ObjectiveTo study craniofacial growth and hypodontia in individuals born with Van der Woude syndrome (VWS) and compare with matched controls with and without a cleft.DesignA multicenter retrospective case-control study.SettingIndividuals from three craniofacial centers in Sweden and from a historical archive of Swedish healthy children were included.PatientsSixty individuals, with VWS (n = 20), non-syndromic cleft lip and/or palate (NSCL/P) (n = 20), and healthy controls (CTR) (n = 20), matched for age, gender and cleft type.InterventionsTwo lateral cephalograms per individual, taken at 10 and 16 years of age, were analyzed. Orthopantomograms were used to evaluate hypodontia.Main Outcome MeasuresCraniofacial growth followed longitudinally, with the primary variables SNA, SNB, ANB, NL/ML, and maxillary length. Prevalence of hypodontia was also recorded.ResultsMaxillary length increased 0.3 mm in the VWS group during puberty, compared to 4 mm in the NSCL/P group and 5.5 mm in the CTR group. Both cleft groups had a retruded maxilla at 16 years of age. The change in vertical jaw relation from 10 to 16 years showed a statistically significant difference between the VWS and the CTR group, with a slightly more posteriorly inclined mandible in the VWS group at 16 years. A statistically significant difference in hypodontia is seen between the cleft groups. In the VWS group, 90% had hypodontia compared to 60% in the NSCL/P group.ConclusionIndividuals born with VWS have reduced maxillary growth during puberty and a higher prevalence of hypodontia compared to matched controls in the studied population.

BackgroundThis study aimed to develop an integrated artificial intelligence (AI) pipeline for cervical vertebral maturation (CVM) staging and skeletal jaw relationships and to validate its output against the results of human observers.MethodsA total of 720 lateral cephalograms were collected from the archives of the orthodontic department. The participants’ ages ranged from 8 to 18 years. Cephalograms were categorized into six cervical stages based on McNamara’s criteria and classified into skeletal Class I, II, and III patterns based on their ANB angles. The dataset was divided into a training set (n = 540) and a test set (n = 180). The training set was used to train a convolutional neural network (CNN) and a YOLOv8 model. The test set of cephalograms was coded and randomly assigned to two orthodontists for comparison with the AI model results using weighted kappa and Cohen’s kappa statistical analyses to verify accuracy.ResultsFor human observers, the interobserver agreement ranges were as follows: (κw ≈ 0.976–0.989) for skeletal classification and (κw ≈ 0.956–0.999) for CVM staging, while the intra-observer reliability was also almost perfect for both methods (κw ≈ 0.82– 0.85). Substantial agreement was found between the generated AI model and human observers for skeletal classification (κ = 0.725) and CVM staging (κ = 0.786). Both results were statistically significant (p < 0.01).ConclusionsWithin the limitations of this study, the AI model exhibited substantial agreement with human observers for CVM staging and skeletal assessment, demonstrating its potential viability as a clinical decision-support tool.

Tongue function significantly influences craniofacial development, yet the morpho-functional characteristics of the tongue across different sagittal skeletal patterns remain unclear. This study aimed to quantitatively evaluate tongue muscle strength and resting posture in adolescents, delineate their biomechanical pathways, and construct data-driven diagnostic models for sagittal skeletal patterns. A cross-sectional study was conducted on 182 adolescents (11-17 years) stratified into Class I, II, and III sagittal patterns based on the ANB angle. Maximum active tongue pressure (MTP) was measured using a digital dynamometer. Resting posture, including the Tongue Tip Index (TTI), Tongue Tip Distance (TTD), and Tongue Dorsum Distance (TDD), was evaluated using lateral cephalograms. Data were analyzed using multivariable linear regression analysis, mediation analysis, and a Chi-squared Automatic Interaction Detection (CHAID) algorithm. The Class III cohort exhibited significantly reduced MTP (median: 1.65kg) compared to Class I and II subjects (~ 2.20kg; P < 0.001). Mediation analysis identified a partial mediation relationship: while MTP demonstrated a significant direct statistical association with the ANB angle, 32.4% of the total association was indirectly mediated through TTI. The CHAID model identified reduced MTP (≤ 1.85kg) as the primary root node associated with Class III risk. TTI (≤ 2.57%) served as a critical secondary stratifier of Class III risk. In adolescents, skeletal Class III malocclusion is associated with reduced tongue pressure and a lowered resting posture. Tongue muscle force demonstrates both a direct statistical association with the sagittal skeletal base and an indirect association mediated by the maintenance of an appropriate tongue tip position. The diagnostic model highlights reduced MTP as the primary risk indicator for Class III patterns, which is further stratified by TTI.

