Hanks Herbst versus twin block appliances for class II correction in growing patients: a randomized clinical trial.

BACKGROUND: Despite the popularity of the Twin Block (TB) and the Hanks Herbst (HH) functional appliances, there is limited prospective research comparing these removable and fixed designs, respectively. OBJECTIVES: To evaluate and compare the skeletal and dental effects associated with TB and HH functional appliances as well as to detect factors that might influence the success or failure of treatment in adolescents with Class II malocclusion. DESIGN AND SETTING: A parallel-group randomized controlled trial was undertaken in a single-centre hospital in the United Kingdom. METHODS: A total of 80 participants (aged 10-14 years) with overjet of 7 mm or more were randomized to receive either the HH or TB appliance. Cephalometric radiographs were collected at the start of the study and immediately after the withdrawal of the functional appliances and measured using Pancherz analysis. Participants were allocated to the TB or HH group, based on an electronic randomization, stratified for gender and allocation concealed. Blinding to the allocated arm was not possible. However, all data were coded and anonymized to ensure that assessors were blinded to the group allocation. The main outcome was the anterior-posterior skeletal and dento-alveolar changes at the end of the functional phase. RESULTS: Fifteen (37.5%) participants from the TB group and 7 (15.5%) from HH failed to achieve full overjet reduction (<4 mm) after 12 months of treatment. Overjet reduction was 2 mm greater with HH compared to TB (P = .05; 95% CI: 0.2, 3.2). No significant differences regarding skeletal and dental changes were reported, with the exception that participants in HH group experienced greater lower molar protraction (P = .002; 95% CI: -2.8, -0.8) and mandibular incisors advancement (P = .001; 95% CI: -2.9, -1), indicating greater dental than skeletal effects. CONCLUSION: The TB appliance was associated with a higher rate of treatment discontinuation. No significant clinical differences were observed in the skeletal and dental effects, although the HH may be associated with more pronounced effects on the mandibular dentition. CLINICAL TRIAL REGISTRATION: The protocol was registered online before the start of the trial (ISRCTN11717011).

Non-surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic treatment.

