Korean Journal of Orthodontics最新文献

{"title":"Distribution, side involvement, phenotype and associated anomalies of Korean patients with craniofacial clefts from single university hospitalbased data obtained during 1998-2018.","authors":"Jee Hyeok Chung,&nbsp;Sunjin Yim,&nbsp;Il-Sik Cho,&nbsp;Seung-Weon Lim,&nbsp;Il-Hyung Yang,&nbsp;Jeong Hyun Ha,&nbsp;Sukwha Kim,&nbsp;Seung-Hak Baek","doi":"10.4041/kjod.2020.50.6.383","DOIUrl":"10.4041/kjod.2020.50.6.383","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the distribution, side involvement, phenotype, and associated anomalies of Korean patients with craniofacial clefts (CFC).</p><p><strong>Methods: </strong>The samples consisted of 38 CFC patients, who were treated at Seoul National University Dental Hospital during 1998-2018. The Tessier cleft type, sex, side involvement, phenotype, and associated anomalies were investigated using nonparametric statistical analysis.</p><p><strong>Results: </strong>The three most common types were #7 cleft, followed by #0 cleft and #14 cleft. There was no difference between the frequency of male and female. Patients with #0 cleft exhibited nasal deformity, bony defect, and missing teeth in the premaxilla, midline cleft lip, and eye problems. A patient with #3 cleft (unilateral type) exhibited bilateral cleft lip and alveolus. All patients with #4 cleft were the bilateral type, including a combination of #3 and #4 clefts, and had multiple missing teeth. A patient with #5 cleft (unilateral type) had a posterior openbite. In patients with #7 cleft, the unilateral type was more prevalent than the bilateral type (87.0% vs. 13.0%, p < 0.001). Sixteen patients showed hemifacial microsomia (HFM), Goldenhar syndrome, and unilateral cleft lip and palate (UCLP). There was a significant match in the side involvement of #7 cleft and HFM (87.5%, <i>p</i> < 0.01). Patients with #14 cleft had plagiocephaly, UCLP, or hyperterorbitism. A patient with #30 cleft exhibited tongue tie and missing tooth.</p><p><strong>Conclusions: </strong>Due to the diverse associated craniofacial anomalies in patients with CFC, a multidisciplinary approach involving a well-experienced cooperative team is mandatory for these patients.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 6","pages":"383-390"},"PeriodicalIF":1.9,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f7/8d/KJOD-50-383.PMC7642224.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38667550","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":"Characterization of dental phenotypes and treatment modalities in Korean patients with Parry-Romberg syndrome.","authors":"Sunjin Yim,&nbsp;Il-Hyung Yang,&nbsp;Seung-Hak Baek","doi":"10.4041/kjod.2020.50.6.407","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.6.407","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the dental phenotypes and treatment modalities (Tx- Mod) in Korean patients with Parry-Romberg syndrome (PRS) using longitudinal data.</p><p><strong>Methods: </strong>The samples consisted of 10 PRS patients, who were treated and/or followed-up at Seoul National University Dental Hospital between 1998 and 2019. Using a novel PRS severity index based on the numbers of the atrophy-involved area and asymmetry-involved item, we classified them into mild (n = 3), moderate (n = 2), and severe (n = 5). Dental phenotypes, including congenitally missing tooth (Con-Missing-Tooth), microdontia, tooth with short root (Short-Root), tooth with dilacerated root, and delayed eruption/impacted tooth, were investigated along with Tx-Mod.</p><p><strong>Results: </strong>The side of occurrence of all dental phenotypes showed 100% concordance with the side of PRS involvement. The most two common dental phenotypes were Con-Missing- Tooth and Short-Root (n = 29 and n = 17 in six patients). The sums of the average number of Con-Missing-Tooth and Short-Root increased from mild PRS to moderate PRS and severe PRS cases (1.0, 6.0, and 6.2). In terms of Tx- Mod, growth observation due to mild atrophy, fixed orthodontic treatment, and grafting were used for mild PRS cases. Tx-Mod for moderate PRS cases involved growth observation for surgery due to an early age at the initial visit. For severe PRS cases, diverse Tx-Mod combinations including unilateral functional appliance, fixed orthodontic treatment, growth observation, grafting, and orthognathic surgery were used.</p><p><strong>Conclusions: </strong>The novel PRS severity index may be useful to provide primary data for individualized diagnosis and treatment planning for PRS patients.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 6","pages":"407-417"},"PeriodicalIF":1.9,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f5/bd/KJOD-50-407.PMC7642227.