Comparison of treatment effects between clear aligners and fixed appliances in patients treated with miniscrew-assisted molar distalization.

OBJECTIVES: The biomechanics in achieving molar distalization may differ between fixed appliances and clear aligners in the control of tooth movement. The objective of this study was to compare the treatment effects between clear aligners (CA) and fixed appliances (FA) in patients treated with miniscrew-assisted molar distalization. METHODS: The sample consisted of 46 subjects with mild-to-moderate crowding. A total of 22 patients treated with clear aligners (age, 25.66 ±â€…6.11 years old) and 24 patients treated with fixed appliances (age, 24.04 ±â€…4.95 years old) for miniscrew-assisted molar distalization were included in this study. The dental and skeletal changes were evaluated by the pre- and post-treatment lateral cephalograms. RESULTS: Significant changes were found with the vertical variables SN-OP angle (2.24 ±â€…3.22°, P < .05) and SN-MP angle (0.73 ±â€…1.15°, P < .05) for the FA group when compared with the CA group (SN-OP angle 0.41 ±â€…2.26° and SN-MP angle -0.21 ±â€…1.38°, P > .05). Both treatment groups achieved a 2-3 mm. molar distalization with significant intrusion of the upper molars. The CA group showed significantly less distal tipping of molars (U6^PP angle -2.29 ±â€…3.29° and L6^MP angle -2.92 ±â€…2.49°, P < .05) compared to the FA group (-5.24 ±â€…4.28° and -5.53 ±â€…5.03°, P < .05). In addition, significant retraction and lingual inclination of the upper and lower incisors were found in both groups. LIMITATIONS: The changes of tooth position were evaluated by 2D lateral cephalograms, not 3D measurements. CONCLUSIONS: Compared to fixed appliances, clear aligners seemed to have better control of vertical dimension and distal tipping of molars in patients treated with miniscrew-assisted molar distalization.

Clear aligner's adverse effects: A systematic review protocol.

With the growing popularity of clear aligners, more patients have chosen to use them instead of traditional orthodontic braces to correct their malocclusions. Clear aligners offer distinct advantages over conventional fixed braces, such as limited aesthetic impact, the convenience of easily removing them for meals, improved accessibility for brushing and flossing, and a treatment approach that avoids the use of metal, minimizing potential irritation to the cheeks and gums. Manufacturers point out a disadvantage that can be administered in this type of treatment. Still, to our knowledge, a comprehensive review of the published literature assessing the adverse/negative effects of clear aligners has not yet been conducted. A systematic review, with or without meta-analysis, will be performed. The inclusion criteria will be studies involving individuals using clear aligners and reporting potential adverse/negative effects during or after treatment. No restrictions about time or language will be applied. The studies screening will be conducted in two stages. Two independent reviewers will initially evaluate the title and abstract under the eligibility criteria. Subsequently, the same two reviewers will examine the articles' full text in-depth. The results will be synthesized in the form of a narrative description and incorporate a meta-analysis if justified. Furthermore, we will present details regarding the sample characteristics, intervention, study objectives, methodologies employed, and primary findings. This study aims to investigate the potential adverse effects and their frequency among orthodontic patients wearing clear aligners. Moreover, the outcomes of this review have the potential to illuminate specific inherent limitations of aligner therapy as a comprehensive orthodontic approach.

Correlation between general quality of life and oral health related quality in the mixed dentition.

The aim of this study was to evaluate the convergence between the domains of the Autoquestionnaire Qualité de Vie Enfant image (AUQUEI) and the Child Perceptions Questionnaire (CPQ8-10) in the mixed dentition. A sample of 676 children aged 8 to 10 years responded to the health-related quality of life (HRQoL) and oral health-related quality of life (OHRQoL) questionnaires using the AUQUEI and the CPQ8-10, respectively. Clinical (dental caries and malocclusion) and socioeconomic variables were assessed. The validity of convergence between scores (total and per domain) of the two instruments was assessed by Spearman correlation analysis, considering that non-zero coefficient values represented a correlation between scores. The median was calculated to compare the scores of each questionnaire relative to the variables, and the nonparametric Mann-Whitney test was applied to determine statistically significant differences between the categories. A weak significant correlation (between 0.30 and 0.50) was observed between the domains and the total scores of instruments (p < 0.05), except for the leisure domain (p > 0.05). Participants with a lower family income had worse HRQoL (p < 0.05), and those with caries and malocclusion experience had worse OHRQoL (p < 0.05). In conclusion, the AUQUEI and CPQ8-10 instruments showed a weak correlation. Income and clinical variables had a negative impact on the AUQUEI and CPQ8-10, respectively.

