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The purpose of this study was to compare speech outcomes in patients with submucous cleft palate (SMCP) between speech therapy alone and double-opposing Z-plasty (DOZ) combined with speech therapy. The subjects were 67 patients with SMCP (overt type, 45 males, 22 females), who were divided into the observation group (n=18), the speech therapy group (n=24; duration, 17.8 mo), and the DOZ and speech therapy (DOZ-speech therapy) group (n=25; median age at DOZ, 5.3 years, duration, 18.6 mo). The median age at initial and final speech assessments were 3 and 5 years. After age, sex, syndromic status, duration of speech therapy, surgery timing, and speech outcomes were investigated, statistical analysis was performed. After tailored interventions, both isolated and non-isolated SMCP patients experienced significant improvements in speech outcomes, including nasal emission, hypernasality, compensatory articulation, and unintelligible speech. Since comparable improvements were observed, there were no significant differences in the final assessments regardless of initial speech issues between the speech therapy group and the DOZ-speech therapy group (all P>0.05). In the DOZ-speech therapy group, the rate of achieving "socially acceptable" speech was 92.3% in isolated cases and 90% in non-isolated cases. Multivariate analysis revealed that DOZ showed a tendency to reduce hypernasality, compensatory articulation, and "unintelligible" speech; syndromic or developmental conditions influenced outcomes in nasal emission and hypernasality; and initial hypernasality and compensatory articulation were correlated with outcomes. Therefore, DOZ surgery could be recommended to resolve hypernasality and compensatory articulation in SMCP patients before speech issues worsen., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by Mutaz B. Habal, MD.)

Objective: To investigate the growth patterns of the maxillomandibular complex in preadolescent patients with Pierre-Robin sequence (PRS)., Methods: The samples consisted of 20 preadolescent PRS patients who had cleft palate and did not undergo growth-modification therapy or surgical intervention [6 boys and 14 girls; mean age of lateral cephalograms taken, 8.8 y (T1) and 13.7 y (T2)]. According to k-means cluster analysis, four clusters were defined over 3 major groups at T1: (1) Both very retrusive maxilla and mandible group: Cluster-4 [n=4, very large gonial angle, very low facial height ratio (FHR)] and Cluster-1 (n=5, small gonial angle, normal FHR); (2) Retrusive maxilla and very retrusive mandible group (Cluster-3, n=7, normal gonial angle, very low FHR); and (3) Both normal maxilla and mandible group (Cluster-2, n=4, very large gonial angle, low FHR). Seven angular and ratio variables [sella-nasion-A point (SNA), sella-nasion-B point (SNB), A point-nasion-B point (ANB), saddle angle, gonial angle, mandibular-body-length/anterior-cranial-base-length (MBL/ACBL), and FHR] at T1 and T2 and growth change from T1 to T2 were investigated., Results: At T1, SNA, SNB, saddle angle, gonial angle (all P<0.05), and FHR (P<0.01) showed significant difference among 4 clusters. At T2, SNA, SNB and gonial angle (all P<0.05) still showed significant difference among 4 clusters. During T1 to T2, there was no significant change in variables at each cluster except an increase in MBL/ACBL in Cluster-1 and FHR in Cluster-3 (all P<0.05)., Conclusions: Preadolescent PRS patients exhibited diverse skeletal phenotypes at T1, which did not change significantly from their original skeletal patterns by growth during T1 to T2., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by Mutaz B. Habal, MD.)

The purpose of this study was to characterize the spheno-occipital synchondrosis fusion (SOSF) from preadolescents to young adults. A total of 630 Korean subjects (308 men, 322 women; age range, 6-18 y) were divided into 26 groups according to sex and age. After 3-dimensional computed tomography (CT) images were reoriented using the Frankfort horizontal (FH) plane, mid-sagittal plane, and frontal plane via ON3D software (3DONS), the cervical vertebrae maturation index (CVMI) and SOSF stages were identified using 6-stage and 5-stage scoring systems, respectively. The distributions of stage in each group were statistically investigated. Women showed early appearance and a short range of onset (CVMI stage 2, SOSF stage 2), middle (CVMI stage 4, SOSF stage 3 and stage 4), and completion (CVMI stage 6, SOSF stage 5), indicating rapid skeletal maturation compared with men. In both males and females, there were strong positive correlations between age and CVMI stage ( rs =0.902, rs =0.890), between age and SOSF stage ( rs =0.887, rs =0.885), and between CVMI and SOSF stages ( rs =0.955, rs =0.964) (all P <0.001). The mean ages at SOSF stage 3 and stage 4 (12.7~13.9 y in males and 11.0~12.5 y in females) could be used as indicators of the pubertal growth peak. Regression equations for SOSF stage (y), age (a), and CVMI stage (b) were as follows: y=1.355-(0.133×a)+(0.29007×b)+(0.041×a×b) for males ( r2 =0.9496); y=1.305-(0.158×a)+(0.455×b)+(0.036×a×b) for females ( r2 =0.9606). Ordinal logistic regression analyses with the proportional odds model showed that females had more advanced SOSF stages than males (odds ratio: 1.972; 95% CI: 1.063-3.658, P <0.05). Our findings may provide basic references for CVMI and SOSF from preadolescents to young adults., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Contouring surgery is an operation that makes a smooth, oval-shaped face by removing protruding parts of the face. In particular, mandibuloplasty is a procedure that softens the shape of the mandible and is a popular procedure among Asians with a dominant mesocephalic profile. In this study, we tried to discuss the considerations before surgery by dividing the mandibular shape into morphologic aspects in the lateral and frontal views and anatomic considerations. In the lateral view, it is essential to consider the posterior ramal height and mandibular body length of each patient. These factors are closely related to the postoperative outcomes. Consideration of the mandibular plane angle is also essential. In the frontal view, the position of the gonial angle relative to the ramal body should be considered because the position of the gonial angle can affect the difficulty of operation. Anatomic considerations include antero-posterior ramal width, bucco-lingual width of mandibular body, amount of mouth opening, and location of inferior alveolar nerve. These are important factors that determine the difficulty of the operation. In this study, classification according to the shape and shape of the mandible was presented, and considerations for each classification were discussed. Cosmetic surgery is a socio-psychologically meaningful procedure that not only improves the esthetics but also improves the mental well-being of the patients. Therefore, it will be possible to provide better medical services to patients if clinicians are fully aware of the factors that can increase the difficulty of the operation and the factors that affect the surgical outcome., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

The purpose of this study was to classify the skeletal phenotypes of adult patients with skeletal class III (C-III) malocclusion and unilateral or bilateral cleft lip and palate using principal component analysis and cluster analysis. The samples consisted of 81 adult C-III patients with cleft lip and palate (CLP) who underwent orthognathic surgery (OGS) or distraction osteogenesis (59 males and 22 females; 50 unilateral cleft lip and palate and 31 bilateral cleft lip and palate; mean age when lateral cephalograms were taken, 22.2±4.6 y). Thirteen angular and one ratio cephalometric variables were measured. Using 4 representative variables obtained from principal component analysis (SNA, SNB, Gonial angle, and Bjork sum), K-means cluster analysis was performed to classify the phenotypes. Then, statistical analysis was conducted to characterize the differences in the variables among the clusters. Five clusters were obtained from 3 groups: severely retrusive maxilla and moderately retrusive mandible group: cluster-1 (23.5%, severely hyperdivergent pattern), cluster-4 (27.2%, moderately hyperdivergent pattern), and cluster-5 (11.1%, normodivergent pattern); moderately retrusive maxilla and normal mandible group: cluster-2 (30.9%, normodivergent pattern); normal maxilla and moderately protrusive mandible group: cluster-3 (7.4%, normodivergent pattern). Although skeletal phenotypes were diverse, distribution of sex and cleft type did not differ among 5 clusters ( P >0.05). Sixty-two percent of cleft patients showed a severely retrusive maxilla and moderately retrusive mandible (cluster-1, cluster-4, and cluster-5), which indicated that these are the main cause of skeletal C-III malocclusion in CLP patients who were treated with OGS. Therefore, it is necessary to consider presurgical orthodontic treatment and surgical planning based on the skeletal phenotypes of CLP patients., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

This study aimed to classify the skeletal phenotypes of preadolescent patients with isolated cleft palate using principal component analysis and cluster analysis. Sixty-four preadolescent female patients with isolated cleft palate (incomplete hard palate and complete soft palate cleft group, n=51; complete cleft of the hard and soft palate group, n=13; the mean age when lateral cephalograms were taken, 7.08±0.76 y) were included. Ten angular and 2 ratio cephalometric variables were measured on a lateral cephalogram. Cluster analysis was performed using 3 representative variables obtained from principal component analysis (SN-GoMe, SNA, and SNB). The differences in the variables among the clusters were characterized using the Kruskal-Wallis test. As a result of the analysis, 6 clusters were obtained from 3 groups: the retrusive maxilla and mandible group: cluster 3 (14.1%, moderately hyperdivergent pattern), cluster 5 (17.2%, severely hyperdivergent pattern); the normal maxilla and mandible group: cluster 1 (23.4%, normodivergent pattern), cluster 4 (12.5%, moderately hyperdivergent pattern), cluster 6 (20.3%, severely hyperdivergent pattern); the normal maxilla and protrusive mandible group: cluster 2 (12.5%, normodivergent pattern). The distribution of isolated cleft palate types did not differ among the 6 clusters ( P >0.05). Two thirds of the patients (68.7%, clusters 1, 2, 4, and 6) had a normal anteroposterior position of the maxilla, while one third of the patients (31.3%, clusters 3 and 5) showed a retrusive mandible. These results indicate that isolated cleft palate patients have diverse maxillo-mandibular growth patterns compared with patients with cleft lip and palate., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