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38667553","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":"Stability of bimaxillary surgery involving intraoral vertical ramus osteotomy with or without presurgical miniscrew-assisted rapid palatal expansion in adult patients with skeletal Class III malocclusion.","authors":"Yoon-Soo Ahn,&nbsp;Sung-Hwan Choi,&nbsp;Kee-Joon Lee,&nbsp;Young-Soo Jung,&nbsp;Hyoung-Seon Baik,&nbsp;Hyung-Seog Yu","doi":"10.4041/kjod.2020.50.5.304","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.304","url":null,"abstract":"<p><strong>Objective: </strong>The aim of this study was to evaluate the stability of bimaxillary surgery involving bilateral intraoral vertical ramus osteotomy performed with or without presurgical miniscrew-assisted rapid palatal expansion (MARPE) in adult patients with skeletal Class III malocclusion.</p><p><strong>Methods: </strong>A total of 40 adult patients with skeletal Class III malocclusion were retrospectively divided into two groups (n = 20 each) according to the use of MARPE for the correction of transverse maxillomandibular discrepancy during presurgical orthodontic treatment. Serial lateral cephalograms and dental casts were analyzed until 6 months after surgery.</p><p><strong>Results: </strong>Before presurgical orthodontic treatment, there was no significant differences in terms of sex and age between groups. However, the difference of approximately 3.1 mm in the maxillomandibular intermolar width was statistically significant (<i>p</i> < 0.001). Two days after surgery, the mandible had moved backward and upward without any significant intergroup difference. Six months after surgery, the maxillary intercanine (2.7 ± 2.1 mm), interpremolar (3.6 ± 2.4 mm), and intermolar (2.0 ± 1.3 mm) arch widths were significantly increased (<i>p</i> < 0.001) relative to the values before presurgical orthodontic treatment in the MARPE group; these widths were maintained or decreased in the control group. However, there was no significant difference in surgical changes and the postsurgical stability between the two groups. No significant correlations existed between the amount of maxillary expansion and postsurgical mandibular movement.</p><p><strong>Conclusions: </strong>MARPE is useful for stable and nonsurgical expansion of the maxilla in adult patients with skeletal Class III malocclusion who are scheduled for bimaxillary surgery.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"304-313"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/2e/e7/KJOD-50-304.PMC7500573.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38387410","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":"Treatment modalities for Korean patients with unilateral hemifacial microsomia according to Pruzansky-Kaban types and growth stages.","authors":"Il-Hyung Yang,&nbsp;Jee Hyeok Chung,&nbsp;Sunjin Yim,&nbsp;Il-Sik Cho,&nbsp;Sukwha Kim,&nbsp;Jin-Young Choi,&nbsp;Jong-Ho Lee,&nbsp;Myung-Jin Kim,&nbsp;Seung-Hak Baek","doi":"10.4041/kjod.2020.50.5.336","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.336","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the treatment modalities (Tx-Mods) for patients with unilateral hemifacial microsomia (UHFM) according to Pruzansky-Kaban types and growth stages.</p><p><strong>Methods: </strong>The samples consisted of 82 Korean UHFM patients. Tx-Mods were defined as follows: Tx-Mod-1, growth observation due to mild facial asymmetry; Tx-Mod-2, unilateral functional appliance; Tx- Mod-3, fixed orthodontic treatment; Tx-Mod-4, growth observation due to a definite need for surgical intervention; Tx-Mod-5, unilateral mandibular or bimaxillary distraction osteogenesis (DO); Tx-Mod-6, maxillary fixation using LeFort I osteotomy and mandibular DO/sagittal split ramus osteotomy; Tx- Mod-7, orthognathic surgery; and Tx-Mod-8, costochondral grafting. The type and frequency of Tx-Mod, the number of patients who underwent surgical procedures, and the number of surgeries that each patient underwent, were investigated.</p><p><strong>Results: </strong>The degree of invasiveness and complexity of Tx-Mod increased, with an increase in treatment stage and Pruzansky-Kaban type (initial < final; [I, IIa] < [IIb, III], all <i>p</i> < 0.001). The percentage of patients who underwent surgical procedures increased up to 4.2 times, with an increase in the Pruzansky-Kaban type (I, 24.1%; IIa, 47.1%; IIb, 84.4%; III, 100%; <i>p</i> < 0.001). However, the mean number of surgical procedures that each patient underwent showed a tendency of increase according to the Pruzansky-Kaban types (I, n = 1.1; IIa, n = 1.5; IIb, n = 1.6; III, n = 2.3; <i>p</i> > 0.05).</p><p><strong>Conclusions: </strong>These findings might be used as basic guidelines for successful treatment planning and prognosis prediction in UHFM patients.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"336-345"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/84/e4/KJOD-50-336.PMC7500569.