Molecular profiling of the vestibular lamina highlights a key role for Hedgehog signalling.

The vestibular lamina (VL) forms the oral vestibule, creating a gap between the teeth, lips and cheeks. In a number of ciliopathies, formation of the vestibule is defective, leading to the creation of multiple frenula. In contrast to the neighbouring dental lamina, which forms the teeth, little is known about the genes that pattern the VL. Here, we establish a molecular signature for the usually non-odontogenic VL in mice and highlight several genes and signalling pathways that may play a role in its development. For one of these, the Sonic hedgehog (Shh) pathway, we show that co-receptors Gas1, Cdon and Boc are highly expressed in the VL and act to enhance the Shh signal from the forming incisor region. In Gas1 mutant mice, expression of Gli1 was disrupted and the VL epithelium failed to extend due to a loss of proliferation. This defect was exacerbated in Boc/Gas1 double mutants and could be phenocopied using cyclopamine in culture. Signals from the forming teeth, therefore, control development of the VL, coordinating the development of the dentition and the oral cavity.

The prevalence of and factors influencing statistical testing of baseline characteristics in randomized controlled trials published in high-impact orthodontic journals.

INTRODUCTION: When proper randomization has been undertaken, statistical testing of baseline characteristics between participants in trial arms in randomized controlled trials (RCTs) is not required. This investigation aimed to assess the prevalence of statistical testing of baseline differences in orthodontic RCTs. Factors influencing the undertaking of this analysis were explored. METHODS: Orthodontic RCTs published between January 1, 2017 and December 31, 2021 in 5 orthodontic journals were identified. To determine if statistical testing of baseline differences had been undertaken, each article was reviewed in detail to identify the reporting of P values and the term "significant difference" in the table of characteristics, the table legends, and the results section of each included RCT. Trial characteristics at the RCT level were extracted. Frequency distributions were calculated for the included trial characteristics. Significant predictors from the univariate analysis were used to construct a multivariable Bayesian logistic regression model. RESULTS: One hundred and thirty-two RCTs were analyzed. Significance testing of baseline characteristics was undertaken in 50% (66/132) of RCTs. At a journal level, significance testing at baseline was infrequently undertaken in RCTs published in the American Journal of Orthodontics and Dentofacial Orthopedics (AJODO). Compared with 2017, RCTs published in 2018 (odds ratio [OR], 5.57; 95% credible interval [CrI], 1.33-25.69), 2019 (OR, 17.82; 95% CrI, 4.41-82.11), 2020 (OR, 6.48; 95% CrI, 1.72-27.12), and 2021 (OR, 3.24, 95% CrI, 0.81-14.01) had higher odds of significance testing at baseline. RCTs published in the European Journal of Orthodontics (OR, 5.31; 95% CrI, 1.79-17.04), Progress in Orthodontics (OR, 5.00; 95% CrI, 0.97-28.43), Orthodontics and Craniofacial Research (OR, 6.49; 95% CrI, 1.04-46.10), and Angle Orthodontist (OR, 12.30; 95% CrI, 3.27-51.44) had higher odds of significant testing at baseline testing compared with AJODO. CONCLUSIONS: Statistical testing of baseline differences is common in orthodontic RCTs. Trials published in AJODO had the lowest incidence of statistical testing of baseline differences. RCTs published between 2018-2021 had higher odds of significance testing at baseline than in 2017. Per the consolidated standards of reporting trials guidelines, this practice should be discouraged as it can be misleading and unnecessary.

Duration of canine retraction with fixed appliances: A systematic review and meta-analysis.