The purpose of this study was to investigate the distribution and phenotype of Goldenhar syndrome (GS) and its association with other anomalies. The samples consisted of 18 GS patients (6 males and 12 females; mean age at investigation, 7.4 ± 4.8 y) who were treated or followed up at the Department of Orthodontics, Seoul National University Dental Hospital between 1999 and 2021. The prevalence of side involvement and degree of mandibular deformity (MD), midface anomalies, and association with other anomalies were evaluated using statistical analysis. The prevalence of unilateral and bilateral MD did not differ (55.6% versus 44.4%). In unilateral MD cases, there was a tendency for higher prevalence of more severe Pruzansky-Kaban types than mild ones (type I, 10%; type IIa, 10%; type IIb, 50%; type III, 30%). Despite hypoplasia of the condyle/ramus complex, compensatory mandibular body growth occurred in 33.3% of GS patients (more severe side in bilateral MD cases, 37.5%, and ipsilateral side in unilateral MD cases, 30%). Class II molar relation was more prevalent than class I and class III molar relations (72.2% versus 11.1% versus 16.7%, P <0.01). Al total of 38.9% of patients had congenitally missing tooth. #7 facial cleft was found in 44.4% of patients. In midface anomalies, ear problem was the most common anomaly, followed by hypoplasia/absence of zygomatic arch and eye problem (88.9% versus 64.3% versus 61.1%, P <0.01). Association with the midface, spine, cardiovascular, and limb anomalies did not differ between unilateral and bilateral MD cases. These results might provide a basic guideline for diagnosis and treatment planning for GS patients., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Facial asymmetry can be defined as differences in the left and right sides of the face, and most of the patients with facial asymmetry have different left and right frontal-ramal inclinations (FRIs). Restoring the symmetry of both FRIs is important in the surgery of facial asymmetry patients, but it is very difficult to achieve perfect symmetry through conventional orthognathic surgery. However, by using 3-dimensional (3D) virtual planning and CAD/CAM technolo gies, intentional change of FRIs can be possible so the symmetry can be improved. The purpose of this study is to evaluate the surgical accuracy and long-term stability of intentional change of FRIs by 3D virtual surgery, CAD/CAM-assisted orthognathic surgery for patients with facial asymmetry. The study included 20 patients who had undergone orthognathic surgery for skeletal class III malocclusion from January 2019 to December 2021. To evaluate the accuracy of surgery, 3D facial cone beam computed tomography (CBCT) taken immediately after surgery (T1) and virtual surgery data (Tv) were measured and the difference values were calculated. The evaluation of the long-term stability of intentional change of FRI was performed by measuring T1 and T2 (3D facial cone beam computed tomography images taken 6 mo after surgery) and the difference values were calculated. The difference values of FRIs in the left and right proximal segments of each patient were calculated. And then, for comparison depending on the direction of rotation, increased FRI groups (n=20, medial rotation) and decreased FRI groups (n=20, lateral rotation) were analyzed separately. As a result, all difference values at both (ΔT1-Tv) and (ΔT2-T1) were <1 degree. As a result of analyzing the entire FRI by dividing it into decreasing and increasing groups, the mean value of (ΔT1-Tv) was 0.225 degrees for the decreasing group and 0.275 degrees for the increasing group. It means that the proximal segment moved less than the movement implemented by the virtual surgery through actual surgery but it shows a very small error, which means that the overall operation almost accurately implements the virtual surgical planning. Compared with (ΔT1-Tv), the mean value of (ΔT2-T1) showed a much smaller error value, and no specific tendency was observed. This indicates that the stability after surgery is very good. Based on this study, using 3D virtual surgery planning and CAD/CAM technologies for treating patients with facial asymmetry was very useful, and surgery could be performed accurately and predictably. In particular, left-right symmetry was almost perfectly achieved through virtual simulation and could be implemented through actual surgery. Therefore, it can be said that the use of these 3D technologies is recommended for the surgical approach of facial asymmetry., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Objective: To investigate the causes of reoperation consultation, and the actual percentage and procedures of reoperation after previous orthognathic surgery., Methods: The samples consisted of 30 patients who visited our clinic for reoperation consultation from October 2015 to September 2021 (6 males and 24 females; mean age at reoperation consultation, 28.4 y). Patient's causes of reoperation consultation were divided into "esthetic dissatisfaction," "airway changes," "temporomandibular disorders," "uncomfortable occlusion," and "other complications". In terms of esthetic dissatisfaction, the more detailed esthetic problem was evaluated by the clinical chart, facial photographs, and radiographs. In patients who actually underwent reoperation, the actual percentage and procedures of reoperation were investigated., Results: The most prevalent causes for reoperation consultation were "esthetic dissatisfaction" (n = 21, 70.0%), followed by "airway changes" (n = 11, 36.7%), "uncomfortable occlusion" (n = 8, 26.7%), "other complications" (n = 5, 16.7%), and "temporomandibular disorder" (n = 4, 13.3%). Less than half of patients actually underwent reoperation (n = 13, 43.3%). Actual reoperation procedures included minor revision surgery, reconstruction surgery, or complete reoperation according to the patient's need. In case of complete reoperation, more accurate and predictable results were obtained by using virtual surgical planning, customized surgical guides, titanium surgical plates made with computer-aided design and computer-aided manufacturing technique, and a 3-dimensional printing method., Conclusion: It is important to communicate with patients about expectations for facial esthetic improvement by orthognathic surgery for obtaining the patient's postoperative satisfaction., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

The purpose of this study was to classify and characterize facial asymmetry (FA) phenotypes in adult patients with unilateral cleft lip and palate (UCLP) and skeletal class III malocclusion. The samples comprised 52 adult UCLP patients (36 men and 16 women; mean age, 22.43 y) who had undergone orthognathic surgery for correction of class III malocclusion. After measurement of 22 cephalometric parameters in posteroanterior cephalograms taken 1 month before orthognathic surgery, principal component analysis was performed to obtain 5 representative parameters [deviation (mm) of ANS (ANS-dev), maxillary central incisor contact point (Mx1-dev), and menton (Me-dev); cant (degree) of the maxillary anterior occlusal plane (MxAntOP-cant) and mandibular border (MnBorder-cant)]. K-means cluster analysis was conducted using these representative parameters. The differences in cephalometric parameters among the clusters were statistically analyzed. The FA phenotypes were classified into 4 types: No-cant-and-No-deviation type (cluster-4, n=16, 30.8%); MxMn-cant-MxMn-dev to the cleft-side type (cluster-3, n=4, 7.7%); Mx-cant-Mn-shift to the cleft-side type (cluster-2, n=15, 28.8%); and Mn-cant-Mn-dev to the noncleft-side type (cluster-1, n=17, 32.7%). Asymmetry in the maxilla and/or mandible were observed in 70% of patients. One third of patients (cluster-2 and cluster-3; sum, 36.5%) exhibited significant cant of MxAntOP induced by cleft and cant or shift of the mandible to the cleft side. Another one third of patients (cluster-1, 32.7%) demonstrated significant deviation and cant of the mandible to the noncleft-side despite cleft in the maxilla. This FA phenotype classification might be a basic guideline for diagnosis and treatment planning for UCLP patients., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Objective: To introduce a guideline for selecting proper surgical modalities for correction of skeletal Class II malocclusion with moderate-to-severe vertical height deficiency (VHD) of the condyle/ramus complex (CRC) using bimaxillary surgery in conjunction with total joint replacement (TJR) or inverted-L osteotomy (ILO) assisted by 3D virtual surgical planning and CAD/CAM technologies., Cases: Four cases of severe skeletal Class II patients with moderate-to-severe VHD of CRC were presented. They underwent bimaxillary surgery using Le Fort I osteotomy in the maxilla and TJR or ILO in the mandible, with the help of virtual surgical planning (VSP) and computer-aided design/computer-aided manufacturing (CAD/CAM)-printed surgical guides and osteosynthesis plates. Guidelines are as follows: (1) if a patient has a moderate degree of VHD and the function of the temporomandibular joint (TMJ) is normal, ILO would be preferred for vertical elongation of the ramus; (2) if a patient has congenitally small condyle or severe condylar resorption, TJR would be preferred to resolve severe VHD of CRC; and (3) when a patient has a metal allergy, foreign body reaction or anatomic limitations (ie, thin cranial base cortex for fossa fixation), ILO would be a better option than TJR., Results: TJR or ILO using VSP and CAD/CAM-printed surgical guides, wafers, and customized plates can provide a proper selection of the surgical plan, accurate transfer of surgical plans to actual surgical procedures, and esthetic improvement of the facial profile., Conclusion: This guideline based on the degree of VHD and functional aspects of CRC might help clinicians to select effective surgical modality for correction of skeletal Class II malocclusion with moderate-to-severe VHD of CRC., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Objective: Maxillomandibular advancement (MMA) is the most effective surgical method for treating obstructive sleep apnea, and it moves the maxillomandibular complex forward to increase the entire upper airway volume. By using 3-dimensional (D) virtual surgery, computer-aided design/computer-aided manufacturing, and 3D printing technologies, it is possible to overcome all the limitations of conventional methods., Materials and Methods: In this study, (modified) MMA was performed by applying 3D technologies to obstructive sleep apnea patients. Virtual surgery was done as surgical plan, cutting guides, and customized plates were made by computer-aided design/computer-aided manufacturing and 3D printing technologies for surgical procedures., Results: After surgery, all patients improved their appearance, quality of sleep, and sleep apnea level were dramatically improved. Through these results, it was found that there are many advantages in using 3D technologies for preparing and implementing MMA., Conclusions: It was confirmed that the accuracy and efficiency of surgery were increased by applying 3D technologies. This suggests that 3D technologies are very useful tools in surgical area., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