BACKGROUND: Deviation from a normal bite can be defined as malocclusion. Orthodontic treatment takes 20 months on average to correct malocclusion. Accelerating the rate of tooth movement may help to reduce the duration of orthodontic treatment and associated unwanted effects including orthodontically induced inflammatory root resorption (OIIRR), demineralisation and reduced patient motivation and compliance. Several non-surgical adjuncts have been advocated with the aim of accelerating the rate of orthodontic tooth movement (OTM).         OBJECTIVES: To assess the effect of non-surgical adjunctive interventions on the rate of orthodontic tooth movement and the overall duration of treatment. SEARCH METHODS: An information specialist searched five bibliographic databases up to 6 September 2022 and used additional search methods to identify published, unpublished and ongoing studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of people receiving orthodontic treatment using fixed or removable appliances along with non-surgical adjunctive interventions to accelerate tooth movement. We excluded split-mouth studies and studies that involved people who were treated with orthognathic surgery, or who had cleft lip or palate, or other craniofacial syndromes or deformities. DATA COLLECTION AND ANALYSIS: Two review authors were responsible for study selection, risk of bias assessment and data extraction; they carried out these tasks independently. Disagreements were resolved by discussion amongst the review team to reach consensus.  MAIN RESULTS: We included 23 studies, none of which were rated as low risk of bias overall. We categorised the included studies as testing light vibrational forces or photobiomodulation, the latter including low level laser therapy and light emitting diode. The studies assessed non-surgical interventions added to fixed or removable orthodontic appliances compared to treatment without the adjunct. A total of 1027 participants (children and adults) were recruited with loss to follow-up ranging from 0% to 27% of the original samples.  Certainty of the evidence For all comparisons and outcomes presented below, the certainty of the evidence is low to very low. Light vibrational forces  Eleven studies assessed how applying light vibrational forces (LVF) affected orthodontic tooth movement (OTM). There was no evidence of a difference between the intervention and control groups for duration of orthodontic treatment (MD -0.61 months, 95% confidence interval (CI) -2.44 to 1.22; 2 studies, 77 participants); total number of orthodontic appliance adjustment visits (MD -0.32 visits, 95% CI -1.69 to 1.05; 2 studies, 77 participants); orthodontic tooth movement during the early alignment stage (reduction of lower incisor irregularity (LII)) at 4-6 weeks (MD 0.12 mm, 95% CI -1.77 to 2.01; 3 studies, 144 participants), or 10-16 weeks (MD -0.18 mm, 95% CI -1.20 to 0.83; 4 studies, 175 participants); rate of canine distalisation (MD -0.01 mm/month, 95% CI -0.20 to 0.18; 2 studies, 40 participants); or rate of OTM during en masse space closure (MD 0.10 mm per month, 95% CI -0.08 to 0.29; 2 studies, 81 participants). No evidence of a difference was found between LVF and control groups in rate of OTM when using removable orthodontic aligners. Nor did the studies show evidence of a difference between groups for our secondary outcomes, including patient perception of pain, patient-reported need for analgesics at different stages of treatment and harms or side effects.  Photobiomodulation Ten studies assessed the effect of applying low level laser therapy (LLLT) on rate of OTM. We found that participants in the LLLT group had a statistically significantly shorter length of time for the teeth to align in the early stages of treatment (MD -50 days, 95% CI -58 to -42; 2 studies, 62 participants) and required fewer appointments (-2.3, 95% CI -2.5 to -2.0; 2 studies, 125 participants). There was no evidence of a difference between the LLLT and control groups in OTM when assessed as percentage reduction in LII in the first month of alignment (1.63%, 95% CI -2.60 to 5.86; 2 studies, 56 participants) or in the second month (percentage reduction MD 3.75%, 95% CI -1.74 to 9.24; 2 studies, 56 participants). However, LLLT resulted in an increase in OTM during the space closure stage in the maxillary arch (MD 0.18 mm/month, 95% CI 0.05 to 0.33; 1 study; 65 participants; very low level of certainty) and the mandibular arch (right side MD 0.16 mm/month, 95% CI 0.12 to 0.19; 1 study; 65 participants). In addition, LLLT resulted in an increased  rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; 1 study, 37 participants). These  findings were not clinically significant. The studies showed no evidence of a difference between groups for our secondary outcomes, including OIIRR, periodontal health and patient perception of pain at early stages of treatment. Two studies assessed the influence of applying light-emitting diode (LED) on OTM. Participants in the LED group required a significantly shorter time to align the mandibular arch compared to the control group (MD -24.50 days, 95% CI -42.45 to -6.55, 1 study, 34 participants). There is no evidence that LED application increased the rate of OTM during maxillary canine retraction (MD 0.01 mm/month, 95% CI 0 to 0.02; P = 0.28; 1 study, 39 participants ). In terms of secondary outcomes, one study assessed patient perception of pain and found no evidence of a difference between groups.   AUTHORS' CONCLUSIONS: The evidence from randomised controlled trials concerning the effectiveness of non-surgical interventions to accelerate orthodontic treatment is of low to very low certainty. It suggests that there is no additional benefit of light vibrational forces or photobiomodulation for reducing the duration of orthodontic treatment. Although there may be a limited benefit from photobiomodulation application for accelerating discrete treatment phases, these results have to be interpreted with caution due to their questionable clinical significance. Further well-designed, rigorous RCTs with longer follow-up periods spanning from start to completion of orthodontic treatment are required to determine whether non-surgical interventions may reduce the duration of orthodontic treatment by a clinically significant amount, with minimal adverse effects.

The effectiveness of adjuncts or alternatives to the use of orthodontic retainers in preserving posttreatment outcomes: A systematic review.