PurposeTraditional craniofacial phenotyping of obstructive sleep apnea (OSA) relies on predefined anatomical hypotheses, often yielding incomplete assessments. This study aimed to apply multiple explainable deep learning (DL) approaches to explore novel craniofacial phenotypes.Patients and MethodsA multimodal DL model was trained using frontal and lateral facial images, lateral cephalograms, and demographic data from 130 participants (65 OSA patients diagnosed by overnight polysomnography, and 65 age- and sex-matched controls). Explainability analysis of the model’s prediction was conducted in a subset of 56 participants per group using average face analysis, feature importance analysis, and gradient-weighted class activation mapping (Grad-CAM). Targeted measurements were then performed on the identified non-traditional regions to validate morphological differences.ResultsThe model achieved an area under the curve of 0.87. The explainability analysis identified not only anatomical structures that have been confirmed to predict OSA (such as the mandible, chin, and hyoid regions), but also the middle and upper facial third (e.g. the forehead, eyebrows, and upper eyelids), which has not been fully emphasized in previous studies. Targeted measurements confirmed a significantly smaller inter-eyebrow distance, increased frontal protrusion (p < 0.001) and frontal sinus area (p < 0.001) in OSA patients.ConclusionExplainable DL expanded OSA-related craniofacial phenotypes. Future studies are needed to validate these upper-face traits in larger cohorts and clarify their relevance to OSA subtyping and mechanisms.

Few studies have demonstrated the reliability of biodegradable osteosynthesis systems in orthognathic surgery; however, studies on the use of biodegradable osteosynthesis systems after mandibular osteotomy, including sagittal split ramus osteotomy (SSRO), are limited. This pilot study aimed to compare the safety and skeletal stability after segmental fixation using curved titanium and box-type biodegradable systems in SSRO for mandibular prognathism. Patients who underwent SSRO for correction of mandibular protrusion with malocclusion between September 2024 and March 2025 were included. After conventional SSRO, the bilateral segments were fixed using curved 6-hole titanium plates (Ti group) or 6-hole box-type biodegradable plates (Bi group). Lateral and frontal cephalograms and computed tomography images were obtained before (T0), 5±2 days after (T1), and 6±1 months after surgery (T2). In the Ti group, although the absolute change in the ramus plane and gonial angles from T1 to T2 was -2.3±5.1 and 3.6±7.4 degrees, respectively, no significant change was observed in any of the measured angles. In contrast, in the Bi group, significant changes from T1 to T2 were observed in the mandibular plane (4.8±2.3 degrees), ramus plane (-5.7±4.0 degrees), and gonial angles (8.8±4.2 degrees). The changes in the vertical and horizontal positions of point B, menton and pogonion were not significantly different between the 2 groups. The results of this pilot study with a small sample size suggested that in patients undergoing SSRO, bone segmental fixation using 6-hole box-type biodegradable plates may provide acceptable short-term skeletal stability and safety. Since definitive comparisons require larger prospective studies, further prospective studies with larger sample sizes are warranted.

