Ephrin Ligands and Eph Receptors Show Regionally Restricted Expression in the Developing Palate and Tongue

The Eph family receptor-interacting (ephrin) ligands and erythropoietin-producing hepatocellular carcinoma (Eph) receptors constitute the largest known family of receptor tyrosine kinases. Ephrin ligands and their receptors form an important cell communication system with widespread roles in normal physiology and disease pathogenesis. In order to investigate potential roles of the ephrin-Eph system during palatogenesis and tongue development, we have characterized the cellular mRNA expression of family members EphrinA1-A3, EphA1–A8 and EphrinB2, EphB1, EphB4 during murine embryogenesis between embryonic day 13.5–16.5 using radioactive in situ hybridization. With the exception of EphA6 and ephrinA3, all genes were regionally expressed during the process of palatogenesis, with restricted and often overlapping domains. Transcripts were identified in the palate epithelium, localized at the tip of the palatal shelves, in the mesenchyme and also confined to the medial epithelium seam. Numerous Eph transcripts were also identified during tongue development. In particular, EphA1 and EphA2 demonstrated a highly restricted and specific expression in the tongue epithelium at all stages examined, whereas EphA3 was strongly expressed in the lateral tongue mesenchyme. These results suggest regulatory roles for ephrin-EphA signaling in development of the murine palate and tongue

Does the quality of orthodontic studies influence their Altmetric Attention Score?

OBJECTIVE The aim of this study was to determine whether an association between study quality, other study characteristics, and Altmetric Attention Scores (AASs) existed in orthodontic studies. METHODS The Scopus database was searched to identify orthodontic studies published between January 1, 2017, and December 31, 2019. Articles that satisfied the eligibility criteria were included in this study. Study characteristics, including study quality were extracted and entered into a pre-pilot data collection sheet. Descriptive statistics were calculated. On an exploratory basis, random forest and gradient boosting machine learning algorithms were used to examine the influence of article characteristics on AAS. RESULTS In total, 586 studies with an AAS were analyzed. Overall, the mean AAS of the samples was 5. Twitter was the most popular social media platform for publicizing studies, accounting for 53.7%. In terms of study quality, only 19.1% of the studies were rated as having a high level of quality, with 41.8% of the studies deemed moderate quality. The type of social media platform, number of citations, impact factor, and study type were among the most influential characteristics of AAS in both models. In contrast, study quality was one of the least influential characteristics on the AAS. CONCLUSIONS Social media platforms contributed the most to the AAS for orthodontic studies, whereas study quality had little impact on the AAS

Clinical evaluation of marketed and non-marketed orthodontic products: are researchers now ahead of the times? A meta-epidemiological study.

BACKGROUND The advertisement and adoption of untested orthodontic products is common. This study aimed to provide an update regarding the prevalence of clinical trials in orthodontics evaluating commercially marketed products. Associations between marketed/non-marketed products and study characteristics such as direction of effect, declaration of conflict of interest and industry sponsorship were evaluated. In addition, within the marketed products associations between direction of effect and study characteristics were explored. MATERIAL AND METHODS Electronic searching of a single database (Medline via PubMed) was undertaken to identify Randomized controlled trials (RCTs) published over a 5-year period (1st January 2017 to 31st December 2021). Descriptive statistics and associations between trial characteristics were explored. RESULTS 196 RCTs were analysed. RCTs were frequently published in Angle Orthodontist (18.4%), American Journal of Orthodontics and Dentofacial Orthopedics (14.8%) and European Journal of Orthodontics (13.3%). 65.3% (128/196) of trials assessed marketed products after their introduction. The majority of trials assessed interventions to improve treatment efficiency (33.7%). Growth modification appliances were typically analysed in non-marketed compared to marketed products. An association between the type of product (marketed vs non-marketed) and both the declaration of conflict of interest and industry sponsorship was detected. For individual RCTs assessing marketed products either a positive effect (45.3%) or equivalence between interventions or between intervention and untreated control (47.7%) was evident. In 27% of these trials either no conflict of interest or industry funding was not clearly declared. Within the marketed products, no association between the direction of the effect and conflict of interest or funding was detected. CONCLUSIONS The analysis of marketed orthodontic products after their introduction is still common practice. To reduce research waste, collaboration prior to the licensing and marketing of orthodontic products between researchers, industry and manufacturers is recommended

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

Do we get better outcomes from early treatment of Class III discrepancies

Early orthodontic treatment in the mixed dentition aims to simplify definitive treatment in the permanent dentition. In Class III cases, this can be an effective strategy for the management of a local anterior crossbite, using either a removable or simple fixed appliance. For more significant Class III malocclusions, the decision to intervene early is a more difficult one. Traditionally, orthodontists in the UK have been reluctant to embark on early treatment in the presence of a skeletal Class III relationship but there is now some evidence that in selected cases, the use of protraction headgear can be a successful method of avoiding the need for later surgery. Although growth prediction in Class III cases is notoriously difficult, in the presence of maxillary retrognathia, the general dental practitioner should consider early referral of Class III cases to a specialist orthodontist

Should we recommend early overjet reduction to prevent dental trauma

There is an association between increased overjet and risk of trauma to the maxillary incisor teeth in children and adolescents. It would therefore seem sensible to recommend overjet reduction as early as possible to help reduce this risk. However, orthodontic outcomes are essentially the same whether you start treatment in the early or late mixed dentition, while early treatment carries a heavier burden on compliance - taking longer and involving more appointments. This article explores the complex association between early overjet reduction and dental trauma in the context of current best evidence. Careful case selection is advised when justifying early intervention for increased overjet based on reducing trauma risk

Do we get better outcomes from early treatment of Class III discrepancies?

Early orthodontic treatment in the mixed dentition aims to simplify definitive treatment in the permanent dentition. In Class III cases, this can be an effective strategy for the management of a local anterior crossbite, using either a removable or simple fixed appliance. For more significant Class III malocclusions, the decision to intervene early is a more difficult one. Traditionally, orthodontists in the UK have been reluctant to embark on early treatment in the presence of a skeletal Class III relationship but there is now some evidence that in selected cases, the use of protraction headgear can be a successful method of avoiding the need for later surgery. Although growth prediction in Class III cases is notoriously difficult, in the presence of maxillary retrognathia, the general dental practitioner should consider early referral of Class III cases to a specialist orthodontist

Registered trials report less beneficial treatment effects than unregistered ones:A meta-epidemiological study in orthodontics

Dataset and commands for all analyses in the study