Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie最新文献

{"title":"Changes in strain energy density in the temporomandibular joint disk after sagittal split ramus osteotomy using a computed tomography-based finite element model.","authors":"Kazuhiro Murakami, Kazuhiko Yamamoto, Masayoshi Kawakami, Satoshi Horita, Tadaaki Kirita","doi":"10.1007/s00056-022-00441-3","DOIUrl":"10.1007/s00056-022-00441-3","url":null,"abstract":"<p><strong>Purpose: </strong>We evaluated the changes in the strain energy density (SED) in the temporomandibular joint (TMJ) disk after sagittal split ramus osteotomy (SSRO) at three time points. A finite element model (FEM) based on real patient-based computed tomography (CT) data was used to examine the effect of SSRO on the TMJ.</p><p><strong>Methods: </strong>Measurements of the condylar position and angulation in CT images and FEM analyses were performed for 17 patients scheduled to undergo SSROs at the following time points: before surgery, immediately after surgery, and 1 year after surgery. SED on the entire disk was calculated at each of the three time points using FEM. Furthermore, the relationship between individual SED values and the corresponding condylar position was also evaluated.</p><p><strong>Results: </strong>No significant change was observed in the condylar position at the three time points. The FEM analysis showed that SED was the highest and lowest immediately after and 1 year after surgery, respectively. A possible SED distribution imbalance between the left and right joints was improved 1 year after SSRO. Concerning the effect of fossa morphometry and condylar position, wide and deep glenoid fossae and a more posterior condylar position tended to show lower SED.</p><p><strong>Conclusion: </strong>SED in the articular disk temporarily increased after surgery and significantly decreased 1 year after surgery compared with that before surgery. SSRO generally improved the imbalance between the left and right joints. Thus, SSRO, which improves maxillofacial morphology, may also improve components of temporomandibular disorders.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10513794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of offset design on the accuracy of bracket placement with a guided bonding device.","authors":"Bin Li, Peiqi Wang, Hui Xu, Rui Gu, Xianglong Han, Ding Bai, Chaoran Xue","doi":"10.1007/s00056-022-00424-4","DOIUrl":"10.1007/s00056-022-00424-4","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to evaluate the effects of offset design on the accuracy of bracket placement for computer-aided design and computer-aided manufacturing (CAD/CAM)-guided bonding devices (GBDs) in vitro.</p><p><strong>Methods: </strong>Eight dental models were selected. Seven types of GBDs were designed and three-dimensionally (3D) printed for each model, including one without any offset and the other six with translation offsets (TF) and expansion offsets (EF) of 0.05, 0.10, and 0.15 mm, respectively. After the brackets were bonded on the models using the different GBDs in vitro, linear and angular deviations of the bracket positions were evaluated.</p><p><strong>Results: </strong>In total, 56 GBDs were printed, and 784 brackets were bonded using the GBDs. No misfit between the dentitions and the devices was found during the bonding process. With increasing offset, more brackets were gingivally positioned with the frequencies ranging from 61.61 to 76.79% for the TF groups and from 58.93 to 78.57% for the EF groups. The vertical deviations of the brackets increased from 0.100 to 0.168 mm and from 0.117 to 0.150 mm in the TF and the EF group, respectively, as offset increased. No statistically significant difference was found in the vertical deviation between most of the TF and EF groups with the same offset value (p > 0.05). With respect to angulation, the mean absolute deviations were 0.881, 1.083, and 1.029° in the 0.05-mm, 0.10-mm, and 0.15-mm EF groups, respectively, which were greater than those in the corresponding TF groups (0.799, 0.847, and 0.806°). Similarly, with increasing offset, the mean absolute deviations for rotation in the EF groups (0.847, 0.998, and 1.138°) were greater than those in the TF groups (0.853, 0.946, and 0.896°). Compared with the 0.15-mm TF group, greater angulations (p < 0.05) and rotations (p < 0.01) were found in the 0.15-mm EF group.