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38388228","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":"HeeJin Lim","doi":"10.4041/kjod.2020.50.5.291","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.291","url":null,"abstract":"","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"291-292"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/10/d7/KJOD-50-291.PMC7500572.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38387407","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":"Three-dimensional surgical accuracy between virtually planned and actual surgical movements of the maxilla in two-jaw orthognathic surgery.","authors":"Mihee Hong,&nbsp;Myung-Jin Kim,&nbsp;Hye Jung Shin,&nbsp;Heon Jae Cho,&nbsp;Seung-Hak Baek","doi":"10.4041/kjod.2020.50.5.293","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.293","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the three-dimensional (3D) surgical accuracy between virtually planned and actual surgical movements (SM) of the maxilla in twojaw orthognathic surgery.</p><p><strong>Methods: </strong>The sample consisted of 15 skeletal Class III patients who underwent two-jaw orthognathic surgery performed by a single surgeon using a virtual surgical simulation (VSS) software. The 3D cone-beam computed tomography (CBCT) images were obtained before (T0) and after surgery (T1). After merging the dental cast image onto the T0 CBCT image, VSS was performed. SM were classified into midline correction (anterior and posterior), advancement, setback, anterior elongation, and impaction (total and posterior). The landmarks were the midpoint between the central incisors, the mesiobuccal cusp tip (MBCT) of both first molars, and the midpoint of the two MBCTs. The amount and direction of SM by VSS and actual surgery were measured using 3D coordinates of the landmarks. Discrepancies less than 1 mm between VSS and T1 landmarks indicated a precise outcome. The surgical achievement percentage (SAP, [amount of movement in actual surgery/ amount of movement in VSS] × 100) (%) and precision percentage (PP, [number of patients with precise outcome/number of total patients] × 100) (%) were compared among SM types using Fisher's exact and Kruskal-Wallis tests.</p><p><strong>Results: </strong>Overall mean discrepancy between VSS and actual surgery, SAP, and PP were 0.13 mm, 89.9%, and 68.3%, respectively. There was no significant difference in the SAP and PP values among the seven SM types (all <i>p</i> > 0.05).</p><p><strong>Conclusions: </strong>VSS could be considered as an effective tool for increasing surgical accuracy.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"293-303"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/59/41/KJOD-50-293.PMC7500567.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38387409","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":"Positional changes in the mandibular proximal segment after intraoral vertical ramus osteotomy: Surgery-first approach versus conventional approach.","authors":"Seoyeon Jung,&nbsp;Yunjin Choi,&nbsp;Jung-Hyun Park,&nbsp;Young-Soo Jung,&nbsp;Hyoung-Seon Baik","doi":"10.4041/kjod.2020.50.5.324","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.324","url":null,"abstract":"<p><strong>Objective: </strong>To compare postoperative positional changes in the mandibular proximal segment between the conventional orthognathic surgery (CS) and the surgery-first approach (SF) using intraoral vertical ramus osteotomy (IVRO) in patients with Class III malocclusion.</p><p><strong>Methods: </strong>Thirty-eight patients with skeletal Class III malocclusion who underwent bimaxillary surgery were divided into two groups according to the use of preoperative orthodontic treatment: CS group (n = 18) and SF group (n = 20). Skeletal changes in both groups were measured using computed tomography before (T0), 2 days after (T1), and 1 year after (T2) the surgery. Three-dimensional (3D) angular changes in the mandibular proximal segment, condylar position, and maxillomandibular landmarks were assessed.</p><p><strong>Results: </strong>The mean amounts of mandibular setback and maxillary posterior impaction were similar in both groups. At T2, the posterior portion of the mandible moved upward in both groups. In the SF group, the anterior portion of the mandible moved upward by a mean distance of 0.9 ± 1.0 mm, which was statistically significant (<i>p</i> < 0.001). There were significant between-group differences in occlusal changes (<i>p</i> < 0.001) as well as in overjet and overbite. However, there were no significant between-group differences in proximal segment variables.</p><p><strong>Conclusions: </strong>Despite postoperative occlusal changes, positional changes in the mandibular proximal segment and the position of the condyles were similar between CS and SF, which suggested that SF using IVRO achieved satisfactory postoperative stability. If active physiotherapy is conducted, the proximal segment can be adapted in the physiological position regardless of the occlusal changes.