After Le Fort I osteotomy was first performed by von Langernbeck in 1859, there has been many improvements since. Research on and development of Le Fort I osteotomy procedure has shown downward movement of the maxilla to exhibit lowest stability and accuracy. However, maxillary downgraft movement is necessary in orthognathic patients with insufficient vertical length of the maxilla, but fixation of the maxilla after elongation is often very inaccurate. In this study, the authors utilized 3D virtual surgery, CAD/CAM-assisted 3D printing technology to overcome such limitations of maxillary total elongation. In addition, accuracy at 7 different landmarks from superimposition of virtual simulation data and postoperative Cone-beam computed tomography (CBCT) data were measured. Although posterior maxilla exhibited bigger range of errors, an error of <1 mm was measured at all 7 landmarks. Operation time was greatly shortened with cutting guides and customized plates. Although this study is a single-case study, this study shows increased accuracy and efficacy from application of 3D virtual surgery, CAD/CAM, and 3D printing technology., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 by Mutaz B. Habal, MD.)

Abstract: This study was performed to evaluate condylar position and angulation after asymmetric mandibular setback between a conventional (CA) and surgery-first approach (SFA) using three-dimensional analysis. The condylar positions of 30 patients with skeletal Class III malocclusion and facial asymmetry who underwent 1-jaw (sagittal split ramus osteotomy) or 2-jaw orthognathic surgery (Le Fort I osteotomy and sagittal split ramus osteotomy) with CA (n = 18) or SFA (n = 12) from 2 university hospitals were studied. The three-dimensional assessment of condylar changes was performed using computed tomography images at the initial time point (T0) and at least 6 months after surgery (T1). Segmentation of condyles and cranial base assessment from cone-beam computed tomography images were performed using ITK-SNAP software (version 3.4.0). Condylar position and angulation changes were calculated using 3D Slicer software (version 4.10.2), and statistical analysis was performed. No significant translational or rotational condylar changes were observed between the deviated and non-deviated sides in each group or between the CA and SFA groups except yaw ( p = 0.014). Linear mixed-model analysis and multi-variate analysis showed no significant difference between the CA and SFA groups. Surgery-first approach might not be associated with more harmful effects on the condylar position and angulation changes as compared with CA., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of Mutaz B. Habal, MD.)