INTRODUCTION: The objective of this study was to systematically evaluate the efficacy of adjuncts or alternatives to mechanical retention in preserving postorthodontic treatment outcomes. METHODS: Electronic databases, unpublished literature, and ongoing trials were searched until July 22, 2022 (PROSPERO CRD42021291165). Randomized and nonrandomized controlled trials investigating the efficacy of adjuncts and alternatives to conventional orthodontic retainers were included. Stability, periodontal effects, cost-effectiveness, and patient-reported outcomes were to be evaluated. The Cochrane Risk of Bias Tool and Risk of Bias In Nonrandomized Studies of Interventions (ROBINS-I) were used for risk of bias assessment. The certainty of the evidence was appraised using the Grading of Recommendations Assessment, Development, and Evaluation system. Exploratory sensitivity analysis was undertaken to calculate the weighted treatment effects of the intervention. RESULTS: A total of 5128 records were screened. Seven trials fulfilled the inclusion criteria, of which 5 were randomized controlled trials. Five trials were judged to be at high risk of bias, with 2 studies of unclear risk of bias. Heterogeneity between the limited number of included studies precluded the conduct of meta-analysis. Circumferential supracrestal fibrotomy resulted in less increase in the mandibular Little's Irregularity Index (mean difference, -2.30 mm; 95% confidence interval, -2.86 to -1.74). The overall level of evidence was of very low quality. CONCLUSIONS: Adjuncts and alternatives to mechanical retention have promise, but based on the existing evidence, the reliance on mechanical retention cannot be reduced. There is weak evidence supporting circumferential supracrestal fibrotomy to improve stability outcomes. Further high-quality prospective research focusing on the predictability and acceptability of these approaches is needed.

The use of the Hanks Herbst vs Twin-block in Class II malocclusion: A randomized controlled trial.

INTRODUCTION: This 2-arm parallel study aimed to compare and evaluate the efficiency of Hanks Herbst (HH) and Twin-block (TB) functional appliances in treating adolescents with Class II malocclusion. METHODS: A parallel-group randomized controlled trial was undertaken in a single United Kingdom hospital. Eighty participants were recruited and randomized in a 1:1 ratio to receive either the HH or TB appliance. Eligibility criteria included children aged 10-14 years with an overjet of ≥7 mm without dental anomalies. The primary outcome was the time (in months) required to reduce overjet to normal limits (<4 mm). Secondary outcomes included treatment failure rates, complications and their impact on oral health-related quality of life (OHRQOL). Randomization was accomplished using electronic software with allocation concealed using sequentially numbered, opaque, and sealed envelopes. Blinding was only applicable for outcome assessment. Data were analyzed using descriptive statistics and regression analyses to detect between-group differences, including Cox regression for time to treatment success. RESULTS: HH was significantly faster than TB in reducing the overjet to within normal limits (95% confidence interval [CI], -3.00 to -0.03; P = 0.046). Mean overjet reduction was more efficient with the HH than the TB appliance (ß = 1.3; 95% CI, 0.04-2.40; P = 0.04). Fifteen (37.5%) of the participants in the TB group and 7 (17.5%) in the HH group failed to complete the treatment (hazard ratio = 0.54; 95% CI, 0.32-0.91, P = 0.02). However, TB was associated with fewer routine (incidence rate ratio = 0.81; 95% CI, 0.7-0.9; P = 0.004) and emergency (incidence rate ratio = 0.1; 95% CI, 0.1-0.3; P = 0.001) visits. Chairside time was greater with the HH (ß = 2.7; 95% CI, 1.8-3.6, P = 0.001). Participants in both groups experienced complications with similar frequency. A greater deterioration in OHRQOL was found during treatment with the TB. CONCLUSIONS: Treatment with HH resulted in more efficient and predictable overjet reduction than TB. More treatment discontinuation and greater deterioration in OHRQOL were observed with the TB. However, HH was associated with more routine and emergency visits. REGISTRATION: ISRCTN11717011. PROTOCOL: The protocol was not published before trial commencement. FUNDING: No specific external or internal funding was provided. Treatment for participants was provided as part of routine orthodontic treatment in the hospital.