[Fractures of the mandibular condyle]. / Fracturen van het collum mandibulae.

A fracture of the mandibular condyle is a common fracture of the mandible. After the diagnosis has been made, there are various treatment options: wait and see, conservative or surgical. Which of these treatment options is best depends on several different factors and is often the subject of debate. A common complication of a fracture of the mandibular condyle is malocclusion. Malocclusion can cause problems - even in the long term - for which the patient often requires secondary treatment.

A novel acrylic orthodontic device for treatment of linguoverted mandibular canine teeth in small dogs.

Linguoverted mandibular canine teeth (LMC) is a common malocclusion in dogs. Several inclined bite-plane techniques using acrylic resin have been introduced to correct LMC in dogs. Although these techniques have suggested modifications to overcome shortcomings, there are still limitations; e.g., high technical sensitivity, as the viscous acrylic resin must still be fabricated in the oral cavity. The authors developed a novel method for small-breed dogs that uses a doughy acrylic resin form to achieve an easy intraoral design and extraoral fabrication. Eight small-breed dogs were presented to evaluate and treat malocclusion causing palatal trauma. First, a Class-1 malocclusion with linguoversion of the mandibular canine teeth (6 dogs with unilateral LMC and 2 dogs with bilateral) was diagnosed based on oral examination. Dogs were treated with the new method using a doughy acrylic resin form for 6 to 7 wk and had posttreatment follow-up 1 y after the procedure. All treated canine teeth were in correct positions 1 y after the appliances were removed. Key clinical message: The authors believe that the new method using a doughy acrylic resin form could be a good alternative for veterinarians to use when treating LMC.

Un nouveau dispositif orthodontique en acrylique pour le traitement des canines mandibulaires linguoverties chez les petits chiens. Les canines mandibulaires linguoverties (LMC) sont une malocclusion courante chez le chien. Plusieurs techniques de plan de morsure incliné utilisant de la résine acrylique ont été introduites pour corriger la LMC chez le chien. Bien que ces techniques aient suggéré des modifications pour surmonter les lacunes, elles présentent encore des limites; par exemple, une sensibilité technique élevée, car la résine acrylique visqueuse doit encore être fabriquée dans la cavité buccale. Les auteurs ont développé une nouvelle méthode pour les chiens de petite race qui utilise une forme pâteuse de résine acrylique pour obtenir une conception intra-orale et une fabrication extra-orale faciles. Huit chiens de petite race ont été présentés pour évaluer et traiter une malocclusion provoquant un traumatisme palatin. Tout d'abord, une malocclusion de classe 1 avec linguoversion des canines mandibulaires (6 chiens avec LMC unilatérale et 2 chiens avec bilatérale) a été diagnostiquée sur la base d'un examen oral. Les chiens ont été traités avec la nouvelle méthode en utilisant une forme pâteuse de résine acrylique pendant 6 à 7 semaines et ont fait l'objet d'un suivi post-traitement 1 an après la procédure. Toutes les canines traitées étaient dans la bonne position un an après le retrait des appareils.Message clinique clé:Les auteurs estiment que la nouvelle méthode utilisant une forme pâteuse de résine acrylique pourrait être une bonne alternative que les vétérinaires pourraient utiliser lors du traitement du LMC.(Traduit par Dr Serge Messier).