Objective: To evaluate the surgical accuracy of positioning the maxilla in patients with skeletal class II malocclusion using computer-aided design and computer-aided manufacturing (CAD/ CAM)-assisted orthognathic surgery., Materials and Methods: The samples consisted of 10 patients with skeletal class II malocclusion, whose cone-beam computed tomographys taken before and immediately after surgery were available and who underwent bimaxillary orthognathic surgery by a single surgeon using Le Fort I osteotomy and bilateral sagittal split ramus osteotomy at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, Seoul, South Korea between January 2018 and December 2019. After virtual surgical planning was performed using the FACEGIDE system (Korea), surgical cutting guides, intermediate splints, and custom-made titanium mini-plates were fabricated using CAD/CAM technique. Using 8 landmarks (anterior nasal spine, point A, #16, #13, contact point between #11 and #21, #23, #26, posterior nasal spine), the mean differences between the virtually planned (Virtual) and actual postsurgical position of the maxilla (Actual) in the three-dimensional coordinates (ΔActual-Virtual) and their mean absolute deviations were investigated., Results: The mean differences of 8 landmarks were 0.42 mm left side movement in the transverse coordinate, 0.15 mm forward movement in the sagittal coordinate and 0.10 mm downward movement in the vertical coordinate. Their mean absolute deviations were 0.98, 0.67, and 0.62 mm in the sagittal, vertical, and transverse coordinates, respectively., Conclusions: Since the mean difference was less than 0.5 mm and the range of error was less than 1.0 mm, CAD/CAM-assisted orthognathic surgery might have a high degree of surgical accuracy and clinical relevance in the positioning of the maxilla., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Abstract: The purpose of this study was to investigate the type and frequency of use of treatment modalities (Tx-Mods) in patients with syndromic craniosynostosis (SC) using longitudinal follow-up data. A total of 28 patients with SC (24 Crouzon, 2 Apert, and 2 Antley-Bixler syndromes), who were treated at the Department of Orthodontics, Seoul National University Dental Hospital, Seoul, South Korea between 1998 and 2020, was included. According to the degree of midface hypoplasia (MH) at the initial visit (T1), the patients were divided into the mild-MH (78°≤SNA < 80°, n = 8), moderate-MH (76≤SNA < 78°, n = 7), and severe-MH (SNA < 76°, n = 13) groups. T1-age and Tx-Mods, including cal-varial surgery (CALS), orthopedic treatment (OPT), fixed orthodontic treatment, and midface advancement surgery in childhood (MAS-child) and adulthood (MAS-adult), were investigated. Complexity of MAS-adult was graded as follows: 0, no surgery; 1, orthognathic surgery; 2, distraction osteogenesis (DOG); 3, combination of distraction osteogenesis and orthognathic surgery. Then, statistical analysis was performed. Percentage distribution of Tx-Mods was 71.4% in CALS, 21.4% in MAS-child, 42.9% in OPT, 100% in fixed orthodontic treatment, and 89.3% in MAS-adult. 92.9% of patients underwent MAS more than once. The number of MAS increased according to the severity of MH ( P < 0.05). The complexity of MAS-adult increased as T1-age and severity of MH increased (all P < 0.05); whereas it decreased when CALS and OPT were performed (all P < 0.05). However, MAS in childhood did not guarantee the avoidance of additional MAS in adulthood ( P > 0.05). These findings may be used as basic guidelines for successful treatment planning and prognosis prediction in patients with SC., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Objective: To evaluate the accuracy of intentional change of the frontal ramal inclination (FRI) from virtual to actual orthognathic surgery., Materials and Methods: A total of 16 patients who underwent orthognathic surgery for correction of facial asymmetry and took cone-beam computed tomography 2 to 3 weeks before surgery (T0) and 3 days after surgery (T1A) were selected. After reorientation of cone-beam computed tomography, the digital imaging and communications in medicine data was converted to StereoLithography format for the merging with dental cast scan using R2GATE software (MegaGen Implant, Daegu, Republic of Korea). During virtual surgery using Geomagic Freeform Plus software (3D Systems, Rock Hill, SC), bilateral FRI discrepancy was corrected (T1V) and 3D-printed surgical wafers and customized metal plates were manufactured using 3D printer (Meg-printer II, MegaGen Implant, Daegu, Republic of Korea) and computer numerical control milling machine (ARDEN, TPS Korea Ltd., Gwangju, Republic of Korea) accordingly. During surgery, FRI correction was done using surgical guide and customized plates. The difference between preoperative and virtually corrected FRI (Δ T1V - T0) and the difference between preoperative and actually surgically corrected FRI (Δ T1A - T0) were measured, and the achieved FRI correction in percentage ([Δ T1A - T0]/[Δ T1V - T0] × 100) was calculated., Results: The mean absolute value of virtual FRI correction (Δ T1V - T0) and actual FRI correction (Δ T1A - T0) were 3.0° and 2.9°, respectively (n = 32). In the increased (medial rotation) FRI group, mean virtual and actual correction amount were 3.2° and 2.8° (n = 17), whereas in the decreased (lateral rotation) group, mean virtual and actual correction amount were -2.7° and -3.1°, respectively (n = 15). No statistically significant difference between virtual and actual measurements were present in either group. The mean achievement rate was 102.8%. Tendency of undercorrection (91.2%) in the increased FRI group and overcorrection (116.0%) in the decreased FRI group were noted., Discussion: With virtual planning and computer-aided design and computer-aided manufacturing-made customized plates, it is possible to correct FRI during orthognathic surgery of patients with facial asymmetry., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Abstract: The purpose of this study was to investigate the effects of early spheno-occipital synchondrosis (SOS) fusion in preadolescent patients with syndromic craniosynostosis (SC) on the craniofacial skeletal patterns. Twenty preadolescent SC patients were divided into the fused SOS (FS, n = 10; 8 Crouzon and 2 Apert) and not-fused SOS groups (NFS, n = 10; 9 Crouzon and 1 Apert). Lateral cephalograms (mean age: 9.60 years, cervical vertebral maturation index: stage I and II) were used to investigate the skeletal sagittal (ANB) and vertical patterns (SN-GoMe), upward inclination of the anterior cranial base (ACB; SN-FH), degree of midface hypoplasia (MH, SNA), retrusive position of orbitale (SNO), and forward position of the condyle in relation to sella (saddle angle). Using the ordinal values calculated by ethnic norm (criteria: moderate, over ±1 standard deviation, severe, over ±2 standard deviation), statistical analysis was performed. The FS group showed a higher percentage of severe MH than the NFS group (70% versus 10%, P < 0.05). Although the 2 groups did not differ in the distribution of ANB, SN-GoMe, saddle angle, and SN-FH (all P > 0.05), the FS group showed relatively higher percentages of severe Class III (100% versus 70%), severe hyper-divergent pattern (40% versus 10%), severely forward condyle position (30% versus 0%), and moderate and severe upward anterior cranial base inclination (90% versus 50%) than the NFS group. However, the 2 groups exhibited the same distribution of moderately and severely retrusive orbitale position ([50%, 20%], P > 0.05). Early SOS fusion in preadolescent SC patients might not be related to retrusive orbitale position, but to severe MH., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Abstract: The purpose of this study was to investigate three-dimensional facial soft tissue changes after bimaxillary orthognathic surgery (BOGS) in patients with cleft lip and palate. The samples consisted of 34 Korean young adult patients with skeletal class III malocclusion who underwent BOGS for maxillary advancement/posterior impaction and mandibular setback. They were divided into cleft-class III (C-CIII) group (n = 18) and noncleft-class III (NC-CIII) group (n = 16). Three-dimensional computed tomography images were taken 1 month before (T1) and 3 months after (T2) surgery. After 34 hard/soft tissue landmarks were automatically identified using software, the amount and direction of change in landmarks and the amount of change in 16 soft tissue variables during T1-T2 were calculated. Then, statistical analysis was performed. Compared to NC-CIII group, C-CIII group showed more posteriorly-positioned hard/soft tissue landmarks, larger alar width, alar base width and philtrum width, and more obtuse nasal tip angle at both T1 and T2 stages. C-CIII group exhibited higher soft-to-hard tissue movement ratios at the bottom of the nose (ΔSn/ΔANS, 1.08 versus 0.81) and the upper part of the upper lip (ΔPoint A'/ΔPoint A, 1.08 versus 0.91), but a lower ratio at the lower part of the upper lip (ΔLs'/ΔIs, 0.72 versus 1.01) than NC-CIII group. The number of hard-soft tissue landmarks with high correlation (>0.90) was smaller in C-CIII group than in NC-CIII group (2 versus 6). Scar tissues and abnormal muscles in the nose and upper lip might elicit different responses in the nasolabial soft tissues to BOGS between C-CIII and NC-CIII patients., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Abstract: The purpose of this study was to investigate the phenotypes and treatment modalities (Tx-Mod) in patients with Treacher-Collins syndrome (TCS) using a TCS severity index (TSI). The sample consisted of 14 Korean TCS patients treated at the Department of Orthodontics, Seoul National University Dental Hospital during 1998 to 2019. The TSI was calculated by adding the scores from the number of deformity-involved midface structures (eye, ear, zygoma) and the degree of mandibular hypoplasia (Pruzansky-Kaban type, gonial angle, Sella-Nasion-B point angle). The deformity-involved midface structure, degree of mandibular hypoplasia, oral manifestations, dental phenotypes, and Tx-Mod types were investigated using descriptive statistics. The TSI classified the subjects into 2 mild, 6 moderate, and 6 severe cases. The severity of ear and zygoma deformities, degree of condylar hypoplasia (Pruzansky-Kaban type), clockwise-rotated morphology (gonial angle) and retrusive position (Sella-Nasion-B point angle) of the mandible, and frequency of oral/craniofacial cleft, openbite, congenitally missing tooth and impacted tooth showed a tendency of increase from mild to severe TCS cases. After growth observation (78.6%), diverse combinations of Tx-Mods were applied except for functional appliance therapy. Surgical procedures for eye, ear, and zygoma reconstruction were performed on all patients (100%), whereas fixed orthodontic treatment, mandibular distraction osteogenesis, and orthognathic surgery were performed on 50% of patients. Surgical procedure for hearing improvement was the most frequent Tx-Mod (78.6%). The main desires of TCS patients were to obtain the facial esthetics in the midface and to improve hearing function. The TSI might provide a primary data for individualized diagnosis and treatment planning., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Abstract: The purpose of this study was to determine the cephalometric predictors of the future need for orthognathic surgery in patients with repaired unilateral cleft lip and palate (UCLP) using machine learning. This study included 56 Korean patients with UCLP, who were treated by a single surgeon and a single orthodontist with the same treatment protocol. Lateral cephalograms were obtained before the commencement of orthodontic/orthopedic treatment (T0; mean age, 6.3 years) and at at least of 15 years of age (T1; mean age, 16.7 years). 38 cephalometric variables were measured. At T1 stage, 3 cephalometric criteria (ANB ≤ -3°; Wits appraisal ≤ -5 mm; Harvold unit difference ≥34 mm for surgery group) were used to classify the subjects into the surgery group (n = 10, 17.9%) and non-surgery group (n = 46, 82.1%). Independent t-test was used for statistical analyses. The Boruta method and XGBoost algorithm were used to determine the cephalometric variables for the prediction model. At T0 stage, 2 variables exhibited a significant intergroup difference (ANB and facial convexity angle [FCA], all P < 0.05). However, 18 cephalometric variables at the T1 stage and 14 variables in the amount of change (ΔT1-T0) exhibited significant intergroup differences (all, more significant than P < 0.05). At T0 stage, the ANB, PP-FH, combination factor, and FCA were selected as predictive parameters with a cross-validation accuracy of 87.4%. It was possible to predict the future need for surgery to correct sagittal skeletal discrepancy in UCLP patients at the age of 6 years., Competing Interests: The authors have no potential conflicts of interest to disclose., (Copyright © 2020 by Mutaz B. Habal, MD.)

The purposes of this study were to compare the postoperative changes in nasal septal (NS) deviation between total impaction (TI) and anterior elongation (AE) of the maxilla after Le Fort I osteotomy (LF-IO) and to investigate the correlation between the change in NS deviation and the amount of surgical maxillary movement. Twenty-eight patients, who underwent LF-IO and sagittal split osteotomy by a single surgeon, were divided into TI group (N = 13; mean = 1.5 mm) and AE group (N = 15; mean = 1.6 mm). NS deviation was measured using computed tomography and deviation indices before and after surgery at 3 coronal measurement planes (CMP) passing through the nasion, crista galli, and the most anterior point of the sphenoid sinus (MAPS). Then, statistical analysis was performed. The AE group did not have significant changes in any deviation indices after surgery. The TI group; however, exhibited significant increases in the MAPS-CMP and total deviation indices (0.67-1.16 mm, P < 0.01; 5.45-6.43 mm, P < 0.05). The TI group also exhibited a greater increase in the ΔMAPS-CMP deviation index than the AE group (0.49 mm versus 0.06 mm, P < 0.05). The amount of forward movement of the maxilla was positively correlated with the nasion-CMP and total deviation indices (r = 0.422, P < 0.05; r = 0.398, P < 0.05). LF-IO for TI and forward movement can worsen NS deviation posteriorly and anteriorly, respectively. It is necessary to manage the nasal septum and the nasal crest of the maxilla meticulously during LF-IO procedure.

Background: Fat grafting has been widely used for facial rejuvenation and soft tissue reconstruction. However, it is associated with a lower retention rate than expected and complications such as fat necrosis or calcification. Several techniques that may increase the survival rate of fat grafts have been proposed. The techniques that promote the recipient sites vascularity to increase the survival rate of fat grafts include administration of growth factors, platelet- rich plasma, and adipose derived-stem cells or preconditioning of the recipient fat graft site., Methods: In this study, the authors evaluated the effect of hyaluronidase on autologous fat graft survival by pretreatment with hyaluronidase at the recipient site by using an animal model. In the experimental group, the recipient site of the fat graft was pretreated with hyaluronidase before fat grafting, whereas the control group was pretreated with normal saline., Results: After 8 weeks of fat grafting, the average volume retention was 78.2% in the experimental group and 68.6% in control group. Considerable fibrosis between the fat globules in the control group was confirmed with Masson trichrome staining. CD31 immunofluorescence staining was performed and stained vessels were counted. Counted vessel number was significantly greater in the experimental group than in the control group., Conclusions: Pretreatment of hyaluronidase on the fat graft recipient site is a good option to enhance the outcome of the fat graft in the clinical setting.

Diagnosis and treatment planning are the most important steps in the orthognathic surgery for the successful treatment. The purpose of this study was to develop a new artificial intelligent model for surgery/non-surgery decision and extraction determination, and to evaluate the performance of this model. The sample used in this study consisted of 316 patients in total. Of the total sample, 160 were planned with surgical treatment and 156 were planned with non-surgical treatment. The input values of artificial neural network were obtained from 12 measurement values of the lateral cephalogram and 6 additional indexes. The artificial intelligent model of machine learning consisted of 2-layer neural network with one hidden layer. The learning was carried out in 3 stages, and 4 best performing models were adopted. Using these models, decision-making success rates of surgery/non-surgery, surgery type, and extraction/non-extraction were calculated. The final diagnosis success rate was calculated by comparing the actual diagnosis with the diagnosis obtained by the artificial intelligent model. The success rate of the model showed 96% for the diagnosis of surgery/non-surgery decision, and showed 91% for the detailed diagnosis of surgery type and extraction decision. This study suggests the artificial intelligent model using neural network machine learning could be applied for the diagnosis of orthognathic surgery cases.