A qualitative evaluation of attitudes toward extractions among primary care orthodontists in Great Britain.

INTRODUCTION: The need to extract permanent teeth as part of orthodontic treatment has been keenly debated over many decades. Changes in the frequency of extraction have been well documented; however, we continue to lack an understanding of what influences clinicians' decisions regarding extracting permanent teeth. METHODS: Purposive sampling was undertaken to obtain representative views from primary care practitioners across Great Britain with a range of experience representing genders and wide geographic distribution. Twenty participants (9 female, 11 male) took part in in-depth, qualitative, 1-to-1 interviews based on a piloted topic guide. Interviews were conducted via video conferencing software with audio recording and verbatim transcription. Thematic analysis was performed with discussion and agreement to identify the main themes. RESULTS: Five main themes were identified: (1) patient-related factors, such as age and features of the malocclusion, (2) operator factors, including the level of experience, (3) setting, with regard to geographic location and method of remuneration, (4) mechanical approaches, including variations in appliance systems; and (5) self-directed ongoing education, including both formal continuing professional development and informal learning from peers. These factors acted as barriers, enablers, or both in relation to nonextraction treatment. CONCLUSIONS: Five key influences on extraction decisions among orthodontists in Great Britain were identified. Extraction choices appear to be influenced by various interrelated factors, evolving over time and with increased experience.

Knowledge assessment on cleft lip and palate among recently graduated dentists: a cross-sectional study.

BACKGROUND: The complex presentation, associated co-morbidities and multi-disciplinary requirements dictate the requirement for in-depth knowledge in order to effectively manage patients with cleft lip and palate (CLP). We aimed to develop a validated questionnaire for cleft lip and palate knowledge assessment and to evaluate the knowledge of cleft lip and palate among a group of recently-graduated dentists. MATERIALS AND METHODS: A multiple-site, cross-sectional questionnaire-based study was conducted. The study population included recently graduated dentists involved in a dental internship program. A bespoke questionnaire was developed and validated, with internal consistency assessed using Cronbach's alpha and factor analysis performed. A 47-item prototype was distilled into a 15-item questionnaire. This was distributed to the participants with a response rate of 67% obtained. RESULTS: The overall proportion of correct responses among dental interns was moderate (73%). The best results were found in relation to CLP treatment including the effect of unfavorable surgical outcomes on speech (89.5%) and the impact of CLP on the occlusion (87.6%). The lowest rate of correct responses (26.7%) was identified in relation to the association between CLP and smoking. CONCLUSION: A validated CLP questionnaire was developed, permitting evaluation of the knowledge of cleft lip and palate and its management among recently graduated dentists. There is limited appreciation among dental interns of the risk factors for CLP as well as post-surgical complications. Given that general dentists are often the gatekeepers for the management of patients with cleft lip and palate, it is important that the findings of this survey are used to inform the curriculum and teaching of cleft lip and palate.

The influence of nasal deviation on the perception of maxillary dental centreline and smile aesthetics.

OBJECTIVE: To assess the impact of nasal deviation on the perception of the maxillary dental centreline position as judged by orthodontists, dentists and laypersons. DESIGN: Cross-sectional study. SETTING: Barts and the London School of Medicine and Dentistry, Queen Mary University of London, UK. PARTICIPANTS: Three groups of raters comprising 30 orthodontists, 30 dentists and 30 laypersons. METHODS: A frontal photograph of a smiling white woman was captured and digitally manipulated with varying degrees of nasal deviation and dental centreline (DC) position in increments of 1.5 mm and 3 mm to the right and left. Three rater groups assessed the attractiveness of images using a visual analogue scale (VAS). Multiple regression analysis was undertaken, and images were compared using the Tukey HSD method. RESULTS: Using a mixed linear model, the intraclass correlation coefficient (ICC) was estimated in the range of 69%-86%, indicating good inter-rater reliability. The interaction between image rating and nasal position (P < 0.001), DC position (P < 0.001) and the relationship between nose and DC position (P < 0.001) were found to be statistically significant with symmetrical upper midline and nasal tip position, both considered to be most aesthetically pleasing. Image rating was not influenced by rater group type (P = 0.995), age (P = 0.983) or sex (P = 0.476). CONCLUSION: There was a preference for a central and coincident nose and maxillary DC position uniformly across the rater groups. Deviations of the nose, DC and their interactions negatively impacted on perceived smile aesthetics with increasing extent and opposing direction of deviations rated progressively more unaesthetic. No differences were observed between orthodontists, general dental practitioners and lay people with respect to perceived impact on smile aesthetics.