</p><p><strong>Conclusions: </strong>Offset designs influenced the precision of vertical bracket placement with GBDs. Due to the smaller deviations in angulation and rotation of bracket placement, TF is preferred over EF for GBDs. Moreover, the differences between TF and EF also need to be considered in the design of other dental CAD/CAM devices.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40356551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cephalometric analysis of parents of patients with cleft lip and/or palate.","authors":"H Hari Kishore Bhat, Venkatesh Anehosur, Varsha Haridas Upadya, Niranjan Kumar, Vijayanand Madhur","doi":"10.1007/s00056-022-00435-1","DOIUrl":"10.1007/s00056-022-00435-1","url":null,"abstract":"<p><strong>Background: </strong>Cleft lip and/or palate (CL ± P) or isolated cleft palate (CP) are the most common congenital malformations of the face. Although there have been advances in prenatal diagnosis and the discovery of genetic markers, there has been no breakthrough in the identification of parents at risk of giving birth to a child with a cleft.</p><p><strong>Aims: </strong>To determine a possible phenotypic difference in the craniofacial morphology of parents of children with CL ± P and to investigate whether cephalometric analysis can help identify parents at risk of giving birth to a child with a cleft.</p><p><strong>Methods: </strong>Cephalometric data of 25 sets of parents having children with CL ± P were compared with that of 25 sets of parents of children without CL ± P. The study population was indigenous to North Karnataka. In all, 10 linear, 2 angular, and 5 triangular measurements were made on lateral cephalograms and compared using an unpaired t‑test.</p><p><strong>Results: </strong>The length of the posterior cranial base (S-Ba) in mothers was smaller in the study compared to the control group. Total facial height (N-Me) both in fathers and in the group with both parents, upper facial height in the group with both parents, and lower facial height (ANS-Me) in fathers was smaller in the study than in the control group. The area of the nasopharyngeal triangle (S-PNS-Ba) in mothers and that of the anterior maxillary triangle (S-N-A) in fathers was smaller in the study group than in the control group.</p><p><strong>Conclusion: </strong>Parents of children with CL ± P showed variations in craniofacial morphology. Future research correlating cephalometric findings with genetic studies may indicate whether cephalometric analysis can be an adjunct to genetic tests for risk prediction among susceptible parents.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10374580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term (≥ 15 years) outcome quality after Class II:1 bionator or Herbst multibracket appliance treatment : A comparison.","authors":"Niko Christian Bock, Rebecca Jungbauer, Ingrid Rudzki, Peter Proff, Sabine Ruf","doi":"10.1007/s00056-023-00457-3","DOIUrl":"10.1007/s00056-023-00457-3","url":null,"abstract":"<p><strong>Purpose: </strong>To compare the long-term outcome quality (≥ 15 years) of Class II:1 treatment using either a bionator (BIO) or a Herbst-multibracket appliance (HMB).</p><p><strong>Methods: </strong>Patients who underwent functional treatment during the ideal treatment period for the respective approach (prepuberty vs. peak/postpeak) were assessed. Inclusion criteria were overjet ≥ 4 mm, skeletal Class II and availability of study casts from before, after and ≥ 15 years after treatment. The study casts were assessed using the Peer Assessment Rating (PAR) index and standard orthodontic cast measurements.</p><p><strong>Results: </strong>During treatment, PAR score, overjet and sagittal occlusal relationship improved significantly in all groups. Long-term, there was a significant increase of incisor irregularity in the upper (HMB) and lower (BIO) arch and a significant decrease of lower arch width 3 - 3 (BIO). PAR score, overjet, and sagittal occlusal relationship remained stable long-term. Intergroup comparisons revealed significant differences between the BIO and HMB groups in terms of lower arch width (6 - 6), upper and lower arch width (3 + 3/3 - 3) as well as sagittal molar relationship.</p><p><strong>Conclusions: </strong>The achieved improvement in PAR score, overjet, and sagittal occlusion remained comparably stable long-term in all groups. The long-term changes are probably a consequence of natural aging.