INTRODUCTION: Space closure is a challenging and time-consuming phase of orthodontic treatment with fixed appliances. This systematic review evaluated canine retraction duration using fixed appliances after maxillary first premolar extraction. METHODS: Unrestricted systematic literature searches were conducted in 8 databases for randomized clinical trials, assessing the duration and rate of maxillary canine retraction using fixed appliances with or without treatment adjuncts published up to July 2021. Study selection, data extraction, and risk of bias evaluation were conducted independently and in duplicate. Random-effects meta-analyses of average rates or mean differences (MD) and 95% confidence intervals (CI) were conducted at α = 5%, followed by sensitivity and Grading of Recommendations Assessment, Development, and Evaluation analysis. RESULTS: Fifty randomized clinical trials (6 parallel and 44 split-mouth designs) covering 811 participants (mean age 19.9 years; 34% male) were included. The estimated average pooled duration to achieve complete canine retraction was 4.98 months (2 trials; 95% CI, -2.9 to 12.88 months). Pooled average canine retraction was 0.97 mm at months 0-1 (23 trials; 95% CI, 0.79-1.16), 1.83 mm at months 0-2 (20 trials; 95% CI, 1.52-2.14), 2.44 mm at months 0-3 (23 trials; 95% CI, 2.10-2.79), 3.49 mm at months 0-4 (6 trials; 95% CI, 1.81-5.17) and 4.25 mm at months 0-5 (2 trials; 95% CI, 0.36-8.14). Surgically-assisted orthodontics was associated with greater canine retraction at all time points: months 0-1 (10 trials; MD, 0.52 mm; P = 0.004), months 0-2 (8 trials; MD, 0.53 mm; P = 0.04), months 0-3 (8 trials; MD, 0.67 mm; P = 0.01), and months 0-4 (3 trials; MD, 1.13 mm; P = 0.01), whereas subgroup analyses indicated significant effects of anchorage reinforcement method and bracket slot size on canine retraction. CONCLUSIONS: The average time to achieve complete retraction of the maxillary canine using fixed appliances was around 5.0 months. Most studies used split-mouth randomization to investigate canine retraction for around 1-3 months, with substantial heterogeneity across studies. At 3 months of treatment, high-quality evidence supported greater canine retraction with surgically-assisted orthodontics.

Interventions to facilitate the successful eruption of impacted maxillary incisor teeth due to the presence of a supernumerary: A systematic review and meta-analysis.

INTRODUCTION: A failure of maxillary incisor eruption is commonly attributed to the presence of a supernumerary tooth. This systematic review aimed to assess the percentage of impacted maxillary incisors that successfully erupt after surgical removal of supernumerary teeth with or without other interventions. METHODS: Systematic literature searches without restrictions were undertaken in 8 databases for studies reporting any intervention aimed at facilitating incisor eruption, including surgical removal of the supernumerary alone or in conjunction with additional interventions published up to September 2022. After duplicate study selection, data extraction, and risk of bias assessment according to the risk of bias in nonrandomized studies of interventions and Newcastle-Ottawa scale, random-effects meta-analyses of aggregate data were conducted. RESULTS: Fifteen studies (14 retrospective and 1 prospective) were included with 1058 participants (68.9% male; mean age, 9.1 years). The pooled eruption prevalence for removal of the supernumerary tooth with space creation or removal of the supernumerary tooth with orthodontic traction was significantly higher at 82.4% (95% confidence interval [CI], 65.5-93.2) and 96.9% (95% CI, 83.8-99.9) respectively, compared with removal of an associated supernumerary only (57.6%; 95% CI, 47.8-67.0). The odds of successful eruption of an impacted maxillary incisor after removal of a supernumerary were more favorable if the obstruction was removed in the deciduous dentition (odds ratio [OR], 0.42; 95% CI, 0.20-0.90; P = 0.02); if the supernumeraries were conical (OR, 2.91; 95% CI, 1.98-4.28; P <0.001); if the incisor was in the correct position (OR, 2.19; 95% CI, 1.14-4.20; P = 0.02), at the level of the gingival third (OR 0.07; 95% CI, <0.01-0.97; P = 0.04) and had incomplete root formation (OR, 9.02; 95% CI, 2.04-39.78; P = 0.004). Delaying removal of the supernumerary tooth 12 months after the expected eruption time of the maxillary incisor (OR, 0.33; 95% CI, 0.10-1.03; P = 0.05) and waiting >6 months for spontaneous eruption after removal of the obstacle (OR, 0.13; 95% CI, 0.03-0.50; P = 0.003) was associated with worse odds for eruption. CONCLUSIONS: Limited evidence indicated that the adjunctive use of orthodontic measures and removal of supernumerary teeth might be associated with greater odds of successfull impacted incisor eruption than removal of the supernumerary tooth alone. Certain characteristics related to supernumerary type and the position or developmental stage of the incisor may also influence successful eruption after removal of the supernumerary. However, these findings should be viewed with caution as our certainty is very low to low because of bias and heterogeneity. Further well-conducted and reported studies are required. The results of this systematic review have been used to inform and justify the iMAC Trial.

Accounting for clustering is still not routinely undertaken in orthodontic studies.

