Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie最新文献

Objective: To investigate quality of life changes, family impacts, and predictors of successful overjet (OJ) reduction in patients treated with removable functional appliances for prominent upper front teeth.

Patients and methods: A total of 86 cases were analyzed, whose ages ranged from 11 to 13 years (median 12; 43% female). They were randomly allocated to treatment by twin block (TB) and Sander bite-jumping appliance (SBJ). OJ was measured before and after 1 year, and the Child Perceptions Questionnaire, Parental-Caregivers Perceptions Questionnaire, and Family Impact Scale were self-administered.

Results: Treatment was unsuccessful in 33% of patients (discontinued regular check-ups or OJ reduction ≤ 40%). In successfully treated individuals, there was a reduction in problems related to child emotional well-being (EW) and oral symptoms, parental EW, and family impacts (p ≤ 0.010). In unsuccessfully treated individuals, there was a reduction in problems related to child EW and social well-being (p ≤ 0.036). In the multiple logistic regression model, sex, type of appliance, and parental perception of the child's functional limitations before treatment were predictors of successful OJ reduction (p < 0.001). Success odds were 8.1 times increased with TB compared to SBJ appliance (95% confidence interval [CI] 2.4-27.6; p = 0.001), 5 times in males (95% CI 1.6-15.5; p = 0.006) and 5 times when parents observed lowered functional limitations (≤ 4) in their child (95% CI 1.5-16.4; p = 0.008).

Conclusion: Appliance type, sex, and parental perceptions of a child's functional limitations predicted treatment success. Both successfully and unsuccessfully treated young adolescents reported improvement in oral health-related quality of life, implying that unsuccessfully treated patients convinced themselves that it was worth being treated.

Purpose: This study assessed the accuracy and repeatability of the orthodontics-related information generated by Chat Generative Pre-trained Transformer (ChatGPT, model GPT-4o, 18 July 2024, OpenAI, San Francisco, CA, USA) and evaluated its usefulness for patient education by comparing artificial intelligence (AI)-generated responses to questions that patients frequently search for with responses from two orthodontic specialists.

Materials and methods: In January and February 2025, 30 descriptive questions (15 on basic orthodontics and 15 on clinically advanced orthodontics) on nondecision, informational content in patient education were assessed, including a "briefly summarize within 500 characters" condition. Accuracy was defined as a response match between ChatGPT and the orthodontist, repeatability was the consistency of ChatGPT output over two iterations. Evaluations used a 5-point Likert scale for accuracy and a 5-point Global Quality Score (GQS) for repeatability. Data were analyzed using R, Wilcoxon signed-rank test and the Mann-Whitney U test.

Results: Repeated responses from ChatGPT showed high repeatability with consistent overall accuracy. For basic orthodontics questions, accuracy increased slightly from 4.27 ± 1.03 to 4.53 ± 0.83 (p = 0.203). For clinically advanced orthodontics questions, accuracy remained stable (first: 3.67 ± 1.05, second: 3.73 ± 0.46, p = 0.850). In terms of repeatability and quality assessed by GQS, basic orthodontic questions scored moderately (first: 3.13 ± 0.83, second: 3.27 ± 0.70, p = 0.580), whereas clinically advanced orthodontics questions received higher GQS scores (first: 4.20 ± 0.77, second: 3.80 ± 0.56, p = 0.095), indicating potential applicability in patient education contexts.

Conclusion: The accuracy and repeatability of ChatGPT's responses varied by question type: basic questions were more accurate, while clinically advanced orthodontic questions resulted in higher repeatability and quality. As these findings are limited to patient education and general information delivery, ChatGPT should not be considered a replacement for professional orthodontic expertise.

Aim: The aim of this retrospective study was to evaluate the accuracy of rotational movements of maxillary and mandibular canines and premolars achieved using clear aligners combined with a segmental lingual appliance, as planned in the digital setup, and to compare these results with those obtained using clear aligners alone.

Materials and methods: This retrospective cohort study included 40 adult patients, analyzing 40 teeth (20 canines and 20 premolars), each presenting at least 15° of rotation. The sample was divided into two groups: a study group treated with F22 aligners (Sweden & Martina, Due Carrare, Padua, Italy) combined with a segmental lingual appliance to correct rotation without attachments and a control group treated with F22 aligners using vestibular attachments to facilitate the rotational movement. Digital models acquired at three stages-pretreatment (T0), ideal posttreatment (T1), and actual posttreatment (T2)-were analyzed using visual aesthetic malocclusion (VAM, Vectra, Canfield Scientific, Fairfield, NJ, USA) software to assess rotation values and calculate imprecision and accuracy for each tooth. Statistical analysis was conducted to compare the two groups.