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11186930/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10770421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between the mandibular curve of Spee and the maxillary compensating curve with dentoskeletal morphology : A cross-sectional study in Chinese young adults with normal occlusion.","authors":"Pei Xiao, Yanfang Yu, Cong Chen, Tingzi Hu, Haiping Yang, Fuming He","doi":"10.1007/s00056-024-00533-2","DOIUrl":"https://doi.org/10.1007/s00056-024-00533-2","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this cross-sectional study was to use multiple regression analysis to evaluate the relationship between the mandibular curve of Spee (COS) and the maxillary compensating curve with dentoskeletal morphology in young Chinese adults with normal occlusion.</p><p><strong>Methods: </strong>This study comprised 62 young adults (31 males, mean age: 24.1 ± 2.2 years; 31 females, mean age: 23.3 ± 3.3 years) with Angle class I normal occlusion. For every subject, intraoral scan models of the maxillary and mandibular arches and lateral cephalograms were acquired. The depth of the COS and compensating curve were assessed on the intraoral scan models. Multiple dental arch dimensional and cephalometric variables were screened by univariate analysis. Subsequently, a multiple linear regression model (forward stepwise selection) was constructed to determine which variables were significantly correlated with the two curve depths.</p><p><strong>Results: </strong>In the mandible, the COS depth was deepest at the mesiobuccal cusp of the first molar. Overjet, mandibular arch width and mandibular-occlusal plane angle significantly correlated with the COS depth (P < 0.05), accounting for 33.1% of the variation in the mandibular COS. In the maxilla, the deepest point of the compensating curve was at the distobuccal cusp of the first molar. Mandibular arch perimeter and overbite significantly correlated with the maxillary compensating curve (P < 0.05), explaining 23.3% of the variation.</p><p><strong>Conclusions: </strong>Overjet, overbite, mandibular-occlusal plane angle, mandibular arch width and perimeter should be considered when reconstructing occlusal curves in clinical orthodontic treatment and in prosthetic restoration.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141443702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to: Frequency and variability of nonmetric dental crown traits of primary and permanent molars in a group of orthodontic patients.","authors":"Ariane Beatriz Blancato, Eva Paddenberg-Schubert, Peter Proff, Maria Angélica Hueb de Menezes-Oliveira, Svenja Beisel-Memmert, Flares Baratto-Filho, Carsten Lippold, Christian Kirschneck, Erika Calvano Küchler, César Penazzo Lepri","doi":"10.1007/s00056-024-00538-x","DOIUrl":"10.1007/s00056-024-00538-x","url":null,"abstract":"","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141428349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frequency and variability of nonmetric dental crown traits of primary and permanent molars in a group of orthodontic patients.","authors":"Ariane Beatriz Blancato, Eva Paddenberg-Schubert, Peter Proff, Maria Angélica Hueb de Menezes-Oliveira, Svenja Beisel-Memmert, Flares Baratto-Filho, Carsten Lippold, Christian Kirschneck, Erika Calvano Küchler, Cesar Penazzo Lepri","doi":"10.1007/s00056-024-00532-3","DOIUrl":"10.1007/s00056-024-00532-3","url":null,"abstract":"<p><strong>Background: </strong>The present study aimed to assess the frequency and variation of 13 nonmetric dental crown traits (NDCT) in permanent and primary molars in German orthodontic patients.</p><p><strong>Methods: </strong>Dental records from orthodontic patients were screened and evaluated. First and second permanent and primary upper and lower molars (from left and right sides) were assessed. Teeth with cavitated dental caries, occlusal wear, restorations and obvious dental deformities were not evaluated. The NDCT for permanent molars were identified and scored according to the odontoscopic system developed by Arizona State University Dental Anthropology System (ASUDAS). The NDCT for primary molars were identified and scored according to ASUDAS, Hanihara's method and Sciulli's method. The χ² test was used to investigate side preference and sexual dimorphism at a significance level of p ≤ 0.050.