While malocclusion prevalence and orthodontic treatment need have been widely described, the association between objectively quantified craniofacial morphology and actual orthodontic treatment initiation remains insufficiently characterised. This study aimed to identify cephalometric parameters associated with orthodontic treatment initiation in routine clinical practice. A retrospective observational study was conducted using clinical records from a private orthodontic centre in Poland. Consecutive patients aged ≥ 11 years who attended an initial orthodontic consultation between 2022 and 2024 and had a lateral cephalogram were included (n = 902). Orthodontic treatment initiation at the study centre was defined as a binary outcome (yes/no). Cephalometric variables derived from Segner-Hasund analysis were assessed, including sagittal and vertical skeletal parameters, dentoalveolar measurements, and soft-tissue indices. Comparisons between treated and untreated individuals were performed using non-parametric tests, with additional analyses stratified by gender and age. Also, the univariate and multivariable logistic regression modelling was conducted. Of the 902 participants, 490 initiated orthodontic treatment and 412 did not. No significant differences were observed for sagittal skeletal parameters (SNA, SNB, ANB, Wits appraisal) or skeletal class distribution between groups. In contrast, significant differences were identified for vertical skeletal configuration (NSL-NL), maxillary incisor protrusion relative to NA (1+:NA, mm), and the lower facial height index. Gender-stratified analysis revealed that treatment initiation in females was associated primarily with maxillary incisor inclination and protrusion, whereas in males it was associated with vertical skeletal parameters and lower facial height. Age-stratified analyses indicated that vertical skeletal characteristics were more strongly associated with treatment initiation in adult and older individuals, while no clear cephalometric differentiators were identified in younger patients. In logistic regression analysis, increased NSL-NL angle was independently associated with a lower likelihood of undertaking orthodontic treatment, while greater upper incisor protrusion (1+:NA, mm) increased the probability of treatment initiation. Although several associations reached statistical significance, the majority of cephalometric variables showed no significant relationship with treatment initiation, and effect sizes for statistically significant predictors were small, with the largest odds ratio observed for 1+:NA (mm) (OR = 1.053). In the multivariable model, NSL-NL and SNA remained significant predictors, and the model demonstrated good fit. Associations between cephalometric parameters and orthodontic treatment initiation were selective and predominantly related to vertical skeletal configuration and maxillary incisor position. These findings suggest that cephalometric morphology alone has limited explanatory value for treatment uptake and should be interpreted within a broader multifactorial framework encompassing aesthetic perception, patient preferences, and contextual factors.

This study aims to apply a CBCT-based method to assess upper airway obstruction severity and evaluate its association with craniofacial development and orthodontic treatment outcomes in children. A cross-sectional cohort of children aged 6 to 12 years was analyzed. Lateral cephalograms and CBCT images were obtained. Tonsillar and adenoid size, as well as craniofacial variables, were measured on cephalograms, while nasopharyngeal and oropharyngeal airway dimensions were assessed on CBCT using Dolphin software. Airway obstruction severity was classified, and group differences were analyzed using t tests and ANOVA (P<0.05). Compared with degree I, degree II obstruction showed greater decreases in saddle angle (4.08 degrees±3.85 degrees versus -1.18 degrees±4.30 degrees, P<0.05) and gonial angle (1.44 degrees±2.38 degrees versus -2.09 degrees±2.81 degrees, P<0.05), and a greater increase in articular angle (-6.10 degrees±5.28 degrees versus 0.67 degrees±5.42 degrees, P<0.05). Children undergoing adenotonsillectomy combined with orthodontic treatment demonstrated greater increase in SNB (2.63 degrees±1.30 degrees versus 0.80 degrees±1.47 degrees, P<0.05) and a larger reduction in saddle angle (-6.98 degrees±2.29 degrees versus -0.15 degrees±3.42 degrees, P<0.05) than those receiving orthodontic treatment alone. Upper airway obstruction severity was associated with altered craniofacial development in children. Adenotonsillectomy combined with orthodontic treatment was associated with improved mandibular advancement. These findings highlight the importance of airway evaluation in treatment planning.