Clear aligner therapy practice among orthodontists in the United Kingdom and the Republic of Ireland: A cross-sectional survey of the British Orthodontic Society membership.

OBJECTIVE: To investigate clear aligner therapy (CAT) practice among orthodontists in the British Orthodontic Society (BOS). DESIGN: A cross-sectional online survey. METHODS: An electronic survey was distributed to members of the BOS in 2022. The survey comprised questions regarding respondent demographics, general use of CAT, the choice of proprietary CAT appliances, CAT planning, case selection, treatment protocols and orthodontist-reported CAT problems. RESULTS: Overall, 233 (19.5%) responses were received with the majority (n = 121, 53.1%) being female. Most respondents reported practising in England (n = 171, 74.7%). The majority (n = 177, 77.3%) indicated that they used CAT in their practice, with 48.1% (n = 81) treating 1-20 patients with CAT annually. The most frequently prescribed CAT system was Invisalign (n = 138, 81.2%). One to three changes to the initial digital treatment plan were made by 72.9% (n = 121) with final tooth positions being the most common reason for adjustment (64.4%). Most (n = 97, 60.3%) rarely or never performed premolar extractions with CAT. Of the respondents, 23 12.7%) reported that they always or mostly used a remote monitoring system in conjunction with CAT, with a wide range of aligner change protocols reported. The median number of months required to complete non-extraction CAT reported by the respondents was 12. Most respondents (n = 77, 51.7%) did not feel that CAT provides superior outcomes compared with fixed appliance therapy. CONCLUSION: CAT practice varied widely among the surveyed orthodontists. A predilection for the use of Invisalign and utility in less severe cases was noted.

The effectiveness of a bespoke mobile application in improving adherence with removable orthodontic retention over 12 months: A randomized controlled trial.

INTRODUCTION: The primary aim was to analyze the effect of providing a mobile application (My Retainers) on adherence with removable retention. METHODS: Eighty-four participants planned for thermoplastic retainers were randomly allocated to 2 groups. The intervention group was given access to a bespoke mobile application, while the control group was not given access. Baseline data were obtained at the removal of orthodontic appliances with follow-up at 3 months, 6 months, 9 months, and 12 months. The primary outcome was objectively assessed retainer wear recorded using a TheraMon microelectronic sensor (MC Technology GmbH, Hargelsberg, Austria). Secondary outcomes were stability and periodontal implications. RESULTS: The objectively assessed wear time at 12 months was low in both groups, being marginally higher in the intervention (median, 3.09 h/d; interquartile range, 8.1) than the control group (median, 1.44 h/d; interquartile range, 9.22) with no between-group statistical difference (P = 0.30, 95% confidence interval [CI], -3.91 to 1.19). No statistically significant difference was identified between the groups in terms of stability and periodontal outcomes. Improvement in plaque scores (P <0.0001; 95% CI, -0.20 to 0.15) and bleeding on probing (P <0.0001, 95% CI, -0.23 to -0.12) was noted over time with no periodontal attachment loss detected over the study period. CONCLUSIONS: Provision of the mobile application did not lead to improved adherence with thermoplastic retainer wear. Similarly, no benefit in respect of either occlusal stability or periodontal health was observed over the 12-month study period. Further novel approaches to improve adherence with retainer wear and oral hygiene measures are required. REGISTRATION: NCT03224481. PROTOCOL: Not published. FUNDING: This work was supported by funding from the European Orthodontic Society.

