This study aimed to screen favorable and unfavorable profile outcomes in orthodontic camouflage treatment of skeletal Class II cases, based on which to identify the reference line and the associated value for the optimal incisor position objective (IPO) in such cases. A total of 140 Chinese adult skeletal Class II cases were included, who finished orthodontic camouflage treatment with anterior retraction following premolars extraction. Post-treatment lateral cephalograms were trimmed and converted into silhouettes, rated by a panel of orthodontists. The top 30% and bottom 30% ranked cases were included as the favorable and unfavorable profile group respectively. The distances of U1 anterior to the GALL line (U1-GALL), point A vertical (U1-Av), and ANS-Pog line (U1-ANPo) were measured as IPO indicators. U1-ANPo in the favorable profile group was 4.74 ± 1.65mm, significantly different from that in the unfavorable profile group (6.02 ± 3.61mm). U1-GALL was -2.68 ± 2.30 mm and -1.12 ± 2.02mm, and U1-Av was 4.49 ± 3.97mm and 6.22 ± 4.42mm, in the favorable and unfavorable profile group respectively, neither showing significant difference. Among three indicators, only U1-ANPo had a significant discriminatory capacity (AUC = 0.74, P = 0.007) for differentiating between the favorable and unfavorable profile group. In skeletal Class II orthodontic camouflage treatment, the relatively favorable post-treatment profiles are associated with the U1 position anterior to the ANS-Pog line. U1-ANPo of around 4.7mm could be tentatively proposed as a practical IPO reference in treatment planning for such cases.

Clear aligners face biomechanical limitations in complex tooth movements, particularly first molar mesialization, despite attachment use. Finite element analysis (FEA) can elucidate optimal attachment designs for force delivery. To compare displacement patterns and stress distribution during maxillary first molar mesialization using four attachment designs via 3D FEA. A maxillary model (MRI-derived) was created with periodontal ligament (PDL), alveolar bone, and clear aligner (0.75mm thickness). Five scenarios were simulated: no attachment (Model-I), vertical rectangular (Model-II), horizontal rectangular (Model-III), optimized double semi-ellipsoidal (Model-IV), and Yin-Yang attachments (Model-V). Mesial displacement (0.5mm) was applied, and deformation/stress were analyzed using ANSYS Workbench. Model-IV (optimized attachment) demonstrated the least first molar tipping, evidenced by its lowest total mesial crown displacement (0.319mm), and provided the best mesiodistal control. Conversely, Model-I (no attachment) exhibited the highest tipping, with a total mesial crown displacement of 0.376mm. Yin-Yang attachments (Model-V) significantly reduced buccal displacement by 92% compared to Model-I. Horizontal rectangular attachments minimized rotational movement. Optimized double semi-ellipsoidal attachments provide superior first molar mesialization control, while Yin-Yang designs enhance buccal-lingual stability. Attachment geometry critically influences aligner efficacy.

BackgroundMaxillary expansion has been a treatment of choice for correcting transverse skeletal discrepancies, especially in growing patients. For older patients, Mini-implant Assisted Rapid Palatal Expansion (MARPE) offers a promising treatment option. This study evaluates the treatment outcomes of Custom 3D-printed MARPE compared to Conventional MARPE (MSE-II).MethodsThis retrospective study analyzed CBCT images from 42 patients aged 16 to 35 years, comparing measurements before (T1) and after (T2) expansion. The conventional (n = 21) and custom (n = 21) MARPE groups were matched with age and sex. Skeletal and dental changes were evaluated measuring twelve distances and four angles using Dolphin Imaging Software (Chatsworth, Calif). The measurements included frontozygomatic and maxillary widths, nasal cavity width, and dentoalveolar inclination. The effectiveness of each appliance was evaluated based on magnitude of expansion and successful correction of transverse discrepancy.ResultsThe custom MARPE group demonstrated comparable or greater increase in width across various anatomical landmarks to the conventional group. Logistic regression suggested a trend toward higher odds of successful transverse discrepancy correction with custom MARPE.ConclusionsCustom 3D-printed MARPE appliances may offer advantages in achieving skeletal expansion in older patients. Individualized appliance design and strategic mini-implant placement could contribute to effective treatment. However, further research is needed to evaluate long-term outcomes, cost-effectiveness, and potential complications to better guide appliance selection for each patient.