</p><p><strong>Results: </strong>A total of 163 orthodontic patients (82 males and 81 females) aged 8-14 years were included. A sexual dimorphism was observed for the hypocone in first upper permanent molar (p = 0.041). The protostylid was observed in lower permanent molars (range 2.1-10%). Males presented more hypoconulid than females (p = 0.019). Only females presented the distal trigonid crest in lower first permanent molars (p = 0.002). The most common groove pattern in primary molars was Y; male presented more Y grade than females in the lower second primary molar (p = 0.039). Asymmetry was observed in some traits, ranging from 0 to 100%.</p><p><strong>Conclusion: </strong>The present study showed the frequency of NDCT of molars in German orthodontic patients and demonstrated that some traits present sexual dimorphism.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141262972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of low-level laser therapy on en masse retraction in females with bimaxillary dentoalveolar protrusion : A single-center randomized clinical trial.","authors":"Heba Mohamed Dehis, Fouad Aly El Sharaby, Faten Husain Eid, Yehya Ahmed Mostafa","doi":"10.1007/s00056-024-00525-2","DOIUrl":"https://doi.org/10.1007/s00056-024-00525-2","url":null,"abstract":"<p><strong>Background: </strong>Acceleration of tooth movement has gained remarkable attention during the last decade. The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on en masse retraction of upper anterior teeth in adult women with bimaxillary dentoalveolar protrusion.</p><p><strong>Materials and methods: </strong>In this two-arm parallel trial, 36 women with bimaxillary dentoalveolar protrusion were randomly divided into two equal groups. Eligibility criteria included class I Angle molar relationship, good general and oral health as well as no systemic disease or syndrome. Four temporary anchorage devices (TADs) were used in the upper and lower arches for anchorage purposes. A 0.019×0.025-inch stainless steel wire with crimped hooks just distal to the maxillary canines was inserted. Nickle titanium (NiTi) closed coil springs (200 g/side) were employed for en masse retraction following extraction of the first premolars. In the laser group (LG), retraction of the upper anterior teeth was done along with the application of LLLT on days 0, 3, 7, and 14 after extraction and then repeated biweekly until the end of retraction. Retraction was completed without LLLT application in the nonlaser group (NLG). Data concerning the rate of retraction as well as first molars and anterior positional changes were gained from digitized models and cone beam computed tomography (CBCT) scans taken just before extraction and at the end of retraction. Treatment-associated pain and root resorption were evaluated using visual analogue scale (VAS) and CBCT scans, respectively.</p><p><strong>Results: </strong>Four patients dropped out prior to follow-up. The duration of retraction was 10.125 ± 2.876 and 13.643 ± 3.455 months in the LG and NLG, respectively. The LG showed a statistically significant faster rate of en masse retraction (0.833 ± 0.371 mm/month) compared to the NLG (0.526 ± 0.268 mm/month; P ≤ 0.035). The observed root resorption was significantly less in the LG (P ≤ 0.05) with comparable pain scores in both groups.</p><p><strong>Conclusions: </strong>Within the constraints of the parameters of the LLLT used in the current study and despite the statistically significant results on the rate of en masse retraction and the associated root resorption, LLLT did not demonstrate a clinically relevant effect that justifies its use to enhance en masse retraction.</p><p><strong>Name of the registry: </strong>Clinicaltrials.gov TRIAL REGISTRATION NUMBER: NCT05183451 DATE OF REGISTRATION: January 10, 2022, \"Retrospectively registered\" URL OF TRIAL REGISTRY RECORD: https://www.</p><p><strong>Clinicaltrials: </strong>gov/study/NCT05183451.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141262865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical implications of a mathematical-geometrical model to predict changes in the anterior arch dimension.","authors":"Eva Paddenberg-Schubert, Raphael Heiß, Tobias Grünbaum, Peter Proff, Christian Kirschneck","doi":"10.1007/s00056-024-00531-4","DOIUrl":"https://doi.org/10.1007/s00056-024-00531-4","url":null,"abstract":"<p><strong>Purpose: </strong>Anterior arch length (AL) and the alterations in its dimension following incisor movements were shown to be predictable for an individual patient using a mathematical-geometrical model based on a third-degree parabola. Although the model has been validated previously, it is hard to apply in daily orthodontic routine. Thus, the aim of this study was to modify the model using different approaches to allow its establishment in daily routine.