The Angle orthodontist最新文献

Objectives: To compare the profile attractiveness of skeletal Class III patients treated with either a surgery-first approach (SFA) or a conventional surgery approach (CSA), as perceived by surgeons, orthodontists, and laypersons.

Materials and methods: Thirty-four patients were assigned to either the SFA or CSA group retrospectively based on the surgical protocol performed and were evaluated by three distinct groups: oral and maxillofacial surgeons, orthodontists, and laypersons (n = 23 per group). Profile images before (T1) and after orthodontic-surgical treatment (T2) were analyzed using a 5-point Likert scale. Then participants answered the following question: "Which surgical technique was used, CSA or SFA?" Statistical analyses including the Spearman correlation coefficient, the Friedman test, the κ test, independent t-tests, and one-way analysis of variance were conducted to assess correlations and comparisons among evaluator groups (P < .05).

Results: A high and positive correlation (r = 0.86, P < .001) was demonstrated for scores between surgeons and orthodontists, and a low correlation was demonstrated between laypeople and specialists (r = 0.55, P = .01 and r = 0.48, P = .03). No statistically significant relationships were found between esthetic perceptions and the surgical approach regardless of the level of expertise of the evaluators, and it was also not possible to differentiate between the surgical approaches used.

Conclusions: In this study, we indicate that the choice of orthognathic surgical protocol, whether surgery-first or conventional, did not significantly influence the perceived facial profile attractiveness of skeletal Class III patients. These findings support the clinical viability of the SFA protocol, particularly in cases where treatment time or patient preference are factors in decision-making.

Objectives: To develop and validate a standardized protocol for clear aligner (CA) thickness measurement using a three-dimensional (3D)-printed auxiliary device to improve measurement reliability.

Materials and methods: 24 pairs of digital dental models (D0s) were included and 3D-printed into physical models (P0s), from which CAs were thermoformed using 0.75-mm polymer sheets. Measurement auxiliary devices (MADs) were designed on D0s through measurement point selection, direction determination, electronic gauge mapping, and base shaping, and then 3D-printed. Two operators measured CA thickness (40 points per CA, 48 CAs) using an electronic gauge both directly (direct measurement, D-M) and with MADs (auxiliary measurement, A-M) across three sessions. Measurement precision (repeatability and reproducibility) of D-M and A-M were analyzed using intraclass correlation coefficients (ICCs) and repeated-measures analysis of variance (ANOVA) or Friedman tests. Bland-Altman plots were used to evaluate intersession agreement.

Results: A-M demonstrated superior intersession repeatability with ICC > 0.90 at all points and high intersession agreement with a narrow 95% limit of agreement (LoA) and minimal outliers. Interoperator reproducibility for A-M was also higher, with ICCs above 0.75 at all points, compared to D-M, which showed ICCs below 0.75 at almost all points.

Conclusions: The 3D-printed auxiliary device-based protocol provides a precise and operator-independent method for CA thickness measurement, offering a tool for quality control and providing a foundation for future research on material advancement and design optimization to improve aligner functionality.

Objectives: To compare the effect of postsurgical orthodontic treatment between using clear aligners (CA) or fixed appliances (FA) on the postsurgical stability of patients with mandibular prognathism in the surgery-first approach (SFA).

Materials and methods: This retrospective study included 54 patients with mandibular prognathism who underwent surgical orthodontic treatment with isolated mandibular setback surgery. The patients were divided into two groups according to the mechanics of postsurgical orthodontic treatment: the CA group included 27 patients treated with clear aligners, and the FA group included 27 patients treated with brackets during postoperative orthodontic treatment. Cone beam computed tomography scans were taken before, immediately after, and at 3, 6, and 12 months postsurgery to assess mandibular relapse. The measurements of postsurgical mandibular relapse including horizontal and vertical positions were compared according to the treatment progress and groups.

Results: Total postsurgical mandibular relapse at pogonion was 3.2 mm in the CA group and 2.2 mm in the FA group. Relapse was higher at 3 months postsurgery in both groups, with an average forward movement of 1.4 mm in the CA group and 1.7 mm in the FA group. Relapse in the CA group showed no significant changes over time, indicating persistence beyond the initial period. In contrast, the FA group showed a significant reduction in relapse by 3 months. Overall, the CA group tended to have greater and more persistent relapse than the FA group.

Conclusions: Careful consideration of skeletal relapse is needed in the postsurgical management of patients treated with clear aligners in SFA treatment.

Objective: To evaluate the effects of orthodontic traction of impacted maxillary canines on treatment duration, alveolar bone levels, white spot lesions (WSLs), root resorption, and the need for auxiliary appliances.