BACKGROUND: The aim of this study was to identify studies with clustering effects published in orthodontic journals and to assess the frequency by which clustered designs are correctly accounted for in the statistical analysis. Factors associated with appropriate management of clustering effects during the statistical analysis were explored. MATERIALS AND METHOD: A search of three leading orthodontic journals was undertaken to identify studies with clustering effects published between 1 January 2019 and 31 December 2021. Descriptive statistics and frequency distributions were calculated. Associations between the correct statistical handling of clustering effects and study characteristics were explored via univariable and multivariable analyses. RESULTS: Three hundred and sixty-two studies were considered to have clustering effects. Only 22.4 per cent of studies correctly accounted for clustering effects in the statistical analysis with no improvement compared to a previous study in 2012 using the same journals. An association between the use of the correct analysis to account for clustering and the following study characteristics was detected: involvement of statistician, study type, significance of the results, and accounting for clustering in the sample size calculations. In the univariable analysis, interventional studies, non-significant results, and the involvement of a statistician were associated with higher odds of the use of the correct analysis. Of the studies correctly accounting for clustering, the most used tests were repeated measures ANOVA (43.3 per cent) and mixed models (40.7 per cent). CONCLUSIONS: Compared to previous research, there appears to be no improvement in accounting for clustering effects in studies published in orthodontic journals. To prevent incorrect inferences being drawn, clustering effects need to be recognised and accounted for in orthodontic studies. Recommendations to improve the accounting of clustering effects, at both the study level and during the statistical analysis are suggested.

Periodontal outcomes associated with impacted maxillary central incisor and canine teeth following surgical exposure and orthodontic alignment: a systematic review and meta-analysis.

BACKGROUND: Maxillary incisor and canine teeth are commonly impacted and require multidisciplinary treatment to accommodate them in the dental arch. OBJECTIVES: To assess the periodontal outcomes of impacted maxillary central incisor and canine teeth, which have been successfully aligned in the arch following surgical exposure and orthodontic traction with fixed appliance therapy. SEARCH METHODS: Systematic literature searches without restrictions were undertaken in eight databases. SELECTION CRITERIA: Studies reporting surgical interventions in combination with orthodontic traction with fixed appliance therapy to align impacted maxillary incisors or canines published up to January 2023. DATA COLLECTION: Duplicate independent study selection, data extraction, and risk of bias assessment. ANALYSIS: Random-effects meta-analyses of aggregate data. RESULTS: Twenty-three studies (21 retrospective and 2 prospective) were included in the final analysis. Three studies reported outcomes for maxillary central incisors and 20 reported outcomes for maxillary canines. For maxillary central incisors, all three studies were rated as being at moderate risk of bias. For maxillary canines, 17 studies and 1 study were rated at moderate and high risk of bias, respectively. Both prospective studies were rated at a low risk of bias. Meta-analyses comparing aligned impacted maxillary canines to their non-impacted contralateral counterparts found the former had increased Plaque Index scores (mean difference [MD] 0.19; 95% confidence interval [CI] 0.03, 0.35; P = 0.03), increased clinical attachment loss (MD 0.40 mm; 95% CI 0.17, 0.63; P = 0.01), increased pocket probing depth (MD 0.18 mm; 95% CI 0.07, 0.28; P = 0.001), increased bone loss (MD 0.51 mm; 95% CI 0.31, 0.72; P < 0.001), and reduced keratinized gingival width (MD -0.31 mm; 95% CI -0.61, -0.01; P = 0.04). CONCLUSIONS: Limited evidence suggests that surgical exposure and orthodontic alignment of impacted maxillary central incisor or canine teeth, results in modest adverse effects in the periodontium. These findings should be viewed with caution as our certainty for these outcomes is very low to low due to the bias and heterogeneity. Further well-conducted studies reporting patient centred outcomes are required. REGISTRATION: PROSPERO (CRD42020225639).

Orthodontic clinicians' attitudes and knowledge of dentogingival aesthetics: A cross-sectional survey of BOS members.