Results: The study group showed significantly higher accuracy in rotational movements compared to the control group. The mean accuracy was 88.3% for the hybrid approach, versus 55.7% for clear aligners with attachments alone, and this difference was statistically significant (p < 0.01). This improvement was consistent across both canines and premolars, with statistically significant differences in all subgroups.

Conclusion: The combination of clear aligners with a segmental lingual appliance provided superior control in managing severe rotations of rounded teeth, resulting in greater predictability compared with aligners alone.

Purpose: Lateral photographs are routinely evaluated as part of orthodontic diagnostics and treatment planning. Anthropometric measurements based on soft tissue landmarks are taken to evaluate facial features and attractiveness. The detection of these landmarks is a process performed by specialists and prone to intra- and inter-annotator variability. The aims of this investigation were (1) to train an artificial intelligence (AI) algorithm to automatically detect landmarks on lateral photographs, (2) to establish a high-quality gold standard dataset to evaluate landmark detection accuracy, and (3) to compare the performance of AI with that of clinical experts.

Methods: The AI algorithm was trained on a dataset of 991 photographs, with three clinical experts annotating 14 soft tissue landmarks on each photograph. Eleven experts annotated a separate dataset of 56 photographs, to establish the gold standard. Metric scaling of the photographs was achieved by transferring scaling from corresponding lateral cephalograms. Based on the detected landmarks, 11 anthropometric measurements were taken, and the performance of the experts and AI was compared against the gold standard by comparing errors from the ground truth using Mann-Whitney U tests.

Results: At a 2.0 mm threshold, the AI model achieved successful detection rates exceeding 95% for 12 of 14 landmarks. Compared with individual expert annotations, AI predictions showed reduced variability and lower mean radial errors for landmarks with high inter-annotator disagreement. Anthropometric measurements derived from AI predictions demonstrated smaller absolute errors than expert-based measurements.

Conclusion: This study demonstrates that AI-based landmark detection on lateral photographs can achieve accuracy comparable to expert annotations, demonstrating greater consistency for those landmarks exhibiting high inter-annotator variability.

Purpose: Large overjet increases the risk of traumatic dental injury (TDI). This study, part of the Münster Long-Term Study (MLS), aimed to investigate long-term changes in overjet with or without orthodontic treatment and to evaluate whether correcting large overjet can reduce Decayed, Missing, and Filled Teeth Index (DMFT) scores of maxillary incisors.

Methods: Eligible for inclusion in this longitudinal cohort study (MLS) were 667 primary school children who underwent two systematic orthodontic examinations between 1981 and 2001 (T0). Data collection at follow-up in 2022-2023 (T1) included a clinical examination and intraoral scans to evaluate overjet, DMFT, TDI and orthodontic treatment history. Participants were divided into treated and untreated groups. Statistical analysis included Mann-Whitney U tests and paired t‑tests, with significance set at α = 0.05.

Results: A total of 73 participants could be enrolled in the follow-up: 50 treated (female/male: 27/23; mean age 38.3 ± 5.1 years) and 23 untreated (female/male: 10/13; mean age 39.1 ± 6.0 years). The mean observation period was 30.0 ± 5.3 years. At T0, the mean overjet was significantly larger in the treated group than in the untreated group (4.0 ± 1.78 mm vs 2.6 mm ± 0.79, p = 0.002). The treated group showed a significant reduction in overjet from T0 to T1 (p < 0.001), while changes in the untreated group were not significant (p = 0.601). At T1, differences in overjet between groups were no longer significant (p = 0.105) and there was no significant difference in DMFT scores of the maxillary incisors (p = 0.276). TDI of the anterior teeth occurred in 30.0% (n = 15) of the treated group and in 8.7% (n = 2) of the untreated group at T1. Logistic regression analysis showed that each millimeter increase in overjet at T0 was associated with 47% higher odds of TDI (odds ratio 1.47, 95% CI 1.05-2.13).