Materials and methods: In this retrospective study, 116 patients were divided into two groups: 58 with unilaterally impacted maxillary canines and 58 controls without impaction. All patients received nonextraction treatment using labial fixed appliances. Pretreatment and posttreatment panoramic radiographs, intraoral photographs, and intraoral scans were analyzed. The collected data were used to compare the groups across five clinical parameters. Statistical analyses included the Mann-Whitney U-test, Wilcoxon signed-rank test, χ2 test, and Cochran's Q test, with significance set at P < .05.

Results: The impaction group had significantly longer treatment duration (mean = 2.64 ± 0.99 years) than controls (mean = 1.85 ± 0.60 years). Alveolar bone loss was significantly greater in teeth adjacent to the impacted canine and between the impacted and nonimpacted sides within the impaction group (P < .05). WSL incidence was higher in the impaction group, especially in posterior teeth (P = .0034). Root resorption patterns differed by region: maxillary incisors were more affected in the impaction group, whereas mandibular posterior teeth showed more resorption in controls. The use of auxiliary appliances was significantly greater in the impaction group.

Conclusions: Impacted canine treatment is associated with increased treatment time, greater alveolar bone loss, higher risk of WSLs, and distinct root resorption patterns. These findings highlight the importance of individualized treatment planning, careful biomechanical control, and preventive strategies in managing impacted canines.

Objectives: To determine if adhesive remnants and enamel loss after debonding and cleanup with a finishing bur were affected by hardness properties of the adhesive resins.

Materials and methods: Stainless steel orthodontic brackets (American Orthodontics, Mini Master series) were bonded on facial surfaces of extracted premolars using a relatively soft bioactive resin (ACTIVA BioACTIVE-Restorative, Pulpdent) or harder traditional adhesive (Transbond XT, 3M; N = 20/group). Bracketed teeth underwent 5000 thermocycles before brackets were debonded. Debonding surfaces were examined qualitatively and categorized by three examiners. Remaining adhesive was removed with a carbide finishing bur. Teeth were scanned with an optical scanner before brackets were bonded (baseline), after debonding, and after cleanup. Surface changes (mean thickness or depth, affected surface area, and volume) were calculated quantitatively after aligning scans to the baseline. Differences between the two groups were analyzed statistically with Mann-Whitney U-test or pairwise comparison at a significance level of 0.05.

Results: Qualitative examination of debonded surfaces did not show a significant difference (P = .7949) in adhesive remnants between groups, which was confirmed by quantitative evaluation (P > .05). After cleanup, enamel loss was significantly higher in the softer bioactive resin group (mean depth = 91 ± 16 µm, area = 24.48 ± 9.88 mm2) than the harder traditional adhesive (mean depth = 66 ± 9 µm, area = 6.34 ± 4.41 mm2; P < .0001).

Conclusions: The likelihood of adhesive remnants after debonding a bracket bonded with the bioactive resin was similar to traditional adhesive. However, enamel loss from cleaning up with a finishing bur was higher for the softer bioactive resin.

Objectives: To evaluate factors influencing the prediction error of artificial intelligence (AI) that predict craniofacial growth and to identify an optimal AI training condition to improve the predictive performance of the AI model.

Materials and methods: Original growth data were collected from the Mathews longitudinal serial growth study. From the original data consisting of 1257 datasets from 33 growing children of northern European descent, 60 data subsets were generated using random resampling procedures to include 12, 18, and 24 subjects, with data sizes of 100, 200, 300, 400, and 500 datasets. The resampling procedures were repeated four times. Each subset was used to train and create a total of 60 AI models. The prediction accuracy of these models was evaluated using growth prediction errors at the lower lip landmark, labrale inferius, as a benchmark indicator. The prediction errors of the 60 AI models were analyzed according to the number of subjects and data sizes.

Results: Prediction error decreased as the data size increased. However, increasing the number of subjects within the growth data led to higher prediction errors. Notably, the increase in prediction error caused by adding more subjects was more substantial than the improvement achieved by increasing the data size.

Conclusions: The findings suggest that developing highly accurate AI-based craniofacial growth prediction models remains a significant challenge, even with extensive datasets.

Objectives: To evaluate and compare the accuracy of four AI chatbots, ChatGPT-3.5, ChatGPT-4.0, Copilot, and Gemini, in response to orthodontic emergency scenarios.

Materials and methods: Forty frequently asked questions related to orthodontic emergencies were posed to the chatbots. These questions were categorized as fixed orthodontic treatment, clear aligner treatment, eating and oral hygiene, pain and discomfort, general concerns, retention, and sports and travel. The responses were evaluated by three orthodontic experts using a five-point Likert scale, and statistical analysis was conducted to assess variations in accuracy across chatbots.