Orthognathic surgery: a significant tool for reassessment / La chirurgie orthognathique : un outil à ne pas oublier dans la réévaluation

Introduction: More than 15 years of experience in orthodontic-surgical collaboration has allowed the authors to identify some situations in which a new perspective is needed. Although it may seem easy to refer a patient to a maxillo-facial surgeon in cases of major dysmorphoses, this can lead to yet other dilemmas: a loss of results at the end of a developmental growth stage, an adult requesting a return to treatment after a camouflage orthodontic treatment or a non-cooperative child in an interceptive and preventive treatment phase. Then, a comprehensive process of reassessment becomes compulsory. Material and Method: In the form of an editorial, this article describes various cases encountered in the authors' practice. Discussion: The aim is not to point out the imperfections of our humanity, but simply to open our eyes to diagnostic elements that are missed, whether in the initial phase or during reassessment. Conclusion: As it is far from ideal to keep offering similar therapies that lead to the same pitfalls, it is time for a shift in the paradigm.

Introduction: Plus de 15 ans de recul en collaboration orthodontico-chirurgicale ont permis aux auteurs d'identifier un certain nombre de situations dans lesquelles un regard différent est devenu opportun. S'il est aisé d'orienter un patient vers un(e) chirurgien(ne) maxillo-facial(e) en cas de dysmorphoses majeures, les orthodontistes sont régulièrement confrontés à d'autres dilemmes : une perte de résultat en fin de croissance, un adulte demandeur d'une reprise après un traitement en compensation ou encore un enfant non-coopérant en phase interceptive. Une phase de réévaluation exhaustive devient alors nécessaire. Matériel et méthode: Sous la forme d'un éditorial, cet article expose différentes situations cliniques auxquelles les auteurs ont été confrontés lors de leur pratique. Discussion: Le propos n'est pas de pointer les imperfections de notre humanité mais seulement d'ouvrir les yeux sur des éléments diagnostiques qui échappent, que ce soit en phase initiale ou en réévaluation. Conclusion: Offrir une thérapeutique identique conduisant aux mêmes écueils n'est pas acceptable : il est temps de changer de paradigme.

Tooth-size discrepancy: a clinical necessity / Harmonie dento-dentaire : une nécessité clinique

Introduction: The subject of this article is the discovery of dento-dental disharmony (DDD) at the end of treatment. Lack of diagnosis is the source of this type of disappointment. Material and Method: The diagnosis of DDD is not easily accessible on clinical examination and the compensations it generates mask it, especially if it is associated with other dysmorphoses. The use of indices, the best-known of which is Bolton's, enables diagnosis with the setup, a pre-treatment model which also has many other prognostic interests. Results: Once DDD has been considered, it can be resolved by adapting dental volumes, either by subtraction or addition. Conclusion: Advances in computerized diagnosis with artificial intelligence are opening up new avenues for the systematic diagnosis of DDD.

Introduction: L'objectif de cet article est de présenter, à l'issue de la découverte d'une dysharmonie dento-dentaire (DDD) en fin de traitement orthodontique, les modalités de sa prise en charge. Le défaut de diagnostic initial est la source de ce type de déconvenue. Matériel et méthode: Le diagnostic de la DDD n'est pas facilement accessible à l'examen clinique, les compensations qu'elle génère la masquent, surtout si elle est associée à d'autres dysmorphoses. L'utilisation d'indices, dont le plus connu est celui de Bolton, permet le diagnostic avec le setup, maquette de prétraitement qui a aussi beaucoup d'autres intérêts pronostiques. Résultats: Une fois prise en compte, la DDD trouve sa solution par l'adaptation des volumes dentaires soit par soustraction amélaire soit par addition. Conclusion: Les avancées du diagnostic informatisé avec l'intelligence artificielle ouvrent des portes pour intégrer le diagnostic systématique de la DDD.

Aesthetic perception of patient in developmental age in interceptive orthodontic treatment.

AIM: Patients at development age show considerable attention to the shape of the face from both an aesthetic and relational point of view, to arouse interest from researchers. There are few studies related to profile analysis in patients of developmental age. Therefore, the objective of the present study was to analyse the importance of the aesthetic perception of the patient in development age in relation to the profile, before and after interceptive orthodontic treatment. MATERIALS: A sample of 25 patients who came to our observation for dentoskeletal malocclusions was considered. A questionnaire was proposed to each patient, before and after the interceptive orthodontic treatment (T0 and T1), to evaluate the aesthetic perception before and after the orthodontic treatment and its psychosocial impact. Profile analysis was performed using photographic documentation (at T0 and T1). The variables considered were the Ricketts line, the facial convexity angle, the nasolabial angle, and the labiomental angle. CONCLUSION: Interceptive orthodontic treatment has proven to be of valid clinical and psychological help. This result is confirmed by the complete aesthetic satisfaction of the patient in the frontal and latero-lateral planes.

