Korean Journal of Orthodontics最新文献

{"title":"Written information versus multimedia education: A randomized trial on anxiety at the onset of orthodontic treatment in adolescents.","authors":"Mehmet Ali Yavan, Fırat Oğuz","doi":"10.4041/kjod25.127","DOIUrl":"10.4041/kjod25.127","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to compare the effects of multimedia and written explanations on anxiety, dental fear, and pain perception among adolescents before the start of fixed orthodontic treatment.</p><p><strong>Methods: </strong>Individuals aged 14-18 years who presented to the Faculty of Dentistry at Adıyaman University were randomly assigned to the multimedia information group (MIG) and written information groups (WIG). Before the appointment for bonding, educational information was provided to the MIG and WIG as an 8-minute informative multimedia video and written form, respectively. All participants completed the State-Trait Anxiety Inventory-State Anxiety and Dental Fear Index before and after the procedure. After the session, they were asked to rate their perceived pain using a visual analog scale and the number of questions they asked the clinician regarding the treatment was recorded. For statistical analyses, the Kolmogorov-Smirnov, chi-square, paired-sample <i>t</i> , Student <i>t</i>, and Mann-Whitney <i>U</i> tests were used.</p><p><strong>Results: </strong>No statistically significant differences in anxiety, fear, or pain scores were observed between the groups before and after the session (<i>P</i> > 0.05). Both groups exhibited no significant change in the anxiety scores between the two time points (<i>P</i> > 0.05), but exhibited significantly reduced fear scores (<i>P</i> < 0.05). Only the MIG demonstrated significant sex-related differences before the treatment session (<i>P</i> < 0.05).</p><p><strong>Conclusions: </strong>Although the effects of multimedia and written education on the anxiety and fear scores exhibited no significant different, multimedia education may have reduced the chair time by decreasing the number of questions posed by the patients.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"418-426"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460024/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy assessment of Smart stereolithography models generated by Dental Monitoring®: A pilot study.","authors":"Stratos Vassis, Dimitra Karamalaki, Jason Liu, Beatrice Noeldeke, Mohammedreza Sefidroodi, Sukeshana Srivastav, Julian Woolley, Peter Stoustrup","doi":"10.4041/kjod25.019","DOIUrl":"10.4041/kjod25.019","url":null,"abstract":"<p><strong>Objective: </strong>This pilot study aims to evaluate the clinical accuracy of Smart stereolithography (STL) files generated by the Dental Monitoring® (DM) system by comparing them with gold standard intraoral scans (IOSs).</p><p><strong>Methods: </strong>Seven aligner patients using the DM application were included. For each patient, Smart STL files generated from remote scans were superimposed onto IOSs using the best-fit algorithm in OnyxCeph software. Differences regarding inclination, angulation, rotation, buccal/lingual, mesial/distal, and intrusion/extrusion were quantified and statistically compared.</p><p><strong>Results: </strong>Statistically significant differences were observed in inclination, mesial/distal, and buccal/lingual movements, particularly in the posterior segments. However, all deviations remained within clinically acceptable thresholds for single aligner tooth movement.</p><p><strong>Conclusions: </strong>Despite minor deviations, Smart STL files generated by DM demonstrated sufficient accuracy for use in aligner planning and refinement. These findings highlight the potential of DM-generated Smart STL files for subsequent aligner treatment.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"349-354"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460025/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Infectious repetitis</i>: Repeated inventions of easy but unsound solutions.","authors":"Sung-Hoon Lim","doi":"10.4041/kjod55.5E","DOIUrl":"10.4041/kjod55.5E","url":null,"abstract":"","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"335-336"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460021/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative mechanical performance of thermoplastic materials for clear aligners under simulated oral conditions.","authors":"Miao Liu, Yajie Wang, Ce Bian, Yang Han, Xuan Qin, Jingyao Sun, Yuxing Bai, Ning Zhang","doi":"10.4041/kjod25.094","DOIUrl":"10.4041/kjod25.094","url":null,"abstract":"<p><strong>Objective: </strong>To assess the suitability of polycyclohexylenedimethylene terephthalate glycol (PCTG) for orthodontic aligners and to compare the mechanical properties and 14-day stress relaxation behavior of different materials under simulated oral conditions, offering clinical guidance for material selection.