Objective: The aim of this study was to compare the degrees of satisfaction with orthognathic surgery and orthodontic treatment between skeletal Class III and cleft patients., Materials and Methods: The samples consisted of Class III group (N = 25) and Cleft group (N = 16). The Modified Orthognathic Quality of Life Questionnaires, which had 5 domains (oral function [OF], awareness of dentofacial deformity [ADD], social relationship [SR], facial esthetics [FE], and nose/lip esthetics [NLE]), were evaluated with 5 rates (0 [very satisfactory] to 4 [very unsatisfactory]) at initial visit (T1), just before surgery (T2), 3 to 6 months after surgery (T3), and at debonding or 1 year after surgery (T4). The scores at each stage, amount of change between stages, and effect size (ES) in the 5 domains were investigated., Results: Compared to Class III group, Cleft group exhibited lower satisfaction scores of NLE domain during all stages (all P < 0.001) and of SR domain and total domains at T4 stage (P < 0.05, P < 0.01). Cleft group showed significant improvement of satisfaction scores in FE domain during T1-T2 (P < 0.01), in SR, FE, NLE, and total domains during T2-T3 (all P < 0.01), in OF, SR, and total domains during T3-T4 (P < 0.05, P < 0.01, P < 0.01), and in all domains during T1-T4 (ADD, P < 0.05; OF, SR, and NLE, P < 0.01; FE and total, P < 0.001). Cleft group exhibited large improvement of ES only at SR and FE domains during T2-T3 (-0.81 and -1.09, respectively)., Conclusions: Owing to lower satisfaction of NLE domain at all stages in cleft patients, clinicians should recommend adjunctive cosmetic surgery for nose and lip after completion of treatment.

Objective: The purpose of this clinical report was to introduce a new methodology for contour restoration of the over-resected mandible by reduction mandibuloplasty using 3-dimensional (3D) planning and computer-assisted design and manufacturing (CAD-CAM) custom-made titanium implants., Patient and Method: A 20-year-old male patient had undergone reduction of the zygoma and mandibular angle and lower border for esthetic reason 1 year ago at a private clinic. However, he was not satisfied with surgical outcome and wanted to restore his original facial volume and contour. To assess the volume and dimension of resected bone, 3D-computed tomography (3D-CT) data at the original stage was superimposed with postsurgical CT. For restoration of the malar prominence, porous polyethylene malar implants with extensions into the lateral malar region (Medpor) were placed and fixed with microscrews. Custom-made titanium implants were fabricated for contour restoration of the mandibular angle and lower border using CAD-CAM technology (iDDA, Daegu, South Korea). Two-piece design per each titanium implant was adopted for easy placement and avoidance of tissue damage during placement. Thin buccal extension was incorporated for placement of screw holes. Location, direction, and length of bicortical screws were planned to avoid damage of the inferior alveolar nerve., Result: With the help of 3D planning and CAD-CAM technology, rigid fixation of the custom-made titanium implants into the mandibular angle and lower border successfully restored the contour of over-resected mandible to the original state., Conclusion: When over-resection by reduction mandibuloplasty becomes an issue, this method may be an effective treatment option for contour restoration of over-resected mandibular angle and lower border.

The purpose of this study was to investigate the heritability of facial skeletal and dental characteristics of the monozygotic (MZ) and dizygotic (DZ) twins. The samples consisted of Korean MZ and DZ twins (n = 13 pairs/each twin; 7 pairs of males and 6 pairs of females; mean age, 39 years, respectively). The linear, angular, and ratio variables, which could describe the size and shape of the facial horizontal and vertical, dental, mandible and cranial base structure, were measured. The Falconer's method was used to calculate the heritability (h; close to or below 0, low heritability; close to or above 1, high heritability). In the facial horizontal and vertical aspects, the highest h values were shown at SNA (degree, 1.53), SNB (degree, 2.12), SN-Pog (degree, 2.19), SN-palatal plane angle (degree, 1.29), SN-mandibular plane angle (degree, 1.59), N-ANS/ANS-Me (1.66), and ANS-Me/N-Me (1.62). In the dental aspects, although L1-occlusal plane angle (degree, 1.38) and SN-occlusal plane angle (degree, 2.09) showed high h values, most of the dental variables showed low h values. In the mandible and cranial base, lower gonial angle, mandibular body length, and cranial base angle showed high h values (N-Go-Gn [degree], 1.07; Go-Pog [mm], 0.92; N-S-Ba [degree], 1.51). The descending order of the overall mean h values was the facial horizontal (1.10), facial vertical (0.71), mandible (0.59), cranial base (0.37), and dental characteristics (-0.11). The shape of facial skeletal structure and location of the occlusal plane within skeletal framework was more influenced by genetic factors than environmental factors.

The purpose of this retrospective study was to investigate the effect of a long-term use of facemask with miniplate (FM-MP) on maxillary protraction in cleft lip and palate (CLP) patients. The subjects were 21 CLP patients (16 unilateral CLP and 5 bilateral CLP patients), who were treated with identical lip and palate surgical method and FM-MP therapy performed by single surgeon and single orthodontist. Lateral cephalogram was taken before (T1; mean age, 11.1 years) and after maxillary protraction (T2; mean age, 16.9 years). The mean duration of FM-MP was 68.0 months. After 17 cephalometric variables were measured, statistical analysis was performed. During T1-T2, the maxilla showed significant forward movement (ΔA-vertical reference plane, 4.8 mm, P < 0.001; ΔSNA, 1.9 degree, P < 0.001; ΔA-N perp, 1.9 mm, P < 0.05), although the mandible exhibited a forward growth (ΔSNB, 1.2 degree, P < 0.05). Despite downward movement of the posterior maxilla with counterclockwise rotation (Δpalatal plane angle, -1.5 degree, P < 0.05), the mandible did not exhibit clockwise rotation but counterclockwise rotation (ΔSN to mandibular plane angle, -1.4 degree, ΔBjork sum, -1.4 degree, Δocclusal plane to SN plane angle, -1.5 degree, ΔFMA, -1.0 degree, all P < 0.05) and showed decrease in Gonial angle (-1.2 degree, P < 0.01). Although there was labioversion of the maxillary incisor (ΔU1 to SN, 4.1 degree, P < 0.05), the mandibular incisor did not exhibit significant linguoversion (ΔIMPA, -1.3 degree, P > 0.05). Long-term use of FM-MP is effective on maxillary protraction in adolescent CLP patients without clockwise rotation of the mandible, the main drawback of conventional facemask with tooth-borne anchorage.

The purpose of this study was to investigate differences in the alignment pattern of the collapsed maxillary arch following fixed orthodontic treatment (FOT) in bilateral cleft lip and palate (BCLP) patients according to collapse type. Fifteen BCLP patients were divided into Group 1 (anteroposterior-collapsed arch, n = 7) and Group 2 (transverse-collapsed arch, n = 8) according to maxillary arch shape before FOT. Linear and angular variables of lateral cephalograms and dental models were evaluated before (T1) and after FOT (T2), and statistical analysis was performed. In cephalometric measurements at T1, both the groups exhibited retrusive maxillae, a Class III relationship, and lingual inclination of U1-SN. At T2, significant improvement of U1-SN was observed in both the groups (P < 0.01 in Group 1; P < 0.05 in Group 2). In the model measurements at T1, the inter-second premolar width (IP2W), inter-first molar width (IM1W), and left segmental angle were smaller in Group 2 than in Group 1 (IP2W, P < 0.001; IM1W, P < 0.05; LSA, P < 0.05). From T1 to T2, the arch width increased significantly in Group 2 (inter-canine width, IP1W, IP2W, and IM1W; all P < 0.05), but not in Group 1. Therefore, there were significant differences in ΔIP2W (2.4 mm versus 14.9 mm, P < 0.01) and ΔIM1W (-0.7 mm versus 5.9 mm, P < 0.001) between Groups 1 and 2. In both the groups, the molar depth and right and left segmental angles increased significantly, while the premaxillary rotation angle decreased significantly (molar depth, RSA, LSA, and PMRA; all P < 0.05). The alignment strategy for the maxillary premolar and molar areas should be modified according to arch shape in BCLP patients.