Accuracy and reliability of magnetic resonance imaging in orthodontic diagnosis and treatment planning-a systematic review and meta-analysis.

BACKGROUND: Magnetic resonance imaging (MRI) is a non-ionizing imaging technique. Using MRI in dentistry may potentially lower the general radiation dose of the examined population, provided MRI can replace various radiation-based images. Furthermore, novel MRI imaging modalities for three-dimensional and two-dimensional cephalometrics have recently been developed for orthodontic diagnosis. OBJECTIVES: This systematic review aimed to determine the diagnostic accuracy and reliability of MRI in orthodontic diagnosis and treatment planning. SEARCH METHODS: An electronic search was conducted on 20 November 2022 in the following databases: PubMed, LILACS, Web of Science, EMBASE, Scopus, and Cochrane. The search was updated on 30 August 2023. Furthermore, a grey literature search was performed in Google Scholar and Open-Grey. SELECTION CRITERIA: This review included descriptive, observational, cohort studies, cross-sectional, case-control studies, and randomized/non-randomized trials related to the research question. The study excluded studies related to patients with syndromes, chronic diseases, craniofacial anomalies, or bone diseases. DATA COLLECTION AND ANALYSIS: The included studies were quality assessed using the "Joanna Brigg's Critical Appraisal Tool for diagnostic test accuracy". The GRADE approach for non-randomized studies was used for strength-of-evidence analysis. RESULTS: Eight of the 10 included studies compared MRI with either cone beam computed tomography or lateral cephalogram and found a high intra- and inter-rater agreement for landmark identification. The risk of bias was high in four studies, moderate in three, and low in three studies. Homogeneity was lacking among the included studies in terms of MRI imaging parameters and sample characteristics. This should be taken into consideration by future studies where uniformity with respect to these parameters may be considered. CONCLUSIONS: Despite dissimilarity and heterogeneity in the sample population and other methodological aspects, all the included studies concluded that MRI enjoyed considerable intra- and inter-examiner reliability and was comparable to current diagnostic standards in orthodontics. Furthermore, the studies agreed on the innovative potential of MRI in radiation-free diagnosis and treatment planning in orthodontics in the future. REGISTRATION: CRD number: CRD420223XXXXX.

[The use of fixed expanders with orthodontic miniscrews support in children with mesial occlusion]. / Ispol'zovanie nes"emnykh rasshiritelei s vnutrikostnoi oporoi u detei s mezial'noi okklyuziei.

OBJECTIVE: Prevention of the development of pronounced skeletal abnormalities in patients with mesial occlusion. MATERIALS AND METHODS: Biometric analysis of control and diagnostic models of dentition was performed in 60 patients with dental anomalies before and after treatment in 3 mutually perpendicular planes to identify violations in the formation of dental arches by sagittal and transversal dimensions, and alveolar processes - by vertical dimensions (methods of A. Pont, G. Korkhaus). Measurements of 23 parameters of TRG and sections of CBCT were carried out using the modified Nad-Ars technique with analysis of skeletal parameters before and after treatment. Treatment was carried out using dilators for the upper jaw in combination with a facial mask and further dynamic observation using active retention devices. RESULTS: The results of treatment showed an increase in the length of the anterior segment of the upper dental arch by 2.8±0.55 mm (p<0.05 mm); expansion in the area of temporary molars by 2.85±0.65 mm (p<0.05); in the area of permanent molars by 2.75±0.55 mm (p<0.05); in the area of the apical basis of HF by 3.82±0.45 mm (p<0.05). The length of the lower dental arch in the anterior segment has not changed. Analysis of TRG parameters showed a significant increase in the values of

[Correlation between combined deflection angle classification adduction typing and complications after internal fixation of adduction femoral neck fracture].