Adenotonsillar hypertrophy (ATH) is a major cause of upper airway obstruction and is associated with specific craniofacial characteristics. However, the craniofacial morphology of children with ATH is controversial. This study aimed to clarify these discrepancies by investigating the association between the adenoid-to-tonsil (A/T) size ratio and craniofacial characteristics in children with ATH, and examining whether age modifies these associations. Children aged 6-10 years were recruited and classified into ATH or no hypertrophy (NH) groups based on lateral cephalograms. For children with ATH, the relative size of the adenoids and tonsils was quantified using the A/T length ratio measured on lateral cephalograms. Based on the median A/T ratio, the ATH group was further divided into two equal-sized groups: a tonsil-dominant (TD) and an adenoid-dominant (AD) group. Craniofacial differences between groups were evaluated. In addition, associations between the A/T ratio and craniofacial morphology were assessed in the ATH cohort. We further examined whether age (6-8 vs. 8-10 years) acted as a moderator of these associations using interaction analyses. A total of 563 children (207 AD, 207 TD, and 149 NH) were included. TD group exhibited greater SNB (B = 0.65, p = 0.028) and Go-Me (B = 0.69, p = 0.038), along with smaller Ar-Go-Me (B = -0.98, p = 0.029) and Wits (B = -0.68, p = 0.026) than AD group. In addition, the A/T ratio was positively associated with SGn/FH (B = 0.74, p = 0.048). Moreover, interactions between age and the A/T ratio were observed for MP-SN (B = 2.45, p = 0.044) and Ar-Go-Me (B = 2.86, p = 0.045), and Go-Me (B = -2.12, p = 0.013). The relative size of the adenoids and tonsils may be associated with craniofacial morphology in children with ATH, with lower A/T ratios tending to be associated with mandibular protrusion and overgrowth, whereas higher ratios appearing to be associated with clockwise mandibular rotation. Notably, age may modify these associations, suggesting the potential importance of timely airway evaluation and management in orthodontic practice.

Objective(s)To compare the efficacy of sliding mechanics on a 0.020-inch round posterior segment incorporated into a bi-dimensional archwire (BA) versus conventional rectangular-section archwire (CONV) for maxillary canine retraction, rotation, angulation, anchorage loss, overbite change, and external apical root resorption (EARR).DesignRandomized, parallel-group, two-arm clinical trial with 1:1 allocation.SettingDepartment of Orthodontics, University of Damascus; recruitment and treatment July–December 2023.Participants and interventionsPatients aged 18–25 years with mild–moderate skeletal Class II (ANB + 5° to + 7°) and 5–10 mm overjet scheduled for camouflage treatment with extraction of maxillary first premolars were randomized (N = 38) to: (a) BA—bi-dimensional archwire (0.021 × 0.025″ rectangular in the incisor segment; 0.020″ round in canine/premolar/molar slots) or (b) CONV—conventional rectangular-section retraction mechanics.Main outcome measure(s)Primary outcome was monthly maxillary canine retraction rate measured on digitally scanned casts (3D analysis). Secondary outcomes included canine rotation rate, canine angulation change (lateral cephalograms), anchorage loss, overbite change, and EARR (panoramic radiographs).Sequence generationComputer-generated variable block randomization (block sizes 4 and 6) produced by an independent statistician.Allocation concealmentSequentially numbered, opaque, sealed envelopes prepared and stored by the independent statistician; opened after eligibility and baseline assessment.BlindingParticipants and treating clinicians were unblinded; outcome assessors and the study statistician were blinded. Radiographs and digital models were anonymized and allocation was held independently until primary analyses were locked.ResultsThirty-eight participants (19 per arm) completed the study. Observed median retraction rates (T0→TF; T0 = baseline, TF = end of retraction) were BA 1.17 mm/month (IQR 0.20; bootstrap 95% CI 1.08–1.24) versus CONV 0.82 mm/month (IQR 0.13; bootstrap 95% CI 0.76–0.90). Linear mixed-effects modelling adjusted for baseline overjet showed a significant group effect favoring BA (p < 0.001). BA reduced total canine angulation change by 2.90° (95% CI − 4.97 to − 0.82; p = 0.007). Secondary outcomes (rotation, anchorage loss, overbite, EARR) showed only small differences or non-significant trends after Bonferroni adjustment.ConclusionsIncorporating a 0.020″ round posterior segment within a bi-dimensional archwire accelerated canine retraction (~ 43% relative increase) and improved mesiodistal angulation control compared with conventional rectangular mechanics, without clear clinically meaningful increases in rotation, anchorage loss, overbite change, or root resorption. Findings warrant confirmation in larger, multicenter trials with extended 3D imaging follow-up.FundingUniversity of Damascus (Reference no.: 501100020595).Trial registration ClinicalTrials.gov NCT07243509 (retrospectively registered 24 November 2025).Supplementary InformationThe online version contains supplementary material available at 10.1186/s40510-026-00629-y.

