{"title":"Intraoral ageing of aligners and attachments: Adverse effects on clinical efficiency and release of biologically-active compounds.","authors":"Theodore Eliades, George Eliades","doi":"10.4041/kjod24.085","DOIUrl":"10.4041/kjod24.085","url":null,"abstract":"<p><p>The clinical application of aligners is accompanied by the ageing of the polymer appliances and the attachments used, which may result in inefficiency in reaching the predicted range of tooth movement, and release of compounds and microplastics in the oral cavity as a result of the friction, wear and attrition of the aligner and composite attachment. The purpose of this review is to present the mechanism and effects of <i>in vivo</i> ageing; describe the hydrolytic degradation of aligners and enzymatic degradation of composite attachments; examine the ageing pattern of aligners <i>in vivo</i>, under actual clinical scenarios; and identify a link to the discrepancy between predicted and actual clinical outcome. Lastly, strategies to deal with three potentially critical issues associated with the use of aligners, namely the necessity of weekly renewal, the dissimilar mechanical properties of aligner and attachment resulting in wear and plastic deformation of the aligner, and the development of integuments and biofilms with microbial colonization of the appliance, are discussed.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":" ","pages":"199-209"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270147/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141460648","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}
Federica Guglielmi, Anna Alessandri-Bonetti, Geraldine Gemelli, Linda Sangalli, Patrizia Gallenzi
{"title":"Prevalence of malocclusions and parafunctional habits in pediatric patients with developmental dyslexia.","authors":"Federica Guglielmi, Anna Alessandri-Bonetti, Geraldine Gemelli, Linda Sangalli, Patrizia Gallenzi","doi":"10.4041/kjod23.256","DOIUrl":"10.4041/kjod23.256","url":null,"abstract":"<p><strong>Objective: </strong>The study aimed to assess the prevalence of dental malocclusion, orthodontic parameters, and parafunctional habits in children with developmental dyslexia (DD).</p><p><strong>Methods: </strong>Forty pediatric patients (67.5% boys and 32.5% girls, mean age: 11.02 ± 2.53 years, range: 6-15 years) with DD were compared with 40 age- and sex-matched healthy participants for prevalence of dental malocclusion, orthodontic parameters, and parafunctional habits. Dental examinations were performed by an orthodontist.</p><p><strong>Results: </strong>Pediatric patients with DD exhibited a significantly higher prevalence of Angle Class III malocclusion (22.5% vs. 5.0%, <i>P</i> = 0.024), deep bite (27.5% vs. 7.5%, <i>P</i> = 0.019), midline deviation (55.0% vs. 7.5%, <i>P</i> < 0.0001), midline diastemas (32.5% vs. 7.5%, <i>P</i> = 0.010), wear facets (92.5% vs. 15.0%, <i>P</i> < 0.0001), self-reported nocturnal teeth grinding (82.5% vs. 7.5%, <i>P</i> < 0.0001), nail biting (35.0% vs. 0.0%, <i>P</i> < 0.0001), and atypical swallowing (85.0% vs. 17.5%, <i>P</i> < 0.0001) compared to that in healthy controls.</p><p><strong>Conclusions: </strong>Pediatric patients with DD showed a higher prevalence of Class III malocclusion, greater orthodontic vertical and transverse discrepancies, and incidence of parafunctional activities. Clinicians and dentists should be aware of the vulnerability of children with dyslexia for exhibiting malocclusion and encourage early assessment and multidisciplinary intervention.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"54 4","pages":"229-238"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270149/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141762486","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}
Tuan Khang Nguyen, Akanksha Cambala, Manuela Hrit, Elizabeth A Zimmermann
{"title":"A scoping review of cephalometric normative data in children.","authors":"Tuan Khang Nguyen, Akanksha Cambala, Manuela Hrit, Elizabeth A Zimmermann","doi":"10.4041/kjod23.224","DOIUrl":"10.4041/kjod23.224","url":null,"abstract":"<p><strong>Objective: </strong>Understanding the orofacial characteristics and growth patterns in children is essential for both orthodontics and research on children with orofacial abnormalities. However, a concise resource of normative data on the size and relative position of these structures in different populations is not available. Our objective was to aggregate normative data to assess the growth of the orofacial skeletal structures in children with a well-balanced face and normal occlusion.