Objective: To analyze the correlation between postoperative complications and combined deflection angle classification adduction type (CDAC-ADT) of femoral neck fractures after cannulated screw internal fixation. Methods: The clinical data of 121 patients with CDAC-ADT femoral neck fracture admitted between January 2018 and December 2021 and met the selected criteria were retrospectively analyzed. There were 69 males and 52 females, the age ranged from 19 to 79 years (mean, 48.1 years). The causes of injury included 52 cases of traffic accident, 24 cases of falling from height, and 45 cases of fall. The time from injury to operation ranged from 2 to 12 days, with an average of 6.0 days. Among them, there were 18 cases of CDAC-ADT type Ⅰ, 46 cases of type Ⅱ, and 57 cases of type Ⅲ; 6 cases of Garden type Ⅱ, 103 cases of type Ⅲ, and 12 cases of type Ⅳ; and according to the location of the fracture line, there were 26 cases of subcapitate type, 88 cases of transcervical type, and 7 cases of basal type. All patients were treated with cannulated screw internal fixation. The occurrence of complications (including internal fixation failure, fracture nonunion, and osteonecrosis of the femoral head) was recorded, and the correlation between complications and CDAC-ADT typing, Garden typing, and fracture line location were analyzed. Results: The patients were followed up 8-44 months, with a mean of 24.9 months. There were 10 cases of internal fixation failure, 7 cases of fracture nonunion, and 30 cases of osteonecrosis of the femoral head after operation. Correlation analysis showed that patients' CDAC-ADT typing was significantly correlated with the overall incidence of complication and the incidence of internal fixation failure, fracture nonunion, and osteonecrosis of the femoral head ( P<0.05), and the Pearson coefficient of contingency were 0.435, 0.251, 0.254, and 0.241, respectively. Garden typing did not correlate with the overall incidence of complication and the incidence of internal fixation failure and fracture nonunion ( P>0.05), but correlated with the incidence of osteonecrosis of the femoral head ( P<0.05), and the Pearson coefficient of contingency was 0.251. Fracture line position typing had no correlation with the overall incidence of complication and the incidence of internal fixation failure, fracture nonunion, and osteonecrosis of the femoral head ( P>0.05). Conclusion: CDAC-ADT typing has obvious correlation with postoperative complications of femoral neck fracture and can be used to predict complications of femoral neck fracture.

Functional therapy and adenotonsillectomy clinical trial for class II malocclusion (FACT-II): protocol for a randomised controlled trial.

INTRODUCTION: Class II malocclusion with mandibular retrognathia is a common complication of paediatric obstructive sleep apnoea (OSA), often accompanied by transverse maxillary deficiency. In early orthodontic treatment, a twin block (TB) is a regular functional appliance for correcting this malocclusion. For paediatric OSA, the most common risk factor is adenotonsillar hypertrophy (AHT). Untreated AHT may lead to the persistence and worsening of obstructive sleep-disordered breathing traits, including habitual mouth breathing. Additionally, the clockwise mandibular rotation associated with AHT-induced pharyngeal crowding can undermine the effectiveness and stability of TB treatment. Adenotonsillectomy (T&A) is currently the first-line treatment for paediatric OSA. This proposed trial will investigate the impact of T&A surgery timing on the efficacy and stability of TB functional treatment in children with class II mandibular retrognathia and ATH. METHODS AND ANALYSIS: This will be a single-centre, parallel-group, superiority randomised controlled trial with participants randomised to intervention (T&A followed by TB treatment) or control arms (TB treatment followed by T&A) in a 1:1 ratio. A total of 40 patients aged 8-14 years, diagnosed with class II mandibular retrognathia and co-existing ATH-induced OSA, and indicated for both T&A surgery and TB treatment, will be recruited at the School and Hospital of Stomatology, Wuhan University. The primary outcomes will be the changes in the apnoea-hypopnoea index and the point A-nasion-point B angle from baseline to postorthodontic treatment between the two groups. Secondary outcomes will include other dental, skeletal, upper airway and soft tissue changes, as well as subjective sleep-related and oral-related quality of life. Outcome changes within each group and between groups will be analysed. ETHICS AND DISSEMINATION: This study is approved by the Ethics Committee of the School and Hospital of Stomatology, Wuhan University (no. 2022-D07). The research findings will be faithfully disseminated through scientific conferences or published articles. TRIAL REGISTRATION NUMBER: ChiCTR2200061703 (https://www.chictr.org.cn).