Results: Statistical analysis revealed significant differences among the chatbots. Gemini and ChatGPT-4.0 demonstrated the highest accuracy in response to orthodontic emergencies, followed by Copilot, whereas ChatGPT-3.5 had the lowest accuracy scores. Additionally, the "Fixed Orthodontic Treatment" category showed a statistically significant difference (P = .043), with Gemini outperforming the other chatbots in this category. However, no statistically significant differences were found in other categories.

Conclusions: AI chatbots show potential in providing immediate assistance for orthodontic emergencies, but their accuracy varies across different models and question categories.

Objectives: To compare differential changes in nasal patency and dentoskeletal morphology after rapid palatal expansion (RPE) vs hybrid miniscrew-assisted rapid maxillary expansion (MARPE).

Materials and methods: Thirty patients presenting with bilateral crossbite were randomized into RPE or hybrid MARPE treatment groups. MARPE patients were treated using the two-point hyrax appliance and RPE patients were treated using the conventional hyrax appliance. Nasal patency was evaluated using rhinomanometry and dentoskeletal changes were evaluated using cone beam computed tomography images.

Results: The success of suture opening was 53% and 60% in the RPE (mean age: 17.36 ± 1.80) and MARPE groups (mean age: 18.52 ± 1.80), respectively. The MARPE group showed significantly increased nasal airflow and decreased nasal resistance during inspiration and expiration compared to the RPE group after 4 months of treatment. The RPE group demonstrated nonsignificant changes in the same parameters after 4 months. Although significant differences between groups were observed in nasal flow during inspiration and expiration for both nostrils, intergroup differences in nasal resistance were not significant (P > .05). The MARPE group exhibited greater expansion in nasal, maxillary basal, and alveolar widths compared to the RPE group. A more pronounced decrease in buccal bone thickness was observed in the RPE group. The buccal inclination of the first premolars and molars significantly increased in both groups.

Conclusions: Although similar success rates for sutural opening were observed between MARPE and RPE, MARPE facilitated more pronounced changes in nasal patency and skeletal maxillary expansion compared to conventional RPE.

Objectives: To evaluate the skeletal and dental effects of Class II correction in growing patients using clear aligners, with either elastics or mandibular advancement (MA).

Materials and methods: The study included 66 growing Class II patients: 45 patients treated with clear aligners (20 using Class II elastics and 25 with MA) and 21 untreated controls observed over a comparable time period. Nine cephalometric and three study cast measurements were evaluated initially (T1) and the end of treatment (T2) to assess skeletal and dental changes.

Results: The control group maintained a Class II molar relationship and overjet, whereas both treatment groups corrected to Class I. In the MA group, statistically significant skeletal changes from T1 to T2 were observed, including reduction in SNA (-1.09°) and ANB (-1.69°), in addition to dentoalveolar Class II correction. The elastic group showed no statistically significant changes in SNA and ANB compared to the control group. Linear regression revealed 5.28° of lower incisor proclination with Class II elastics, whereas lower incisor inclination was maintained with MA treatment.

Conclusions: Clear aligner treatment with Class II elastics and MA were effective for correcting Class II malocclusion in growing patients that would have otherwise been maintained without intervention. Although Class II correction was mainly due to dentoalveolar changes, a skeletal component was observed with MA treatment.

Objectives: To evaluate dentoskeletal effectiveness of deciduous molar anchorage in rapid maxillary expansion (RME) during mixed dentition.

Materials and methods: A comprehensive search was conducted across PubMed, MEDLINE, Scopus, and Cochrane Library databases from January 2000 to March 2025, adhering to PRISMA guidelines. Included studies comprised randomized controlled trials (RCTs) and non-RCTs assessing RME anchored to deciduous molars in patients with mixed dentition. Risk of bias (ROB) was assessed using ROB2 for RCTs and ROBINS-I for non-RCTs. Data were synthesized using a random-effects meta-analysis, focusing on dental and skeletal expansion.

Results: Seventeen studies (six RCTs, 11 retrospective) met the inclusion criteria. A meta-analysis of 12 studies demonstrated significant transverse changes in all evaluated areas: deciduous canines (4.27 mm), deciduous molars (5.51 mm), permanent molars (3.93 mm), and skeletal expansion (2.59 mm). Notably, dental expansion significantly exceeded skeletal expansion. Subgroup analyses comparing Haas and Hyrax expanders revealed no statistically significant differences in dentoskeletal expansion outcomes. However, heterogeneity across studies ranged from moderate to high. ROB assessments indicated moderate risk in all RCTs, whereas non-RCTs ranged from low to serious risk. Funnel plot inspection revealed no substantial asymmetry, suggesting a low likelihood of publication bias.

Conclusions: This meta-analysis confirms that deciduous molar anchorage in RME significantly increases dentoskeletal transverse dimensions. No significant differences emerged between appliance designs (Haas vs Hyrax). Despite consistent expansion effectiveness, variability in study design and ROB must be considered when interpreting these results.