The purpose of this study was to compare the alignment pattern of the constricted maxillary dental arch by fixed orthodontic treatment (FOT) in the well-aligned and constricted arches of unilateral cleft lip and palate (UCLP) patients. 19 UCLP patients were divided into Group 1 (well-aligned arch, n = 9) and Group 2 (constricted arch, n = 10). After the cephalometric and maxillary dental arch variables before (T1) and after FOT (T2) were measured, statistical analysis was performed. There were no significant differences in the surgical timing of cheiloplasty, palatoplasty, and secondary alveolar bone grafting and in the surgical method of cheiloplasty between the 2 groups. However, Group 2 had a higher percentage of palatoplasty method, which could leave the denuded bone for secondary healing than Group 1 (P < 0.05). Although Group 2 showed more constriction and asymmetry in the maxillary dental arch compared to Group 1 at the T1 stage (inter-second premolar width, greater segment angle [GSA], and lesser segment angle [LSA], all P < 0.05), these problems could be effectively resolved by FOT. As a result, at the stage T2, there was no significant difference in all the variables between the 2 groups. During T1-T2, there was a different pattern in change of variables between Groups 1 and 2 (anterior segment angle in the greater segment [P < 0.05] in Group 1 and U1-SN [P < 0.01], inter-molar width [P < 0.05], GSA [P < 0.05[, and LSA [P < 0.01] in Group 2). Therefore, according to the maxillary dental arch shape, different strategy is necessary to obtain proper alignment by FOT.

The purpose of this study was to investigate the amount and pattern of postsurgical relapse after 2-jaw surgery in cleft lip and palate patients in terms of the sagittal and vertical aspects. The samples consisted of 21 adult patients who had the similar initial skeletodental pattern before surgery and underwent 2-jaw surgery. They were divided into high relapse (n = 11) and low relapse groups (n = 10) (criteria, 30% forward relapse of the B point). After the cephalometric variables of cephalograms taken at 1 month before surgery (T0), immediately after surgery (T1), and at least 1 year after surgery (T2) were measured, the Wilcoxon test, Mann-Whitney U test, and Pearson correlation test were performed for statistical analysis. When compared with the low relapse group, the high relapse group exhibited significant counterclockwise rotation of the distal segment of the mandible resulting in more forward movement of the mandible and significant labioversion of the maxillary incisors during T1-T2. The amount of postsurgical relapse of the mandible had a positive relationship with the amounts of setback and clockwise rotation of the mandible with surgery. In addition, the more decrease in overbite through surgery occurred, the more relapse (forward movement of the mandible) produced. Therefore, for the prevention of significant postsurgical relapse of the mandible in cleft patients, it is necessary to reduce unnecessary clockwise rotation of the mandible and to increase the vertical stability of maxilla during orthognathic surgery.

The purpose of this study was to compare the results of two- (2D) and three-dimensional (3D) measurements for the alveolar molding effect in patients with unilateral cleft lip and palate. The sample consisted of 23 unilateral cleft lip and palate infants treated with nasoalveolar molding (NAM) appliance. Dental models were fabricated at initial visit (T0; mean age, 23.5 days after birth) and after alveolar molding therapy (T1; mean duration, 83 days). For 3D measurement, virtual models were constructed using a laser scanner and 3D software. For 2D measurement, 1:1 ratio photograph images of dental models were scanned by a scanner. After setting of common reference points and lines for 2D and 3D measurements, 7 linear and 5 angular variables were measured at the T0 and T1 stages, respectively. Wilcoxon signed rank test and Bland-Altman analysis were performed for statistical analysis. The alveolar molding effect of the maxilla following NAM treatment was inward bending of the anterior part of greater segment, forward growth of the lesser segment, and decrease in the cleft gap in the greater segment and lesser segment. Two angular variables showed difference in statistical interpretation of the change by NAM treatment between 2D and 3D measurements (ΔACG-BG-PG and ΔACL-BL-PL). However, Bland-Altman analysis did not exhibit significant difference in the amounts of change in these variables between the 2 measurements. These results suggest that the data from 2D measurement could be reliably used in conjunction with that from 3D measurement.

The purpose of this study was to investigate the effect of physical therapy for smile improvement on the smile esthetics-related properties after orthognathic surgery. The samples consisted of 44 adult patients (13 males and 31 females; mean age of 22.6 years old), who had undergone LeFort I osteotomy and BSSRO by a single surgeon. After a video clip of smile education was shown to patients (see Supplemental Digital Content, Video, http://links.lww.com/SCS/A238), smile training of 5 minutes per day was started 1-month after surgery for 3 months. Frontal facial photographs of the posed smile were taken before (T1, 1 month after surgery) and after smile training (T2, 4 months after surgery). Five variables including the smile height, upper lip curvature, smile arc, most visible maxillary posterior tooth, and buccal corridor ratio during posed smile were investigated. When compared with the T1 stage, the T2 stage showed improvement of the smile height (average or high: 32% versus 50%, P <0.05), upper lip curvature (upward: 52% versus 73%, P <0.05), most visible maxillary posterior tooth (first premolar: 48% versus 59%, P <0.05), and buccal corridor ratio (14% versus 11%, P <0.05). Although the smile arc did not show significant difference (P >0.05), there was a tendency of increase in the parallel smile arc from 77% at T1 to 82% at T2.In this small cohort of patients, for the period of observation, it appears that this smile training improves the smile esthetics-related properties in orthognathic surgery patients. However, it is necessary to perform further long-term follow-up studies with control groups.

Objective: The aim of the study was to compare the effect of conventional maxillomandibular advancement (MMA) and modified MMA with anterior segmental setback osteotomy (MMA-ASSO) on the airway changes in patients with obstructive sleep apnea syndrome (OSAS) using three-dimensional computational fluid dynamics (3D-CFD) analysis., Methods: Two adult male patients with Class I malocclusion, lip protrusion, acute nasolabial angle, and OSAS were treated with conventional MMA (Case 1) and modified MMA-ASSO (Case 2). Individualized 3D airway models were fabricated using computed tomography data obtained 1 month before (T0) and at least 6 months after surgery (T1). A total of 7 cross-sectional areas of the airway were established, starting just above the hard palate (plane 1) with interval of 1 mm caudally. Airflow velocity and negative pressure were investigated using CFD analysis, and polysomnography studies were performed at T0 and T1., Results: There were improvement of apnea-hypoapnea index and the lowest O2 level (T0 versus T1; 43.2 versus 15.2, 79% versus 90% in Case 1; 61.0 versus 6, 89% versus 92% in Case 2). At plane 2 (retropalatal area) in Cases 1 and 2, there were increase in the smallest cross-sectional areas (57.9% versus 28.4%), decrease in the airflow velocity and increase in the negative pressure at the peak of expiration (49.5% versus 31.7%; 88.4% versus 54.3%), end after expiration (53.2% versus 32.2%; 83.2% versus 47.9%), and peak of inspiration (53.1% versus 29.2%; 75.3% versus 48.2%)., Conclusion: Modified MMA-ASSO method might be an effective treatment option for OSAS patients with improvement of airway problems and esthetic facial profile.

The aim of this study was to investigate the pattern, amount, and distribution of postsurgical relapse in skeletal Class III patients treated with two-jaw surgery (TJS) using conventional three-stage method (CTM) and surgery-first approach (SFA). A total of 38 patients who underwent the nonextraction approach and TJS (LeFort I posterior impaction and mandibular setback) were divided into CTM and SFA groups (all n = 19/group). Lateral cephalograms were taken before treatment (T0), at 1 month before surgery (T1), immediately after surgery (T2), and at debonding (T3) for CTM patients and at T0, T2, and T3 stages for SFA patients. Cephalometric measurements and statistical analyses were performed. There were no significant differences in the cephalometric variables at all stages except maxillary incisor inclination (U1-UOP) and overbite at T0 between 2 groups. They also did not exhibit significant differences in the amounts of surgical movement except for advancement of the maxilla. The mandible in both groups was rotated slightly clockwise by surgery and counterclockwise during T2-T3 without a significant difference. Distribution of cases with "high relapse" (>30%) and "low relapse" (<30%) of the mandible differed for 2 groups (P < 0.05). SFA group had more "high relapse" cases than CTM group (57.9% versus 26.3%). Postsurgical relapse of the mandible had a positive relationship with the amount of mandibular setback in SFA group (P < 0.01) and clockwise rotation of the proximal segment of the mandible in both groups (P < 0.05 and P < 0.01). The results suggest that SFA might be an effective alternative to CTM if the cause of "high relapse" including amounts of mandibular setback and clockwise rotation of the proximal segment of the mandible during surgery can be controlled.

Objective: To compare the quality of life (QoL) of Class III patients between conventional three-stage method (CTM) and surgery-first approach (SFA) using Orthognathic QoL Questionnaire (OQLQ)., Materials and Methods: The subjects consisted of 26 Class III patients treated with nonextraction and two-jaw surgery. They were divided into CTM group (N = 15) and SFA group (N = 11). They retrospectively rated the OQLQ scores of 4 domains (social relationship, facial esthetics, function, and awareness of dentofacial deformity) using 0 to 4 scale at initial (T0), just before surgery (T1), 3 month after surgery (T2), and at debonding (T3). Mann-Whitney test and Wilcoxon signed-rank test were performed for statistical analysis., Results: After total OQLQ score of CTM group was deteriorated at T1 stage compared with T0 stage, it was improved at T2 and T3 stages (T0 = 53.9, T1 = 58.1, T2 = 23.5, and T3 = 11.6). Total OQLQ score of SFA group, however, was improved at T2 and T3 stages compared with T0 stage (T0 = 51.6, T2 =  3.1, and T3 = 11.4; T1 was omitted.). Orthognathic QoL Questionnaire scores and their amounts of change did not show any significant difference in each domain and at each stage between 2 groups (T0, T2, T3, ΔT2 - T0, ΔT3 - T2, ΔT3 - T0; all P > 0.05). Both groups showed large change in effect size (ES) of all domains with descending order during T3 - T0: facial esthetics, oral function, social relationship, and awareness of dentofacial deformity (CTM group: -3.97, -3.40, -2.23, -1.25; SFA group: -2.83, -2.33, -1.76, -1.73) CONCLUSIONS: SFA might have an advantage over CTM group in terms of no deterioration stage of OQLQ score.