Optimization of the clinical diagnostic examination algorithm of patients with a cross bite complicated by cranio-mandibular dysfunction and postural disorder.

OBJECTIVE: Aim: Optimization of the clinical and diagnostic examination algorithm of patients with cross bite, aggravated by cranio-mandibular dysfunction and postural disorders. PATIENTS AND METHODS: Materials and Methods: 22 patients aged 13-16 years with cross bite with displacement of the lower jaw were examined. The first group consisted of 15 people with a right-sided displacement of the lower jaw, the second - 7 patients with a left-sided one. The condition of the musculoskeletal system was assessed by the position of the head, shoulders, shoulder blades, back (curvature of the spine), legs, chest shape, and abdomen. To determine the state of stability of the body in space, posturological and kinesiological tests were performed. The location of TMJ elements was evaluated on orthopantomograms. Statistical processing of the material was carried out with the help of the "Excel" license package. RESULTS: Results: 63.64% of patients with a cross bite have disorders of the musculoskeletal system: scoliotic posture - 40.91% and scoliosis - 22.73%. TMJ dysfunction was detected in all examined patients. It was established that the anatomical and topographic features of the joint elements depend on the side of the lower jaw displacement. CONCLUSION: Conclusions: The functional imbalance of all structural elements of the musculoskeletal system and the cranio-mandibular complex determined during the research proved the need to optimize the clinical-diagnostic algorithm: consultation of a traumatologist-orthopedic doctor, X-ray examination of TMJ, conducting posturological tests.

Effects of eruption guidance appliance in the early treatment of Class III malocclusion.

OBJECTIVES: To evaluate the dentoskeletal effects and effectiveness of the eruption guidance appliance in Class III patients in the mixed dentition. MATERIALS AND METHODS: The experimental group comprised 22 patients with Class III malocclusion and anterior cross-bite (12 males, 10 females, mean age 7.63 ± 0.96 years) treated with the eruption guidance appliance over a mean period of 1.72 ± 0.48 years. The control group comprised 22 untreated subjects (12 males, 10 females, mean age 7.21 ± 0.60 years) with Class III malocclusion. Lateral cephalometric radiographs were obtained at pretreatment (T1) and posttreatment (T2). Intergroup comparisons were performed with Mann-Whitney and t-tests (P < .05). RESULTS: In the experimental and control groups, the anteroposterior relationship between the maxilla and mandible (ANB angle) remained stable during the treatment period (T1 to T2). The mandibular plane angle decreased in the experimental group and increased in the control group. In the experimental group, the lower anterior face height increase and maxillary molar vertical development were significantly smaller compared to controls. Positive overjet was achieved in 54% of the experimental group. CONCLUSIONS: The eruption guidance appliance produced no change in the skeletal anteroposterior relationship. The anterior cross-bite/edge-to-edge relationship was corrected in only about half of the treated subjects.

Relationship Between Dentofacial Features and Bullying in School children.

Purpose: The purpose of this cross-sectional study was to evaluate the association between clinician-assessed (actual) and self-assessed (perceived) dentofacial features and their association with bullying in schoolchildren. Methods: The sample comprised 519 schoolchildren aged 10 to 12 years old (235 boys and 284 girls) randomly selected from private and public schools. Clinical evaluations were performed to record dento- facial features, and the children were asked a self-reported questionnaire about their personal experience of bullying and perceived dentofacial features. Descriptive statistics (counts and percentages) as well as chi-square to analyze the association between variables were applied. Results: The results showed that 57.2 percent of the children reported being bullied, and the mainly perceived dentofacial features cited were: "crooked teeth" (46.3 percent), "shape or color of teeth" (45.5 percent), "upper front teeth sticking out" (43.8 percent), and "having a gap between the teeth or having missing teeth" (35.5 percent). Statistically significant associations between actual and perceived dentofacial features and involve- ment in bullying were observed for anterior crowding (P=0.01), anterior crossbite (P<0.001), lip competence (P=0.008), and anterior dental trauma (P=0.04). Conclusion: Some actual and perceived dentofacial traits are associated with bullying, so these features and the schoolchil- dren's compliances should be considered to determine the treatment need.