OBJECTIVE: To assess orthodontic clinicians' knowledge and attitudes towards dentogingival aesthetics and to explore characteristics that predict the knowledge of dentogingival aesthetics. DESIGN: Cross-sectional questionnaire. SETTING: On-line survey of members of the British Orthdontic Society. MATERIALS AND METHODS: An 11-item online questionnaire was sent to orthodontic practitioners for completion. The questionnaire covered respondent demographics and questions relating to both knowledge and attitudes towards dentogingival aesthetics (six parameters). Descriptive statistics were calculated for study characteristics and summary values for the survey items. Responses to the eight knowledge-based questions were converted to a binary outcome (correct and incorrect answer). The maximum score that could be achieved was eight. Multivariable modelling was used in order to examine associations between the study characteristics and the aggregate score. RESULTS: A total of 252 responses were obtained resulting in a response rate of 17%. Within this cohort, the respondents were primarily women (52.8%) and aged 30-40 years (35.7%). The mean score for the eight knowledge-based questions was 3.8 ± 1.8 (range = 0-8). Knowledge of the ideal gingival margin position of the anterior teeth was high (92.4%). Knowledge of the other five dentogingival aesthetic parameters was variable. In the multivariable analysis, lower knowledge scores were predicated by respondents who did not have a special interest in dental aesthetics (-0.54; 95% confidence interval [CI] = -1.01 to -0.07; P = 0.02), who could not recall attending courses, lectures or seminars on dental aesthetics in the past five years (-0.80; 95% CI = -1.43 to -0.17; P = 0.01) and with increasing age (-0.43; 95% CI = -0.62 to -0.23; P < 0.001). CONCLUSION: Knowledge of ideal dentogingival parameters is generally suboptimal among orthodontists in the UK. The reported lack of knowledge of the ideal dentogingival parameters may also influence respondents' attitudes towards the importance of dentogingival aesthetics. Further teaching or courses related to dentogingival aesthetics is desired by orthodontic clinicians.

Temporospatial sonic hedgehog signalling is essential for neural crest-dependent patterning of the intrinsic tongue musculature.

The tongue is a highly specialised muscular organ with a complex anatomy required for normal function. We have utilised multiple genetic approaches to investigate local temporospatial requirements for sonic hedgehog (SHH) signalling during tongue development. Mice lacking a Shh cis-enhancer, MFCS4 (ShhMFCS4/-), with reduced SHH in dorsal tongue epithelium have perturbed lingual septum tendon formation and disrupted intrinsic muscle patterning, with these defects reproduced following global Shh deletion from E10.5 in pCag-CreERTM; Shhflox/flox embryos. SHH responsiveness was diminished in local cranial neural crest cell (CNCC) populations in both mutants, with SHH targeting these cells through the primary cilium. CNCC-specific deletion of orofaciodigital syndrome 1 (Ofd1), which encodes a ciliary protein, in Wnt1-Cre; Ofdfl/Y mice led to a complete loss of normal myotube arrangement and hypoglossia. In contrast, mesoderm-specific deletion of Ofd1 in Mesp1-Cre; Ofdfl/Y embryos resulted in normal intrinsic muscle arrangement. Collectively, these findings suggest key temporospatial requirements for local SHH signalling in tongue development (specifically, lingual tendon differentiation and intrinsic muscle patterning through signalling to CNCCs) and provide further mechanistic insight into the tongue anomalies seen in patients with disrupted hedgehog signalling.

Dental anomalies in non-syndromic orofacial clefts: A clinical approach.

Orofacial clefts (OC) represent some of the most common congenital malformations and affect multiple structures in the craniofacial region. There are a wide range of morphological OC types within the spectrum of both non-syndromic OC (NSOC) and syndromic OC, including cleft lip (CL), cleft lip and palate, (CLP), and cleft palate (CP). Here, we describe the most frequent dental anomalies seen in the permanent dentition of individuals with NSOC, comparing them between the three main cleft types (CL, CLP, and CP). We present these findings from the perspective of prevalence relating to each anomaly, as well as the clinical characteristics and potential impact on the rehabilitation process. The investigation of dental anomalies associated with NSOC is important, helping to expand the phenotypic characterization of NSOC, improve the initial diagnostics, and establish appropriate rehabilitation and counseling.

Prolific authorship in orthodontic scientific publishing.

OBJECTIVES: To identify the 10 most numerically prolific authors publishing in the field of orthodontics for each year over the last decade (2011-2020), describe the characteristics of these outputs and identify trends in the types of study being published. MATERIALS AND METHODS: A Scopus literature search was conducted to identify the 10 most numerically prolific publishing authors in orthodontics for each year during this decade. Number and characteristics of all publications for each author were analysed with descriptive and inferential statistics. RESULTS: Forty-nine different individual authors were identified who were collectively prolific for between 1-8 years within the assessment decade. These authors published a total of 2025 papers, with a median annual output of 18 papers per year; however, half of these authors published between 15-24 papers per year (range 5-200). Amongst authors, 2 or more collaborated on only 7% of the identified papers. The median number of authors per paper was 5 (range 1-27) with significant variation according to study design (P < .001). The majority of authors originated from Brazil (19.3%), Italy (14.1%) and India (12.7%). Most papers described non-prospective clinical studies (38.1%), case reports or case series (11.1%) and narrative reviews (10.8%). Finally, prolific authors had a smaller annual output when publishing in orthodontic journals (P < .001) and when publishing experimental primary research (P = .04). CONCLUSIONS: A cohort of prolific authors in orthodontics between 2011-2020 was identified. Extreme variation was found in annual output between these authors but case reports, non-prospective clinical studies and narrative reviews predominated.