BackgroundThe aims of this study were to gather expert agreement about essential aspects of clear aligner therapy (CAT) and to determine what research areas need further investigation.Materials and methodsA steering committee performed literature selection and compiled a list of 25 statements. This study used a modified Delphi method involving a panel of 23 international orthodontic experts. Six essential areas of CAT were investigated: treatment efficacy, quality of life, side effects, management of growing patients, treatment with extraction, and treatment of periodontal patients. A panel of experts assessed 25 statements using a 5-point Likert scale throughout 3 rounds of the study. A steering committee adjusted statements that failed to achieve consensus through either revision, splitting, merging, or complete removal.ResultsAfter the third round, 22 statements achieved consensus while 3 statements were rejected. The panel agreed that aligners could be used effectively in some types of malocclusions, such as those with mild or moderate crowding or open bite cases. The experts reached a consensus on the biomechanical limits of clear aligners. However, they agreed on the benefits in terms of improved quality of life during treatment and easier maintenance of oral hygiene maneuvers. Regarding specific patient categories, the panelists supported the use of aligners in periodontal patients with tooth migration requiring tipping movements. They also agreed on the advantages of using a rapid palatal expander over aligners in growing patients.ConclusionsThe panel members reached agreement on most topics. However, they acknowledged limitations in the current literature regarding root resorption and orthodontic relapse with CAT compared to fixed appliances. The absence of agreement on treatment duration, effects on skeletal growth, and the management of periodontally compromised patients highlights significant evidence gaps that warrant further research.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40510-025-00575-1.

There is a lack of studies on patient-reported outcomes in orthodontics. The aim of this study was to evaluate the changes in patient-reported chief complaints during orthognathic surgery treatment. Patients undergoing orthognathic surgery at the University Hospital Münster between 2019 and 2023 were eligible for inclusion in this prospective cohort study. Patient-reported chief complaints were recorded on visual analogue scale (VAS) forms before treatment ([Formula: see text]), and reevaluated after presurgical orthodontic treatment ([Formula: see text]), and 6-9 months after surgery ([Formula: see text]). Chief complaints were grouped into three main categories (pain, function, aesthetics) and ten subcategories, and their intensity was quantified over time. A total of 217 out of 386 recruited patients (56%) completed all study assessments and were included in the final analysis (female/male = 126/91, median age 24.1 years). Dental function, facial aesthetics, and dental aesthetics were the most frequently reported complaints at [Formula: see text]. At [Formula: see text], there was a statistically significant improvement in dental aesthetics. There was a statistically significant reduction in the intensity of each of the 10 subcategories from [Formula: see text] to [Formula: see text]. Orthognathic surgery patients most frequently report dental function, facial aesthetics, and dental aesthetics as their chief complaints, and these complaints were improved significantly after treatment. The improvement in patient-reported chief complaints can be used to inform patients prior to treatment.

The angulation of third molars is a critical factor influencing the likelihood of impaction. Orthodontic premolar extractions have been hypothesized to affect the eruption path of developing third molars by modifying available space and mesial drift patterns. This systematic review and meta-analysis aimed to assess whether premolar extraction during orthodontic treatment alters the angulation of developing third molars compared to non-extraction protocols. Observational studies comparing angular measurements of third molars between extraction and non-extraction orthodontic treatments were included. Studies without a control group or adequate cephalometric data were excluded. A comprehensive literature search was conducted across two electronic databases (MEDLINE, Scopus) up to November 2024, following PRISMA 2020 guidelines. Risk of bias was evaluated independently by two reviewers using the ROBINS-I tool. A random-effects meta-analysis was conducted, and the certainty of the evidence was assessed using the GRADE approach. Nine studies (865 participants) were included. For mandibular third molars, extraction was significantly associated with improved angulation (SMD = - 0.37; 95% CI: - 0.59 to - 0.15; p = 0.004). Significant differences were found in M3L/M2L (MD = - 1.31; 95% CI: - 1.76 to - 0.85; p = 0.003) and M3L/PP (MD = - 4.85; 95% CI: - 8.50 to - 1.21; p = 0.02). No statistically significant difference was observed in the M3L/MP angle. In the maxilla, only the M3U-PP angle showed a significant change (MD = - 5.79; 95% CI: - 11.53 to - 0.04; p = 0.049). Meta-regression revealed no association with age, sex, or premolar type. Certainty of evidence ranged from low to moderate.