The purpose of this study was to investigate the effect of secondary alveolar bone grafting (SABG) on the maxillary growth in patients with unilateral (UCLP) and bilateral cleft lip and palate (BCLP). The samples consisted of 40 Korean boy cleft patients who had the similar initial skeletal characteristics and were treated with the identical treatment protocol. They were divided into UCLP group (N = 25; mean SABG age, 9.9 years; mean follow-up duration, 42.3 months) and BCLP group (N = 15; mean SABG age, 10.2 years; mean follow-up duration, 40.6 months). In the lateral cephalograms taken 1 month before (T1) and at least 2 years after SABG (T2), cephalometric variables were measured. At T1 stage, the 2 groups did not exhibit significant differences in the cephalometric variables except posterior maxillary height (P-HRP) (P < 0.05). At T2 stage, both groups exhibited the reduced sagittal growth (UCLP, ANB, P < 0.001; AB to facial plane angle (AB-FPA), P < 0.01; BCLP, A to N perpendicular, P < 0.05; ANB and AB-FPA, P < 0.001) and the undisturbed vertical growth (A-HRP and P-HRP, all P < 0.001) of the maxilla. During T1 to T2, BCLP group experienced more aggravation of Class III skeletal pattern than UCLP group (ΔAB-FPA, P < 0.05). There, however, were no differences in the amounts of changes in the maxillary vertical position and mandibular plane angulation between the 2 groups. Two-stage SABG procedure subgroup in patients with BCLP demonstrated a more retrusive maxilla compared with 1-stage SABG procedure subgroup (ΔSNA, P < 0.05). Patients with BCLP, especially who underwent 2-stage SABG procedure, might have a possibility of poor sagittal growth of the maxilla compared with patients having UCLP.

The purpose of this study was to determine the cephalometric variables that can predict the future need for orthognathic surgery or distraction osteogenesis in Korean male patients with nonsyndromic cleft lip and alveolus (CLA) and unilateral (UCLP) and bilateral cleft lip and palate (BCLP). A total of 131 patients who were treated by one surgeon and one orthodontist using identical protocol were divided into CLA group (n = 35), UCLP group (n = 56), and BCLP group (n = 40). Lateral cephalograms were taken before secondary alveolar bone graft (T0; mean age, 9.3 years) and at the minimum of 15 years of age (T1; mean age, 17.3 years). The cephalometric variables of these cephalograms were measured. At T1 stage, 3 cephalometric criteria were used to divide the subjects into surgery and nonsurgery groups (ANB ≤ -3 degrees; Wits appraisal ≤ -5 mm; Harvold unit difference ≥ 34 mm for surgery group). The feature wrapping method was used to determine the cephalometric variables at T0 stage for a prediction model. At T1 stage, 27 (20.6%) of 131 subjects required surgical intervention to correct their sagittal skeletal discrepancies. Frequency was significantly different among the CLA, UCLP, and BCLP groups (8.5%, 21.4%, and 30.0%, respectively; P < 0.05; [CLA, UCLP] < [UCLP, BCLP]). A total of 10 cephalometric variables of T0 stage were selected as predictors, and weighted classification accuracy was 77.3%. The frequency of surgical intervention increased with cleft severity. Ten cephalometric variables might be regarded as effective predictors of the future need for surgery to correct their sagittal skeletal discrepancies.

The aim of our study was to evaluate the effect of cant correction in the anterior (AMXTOP) and posterior maxillary transverse occlusal planes (PMXTOP) on the change in lip cant (LC) using three-dimensional facial scan (FS) in conjunction with computed tomographic (CT) images. Thirty-five class III asymmetry patients treated with 2-jaw surgery were selected. Three-dimensional CT and three-dimensional FS images were taken before (T1) and after orthognathic surgery (T2). After obtaining the same head orientation between 2 images, bracket slot midpoints of the maxillary right and left canines as well as the first molars, point A, point B, and menton on three-dimensional CT images and the right and left lip commissures on three-dimensional FS images were located. Linear and angular variables of AMXTOP, PMXTOP, and LC were measured and statistically analyzed. At the T1 stage, linear and angular LC showed significant correlations with linear and angular cant of AMXTOP and PMXTOP, as well as menton deviation (all P < 0.001). During T1 to T2, significant linear and angular cant corrections were observed: ΔAMXTOP (1.3 mm, 1.9 degrees), ΔPMXTOP (1.9 mm, 1.7 degrees), and ΔLC (1.5 mm, 1.8 degrees) (all P < 0.001). Although angular change ratios of ΔLC/ΔAMXTOP and ΔLC/ΔPMXTOP did not exhibit a significant difference (1.0 vs 0.7), linear change ratio of ΔLC/ΔAMXTOP was higher than that of ΔLC/ΔPMXTOP (3.0 vs 0.5, P < 0.05). The vertical change in commissures was related to that in the maxillary right and left canines or maxillary right and left first molars and the extent of mandibular setback (all P < 0.01). To conclude, the use of three-dimensional FS images in conjunction with three-dimensional CT can provide more accurate information for changes in AMXTOP, PMXTOP, and LC.

This study was performed to evaluate the efficacy of computer-aided design/computer-aided manufacturing (CAM/CAD)-made condyle positioning jig in orthognathic surgery. The sample consisted of 40 mandibular condyles of 20 patients with class III malocclusion who underwent bilateral sagittal split ramus osteotomy with semirigid fixation (6 men and 14 women; mean age, 25 y; mean amount of mandibular setback, 5.8 mm). Exclusion criteria were patients who needed surgical correction of the frontal ramal inclination and had signs and symptoms of the temporomandibular disorder before surgery. Three-dimensional computed tomograms were taken 1 month before the surgery (T1) and 1 day after the surgery (T2). The condylar position was evaluated at the T1 and T2 stages on the axial, frontal, and sagittal aspects in the three-dimensional coordinates. The linear change of the posterior border of the proximal segment of the ramus between T1 and T2 was also evaluated in 30 condyles (15 patients), with the exception of 10 condyles of 5 patients who received mandibular angle reduction surgery. There was no significant difference in the condylar position in the frontal and sagittal aspects (P > 0.05). Although there was a significant difference in the condylar position in the axial aspect (P < 0.01), the amount of difference was less than 1 mm and 1 degree; it can be considered clinically nonsignificant. In the linear change of the posterior border of the proximal segment of the ramus, the mean change was 1.4 mm and 60% of the samples showed a minimal change of less than 1 mm. The results of this study suggest that CAD/CAM-made condyle positioning jig is easy to install and reliable to use in orthognathic surgery.

The purpose of this retrospective study was to compare the durations of total treatment (TT), and preoperative orthodontic treatment (Pre-OP-OT) and postoperative orthodontic treatment (Post-OP-OT) between conventional 3-stage method (CTM) and surgery-first approach (SFA). The subjects consisted of skeletal Class III patients who were treated with non-extraction and 2-jaw surgery and had lateral cephalograms taken at initial visit (T0), 1 month before surgery (T1), immediately after surgery (T2), and at debonding (T3). They were allocated into group 1 (CTM, n = 26) and group 2 (SFA, n = 18, including the subjects with Pre-OP-OT shorter than 100 days). Statistical analysis was performed after measuring skeletodental variables in the T0 lateral cephalogram, the amount of surgical change (ΔT2-T1), and the durations of TT, Pre-OP-OT, and Post-OP-OT. There were no significant differences in skeletodental variables at the T0 stage or in ΔT2-T1 between groups 1 and 2. Therefore, differences in durations of TT and Post-OP-OT between groups 1 and 2 could be attributed to the difference in treatment methods (CTM vs. SFA). TT and Pre-OP-OT were significantly longer in group 1 than those in group 2 (324.2 days and 385.7 days, respectively; all P < 0.001). Although Post-OP-OT was longer in group 2 than in group 1, the difference was not significant (63.3 days; P > 0.05). In group 1, the negative correlation between durations of Pre-OP-OT and Post-OP-OT was not verified, which means that Post-OP-OT was not shortened despite longer Pre-OP-OT. The results from this study can be used as a guideline in diagnosis and treatment planning for SFA.