</p><p><strong>Methods: </strong>The MEDLINE, Embase, and Scopus databases were searched. Inclusion criteria included longitudinal and cross-sectional studies on cephalometric measurement of skeletal tissues and a study population ≤ 18 years with a well-balanced face and normal occlusion. Key study parameters were extracted, and knowledge was synthesized. A quality appraisal was performed using a 10-point scale.</p><p><strong>Results: </strong>The final selection comprised of 12 longitudinal and 33 cross-sectional studies, the quality of which ranged from good to excellent. Our results showed that from childhood to adulthood, the length of the cranial base increased significantly while the cranial base angle remained constant; both the maxilla and mandible moved forward and downward. The profile becomes straighter with age.</p><p><strong>Conclusions: </strong>Growth patterns in children with a well-balanced face and normal occlusion follow accepted theories of growth.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":" ","pages":"210-228"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270148/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141428270","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}
Osman Küçükçakır, Nilüfer Ersan, Yunus Ziya Arslan, Erol Cansız
{"title":"Evaluation of mandibular condyle position in Class III patients after bimaxillary orthognathic surgery: A cone-beam computed tomography study.","authors":"Osman Küçükçakır, Nilüfer Ersan, Yunus Ziya Arslan, Erol Cansız","doi":"10.4041/kjod23.188","DOIUrl":"10.4041/kjod23.188","url":null,"abstract":"<p><strong>Objective: </strong>This retrospective study evaluated the mandibular condyle position before and after bimaxillary orthognathic surgery performed with the mandibular condyle positioned manually in patients with mandibular prognathism using cone-beam computed tomography.</p><p><strong>Methods: </strong>Overall, 88 mandibular condyles from 44 adult patients (20 female and 24 male) diagnosed with mandibular prognathism due to skeletal Class III malocclusion who underwent bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I performed using the manual condyle positioning method were included. Cone-beam computed tomography images obtained 1-2 weeks before (T0) and approximately 6 months after (T1) surgery were analyzed in three planes using 3D Slicer software. Statistical significance was set at <i>P</i> < 0.05 level.</p><p><strong>Results: </strong>Significant inward rotation of the left mandibular condyle and significant outward rotation of the right mandibular condyle were observed in the axial and coronal planes (<i>P</i> < 0.05). The positions of the right and left condyles in the sagittal plane and the distance between the most medial points of the condyles in the coronal plane did not differ significantly (<i>P</i> > 0.05).</p><p><strong>Conclusions: </strong>While the change in the sagittal plane can be maintained as before surgery with manual positioning during the BSSRO procedure, significant inward and outward rotation was observed in the axial and coronal planes, respectively, even in the absence of concomitant temporomandibular joint disorder before or after the operation. Further long-term studies are needed to correlate these findings with possible clinical consequences.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":" ","pages":"247-256"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141565066","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 lingual fixed retainers fabricated using a CAD/CAM bending machine.","authors":"Fu Ping Cui, Jung-Jin Park, Seong-Hun Kim","doi":"10.4041/kjod24.078","DOIUrl":"10.4041/kjod24.078","url":null,"abstract":"<p><strong>Objective: </strong>Lingual fixed retainers, made from 0.0175-inch 3-strand twisted stainless steel wire (TW) and 0.016 × 0.022-inch straight rectangular wire (RW), are generally used in clinical practice. This study aimed to calculate their accuracy by comparing the discrepancy between computer-aided customized retainers made from these two types of wires.</p><p><strong>Methods: </strong>Eleven orthodontic patients were selected, resulting in 22 maxillary and mandibular three-dimensional printing dental models. Two types of lingual fixed retainers were bonded from canine to canine. To determine the accuracy, five points were chosen for each model, resulting in 110 selected points. The absolute values of the distances on the x-, y-, and z-axes were measured to compare the accuracy of the two types of computer-aided retainers.</p><p><strong>Results: </strong>The accuracy of the two types of retainers did not differ significantly in the x- and z-axes, but only in the y-axis (<i>P</i> < 0.01), where RW-fixed retainers exhibited a slightly but significantly increased distance compared to the TW.