Basal and dentoalveolar transverse parameters in different sagittal and vertical malocclusions in adults: a comparative study.

OBJECTIVE: This study sought to three-dimensionally (3D) evaluate the maxillomandibular basal bone and dentoalveolar widths using cone-beam computed tomography (CBCT) scans in adult Chinese populations with different vertical and sagittal facial skeletal patterns whilst no apparent posterior dental crossbite. MATERIALS AND METHODS: The retrospective cross-sectional comparative study enrolled CBCT images of 259 adult patients (125 males and 134 females). The subjects were divided into the hyperdivergent(n = 82), hypodivergent(n = 88), and normodivergent(n = 89) groups based on the Jarabak ratio (S-GO/N-Me), which were further divided into three subgroups of skeletal Class I, II and III, based on both the ANB angle and AF-BF parameters. ANOVA was used to analyze the extracted data of the studied groups. The intra- and inter-observer reliability was analyzed using the intra-class correlation coefficient (ICC). RESULTS: In all three vertical facial skeletal patterns, the skeletal Class II had significantly smaller mandibular basal bone width compared to skeletal Class I and Class III, both at the first molar and first premolar levels. The skeletal Class III seemed to have smaller maxillary basal bone width compared to skeletal Class I and Class II malocclusions; however, a significant difference was found only in the normodivergent pattern. As for the dentoalveolar compensation, it was most notable that in the hypodivergent growth pattern, the skeletal Class II had significantly smaller maxillary dentoalveolar width compared to the Class I and Class III groups, both at the first molar and first premolar levels. CONCLUSIONS: Based on the sample in the present study, skeletal Class II has the narrowest mandibular basal bone regardless of the vertical facial skeletal pattern. CLINICAL RELEVANCE: For Chinese adults with no apparent transverse discrepancy, the maxillomandibular basal bone and dentoalveolar widths are revealed in specific categories based on different vertical and sagittal facial skeletal patterns. In diagnosis and treatment planning, particular attention should be paid to skeletal Class II for possibly existing mandibular narrowing.

Effectiveness of a low-intensity static magnetic field in accelerating upper canine retraction: a randomized controlled clinical trial.

INTRODUCTION: Neodymium-iron-boron magnets have been suggested as a contemporary method for accelerating the process of orthodontic tooth movement (OTM). A limited number of clinical trials evaluated their effectiveness in accelerating OTM which is desirable for both orthodontists and patients. The present study aimed to investigate the effectiveness of a low-intensity static magnetic field (SMF) in accelerating upper canine retraction movement. MATERIALS AND METHODS: Seventeen patients (mean age 20.76 ± 2.9 years) with their orthodontic treatment decision to extract the upper and lower first premolars due to bimaxillary protrusion malocclusion were included in this split-mouth study. Canine retraction was performed using Nickel-titanium (Ni-Ti) closed-coil springs (150 g of force on each side). The experimental side received SMF via an auxiliary wire that carried 4-neodymium iron-born magnets with an air gap of 2 mm between the magnets to produce a magnetic field density of 414 mT in the region corresponding to the lateral ligament of the upper canine. To determine the rate of upper canine retraction and upper molar drift, alginate impressions were taken once a month to create plaster casts, which were analyzed digitally via a three-dimensional method. RESULTS: The rate of upper canine retraction was significantly greater (P < 0.05) on the SMF side than that on the control side during the first and second months, with an overall duration (19.16%) that was greater than that on the control side. The peak acceleration occurred during the second month (38.09%). No significant differences in upper molar drift were detected between the experimental and control sides (P > 0.05). CONCLUSION: A low-intensity static magnetic field was effective at accelerating upper canine retraction. The difference between the two sides was statistically significant but may not be clinically significant. The SMF did not affect upper molar drift during the upper canine retraction phase. TRIAL REGISTRATION: The trial was retrospectively registered at the ISRCTN registry ( ISRCTN59092624 ) (31/05/2022).