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"324-335"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ec/f3/KJOD-50-324.PMC7500571.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38388227","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":"Maxillary protraction using customized mini-plates for anchorage in an adolescent girl with skeletal Class III malocclusion.","authors":"Shuran Liang,&nbsp;Xianju Xie,&nbsp;Fan Wang,&nbsp;Qiao Chang,&nbsp;Hongmei Wang,&nbsp;Yuxing Bai","doi":"10.4041/kjod.2020.50.5.346","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.346","url":null,"abstract":"<p><p>The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized miniplates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400-500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"346-355"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/32/0f/KJOD-50-346.PMC7500574.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38388229","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":"The six geometries revisited.","authors":"Austin Kang,&nbsp;Marino Musilli,&nbsp;Mauro Farella","doi":"10.4041/kjod.2020.50.5.356","DOIUrl":"https://doi.org/10.4041/kjod.2020.50.5.356","url":null,"abstract":"<p><p>Forces and moments delivered by a straight wire connecting two orthodontic brackets are statically indeterminate and cannot be estimated using the classical equations of static equilibrium. To identify the mechanics of such two-bracket systems, Burstone and Koenig used the principles of linear beam theory to estimate the resulting force systems. In the original publication, however, it remains unclear how the force systems were calculated because no reference or computational details on the underlying principles have been provided. Using the moment carry-over principle and the relative angulation of the brackets, a formula was derived to calculate the relative moments of the two brackets. Because of the moment equilibrium, the vertical forces that exist as a forcecouple on the two brackets can also be calculated. The accuracy of the proposed approach can be validated using previously published empirical data.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"356-359"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/a7/a7/KJOD-50-356.PMC7500568.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38388230","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":"Short-term treatment effects produced by rapid maxillary expansion evaluated with computed tomography: A systematic review with meta-analysis.","authors":"Antonino Lo Giudice, Paola Spinuzza, Lorenzo Rustico, Gabriele Messina, Riccardo Nucera","doi":"10.4041/kjod.2020.50.5.314","DOIUrl":"10.4041/kjod.2020.50.5.314","url":null,"abstract":"<p><strong>Objective: </strong>To identify the available evidence on the effects of rapid maxillary expansion (RME) with three-dimensional imaging and provide meta-analytic data from studies assessing the outcomes using computed tomography.</p><p><strong>Methods: </strong>Eleven electronic databases were searched, and prospective case series were selected. Two authors screened all titles and abstracts and assessed full texts of the remaining articles. Seventeen case series were included in the quantitative synthesis. Seven outcomes were investigated: nasal cavity width, maxillary basal bone width, alveolar buccal crest width, alveolar palatal crest width, inter-molar crown width, inter-molar root apex width, and buccopalatal molar inclination. The outcomes were investigated at two-time points: postexpansion (2-6 weeks) and post-retention (4-8 months). Mean differences and 95% confidence intervals were used to summarize and combine the data.</p><p><strong>Results: </strong>All the investigated outcomes showed significant differences postexpansion (maxillary basal bone width, +2.46 mm; nasal cavity width, +1.95 mm; alveolar buccal crest width, +3.90 mm; alveolar palatal crest width, +3.09 mm; intermolar crown width, +5.69 mm; inter-molar root apex width, +2.85 mm; and dental tipping, +3.75°) and post-retention (maxillary basal bone width, +2.21 mm; nasal cavity width, +1.55 mm; alveolar buccal crest width, +3.57 mm; alveolar palatal crest width, +3.32 mm; inter-molar crown width, +5.43 mm; inter-molar root apex width, +4.75 mm; and dental tipping, 2.22°) compared to pre-expansion.</p><p><strong>Conclusions: </strong>After RME, skeletal expansion of the nasomaxillary complex was greater in most caudal structures. Maxillary basal bone showed 10% post-retention relapse. During retention period, uprighting of maxillary molars occurred.</p>","PeriodicalId":49934,"journal":{"name":"Korean Journal of Orthodontics","volume":"50 5","pages":"314-323"},"PeriodicalIF":1.9,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/62/3f/KJOD-50-314.PMC7500570.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38388226","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}