</p><p><strong>Methods: </strong>Materials used were Maxflex, Scheu, and Fusion Align, consisting of thermoplastic polyurethane (TPU), polyethylene terephthalate glycol (PETG), and PCTG, respectively. The following experiments were conducted: (1) tensile testing at 23°C and under simulated oral conditions; (2) prediction of 14-day stress relaxation using the time-temperature superposition principle; (3) right-angle tear strength testing; and (4) Shore D hardness testing.</p><p><strong>Results: </strong>Mechanical properties followed the trend TPU > PETG > PCTG in elastic modulus, yield strength, right-angle tear strength, and Shore D hardness (<i>P</i> < 0.05); PETG > PCTG > TPU in yield strain (<i>P</i> < 0.05). TPU showed higher elongation at break than PETG and PCTG (<i>P</i> < 0.05), with no significant difference between PETG and PCTG (<i>P</i> > 0.05). Stress relaxation behavior was predicted based on the time-temperature superposition principle. With prolonged duration, the stress ranking progressively shifted from TPU > PETG > PCTG to PCTG > PETG > TPU.</p><p><strong>Conclusions: </strong>PCTG exhibits light and sustained force, but its tear resistance and hardness are relatively low. In contrast, TPU demonstrates excellent tear resistance and hardness but experiences rapid force decay.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"380-391"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460023/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of machine learning-assisted prediction of the future need for orthognathic surgery in patients with cleft lip and palate.","authors":"Seung-Weon Lim, Eunghee Kim, Hong-Gee Kim, Seung-Hak Baek","doi":"10.4041/kjod25.030","DOIUrl":"10.4041/kjod25.030","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the accuracy of machine learning (ML)-assisted prediction of the need for orthognathic surgery (OGS) in patients with cleft lip and palate (CLP).</p><p><strong>Methods: </strong>This study included 245 patients with CLP whose lateral cephalograms were available at pre-adolescence (T0; mean age, 8.45 years) and young adulthood (T1; mean age: 18.37 years). At T1, the patients were classified into the surgery group based on two criteria: (1) satisfying at least three of the following four conditions: ANB < -3°, Wits appraisal < -5 mm, APDI > 90°, and AB-MP < 60° and (2) undergoing presurgical orthodontic treatment or having undergone OGS. A total of 25.3% (n = 62) of patients were assigned to the surgery group, while 74.7% (n = 183) were assigned to the non-surgery group. Further, 80% and 20% of each group were used as training/validation and test sets, respectively. After 37 cephalometric variables and two cleft-related variables were measured, support vector machine (SVM) and feature importance analysis (FIA) with Shapley additive explanation were used to determine the prediction accuracy and predictors at T0.</p><p><strong>Results: </strong>SVM demonstrated area under curve 0.84, accuracy 83.7%, sensitivity 83.3%, and specificity 83.8%. FIA revealed 10 predictors: A to N-perpendicular, L1 to A-Pog, Pog to N-perpendicular, L1 to Lower-occlusal plane, Cleft type, U1 to Upper-occlusal plane, IMPA, gonial angle, anteroposterior facial height ratio, and ANB with accumulated importance of 64.51%.</p><p><strong>Conclusions: </strong>The ML algorithm used in this study may support clinical decision-making in identifying candidates for future OGS at 8 years of age.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"365-379"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460019/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of artificial intelligence-assisted soft tissue landmark identification in serial lateral cephalograms of Class III two-jaw surgery patients.","authors":"Sun Hyong Kim, Inhwan Kim, Jin-Hyoung Cho, Kyung-Hwa Kang, Minji Kim, Su-Jung Kim, Yoon-Ji Kim, Sang-Jin Sung, Young Ho Kim, Sung-Hoon Lim, Seung-Hak Baek, Namkug Kim, Mihee Hong","doi":"10.4041/kjod24.302","DOIUrl":"10.4041/kjod24.302","url":null,"abstract":"<p><strong>Objective: </strong>To evaluate the accuracy of artificial intelligence (AI)-assisted soft tissue landmark identification (STLI) on serial lateral cephalograms (Lat-Cephs) of Class III patients treated with two-jaw orthognathic surgery across four different time-points.