Salivary bacterial community profile in normal-weight and obese adolescent patients prior to orthodontic treatment with fixed appliances.

OBJECTIVES: The aim of this study was to compare the intra-oral bacterial profile of normal-weight and obese adolescents prior to orthodontic treatment with fixed appliances. MATERIALS AND METHODS: Nineteen adolescent patients were recruited into two groups based upon body mass index (BMI) and classified as normal-weight or obese. Unstimulated whole mouth saliva was obtained for 5 minutes. Bacterial DNA extraction was performed from saliva, and 16S rRNA gene sequencing of the V1-2 variable regions was undertaken followed by analysis using the mothur pipeline. RESULTS: Saliva from a total of 19 adolescent patients with mean (SD) age 15.6 (1.8) years were divided into 10 normal-weight with mean BMI of 19.4 (2.2) kg/m2 and 9 obese with mean BMI of 30.2 (3.5) kg/m2 . A total of 156 783 sequences were obtained from the 19 samples with no significant differences in richness or diversity between sample groups by obesity status or gender (AMOVA). The bacterial community in both groups was dominated by bacterial genera characteristic of the human mouth, which included Streptococcus, Porphyromonas, Veillonella, Gemella, Prevotella, Fusobacterium and Rothia. CONCLUSION: There were no differences in alpha or beta diversity of oral bacterial communities between normal-weight and obese orthodontic patients. Obese adolescents attending for orthodontic treatment had a similar microflora to their normal-weight counterparts.

What you read is what you get: Are orthodontic randomized clinical trials correctly titled?

INTRODUCTION: Because of their importance in health care research, randomized controlled trials (RCTs) should be correctly labeled in the title to ensure it reflects the methodologic standards undertaken. This study aimed to assess whether orthodontic RCTs are correctly titled RCTs, and trial characteristics that influence correct labeling in titles were explored. METHODS: Orthodontic RCTs published between January 1, 2015 and September 30, 2020 in 7 orthodontic journals were identified. For a trial to be considered an RCT, random allocation sequence generation and allocation concealment mechanisms should be reported in the study methodology. Trial characteristics at the RCT level were extracted, and frequency distributions were calculated for the included trial characteristics. A 2-stage continuation ratio ordinal logistic regression model was used to assess associations between the dependent variable (non-RCT, unclear, RCT) and the trial characteristics. RESULTS: One-hundred and seventy-three RCTs were analyzed. Of these, 112 (64.7%) were assessed as true RCTs, with 109 (64.1%) correctly labeled as RCTs. The American Journal of Orthodontics and Dentofacial Orthopedics (AJODO) published the most trials that were correctly labeled as RCTs (90.5%). In the adjusted model, the type of journal influenced the correct labeling, with all journals compared with AJODO having lower odds of correct RCT classification. Multicenter trials were associated with higher odds of being correctly labeled as an RCT. CONCLUSIONS: Compared with previous investigations, the correct labeling of orthodontic RCTs in the title of the report has improved substantially. The type of journal and multicenter trials influenced the correct labeling of a trial as an RCT. The number and odds of RCTs being correctly labeled as RCTs were higher in trials published in AJODO.

Duration of tooth alignment with fixed appliances: A systematic review and meta-analysis.