Conclusion: Orthodontic treatment can effectively improve overjet in the long-term. However, it did not reduce DMFT scores of the maxillary incisors in this MLS sample.

Purpose: This prospective cohort study aimed to evaluate whether salivary leptin hormone levels correlate with skeletal and dental responses to functional therapy in normal-weight versus overweight skeletal class II malocclusion patients.

Methods: Thirty-two patients with skeletal Class II division 1 malocclusion were divided into two groups: overweight and normal weight. All patients were treated with twin block appliances; their growth stage being about MP3cap. Lateral cephalometric x‑rays and body mass index (BMI) percentiles were assessed before (T0) and at the end of the functional treatment (T1). Unstimulated saliva samples were collected from all patients at four time points (before, in the first month, in the third month and at the end of the functional treatment) using a noninvasive passive pouring method. Leptin levels were measured photometrically using an enzyme-linked immunosorbent assay (ELISA) kit.

Results: Overweight patients exhibited higher salivary leptin levels and earlier skeletal maturation. Overjet correction was achieved in these patients with more incisor movement and they showed greater mandibular length increase. Correlation analysis revealed positive associations between leptin and the change of maxillary parameters as well as of soft tissue convexity. Negative correlations were observed between salivary leptin levels and changes in posterior facial height (PFH), PFH/AFH ratio (AFH: anterior facial height), and lower incisor inclination.

Conclusion: Body weight significantly affected treatment timing and outcomes in Class II correction and should be considered in adolescent treatment planning.

Purpose: The aim of this study was to develop an artificial intelligence (AI) model capable of quantifying crowding and spacing in the upper arch and to validate its accuracy by comparing the model's results with those of manual interactive digital space analysis.

Materials and methods: This study included intraoral photographs and occlusal scans of the upper dental arch of orthodontic patients treated at the University of Sharjah (2022-2024). The YOLO (You Only Look Once) 8 Pose Model was generated using a training and validation dataset (832 images). The AI model performed tooth segmentation and tooth point detection on the occlusal images, followed by automated quantification of tooth size-arch length discrepancy (TSALD). Manual space analysis was conducted using OrthoCAD (Cadent, Fairview, NJ, USA) software and the data were compared with the results of the AI model using a testing dataset (300 images). TSALD was categorized based on the index of treatment complexity, outcome, and need (ICON). Qualitative data were presented as frequency and distribution, and comparisons were performed by using Fisher's exact test. Correlation between manual and AI-measured TSALD was evaluated using Pearson's correlation coefficient.

Results: The model achieved an overall accuracy of 90%. The largest discrepancies were found in cases presenting mild crowding (< 2 mm, 7%), severe spacing (5.1-9 mm, 5%), and moderate spacing (2.1-5 mm, 3.3%). A strong correlation (> 0.92) between manual and AI TSALD measurements indicated high reliability and potential interchangeability.

Conclusion: The AI model was successfully developed and validated, achieving 90% accuracy, demonstrating its potential as a reliable tool for quantifying TSALD in orthodontic diagnostics.

Purpose: We aimed to investigate early effects of regulating alpha‑7 nicotinic acetylcholine receptor (α7nAChR) agonists and antagonists on maxillary expansion in mice.

Methods: We allocated 36 six-week-old male C57BL/6J mice into three group: 1) expansion alone, 2) expansion plus the α7nAChR-specific agonist 3‑(2,4-dimethoxybenzylidene)-anabaseine dihydrochloride (GTS-21), and 3) expansion plus alpha-bungarotoxin (α-BTX), a competitive antagonist of α7nAChR. The groups were daily injected with saline, GTS-21 (4 mg/kg/day) or α‑BTX (1 mg/kg/day), respectively, from days 0-7. In addition, a mouse model of maxillary expansion was established. Masson's trichrome staining was used to observe morphological changes and immunohistochemistry was performed to analyze α7nAChR, interleukin (IL)-1β, IL‑6, tumor necrosis factor (TNF)-α, runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN) expression in the midpalatal suture. Microcomputed tomography was used to measure midpalatal suture and palatal basal bone widths. We assessed the normal distribution of our data using the Kolmogorov-Smirnoff test and evaluated the homogeneity of variance by Levene's test, followed by a two-way ANOVA and Bonferroni tests at a significance level of P < 0.05.