</p><p><strong>Methods: </strong>A convolutional neural network model was developed for STLI, trained and validated using 3,004 Lat-Cephs from 751 patients. The test set included 224 Lat-Cephs from 56 patients, divided into the genioplasty (n = 22) and non-genioplasty (n = 34) groups. The four time-points included initial (T0), pre-surgery (T1, brackets), post-surgery (T2, brackets, surgical plates, and screws [S-PS]), and debonding (T3, S-PS and fixed retainers). AI accuracy was compared with a human standard for 13 soft tissue landmarks. Mean radial errors (MREs), horizontal and vertical errors, and statistical differences were analyzed.</p><p><strong>Results: </strong>The total MRE across all time-points was 1.50 ± 0.48 mm, with 64.9% of values being less than 1.5 mm MRE. There were no significant differences in accuracy among the four time-points (T0, 1.41 mm; T1, 1.53 mm; T2, 1.58 mm; T3, 1.47 mm). The pronasale, stomion inferius (Stmi), stomion superius (Stms) showed an increase in MRE (<i>P</i> < 0.01, <i>P</i> < 0.05, and <i>P</i> < 0.05, respectively), whereas the Lower Lip showed a decrease in MRE (<i>P</i> < 0.01). There were no significant differences in errors across time-points for the soft-tissue B point, soft-tissue Pogonion, or soft-tissue Menton between the genioplasty and non-genioplasty groups.</p><p><strong>Conclusions: </strong>The AI algorithm in this study might be an effective tool for STLI in Lat-Cephs at T1, T2, and T3, despite the presence of brackets, S-PS, fixed retainers, genioplasty, and bone remodeling.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"392-404"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460026/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the feasibility of a stainless-steel lingual fixed retainer on mandibular anterior dentition with orthodontic-related labiolingual alveolar bone resorption: A finite element analysis.","authors":"Yinyin Zhang, Liwei Xiao, Xinyue Cao, Yunting Zeng","doi":"10.4041/kjod24.148","DOIUrl":"10.4041/kjod24.148","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to evaluate the use of a stainless-steel fixed retainer for post-orthodontic retention in patients with labiolingual alveolar bone resorption in the mandibular anterior segment.</p><p><strong>Methods: </strong>Three mandibular anterior segment models (with or without labial or lingual alveolar bone resorption) with 0.5-mm-diameter retainers bonded to all teeth were constructed. Two occlusion schemes were simulated: a 285.3 N force applied to four mandibular incisors (incisor biting) and a 93 N force applied to the left canine (laterotrusion). The tooth displacement and stress distribution in the periodontal ligament (PDL), retainer, and composite were evaluated.</p><p><strong>Results: </strong>Compared to no resorption, labial bone resorption significantly increased tooth displacement and PDL stress concentration in the central incisors during incisor biting, whereas lingual resorption had a greater effect on the guiding canine during laterotrusion. The retainers were susceptible to stress concentrations in the resin-uncovered area, mesial region of the lateral incisors under incisor biting, and mesial region of the guiding canine under laterotrusion. For the composite, the composite-retainer interface was prone to stress concentrations, especially in the mesial or distal extremes of the adhesive composite of the incisors.</p><p><strong>Conclusions: </strong>A 0.5-mm-diameter stainless-steel lingual retainer bonded on all teeth is a clinically acceptable retention procedure for patients with lingual bone resorption in the lower anterior region. However, it should be used more cautiously for patients with labial bone resorption as it exposes the lower central incisors to a greater risk. Excessive stress on the retainer and composite due to the occlusion force may lead to unwanted tooth movement, necessitating closer monitoring.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"337-348"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460022/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histological response of the periodontal tissue to mandibular incisor movement using clear aligners of varying thickness in a rabbit model.","authors":"Yue Wang, He Liu, Yueming Li, Liwen Zhang, Xun Yan, Ruoxi Liu, Xiao Shen, Baohua Xu, Qiang Sun","doi":"10.4041/kjod25.115","DOIUrl":"10.4041/kjod25.115","url":null,"abstract":"<p><strong>Objective: </strong>Investigate the histological response of the periodontal tissue to incisor movement using varying-thickness clear aligners in a rabbit model.