INTRODUCTION: A key goal of orthodontic treatment with fixed appliances is alignment of the dentition, and this remains a commonly selected outcome in clinical studies investigating orthodontic tooth movement. This systematic review has evaluated treatment duration to achieve alignment of the mandibular dentition using fixed appliances. METHODS: Systematic literature searches without restrictions were undertaken in 9 databases for randomized clinical trials (RCTs) assessing duration and rate of tooth alignment using fixed appliances with or without treatment adjuncts published up to January 2021. After duplicate study selection, data extraction, and risk of bias assessment according to Cochrane, random-effects meta-analyses of aggregate data, and individual patient data were conducted. RESULTS: Thirty-five trials were included with 2258 participants (39% male; mean age 17.8 years), giving a pooled duration to achieve whole-arch alignment of the mandibular dentition of 263.0 days (4 trials; 95% confidence interval [CI], 186.7-339.4 days) and incisor alignment in the mandibular arch of 100.7 days (9 trials; 95% CI, 84.1-117.4 days). Surgical-assisted orthodontics was associated with reduced duration of incisor alignment: mean difference of 44.3 days less (4 trials; 95% CI, 20.0-68.9 days; P <0.001; high quality of evidence), whereas subgroup and meta-regression analyses indicated significant effects of baseline crowding and premolar extractions. Individual patient data analysis from 3 RCTs indicated that for each additional participant age year, whole-arch alignment of the mandibular dentition took 13.7 days longer (3 trials; 95% CI, 7.7-17.7 days; P <0.001) and for each additional mm of irregularity, 17.5 days more were needed (2 trials; 95% CI, 9.8-25.2 days; P <0.001). CONCLUSIONS: Patient and treatment-related characteristics can significantly affect the duration of tooth alignment and should be taken into account both clinically and when designing trial outcomes. Future research studies investigating rates of orthodontic tooth alignment would benefit from adequate sample sizes and a more consistent methodology in outcome assessment. Data in this systematic review provides a basis for appropriate trial design for future RCTs investigating the rate of orthodontic tooth alignment with fixed appliances.

What are the differences in protective characteristics of orthodontic mouthguards? An in vitro study.

BACKGROUND: Orthodontic patients wearing fixed appliances are susceptible to traumatic dental injuries during contact-sport. This laboratory study investigated the protective qualities of orthodontic mouthguards using impact-testing to a typodont fitted with a fixed appliance through peak load transfer and retention of the mouthguard. METHODS: Seven orthodontic mouthguards [three custom-made (Medium-CM, Heavy-CM, Heavy-pro-CM); three commercially-available mouth-formed (Shock-Doctor® Ultra Braces, Opro® Ortho-Gold Braces, Opro® Ortho-Bronze Braces) and a Shock-Doctor® Instant-Fit] were fitted to a maxillary arch typodont bonded with a fixed appliance and impact-tested using 0.5 or 1 Joule (J) energy via hockey-ball, cricket-ball or steel-ball projectile. A load-cell recorded peak load transfer through mouthguard to typodont with retention scored in a binary manner dependent upon any displacement following impact. Differences across mouthguards were calculated with ANOVA or Kruskal-Wallis test for normal and non-normal data, respectively. Post hoc comparisons across mouthguards were conducted via Dunnett's test with Sidak correction. RESULTS: Only the three custom-made and Opro® Ortho-Gold Braces were not displaced by impact-testing. For these, Opro® Ortho-Gold Braces transferred the smallest load for 3/6 impact-tests, followed by Medium-CM. Heavy-pro-CM performed poorly, ranking penultimate or worst for all impact-tests. Significant differences were found between mouthguards for cricket-ball and steel-ball set-ups. The Opro® Ortho-Gold Braces performed better than the Heavy and Heavy-pro-CM for 0.5 J cricket-ball impact-test (P < 0.05), whilst Medium-CM performed better than Heavy-pro-CM. For 1 J cricket-ball, there were significant differences between Medium-CM and Heavy-pro-CM (P < 0.05). For 0.5 J steel-ball, the Medium-CM performed significantly better than both Heavy-pro-CM and Opro® Ortho-Gold Braces (P < 0.05), whilst Heavy-CM performed better than the Heavy-pro-CM (P < 0.05). For the 1 J steel-ball, Medium and Heavy-CM performed better than Opro® Ortho-Gold Braces (P < 0.05). CONCLUSIONS: Opro® Ortho-Gold and Medium-CM mouthguards offer the best protection for low-impact sports, whilst Medium or Heavy-CM mouthguards are recommended for high-impact sport.

Wearability and preference of mouthguard during sport in patients undergoing orthodontic treatment with fixed appliances: a randomized clinical trial.