Results: In the GTS-21+expansion group, osteogenesis was more active in the middle palatine suture. New bone was calcified and deposited in the suture and we observed decreased IL-1β, IL‑6, and TNF‑α expression (P < 0.05). In the α‑BTX+expansion group, we observed increased proinflammatory cytokine and decreased RUNX2 and OCN expression and increased midpalatal suture and palatal basal bone widths (P < 0.05).

Conclusion: Using α7nAChR agonists and antagonists to regulate the cholinergic anti-inflammatory pathway, the secretion of inflammatory factors and osteoblast markers during maxillary expansion were altered, indicating the potential for clinical modulation of maxillary palatal suture expansion.

Purpose: Adverse side effects of fixed retainers in terms of unwanted tooth movements have been described for both the upper and lower jaw, but data about the extent and movement patterns for the maxilla are scarce. The purpose of the present retrospective case-control study was to analyze the amount and direction of unwanted tooth movements despite upper bonded retainers as well as to analyze possible predisposing pretreatment- and treatment-related factors.

Methods: Plaster casts of 1026 patients who completed orthodontic treatment and a subsequent retention phase of 2 years were screened for unintentional tooth movements. The study group comprised 57 patients with visually obvious tooth movements in the upper jaw, while 57 randomly selected patients without visible tooth movements served as control group. For all patients, plaster casts after debonding of multibracket appliance (T1) and after supervised retention (T2) were digitized, and superimposed digitally using a stable palatal reference area. Thereafter, translational and rotational movements were measured in all three planes of space. Pretreatment- and treatment-related factors of the study and control groups were compared by χ² test, exact Fisher test, Mann-Whitney U test, and the T‑test for independent samples.

Results: The mean translational movements ranged between 0 and 0.6 mm and the average rotational movements between 0 and 1.3°. Large individual movements up to 2.7 mm translation and 15.9° rotation were seen. A movement pattern around the Y‑ and Z‑axis with an opposite rotational peak at the canines ("upper twist effect") was identified. Compared to the control group, patients of the study group showed a significantly smaller intercanine width pretreatment. Also, study group patients presented a larger intercanine expansion and a slightly larger overjet reduction during treatment, and were more often affected by retainer bonding site detachments and wire fractures, but without reaching statistically significance.

Conclusion: Upper bonded retainers show a similar unwanted movement pattern ("twist effect") like the one described for mandibular retainers.

Purpose: The aim of this study was to examine the effect of methylphenidate, prescribed for individuals with attention deficit hyperactivity disorder (ADHD), on orthodontic tooth movement (OTM) and root resorption.

Methods: In all, 30 rats were divided into (1) control (C), (2) constant (MCD), and (3) increasing dose of methylphenidate (MID) groups and 2 subgroups for each of them (nonorthodontic (30 days)/orthodontic (44 days)). After receiving saline or methylphenidate for 30 days, rats in the nonorthodontic groups were euthanized (n = 5/group). Subsequently, 50 g of orthodontic force was applied to the remaining rats' first molars for 14 days (orthodontic groups). Quantitative micro-computed tomography (micro-CT) and immunohistochemical analyses were conducted. For statistical analyses Kruskal-Wallis and Dunnet tests were applied with a significance set at p < 0.05.

Results: Micro-CT analysis demonstrated a statistically significant increase in tooth displacement with higher doses of methylphenidate compared to control and lower-dose groups, though no significant difference was detected between MID-44 and MCD-44 groups. Orthodontic force led to a significant increase in root resorption, peaking in the coronal region and diminishing toward the apex. The highest amount of resorption was observed in the MID groups, with a significant difference between nonorthodontic MID-30 and C‑30 groups. No significant changes in bone parameters were noted in the tension zone, but numerical reductions in trabecular thickness (Tb.Th), bone volume fraction (BV/TV), and bone mineral density (BMD) were observed. In nonorthodontic cohorts, VEGF and RANK levels were significantly elevated in the MID-30 group, along with increased TRAP expression, indicating bone resorption. Orthodontic cohorts exhibited a significant increase in RANK- and TRAP-positive cells with methylphenidate administration. Reductions in OPG and elevations in RANK, RANKL, VEGF, and TRAP were noted, primarily between orthodontic and nonorthodontic groups.

Conclusion: The present rat model suggests a weak potential for methylphenidate to increase root resorption. However, increased doses of methylphenidate accelerated OTM.