</p><p><strong>Methods: </strong>Thirty-three New Zealand rabbits were randomly assigned to two experimental groups (0.38-mm and 0.68-mm aligners) and a control group. Each rabbit in the experimental group wore three sequential aligners, which were changed every 5 days. Orthodontic force was measured using a uniaxial force sensor, and tooth movement was quantified using three-dimensional imaging. Root resorption was assessed using micro-computed tomography. Histological and immunohistochemical staining and real-time quantitative reverse transcription polymerase chain reaction tests were performed to evaluate the periodontal tissue response.</p><p><strong>Results: </strong>The 0.68-mm aligners generated larger forces than the 0.38-mm aligners. Tooth movement was faster with the third 0.38-mm aligner, with no statistically significant differences between the two groups. Both groups exhibited minor root resorption, with the 0.68-mm group exhibiting larger resorption craters. Additionally, the 0.68-mm group demonstrated more significant deformation of periodontal fibers and increased expression of inflammatory markers. The 0.38-mm group showed a larger number of osteoclasts on the compression side.</p><p><strong>Conclusions: </strong>Both aligners achieved effective tooth movement. The 0.38-mm aligners exerted smaller forces and enabled slightly faster movements than the 0.68-mm aligners. Although both groups showed minimal root resorption, the 0.68-mm group exhibited larger resorption craters. Furthermore, the 0.38-mm group exhibited less histological deformation and inflammation in the periodontal tissues. These results suggest that aligner thickness can be tailored to customize treatments. Further studies with longer observation periods and more refined methodologies are warranted.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"405-417"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460027/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"READER'S FORUM.","authors":"Mariam Al-Samman, Mais Sadek, Ahmad M Hamdan","doi":"10.2319/080508-352.1","DOIUrl":"10.2319/080508-352.1","url":null,"abstract":"","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"333-334"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460020/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differences in the posterior space available for molar distal movement according to the presence and position of the third molar: A cone-beam computed tomography study.","authors":"Seong-Jun Moon, Ho-Jin Kim, Hyung-Kyu Noh, Mihee Hong, Hyo-Sang Park","doi":"10.4041/kjod25.017","DOIUrl":"10.4041/kjod25.017","url":null,"abstract":"<p><strong>Objective: </strong>To assess differences in the available posterior space for molar distal movement according to the presence and three-dimensional position of third molars.</p><p><strong>Methods: </strong>This study included 46 and 59 patients for the maxilla and mandible, respectively. The patients were assigned to third molar and no-third molar groups. Retromolar distances were measured at different vertical root levels of the second molar. The positions and axial angulations of the third molars were also examined. An independent <i>t</i> test or Mann-Whitney <i>U</i> test was performed to compare the retromolar distance between groups. The Pearson correlation coefficient was calculated to investigate the relationship between retromolar distance and age or third molar variables.</p><p><strong>Results: </strong>The retromolar distance was shortest at the 2 mm apical level in the maxilla and at the 10 mm apical level in the mandible. The maxillary retromolar distance of the distobuccal root was significantly longer at all apical levels in the third molar group than in the no-third molar group (<i>P</i> < 0.01), but was not significantly different at the 10 mm apical level in the mandible (<i>P</i> = 0.969). The number of buccally positioned third molars in the mandible was significantly higher than that in the maxilla (<i>P</i> < 0.001). The shortest retromolar distance in both jaws was not significantly associated with age, the third molar's position, or eruption status.</p><p><strong>Conclusions: </strong>The available posterior space with the third molar present was significantly larger than that without the third molar in the maxilla, but was not significantly different in the mandibular posterior space.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"55 5","pages":"355-364"},"PeriodicalIF":2.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12460028/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145126508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}