</p><p><strong>Conclusions: </strong>Both types of retainers showed high accuracy; however, RW had a slight but statistically significant difference along the y-axis compared with TW. This type of computer-aided design/computer-aided manufacturing bending machine is limited to two dimensions, and the dental arch is curved. Therefore, RW may require slight manual adjustment by the practitioner after manufacturing.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"54 4","pages":"257-263"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270144/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141762485","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":"Tricortical versus bicortical anchorage in a double-screw tandem skeletal expander and a single-screw maxillary anchorage rapid palatal expander: A finite element analysis.","authors":"Luca Brucculeri, Federica Pellitteri, Alfredo Salvatore Monterossi, Emanuele Paoletto, Giuliano Maino, Luca Lombardo","doi":"10.4041/kjod23.270","DOIUrl":"https://doi.org/10.4041/kjod23.270","url":null,"abstract":"<p><strong>Objective: </strong>This study aims to employ finite element method (FEM) analysis to compare the differences between bicortical and tricortical anchorage of the posterior miniscrews in a single-screw miniscrew-assisted rapid palatal expansion (MARPE) and a double-screw tandem skeletal expander (TSE) under open and closed suture conditions.</p><p><strong>Methods: </strong>A cone beam computed tomography of the human skull of a 21.5-year-old female was utilized as a model for creating a FEM analysis. Simulations involved the insertion of four palatal miniscrews: two anterior ones with bicortical anchorage and two posterior ones (one with bicortical and another with tricortical anchorage), under open and closed suture conditions in a single-screw MARPE and double-screw TSE, resulting in a total of eight different simulation configurations. Evaluation parameters include total deformation (mm), Von Mises stress (MPa), and strain for each miniscrew body.</p><p><strong>Results: </strong>Tricortical anchorage of the posterior miniscrews provides greater anchorage, higher stress, and deformation on the anterior miniscrews in single-screw MARPE. Tricortical anchorage combined with a double-screw TSE promotes a more even distribution of force and stress on miniscrews under open suture conditions, leading to a parallel midpalatal suture opening along its entire length and height.</p><p><strong>Conclusions: </strong>FEM analysis revealed favorable midpalatal suture opening with equal force distribution and less stress when posterior tricortical anchorage in conjunction with double-screw TSE is applied.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141762456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diego Fernando López, David Acosta Olmos, Mónica Andrea Morales
{"title":"Anatomical factors of the maxillary tuberosity that influence molar distalization.","authors":"Diego Fernando López, David Acosta Olmos, Mónica Andrea Morales","doi":"10.4041/kjod24.017","DOIUrl":"10.4041/kjod24.017","url":null,"abstract":"<p><strong>Objective: </strong>To examine the areas of the maxillary tuberosity (MT) (coronal, apical, width, and height) with respect to the presence or absence of the third molar to establish possible anatomical limitations for molar distalization.</p><p><strong>Methods: </strong>A total of 277 tuberosities were evaluated through sagittal computed tomography (CT) images, divided for measurement into coronal (free of bone), apical (area of influence of the maxillary sinus), and tuberosity (bony area) zones, and stratified by the presence or absence of the third molar, sex, and two age subgroups. Mann-Whitney <i>U</i> test was used to compare the groups considering the third molar.</p><p><strong>Results: </strong>The medians of the width and height of the tuberosity decreased significantly in the absence of the third molar (<i>P</i> < 0.001). The apical area also showed differences, with negative values in the absence of the third molar and positive values in the presence of the third molar (<i>P</i> < 0.001). However, no differences were observed for the coronal area (<i>P</i> > 0.05).</p><p><strong>Conclusions: </strong>In the absence of the third molar, the size of the MT, represented by its width and height, was smaller and negative values (decrease) were observed for the maxillary sinus. The sagittal CT provides useful information regarding the amount of bone tissue available for distalization and relationship of the second molar with respect to the maxillary sinus, which allows individualizing each case in relation to the amount and type of movement expected.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":" ","pages":"239-246"},"PeriodicalIF":2.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270146/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141421788","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}