</p><p><strong>Methods: </strong>This retrospective study was based on a study collective, which was described previously and consisted of 50 randomly chosen dental casts and lateral cephalograms taken before (T0) and after (T1) orthodontic treatment with fixed appliances. A JAVA computer program (Oracle, Austin, TX, USA) was developed to predict AL changes following therapeutic changes of arch width, depth or incisor inclination/position, taking the type of tooth movement into account. Performing exemplary AL calculations with the computer program, general rules and nomograms were set up, followed by multiple linear regression analyses to establish easy-to-use regression equations.</p><p><strong>Results: </strong>The JAVA computer program is available for download. Sagittal changes showed more effect on AL than transverse modifications. Protruding incisors increased AL, but also reduced overbite. The extent of alteration in AL depended on the initial depth, width, incisor inclination, tooth movement type and distance between the incisal edge and the centre of rotation.</p><p><strong>Conclusions: </strong>The computer program precisely predicts individual changes in AL but is time-consuming. The presented regression equations and nomograms, considering metric variables, are easier to apply clinically and the differences compared to the AL calculated by the computer program are negligible.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141162841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of micro-osteoperforations (MOPs) on the rate of en masse orthodontic tooth retraction : A randomized controlled trial.","authors":"Prashant Kumar, Abdulqadir H Rampurawala, Amol S Patil","doi":"10.1007/s00056-022-00420-8","DOIUrl":"10.1007/s00056-022-00420-8","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the effect of micro-osteoperforations (MOPs) on the rate of orthodontic tooth movement (OTM) during en masse anterior retraction.</p><p><strong>Materials and methods: </strong>Twenty patients were randomly allocated into experimental and control group of 10 each. In the control group, en masse retraction was performed with sliding mechanics with a coil spring. In the experimental group after alignment and levelling, MOPs were performed mesially and distally to all six anterior teeth in the interdental cortical region on the labial aspect of both arches. MOPs were performed at the beginning of space closure (T₀) and 1 month after beginning of space closure (T₁). En masse retraction was performed with sliding mechanics with a coil spring. Measurements were recorded on digital models made from scanned plaster casts at the beginning of space closure (T₀) and monthly at each follow-up visit for the next 4 months (T₁, T₂, T₃, T₄). The monthly rate of OTM, the overall rate of OTM, and the difference between OTM in the MOP period (T₀-T₂) and post-MOP (T₂-T₄) period in the experimental and control group were evaluated. A visual analogue scale (VAS) was used to evaluate patients' pain experience.</p><p><strong>Results: </strong>The overall rate of OTM was significantly greater in the experimental group for both arches in the MOP period (T₀-T₂) and also in the post-MOP period (T₂-T₄) as compared to the control group. Within the experimental group, the rate of OTM in the MOP period was significantly greater than in the post-MOP period, which in turn was greater than that of the control group. The patients reported only mild discomfort for 24 h after performing the MOPs, which then gradually decreased.</p><p><strong>Conclusions: </strong>The use of MOPs is effective in increasing the rate of en masse tooth retraction in both the maxillary and the mandibular arch. The rate of tooth movement was greater even in the post-MOP period as compared to the control group.</p>","PeriodicalId":54776,"journal":{"name":"Journal of Orofacial Orthopedics-Fortschritte Der Kieferorthopadie","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33439743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}