The influence of mobile applications and social media-based interventions in producing behavior change among orthodontic patients: A systematic review and meta-analysis.

INTRODUCTION: The objective of this project was to systematically review the effectiveness of mobile applications and social media-based interventions in producing a behavioral change in orthodontic patients. METHODS: Electronic databases and reference lists of relevant studies were searched on March 1, 2021, with no language restrictions (PROSPERO: CRD42019157298). Randomized and nonrandomized controlled trials assessing the impact of mobile applications and social media-based interventions on orthodontic patients were identified. Primary outcomes included adherence to wear, appointment attendance, knowledge, oral health-related behaviors, oral hygiene levels, periodontal outcomes, and related iatrogenic effects. The quality of the included trials was assessed using the Cochrane risk of bias tools. A weighted treatment effect of interventions on periodontal outcomes was calculated. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system. RESULTS: A total of 3617 articles were identified. Of these, 16 studies (14 randomized controlled trials and 2 nonrandomized controlled trials) were deemed eligible. Nine randomized controlled trials were judged to be of either low or unclear risk of bias. The intervention was favored in relation to gingival and plaque indexes, standardized mean difference: -0.81 (95% confidence intervals [CI], -1.35 to -0.28) and -0.91 (95% CI, -1.64 to -0.19), respectively. However, no significant effect was observed in bleeding on probing (standardized mean difference: -0.22; 95% CI, -0.5 to 0.05). The level of evidence was high in probing depth and bleeding on probing outcomes. CONCLUSIONS: A very low to moderate level of evidence supports the effects of mobile applications and social media-based interventions in producing positive behavioral changes in orthodontic patients. Further high-quality trials would assist in further elucidating the potential of these approaches to influence orthodontic treatment outcomes and experiences.

An assessment of root stage of canine and premolar teeth at alveolar eruption.

OBJECTIVE: The primary aim was to evaluate the degree of root development of permanent canines at the time of alveolar eruption. We also aimed to assess whether differences in the degree of root development at alveolar eruption exist between permanent canines and premolars and between maxilla and mandible. DESIGN: A cross-sectional study. SETTING: Barts and The London School of Medicine and Dentistry, Queen Mary University of London. PARTICIPANTS: Two hundred dental panoramic radiographs taken as part of routine dental care. METHODS: Radiographs were assessed for canine and premolar root development stage and eruption level with calibration and repeat measurements undertaken. RESULTS: Two hundred and sixty teeth were identified as being at the level of alveolar eruption. The majority of maxillary canines reached alveolar eruption when root formation was complete. Most premolars and mandibular canines reached alveolar eruption when roots were three-quarters developed. At alveolar eruption, canines were statistically more mature than premolars (p<0.001) and maxillary teeth were more mature than mandibular teeth (p<0.05). CONCLUSIONS: Root development appears to be particularly advanced for maxillary permanent canines, being essentially root-complete at alveolar eruption, while premolars and mandibular permanent canines appear to have three-quarters root development at this stage. This information may be used to inform whether and when to extract primary teeth for orthodontic reasons.

A cross-sectional evaluation of the impact of Class II Division 1 malocclusion in treated and untreated adolescents on oral health-related quality of life.