Maziar Nobahari, Fatemeh Safari, Allahyar Geramy, Tabassom Hooshmand, Mohammad Javad Kharazifard, Sepideh Arab
{"title":"Effect of three common hot beverages on the force decay of orthodontic elastomeric chain within a 28-day period: An <i>in vitro</i> study.","authors":"Maziar Nobahari, Fatemeh Safari, Allahyar Geramy, Tabassom Hooshmand, Mohammad Javad Kharazifard, Sepideh Arab","doi":"10.4041/kjod23.160","DOIUrl":"10.4041/kjod23.160","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to assess the effects of commonly consumed hot drinks on the force decay of orthodontic elastomeric chains.</p><p><strong>Methods: </strong>This <i>in vitro</i> experimental study evaluated 375 pieces of elastomeric chains with six rings placed on a jig. Four rings were stretched by 23.5 mm corresponding to the approximate distance between the canine and the second premolar. Fifteen pieces served as reference samples at time zero, and 360 pieces were randomized into four groups: control, hot water, hot tea, and hot coffee. Each group was further divided into six subgroups (n = 15) according to the different exposure periods. The specimens in the experimental groups were exposed to the respective solutions at 65.5°C four times per day for 90 seconds at 5-second intervals. The control group was exposed to artificial saliva at 37°C. The force decay of the samples was measured at 1, 2, 7, 14, 21, and 28 days using a universal testing machine. Data were analyzed using repeated-measures analysis of variance.</p><p><strong>Results: </strong>Maximum force decay occurred on day 1 in all groups. The minimum force was recorded in the control group, followed by the tea, coffee, and hot water groups on day 1. At the other time points, the minimum force was observed in the tea group, followed by the control, coffee, and hot water groups.</p><p><strong>Conclusions: </strong>Patients can consume hot drinks without concern about any adverse effect on force decay of the orthodontic elastomeric chains.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"54 3","pages":"153-159"},"PeriodicalIF":1.9,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11129932/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141155858","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}
Marco Migliorati, Sara Drago, Tommaso Castroflorio, Paolo Pesce, Giovanni Battista, Alessandra Campobasso, Giorgio Gastaldi, Filippo Forin Valvecchi, Anna De Mari
{"title":"Accuracy of orthodontic movements with 3D printed aligners: A prospective observational pilot study.","authors":"Marco Migliorati, Sara Drago, Tommaso Castroflorio, Paolo Pesce, Giovanni Battista, Alessandra Campobasso, Giorgio Gastaldi, Filippo Forin Valvecchi, Anna De Mari","doi":"10.4041/kjod23.268","DOIUrl":"10.4041/kjod23.268","url":null,"abstract":"<p><strong>Objective: </strong>Owing to the availability of 3D software, scanners, and printers, clinicians are encouraged to produce in-office aligners. Recently, a new directprinting resin (Tera Harz TC-85DAC) has been introduced. Studies on its mechanical characteristics and biological effects have been published; however, evidence on its efficacy in orthodontic treatment remains scarce. This pilot study aimed to investigate the accuracy of teeth movement achieved with directprinted aligners.</p><p><strong>Methods: </strong>Seventeen patients (eight males and nine females) with a mean age of 27.67 ± 8.95 years, presenting with dental rotations < 30° and spaces/crowding < 5 mm, were recruited for this study. The teeth movement was planned starting from a T0 digital dental cast. The 3D direct-printed aligners were produced using Tera Harz TC-85DAC resin. Once the orthodontic treatment was completed, a final digital cast was obtained (T1). The planned teeth positions were then superimposed onto the T0 and T1 digital models. The differences between the programmed movements and the achieved overall torque, tip, rotation, and transverse dimensions were assessed using the paired t test or Wilcoxon's signed rank test.</p><p><strong>Results: </strong>The overall accuracies for torque, tip, and rotation were 67.6%, 64.2%, and 72.0%, respectively. The accuracy of the change in transverse diameter was 99.6%.</p><p><strong>Conclusions: </strong>Within the limits of the present pilot study (difficulties with abnormally shaped teeth and use of attachments), it can be concluded that 3D printed aligners can be successfully printed in-house and utilized for mildly crowded cases, with a comparable accuracy of tooth movement to that of other aligners.</p>","PeriodicalId":51260,"journal":{"name":"Korean Journal of Orthodontics","volume":"54 3","pages":"160-170"},"PeriodicalIF":1.9,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11129935/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141155829","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}