To analyse and compare the craniofacial characteristics of patients with nonsyndromic, surgically repaired, complete unilateral cleft lip and palate, aged 8-14 years, treated at 10 cleft care centres. Lateral cephalograms of 396 patients (mean age 11.2 ± 1.6 years; male: female ratio 1:0.64) with unilateral cleft lip and palate from 10 comprehensive cleft care centres across India were evaluated using NemoStudio cephalometric software. Cephalograms were anonymised, coded and digitised for unbiased assessment. Two orthodontists independently traced all radiographs at different time intervals. Eleven hard-tissue and seven soft-tissue cephalometric variables were measured on each radiograph. Inter-rater reliability was assessed using the intraclass correlation coefficient (ICC). Cephalometric analysis demonstrated statistically significant intercentre differences for sagittal skeletal and soft-tissue parameters, including SNA, SNB, ANB, ANS-Me/N-Me, NAPog, nasolabial angle, N'A'Pog' and A'N'B'. In contrast, other parameters did not differ significantly among centres. Dental inclination variables Ui-PP and Li-MP also showed no significant differences. Inter-rater reliability was moderate to good, with ICC values of 0.51-0.85. Considerable intercentre variation was observed in sagittal hard- and soft-tissue craniofacial parameters among children with repaired unilateral cleft lip and palate. However, these variations cannot be attributed to any single component of the treatment protocol. Instead, it reflects the multifactorial nature of cleft care, including variations in surgical timing, technique, presurgical orthopaedics and patient-related factors.

The aim of this study was to compare the response capabilities of generative pre-trained transformers (GPTs) for identical lateral cephalograms (LCs) based on text- and image-based prompts, using the newly developed Artificial Intelligence Based Diagnosis and Treatment Planning Index (AIDTI). A total of 90 LCs from 30 cases each with skeletal Class I, II, and III malocclusions were included. The LCs were presented to GPT-4o, GPT-o3 pro, GPT-5, and GPT-5 pro in two different formats: text-based (numerical data including cephalometric analysis measurements) and image-based (direct image upload) prompts. The responses of the GPTs were evaluated using the newly developed AIDTI, scored on a 0-10 scale and consisting of five criteria: diagnostic accuracy, capability for differential diagnosis, clinical appropriateness of the proposed treatment plan, disclosure of risks and complications associated with the treatment plan, and ability to offer alternative treatment options. Higher performance was observed in text-based prompts, with the highest score achieved by GPT-5 pro (9.62 ± 1.13). By contrast, the performance of all GPTs on image-based prompts was notably lower, with the highest score being 4.16 ± 4.12 for GPT-o3 pro. Additionally, all models showed a tendency to randomly categorize malocclusions as Class II, suggesting systematic bias in their predictions. AIDTI provides a structured and multidimensional framework for the concise, balanced, and clinically meaningful interpretation of GPT performance. Because GPTs are unable to directly analyze LCs, their use as independent or reliable supportive tools in orthodontics remains limited at this stage. GPTs may contribute more reliably to orthodontic practice only when orthodontists prompt the model with text-based cephalometric measurement data. Not applicable.