INTRODUCTION: The relationship between malocclusion, orthodontic treatment, and oral health-related quality of life (OHRQOL) is complicated, with some traits, such as increased overjet, having a potentially greater adverse effect on an adolescent's OHRQOL. The aim of this study was to evaluate the impact of malocclusion and orthodontic treatment on OHRQOL in adolescents presenting with Class II Division 1 malocclusion and explore the relationship between OHRQOL using a condition-specific and generic instrument and occlusal outcome. METHODS: Two groups of adolescents were recruited from a United Kingdom university hospital: a pretreatment group of adolescents with Class II Division 1 malocclusion and a treated (posttreatment) group whose Class II Division 1 malocclusion had been corrected. Self-reported OHRQOL was assessed using the malocclusion impact questionnaire (MIQ) and the short form of Child Oral Health Impact Profile questionnaires. Occlusion severity and outcome were assessed using Peer Assessment Rating scores. RESULTS: A total of 241 participants (106 male; 135 female) were recruited. MIQ scores differed significantly between the pretreatment and posttreatment groups, with scores being 11.35 times lower posttreatment than pretreatment, after adjusting for age and sex (95% confidence interval, -17.28 to -5.42; P <0.001). Females had higher total MIQ scores by 2.6 (95% confidence interval, 0.38 to 4.82), which was statistically significant (P = 0.022). There was a moderate correlation between MIQ and Peer Assessment Rating scores, but this relationship strengthened when omitting the global MIQ questions (Spearman's correlation coefficient, 0.59). CONCLUSIONS: Increased overjet was associated with impaired OHRQOL using a condition-specific measure. A deeper understanding of associations between malocclusion, orthodontic treatment, and OHRQOL would benefit from longitudinal evaluation.

A prospective evaluation of factors affecting occlusal stability of Class II correction with Twin-block followed by fixed appliances.

INTRODUCTION: Modified Twin-block therapy followed by fixed appliances (TBFA) is a standard treatment modality in Class II malocclusion; however, there is little information regarding the stability of this approach. We aimed to assess the stability of Class II correction with TBFA and to evaluate factors that may affect stability. METHODS: A prospective evaluation involving convenience sampling of 64 participants treated with TBFA was undertaken over 12 months. Study models and lateral cephalometric radiographs were obtained to record overjet and molar relationship, Peer Assessment Rating score, and skeletal parameters, and a new objective buccal segment interdigitation scoring system was developed. Multivariate logistic regression analysis was used to assess the stability of anteroposterior occlusal correction and the degree of buccal interdigitation, pretreatment skeletal discrepancy, and change in overjet during treatment. RESULTS: Mean overjet reduction of 6.22 mm arose during treatment, with the canine and molar relationships improving by 3.34 mm and 2.67 mm, respectively. In the 12 months posttreatment, a relapse of 0.67 mm and 0.06 mm in overjet and molar relationship, respectively, was observed, with 25% of subjects having overjet relapse of >1 mm. There is weak evidence that the treatment-induced change in overjet is linked with overjet relapse (P = 0.05; odds ratio, 0.67; 95% confidence interval, 0.44, 1.01). No significant relationship was observed, however, between anteroposterior stability and buccal segment interdigitation (P = 0.99), pretreatment skeletal discrepancy (P = 0.10) or prescribed retention regime (P = 0.63). CONCLUSIONS: Overall, acceptable levels of stability were observed, although appreciable relapse was noted in 25% of participants. Neither the degree of buccal segment interdigitation nor pretreatment skeletal discrepancy was predictive of anteroposterior occlusal stability.

Complications, impacts, and success rates of different approaches to treatment of Class II malocclusion in adolescents: A systematic review and meta-analysis.