BACKGROUND: Orthodontic patients wearing fixed appliances are susceptible to traumatic dental injuries during a wide range of sporting activities. This randomized clinical trial investigated wearability and preference of mouthguards during sporting activities in patients undergoing orthodontic treatment with fixed appliances. METHODS: A prospective three-arm crossover randomized clinical trial conducted in the UK. Thirty patients in active orthodontic treatment with fixed appliances undertaking at least 120 minutes of contact sport per 6-8-week observation period were randomly assigned to one of six mouthguard allocation sequences consisting of three mouthguard types: (MG1) custom-made laboratory constructed, (MG2) mouth-formed OPRO® Gold Braces, and (MG3) pre-fabricated Shock Doctor® Single Brace. Patients completed a nine-outcome 100-mm visual analogue scale (VAS) questionnaire relating to mouthguard wearability during sport. Once feedback was completed, subjects were allocated the next mouthguard in the sequence. At study-end, subjects were asked to identify their preferred mouthguard. RESULTS: Twenty-four patients (median age = 13; inter-quartile range 12-14.5 years) completed n = 72 follow-up questionnaires with most playing rugby union or field hockey. Considering VAS score as a continuous variable, for comfort, stability, hardness, ability to breathe, ability to not cause nausea, and inclination to chew, MG2 performed better than MG3. For categorization of VAS score into low (less than 80 mm) or high (at least 80 mm) wearability, for comfort, stability, ability to not cause nausea, and inclination to chew, MG1 and MG2 also rated superior to MG3. Patients preferred MG1 overall. CONCLUSIONS: This randomized clinical trial found that during contact sport patients in fixed appliances reported superior wearability for custom-made and mouth-formed mouthguards in comparison to pre-fabricated. Overall, patients preferred custom-made mouthguards. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov: NCT04588831.

Peer Assessment Rating (PAR) scoring of cleft patients treated within a regional cleft centre in the United Kingdom.

OBJECTIVE: To assess static occlusal outcomes for patients with cleft lip and/or palate (CLP) and cleft palate (CP) managed within a UK Regional Cleft Service and to compare with previously published Peer Assessment Rating (PAR) scores from a non-cleft population of patients treated within a UK consultant-led hospital service. DESIGN: Retrospective multicentre study. SETTING: Eight orthodontic hospital units within the Spires Cleft Service, UK. PARTICIPANTS: Patients born with CLP or CP between 1985 and 1995 treated within the service. METHODS: Patients were assigned to groups by cleft type and whether they were treated by orthodontics only or a combination of orthodontics and orthognathic surgery. PAR was recorded before and after treatment from study models. RESULTS: Data were collected for 171 patients included in the study. Median pre-treatment PAR was 42 and post-treatment 11. Median percentage change in PAR for all patients was 73%, although 12% of cleft patients had a PAR improvement that was worse or no different. Median change in PAR score was 71% for those treated with orthodontics only and 83% for those who had an osteotomy. Median PAR improvement for those treated with orthodontics only was 73% in the cleft lip group, 77% in the CP group, 66% in the unilateral CLP group and 53% in the bilateral CLP group. Median pre- and post-treatment PAR for the cleft group was higher and PAR reduction lower than those published for non-cleft patients. CONCLUSION: These data demonstrate high severity of malocclusion, complexity of orthodontic treatment and difficulty in achieving an ideal static occlusion for cleft patients. If PAR is to be used to assess orthodontic outcomes in cleft patients the findings of this study should be considered. A higher proportion of cases are likely to be classed as 'worse or no different', and a lower percentage change will be expected.

A cross-sectional study of exposure across social media platforms for the British Orthodontic Society retention awareness campaign: #HoldthatSmile.

OBJECTIVE: The use of media campaigns in health promotion has become more common in recent years. #HoldthatSmile is a British Orthodontic Society life-long retention awareness campaign aimed at the general public and dental profession launched in 2017. This study investigated #HoldthatSmile exposure on social media platforms over a 12-month period following campaign launch. DESIGN: A cross-sectional content analysis. SETTING: Public-facing, English-language posts tagged #HoldthatSmile on the Facebook, Instagram and Twitter social media platforms. METHODS: Data were collected relating to a 12-month period, from September 2017 immediately following campaign launch, to the end of September 2018. The primary outcome was exposure to the #HoldthatSmile campaign on the different platforms through analysis of posts, measurement of audience reached and engagement. Secondary outcomes included demographics of user-types and content analysis of reactive comments on posts. RESULTS: A total of 205 relevant posts with #HoldthatSmile were identified on Twitter (n=90, 43.9%), Facebook (n=64, 31.2%) and Instagram (n=51, 24.9%) with an overall calculated audience reach of 108,807 individuals. There were 1849 reactions across the three platforms. The percentage of reactions that generated comments was low at 3%, 6.1% and 5.7% for Twitter, Facebook and Instagram, respectively. Just over three-quarters of users were either Dental Surgeries (53%) or Professional Dental Bodies (28%) and the vast majority were from the United Kingdom. Overall, most comments were positive (46%, n=36) or neutral (44%, n=35) with only 10% (n=8) negative. The overriding theme was a person's name, with the user commonly typing a friend's name in order to bring their attention to the post. CONCLUSION: There were a relatively low number of posts relevant to #HoldthatSmile on Twitter, Facebook and Instagram over the campaign's first 12 months. However, the majority of these did convey positive or neutral messages.