Expert consensus on pediatric orthodontic therapies of malocclusions in children.

Malocclusion, identified by the World Health Organization (WHO) as one of three major oral diseases, profoundly impacts the dental-maxillofacial functions, facial esthetics, and long-term development of ~260 million children in China. Beyond its physical manifestations, malocclusion also significantly influences the psycho-social well-being of these children. Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition, by mitigating the negative impact of abnormal environmental influences on the growth. Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development, ranging from fetal stages to the early permanent dentition phase. From an economic and societal standpoint, the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated, underlining its profound practical and social importance. This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children, emphasizing critical need for early treatment. It elaborates on corresponding core principles and fundamental approaches in early orthodontics, proposing comprehensive guidance for preventive and interceptive orthodontic treatment, serving as a reference for clinicians engaged in early orthodontic treatment.

Three-dimensional assessment of upper airway changes associated with mandibular positional deviations following fibula free flap reconstruction.

OBJECTIVES: Fibula free flaps (FFF) are the standard approach to mandibular reconstruction after partial resection, with the goal of restoring aesthetics and masticatory function. The graft position affects both and must be carefully selected. Correlations between sagittal positioning and upper airway anatomy are known from orthognathic surgery. This study aims to evaluate changes in mandibular position and upper airway anatomy after reconstructive surgery with FFF and corresponding correlations. MATERIALS AND METHODS: Mandibular position after reconstruction was evaluated using three-dimensional datasets of pre- and postoperative computed tomography scans of patients treated between 2020 and 2022. Three-dimensional measurements were performed on both condyles and the symphyseal region. Changes in upper airway volume and minimum cross-sectional area (minCSA) were analysed. Intra-rater reliability was assessed. Correlations between changes in upper airway anatomy and sagittal mandibular position were tested. RESULTS: The analysis included 35 patients. Intra-rater reliability was good to excellent. Condylar deviations and rotations were mostly rated as small. Changes in symphyseal position were considerably greater. Median airway volume decreased in the oropharynx and hypopharynx. Posterior deviation of the symphysis was associated with a decreasing minCSA in the hypopharynx and vice versa. CONCLUSIONS: The overall accuracy of mandibular reconstructions with FFF is high, but there is room for optimization. The focus of research should be extended from masticatory to respiratory rehabilitation. CLINICAL RELEVANCE: Effects on respiratory function should be considered prior to graft positioning. The clinical relevance of upper airway changes within the complex rehabilitation of reconstructive surgery patients needs to be further investigated.

Cranial Base Measurements in Skeletal Malocclusion among Orthodontic Patients.

BACKGROUND: Facial growth and development is necessary for proper orthodontic diagnosis and treatment planning. Growth of cranial base is linked to the overall growth of facial bones, especially the maxilla and mandible. Any change in the amount and direction of growth of the cranial base can have direct or indirect effects on the developing maxilla and mandible. Thus the aim of this study was to determine the linear and angular cranial base measurements in different skeletal malocclusion in Nepalese population. METHODS: Pretreatment lateral cephalograms of 225 patients aged between 17-30 years were collected. Linear measurements Sella-Nasion (S-N), Sella-Articulare (S-Ar), Articulare-Gonion (Ar-Go), Gonion-Gnathion (Go-Gn) and angular measurements Saddle angle (N-S-Ar), Articular angle (S-Ar-Go) and Gonial angle (Ar-Go-Gn) were measured. RESULTS: In angular measurements statistically significant differences were found in the saddle and gonial angles between class I, II, and III skeletal pattern. In linear measurements, anterior and posterior cranial base lengths were not significantly different among groups however, ramal height and mandibular body length were significantly different among groups with a P value < 0.05. CONCLUSIONS: Skeletal class III has a larger gonial angle, ramal height and mandibular length. Males have larger linear measurements and females have larger angular measurements.