To assess salivary insulin-like growth factor-1 (IGF-1) and bone alkaline phosphatase (BALP) levels during mandibular advancement with Twin Block appliance. The study enrolled 49 participants with skeletal Class 2 malocclusion, a retrognathic mandible, positive visual treatment objective (VTO), horizontal to average growth pattern and cervical vertebrae maturation index stages 3-4 (CVMI). Participants were treated with Twin Block appliance (Twin Block group [TBG]; n = 39). Salivary samples were collected before treatment (T0), at 7-10 days (T1), 6-10 weeks (T2), 8-10 months (T3) and after treatment (T4). Non-compliant participants formed the non-compliant group (NCG; n = 10). Lateral cephalograms were obtained for cephalometric evaluation. Statistical analyses compared salivary IGF-1 and BALP levels and cephalometric parameters within and between groups. The final sample included 39 participants in the TBG (17 boys, 22 girls; mean age =12.56 ± 1.09 years) and 10 participants in the NCG (5 boys, 5 girls; mean age =12.7 ± 1.16 years). A significant difference was observed in the salivary IGF-1 and BALP levels within the TBG across different time intervals. In the TBG, IGF-1 increased significantly at T1, and BALP significantly increased at T2 and T3. The NCG showed no significant changes in levels of IGF and BALP. A significant positive correlation between IGF-1 and BALP was noted at T1 in the TBG (P <0.05), whereas a significant negative correlation was observed at T2 and T3 (P <0.05). Mann-Whitney test showed a significant increase in mandibular length in TBG compared to NCG. Cephalometric analysis revealed significant improvements in mandibular length in TBG compared to NCG between T0 and T4. The study demonstrated a significant increase in salivary IGF-1 levels within 7-10 days, with BALP levels peaking at 6-10 weeks. These findings suggest a potential role of IGF-1 and BALP in the biochemical response to Twin Block appliance therapy.

Long-term effect of anterior maxillary distraction using the VINK appliance - Retropalatal and Retroglossal airway change.

To analyse the effect of maxillary advancement on speech in patients born with unilateral or bilateral cleft lip and palate (uCLP/bCLP). Using the retrospective cohort study design, the investigators included children with uCLP or bCLP who underwent Le Fort I osteotomy for maxillary advancement between January 2013 and December 2023 at a Swiss university hospital. Predictor variables were cleft type (uCLP/bCLP) and amount of maxillary advancement measured on lateral cephalograms. The primary outcome was speech competency evaluated by two speech therapists using the Borel-Maisonny classification (A: velopharyngeal competence/excellent speech; B: borderline competence/good speech; C: incompetence/poor speech). Appropriate statistical analyses were performed, and P < 0.05 was considered statistically significant. Forty-three non-syndromic CLP patients (mean age 16.4 ± 1.5 years; 37 % female) were included. The mean maxillary advancement was 6.6 ± 2.3 mm. Of the 36 patients classified as A or B preoperatively, 34 showed no change, while two (5.6 %) deteriorated from A to B. All seven patients with preoperative category C remained unchanged. Neither cleft type nor the extent of maxillary advancement significantly influenced postoperative speech (p = 0.65 and p = 0.80, respectively). Although limited by sample size, this study suggests that speech deterioration after maxillary advancement in CLP patients with preoperative category A or B is uncommon. Conversely, Le Fort I osteotomy does not appear to improve speech in patients with preoperative category C.

Vertical facial discrepancies in Brazilian children and adolescents are associated with polymorphisms in members of the Wnt gene family.

Prediction of facial profiles following orthodontic treatment in adult Class III patients using deep neural networks with feature fusion.