How to make a tongue: Cellular and molecular regulation of muscle and connective tissue formation during mammalian tongue development.

The vertebrate tongue is a complex muscular organ situated in the oral cavity and involved in multiple functions including mastication, taste sensation, articulation and the maintenance of oral health. Although the gross embryological contributions to tongue formation have been known for many years, it is only relatively recently that the molecular pathways regulating these processes have begun to be discovered. In particular, there is now evidence that the Hedgehog, TGF-Beta, Wnt and Notch signaling pathways all play an important role in mediating appropriate signaling interactions between the epithelial, cranial neural crest and mesodermal cell populations that are required to form the tongue. In humans, a number of congenital abnormalities that affect gross morphology of the tongue have also been described, occurring in isolation or as part of a developmental syndrome, which can greatly impact on the health and well-being of affected individuals. These anomalies can range from an absence of tongue formation (aglossia) through to diminutive (microglossia), enlarged (macroglossia) or bifid tongue. Here, we present an overview of the gross anatomy and embryology of mammalian tongue development, focusing on the molecular processes underlying formation of the musculature and connective tissues within this organ. We also survey the clinical presentation of tongue anomalies seen in human populations, whilst considering their developmental and genetic etiology.

Quantitative investigation of the esthetic impact of lip prominence in relation to the esthetic line.

INTRODUCTION: The purpose of this quantitative investigation was to assess the influence of lip prominence in relation to the esthetic line (E-line) on perceived attractiveness and threshold values of desire for treatment. METHODS: The lip prominence of an idealized silhouette male white profile image was altered incrementally between -16 mm to 4 mm from the E-line. The images were rated on a Likert scale by pretreatment orthognathic patients (n = 75), laypeople (n = 75), and clinicians (n = 35). RESULTS: In terms of perceived attractiveness, lips to E-line distance within the ranges of -12 mm to -16 mm and 0-4 mm in relation to the E-line was associated with a reduction in median attractiveness scores to below 4 in the patient and clinician groups of observers; for the lay group, the corresponding ranges were -14 mm to -16 mm and 2-4 mm. Relative lip prominence appears to be viewed as more attractive than lip retrusion. Clinicians were generally least likely to suggest treatment for varying levels of bilabial position. For a number of the images, there was reasonable agreement among clinicians and laypeople regarding whether treatment is required. For the clinician group, the only categories for desire for treatment were at a lip to E-line distance within the ranges of -14 mm to -16 mm and 2-4 mm. CONCLUSIONS: It is recommended that the range of normal variability of the prominence of the lips and threshold values of the desire for treatment be considered in planning.

Product advertisements in orthodontic journals: Are they evidence-based?

INTRODUCTION: Previous research has suggested orthodontic advertisements are poorly supported by evidence. The primary aim of this study was to identify the type and quality of evidence supporting advertisement claims in leading orthodontic journals. METHODS: A cross-sectional study was undertaken to assess all advertisements published between January 2015 and December 2017 in 6 major orthodontic journals. Only advertisements implying superior product performance in clinical practice or patient care were selected for further evaluation. Study variables were collected using a prespecified data collection form. In the presence of a supporting citation, the reference article was obtained, and the quality was assessed in duplicate. Associations between advertisement variables and quality of evidence were explored using contingency tables (Fisher exact test). RESULTS: A total of 1753 advertisements were identified. After the application of eligibility criteria, 124 were included in the final analysis. Advertisements promoting bracket systems predominated. Of these, 34.7% were supported by evidence, of which 10.5% (n = 13) included accessible references. Only 6 out of 13 studies involved orthodontic patients. Primarily expert opinion and observational study types were referenced. Less than 2% of advertisements were supported by high-value evidence. There was an association between the quality of evidence in advertisements and the product category (P = 0.003). CONCLUSIONS: There is a lack of both references and high-value evidence cited in orthodontic manufacturers' advertisements. Without critical appraisal of references cited in advertisements, clinicians need to be cautious before implementing manufacturers' recommendations in clinical practice. Efforts should be made to ensure appropriate high-value evidence is cited in advertisements to support manufacturers' claims.