INTRODUCTION: We aimed to explore the prevalence and nature of complications associated with Class II correctors in adolescents and their impact on the quality of life (QOL), completion of treatment, and success rate. METHODS: The review was registered in PROSPERO, and a comprehensive electronic search was performed without language or date restrictions. Randomized and nonrandomized trials, prospective cohort and cross-sectional studies, case series, and qualitative research were included. The Cochrane Collaboration's risk of bias tool and the Newcastle-Ottawa scale were used to assess the quality of included studies. Data were grouped according to appliances design: removable functional, fixed functional, hybrid functional, headgear, and fixed maxillary molar distalization appliances. RESULTS: Data from 27 studies were included, of which 11 were deemed eligible for meta-analysis. Overall, 1676 adolescents were included related to fixed functional (n = 682), removable functional (n = 682), hybrid functional (n = 84), headgear (n = 186), and Carriere (n = 42) appliances. The mean number of emergencies was 0.8 (95% confidence interval [CI], 1.1-2.1) and 2 (95% CI, 0.9-3.0) for removable and fixed designs, respectively. However, the rate of discontinuation was 35% (95% CI, 0.28-0.42) and just 1% (95% CI, 0.01-0.1) for removable and fixed designs, respectively. Other QOL dimensions such as eating, sleep, speech, and emotional domains were significantly impaired during treatment with removable functional appliances. CONCLUSIONS: Removable Class II correctors were associated with a high rate of treatment discontinuation, most likely because of the negative impact on QOL and lack of compliance. More complications were observed with fixed designs, although this did not impact the overall success rates. Further prospective studies are needed to explore patient perceptions and cost-effectiveness to inform treatment decisions better.

Development of a core outcome set for use in routine orthodontic clinical trials.

INTRODUCTION: A diverse range of outcomes is used in orthodontic research with a focus on measuring outcomes important to clinicians and little consistency in outcome selection and measurement. We aimed to develop a core outcome set for use in clinical trials of orthodontic treatment not involving cleft or orthognathic patient groups. METHODS: A list of outcomes measured in previous orthodontic research was identified through a scoping literature review. Additional outcomes of importance to patients were obtained using qualitative interviews and focus groups with adolescents aged 10-16 years. Rating of outcomes was carried out in a 2-round electronic Delphi process involving health care professionals and patients using a 9-point scale. A face-to-face meeting was subsequently held with stakeholders to discuss the results before refining the core outcome set. RESULTS: After triangulation, a final list of 34 outcomes grouped under 10 domains was obtained for rating in the e-Delphi surveys. Fifteen outcomes were voted "in" after the second Delphi round involving 274 participants with a further outcome being included after the consensus meeting. These were subsequently refined into a final set of 7 core outcomes, including the impact of self-perceived esthetics, alignment and/or occlusion, skeletal relationship, stability, patient-related adherence, breakages, and adverse effects on teeth or teeth-supporting structures. CONCLUSIONS: A bespoke orthodontic core outcome set encompassing both clinician- and patient-focused outcomes was developed. Incorporating this is the first step into providing a more holistic assessment of the impact of treatment while allowing for meaningful comparisons and synthesis of results from individual trials.

A priori power considerations in orthodontic research: a 3 year meta-epidemiologic study.

AIM: To assess the prevalence of a priori power calculations in orthodontic literature and to identify potential associations with a number of study characteristics, including journal, year of publication and statistical significance of the outcome. MATERIALS AND METHODS: The electronic archives of four leading orthodontic journals with the highest impact factor (American Journal of Orthodontics and Dentofacial Orthopedics, AJODO; European Journal of Orthodontics, EJO; Angle Orthodontist, ANGLE; Orthodontics and Craniofacial Research, OCR) were assessed over a 3 year period until December 2018. The proportion of articles reporting a priori power calculations were recorded, and the association with journal, year of publication, study design, continent of authorship, number of centres and researchers, statistical significance of results and reporting of confidence intervals (CIs) was assessed. Univariable and multivariable regression were used to identify significant predictors. RESULTS: Overall, 654 eligible articles were retrieved, with the majority published in the AJODO (n = 246, 37.6%), followed by ANGLE (n = 222, 33.9%) and EJO (n = 139, 21.3%). A total of 233 studies (35.6%) presented power considerations a priori along with sample size calculations. Study design was a very strong predictor with interventional design presenting 3.02 times higher odds for a priori power assumptions compared to observational research [odds ratio (OR): 3.02; 95% CIs: 2.06, 4.42; P < 0.001]. CONCLUSIONS: Presentation of a priori power considerations for sample size calculations was not universal in contemporary orthodontic literature, while specific study designs such as observational or animal and in vitro studies were less likely to report such considerations.