This study tested whether conventional 2D incisor mandibular plane angle (IMPA) can be used interchangeably with a rigorously defined 3D one. This single-centre retrospective study included 169 CBCT scans. Synthetic lateral cephalograms were generated from DICOM data to calculate the conventional 2D IMPA between the Go-Me mandibular plane and the lower central incisor long axis. The 3D IMPA used the axes of teeth 3.1 and 4.1 projected three-dimensionally to the orthogonal plane to GoL-GoR-Me and the higher angle was selected. Normality of paired differences was assessed using the Shapiro-Wilk test. Systematic bias was evaluated with a paired t-test. Association between 2D and 3D IMPA was assessed using Pearson's correlation and linear regression. Agreement was quantified by Bland-Altman analysis. Classification agreement within the 85-95° range was evaluated using Cohen's kappa and McNemar's test. Mean 2D and 3D IMPA were 95.29±8.98° and 95.75±9.42°, respectively, with a mean paired 3D-2D difference of 0.46° (paired t-test, P=0.084). Correlation was strong (r=0.931), and linear regression yielded R2=0.867. Bland-Altman bias was 0.46° (95%LoA -6.29° to +7.21°). Classification agreement across the 85-95° range was 83.43% (κ=0.636; McNemar P=0.345). 2D and 3D IMPA showed negligible mean bias, excellent association, and substantial diagnostic concordance. Routine cases may rely on 2D IMPA without material loss of information, whereas in torque-critical, anatomically constrained, or borderline cases the observed ±7° dispersion argues for 3D assessment.

Periodontal changes in patients with skeletal Class III malocclusion with and without prophylactic gingival grafting during presurgical orthodontic treatment.

The objective was to compare the skeletal, dentoalveolar, and soft tissue effects of early Class II light elastics and PowerScope appliance used with self-ligating brackets in Class II Division 2 patients. Thirty-one Class II Division 2 patients were divided into two groups. Group 1 (N = 16, mean age:15.06 ± 1.77 years) was treated with the Damon 3MX self-ligating system and early Class II light elastics. Group 2 (N = 15, mean age:15.87 ± 1.30 years) received Empower self-ligating brackets combined with PowerScope fixed functional appliance (FFA). Lateral cephalograms were taken before treatment (T0) and after achieving a Class I molar relationship (T1). Surveys assessing comfort and pain were analyzed at the beginning and after six months. Group 2 exhibited a significantly greater change in SNB° compared to Group 1, while increases in vertical skeletal measurements were greater in Group 1 (p < 0.05). Both groups exhibited maxillary and mandibular incisor protrusion with no significant difference. Lower molar extrusion (L6-H) was greater in Group 1 (2.77 ± 2.87 vs1.14 ± 1.77mm, p = 0.038), whereas only Group 2 showed significant lower incisor intrusion (p = 0.002). Patients in the early elastic group generally reported better experiences with comfort-related situations. Pain levels at the 4th and 24th hours were significantly higher in Group 2 (p < 0.05). Early light elastics and FFA were effective in normalizing Class II division 2 and corrected the molar relationship at the same time. Both treatment modalities demonstrated comparable dentoalveolar effects, except for the extrusion of lower molars and the intrusion of lower incisors. Patient comfort was better in the elastic group than in the FFA group.

This study aimed to examine three-dimensional (3D) changes in perioral soft tissue after nonsurgical orthodontic treatment of Class III patients using a 3D structured light scanner. The study included 32 Korean patients with skeletal Class III malocclusion who underwent nonsurgical orthodontic treatment with temporary skeletal anchorage devices(TSADs). Two-dimensional lateral cephalograms and 3D facial scans were taken before treatment and immediately after debonding. Seven hard-tissue landmarks were identified in the cephalometric images, and 29 perioral soft-tissue landmarks were identified in the 3D facial images. Changes in the 3D coordinates of these landmarks (x, y, z) were assessed by superimposing post-treatment images onto pre-treatment images. After treatment, the maxillary central incisor tips moved significantly forward (1.43 mm), while the mandibular central incisors moved backward (-2.61 mm). Upper lip landmarks (1) moved forward significantly, while lower lip landmarks (8, 9, 13, 14, 8', 9', LLP) moved backward significantly. There was also significant downward and backward movement at Pg' and Gn'. Orthodontic treatment resulted in maxillary incisor proclination and lingual uprighting of the mandibular incisors, with downward and backward movement of Pg' and Gn'. No significant soft tissue changes occurred in the transverse axis. The upper lip moved forward, while the lower lip and chin (Pg', Gn') shifted backward and downward. The subnasale and the area under the nostrils remained relatively stable, while the lip angle moved posteriorly.