The purpose of this retrospective study was to evaluate the changes in the upper lip (UL) by posterior impaction and setback (PI-SB) of the maxilla. The samples consisted of 29 skeletal Class III patients (10 men and 19 women) who received bimaxillary surgery including PI-SB of the maxilla after Le Fort I osteotomy. Lateral cephalograms were taken at 1 week before surgery (T0) and 6 months after surgery (T1). After linear and angular changes of the hard and soft tissue variables were measured, the paired t test, Pearson correlation test, and univariate linear regression analysis were performed for statistical analyses. The changes in the hard tissue landmarks were as follows: ANS, U1E, and U6MBC moved backward (P < 0.001, P < 0.001, and P < 0.05, respectively) and upward (P < 0.001, P < 0.01, and P < 0.001, respectively), whereas A point, U1A, and PNS moved upward only (P < 0.01, P < 0.01, and P < 0.001, respectively). In terms of the soft tissue change, although subnasale (Sn) did not show significant change, pronasale (Pn) moved upward (P < 0.05); UL, backward and downward (all P < 0.001); and Stms (stomodium-superius), backward (P < 0.001). There were significant correlations between the horizontal change of the UL and that of A point and U1E (P < 0.01, P < 0.05). The regression equation of the horizontal change of UL and U1E was [INCREMENT]UL-vertical reference line (VRL) = (0.476 × [INCREMENT]U1E-VRL) - 0.581 (P < 0.05). If U1E moves backward by 3 mm and 5 mm, the UL is predicted to move backward by 0.9 mm and 1.8 mm, respectively. These results might provide a guideline in diagnosis and treatment planning for maxillary surgery with PI-SB.

The aim of this study was to report the treatment results and complications of cranial bone reconstruction in patients with craniosynostosis at the Seoul National University Children's Hospital over the 14-year period from 1996 to 2009. A retrospective study was undertaken on 96 cases of 94 consecutive patients diagnosed with craniosynostosis, operated on between 1996 and 2009. The authors collected the data regarding age at surgery, operative time, duration of hospitalization, and follow-up period. Surgical results including the amount of blood loss, signs related to increased intracranial pressure, aesthetic results, cranial index, and complications were evaluated. The authors compared these results with those of the past 10-year period from 1986 to 1995 at the same hospital. There were 81 patients with single synostosis and 13 patients with multiple synostoses. The age of patients ranged from 3 months to 130 months (mean, 27.9 months). The mean operative time was 7.54 ± 1.77 hours. The duration of hospital stay ranged from 5 to 70 days with a mean period of 8.97 days. The intraoperative loss of hemoglobin ranged from 0 to 9.2 g/dL (mean, 2.35 g/dL). The symptoms of increased intracranial pressure were improved after cranioplasty. With regard to aesthetic results, 94 patients were classified into category I and 2 into category IV. The cranial index decreased from 88.0% ± 1.2% to 86.9% ± 1.1% on average. There were 34 minor complications in 28 operations (29.2%). There were statistically significant differences in age at surgery, operative time, duration of hospital stay, and reoperation rate between the recent 14-year study and the past 10-year study. We observed good surgical results and low complications of cranial bone reconstruction in patients with craniosynostosis. The results of the recent 14-year operations were better than those of the past 10-year operations.

Aesthetic units of the face can be divided into facial content (FC; eyes, nose, lips, and mouth), anterior facial frame (AFF; a contour line from the trichion, the temporal line of the frontal bone, the lateral orbital rim, the most lateral line of the anterior part of the zygomatic body, the anterior border of the masseter muscle, to the inferior border of the chin), and posterior facial frame (PFF; a contour line from the hairline, the zygomatic arch, to the ramus and gonial angle area of the mandible). The size and shape of each FC and the balance and proportion between FCs create a unique appearance for each person. The facial form can be determined through the combination of AFF and PFF. In the Asian population, clinicians frequently encounter problems of FC (eg, acute nasolabial angle, protrusive and everted lips, nonconsonant lip line, or lip canting), AFF (eg, midface hypoplasia, protrusive and asymmetric chin, vertical deficiency/excess of the anterior maxilla and symphysis, or prominent zygoma), and PFF (eg, square mandibular angle). These problems can be efficiently and effectively corrected through the combination of hard tissue surgery such as anterior segmental osteotomy, genioplasty, mandibular angle reduction, malarplasty, and orthognathic surgery. Therefore, the purposes of this article were to introduce the concepts of FC, AFF, and PFF, and to explain the effects of facial hard tissue surgery on facial aesthetics.

The purpose of this study was to investigate the contribution of PAX9 gene to the risk of nonsyndromic cleft lip with or without cleft palate (NS-CL/P). The samples consisted of 142 Korean NS-CL/P families (90 males and 52 females; 9 cleft lip, 26 cleft lip and alveolus, and 107 cleft lip and palate; 76 trios and 66 dyads). A total of 10 single-nucleotide polymorphisms (SNPs) were tested for association with Korean CL/P case-parent trios using transmission disequilibrium test (TDT) and conditional logistic regression models. The minor allele frequency, heterozygosity, and a χ test for Hardy-Weinberg equilibrium at each SNP were computed between parents. Pairwise linkage disequilibrium was computed as both D' and r2 for all SNPs. Both allelic and genotypic TDTs were performed for individual SNPs using family-based association test program. Sliding windows of haplotypes consisting of 2 to 8 SNPs were tested using haplotype-based association test program. Genotypic odd ratios were obtained from conditional logistic regression models using STATA software. The family-based TDT using individual SNPs and 2- to 8-SNP haplotypes of the gene indicated a significant association at rs17104928 (P = 0.014). The haplotype analysis revealed that the association was most significant for the haplotype consisting of 3 SNPs (rs2073247, rs17104928, and rs17176643; P = 0.007). G/A heterozygote at rs17104928 had a significantly increased association with NS-CL/P (genotypic odd ratio, 2.88; 95% confidence interval, 1.42-5.84; P = 0.0014, dominant model). The high-risk SNP and genotype may provide a better understanding of the etiologic role of PAX9 gene in NS-CL/P and potential options for genetic counseling.

Recently, surgical-orthodontic treatment without preoperative orthodontic treatment (known as the surgery-first approach or SFA) has been proposed to improve facial aesthetics from the beginning of treatment, to shorten the entire treatment period, and to take advantage of the regional accelerated phenomenon for orthodontic tooth movement. The SFA concept involves the prediction and simulation of dental alignment, incisor decompensation, and arch coordination using manual setup models. Based on this, decisions regarding the surgical movement of the maxilla and mandible can be made to correct skeletal discrepancies through manual model surgery (MMS). Although several three-dimensional (3D) virtual model surgery (VMS) programs have been introduced to reduce time-consuming manual laboratory procedures and potential errors, these programs still require three-dimensional-computed tomography data and involve complex computerized maneuvers. Because it is difficult to acquire 3D-computed tomographic scans in all cases, a 2.5-dimensional VMS program using two-dimensional lateral and posteroanterior cephalograms and 3D virtual dental models (3Txer version 2.5; Orapix, Seoul, Korea) has been introduced. In addition, because accurate prediction of postoperative orthodontic treatment is crucial for controlling dental alignment, incisor decompensation, arch coordination, and occlusal settling, a new 3D virtual orthodontic treatment system that can construct 3D virtual models, execute a 3D virtual setup, place virtual brackets at predetermined positions, and fabricate transfer jigs with customized bracket base for indirect bonding using a stereolithographic technique has also been developed. The purpose of this article was to introduce the methodology of 2.5-dimensional VMS and 3D virtual postoperative orthodontic treatment using a stereolithographic technique in SFA for a class III open-bite case.

One of the important clinical findings in hemifacial microsomia (HFM) is facial asymmetry (FA) with unilateral underdevelopment and malformation of the mandible and/or maxilla. Unilateral distraction osteogenesis (UDOG) of the mandible has been used for correction of FA in HFM patients. However, return to the original FA status often occurs because of contraction of the distracted bony segment of the mandible and insufficient compensatory downward growth and skeletal midline correction of the maxilla on the affected side. Although bimaxillary UDOG procedure in the maxilla with Le Fort I osteotomy and the mandible with ramus osteotomy was suggested as an alternative treatment modality, it has some disadvantages including elongation of the face, inaccuracy of vector control, and less predictable results. Occlusal plane canting, skeletal midline deviation of the maxilla, and unilateral mandibular hypoplasia might be simultaneously corrected by fixation of the maxilla into a proper position after Le Fort I osteotomy and UDOG of the mandible. Three-dimensional virtual simulation using three-dimensional computed tomography data could help to accurately predict surgical outcomes. In addition, transarch elastic traction from the orthodontic mini-implants on the unaffected side of the mandible to the maxillary posterior teeth on the affected side can produce a plastic molding of the regenerated bone in the distraction area of the mandible and induce compensatory dentoalveolar downward development of the maxillary posterior teeth. Therefore, the purpose of this article was to introduce a new approach for the surgico-orthodontic treatment consisting of simultaneous maxillary fixation and unilateral mandibular distraction with transarch elastic traction in HFM patients.

The purpose of this study was to investigate the effect of the number and the geometry of resorbable screws (RSs; Inion CPS System; Inion Ltd, Tampere, Finland) on the biomechanical stability of the in vitro model with sagittal split ramus osteotomy. The sagittal split ramus osteotomy polyurethane hemimandible (Synbone, Malans, Switzerland) was fixed by 7 osteosynthesis methods after 5 mm advancement of the distal segment (n = 5 for each method): 1TP (1 titanium miniplate and 4 screws), 3RL (3 RSs with linear configuration at the retromolar area [RMA]), 2R1B (2 RSs at RMA and 1 RS at the mandibular body [MB]), 2R1A (2 RSs at the RMA and 1 RS at the mandibular angle [MA]), 3R1B (3 RSs at RMA and 1 RS at the MB), 3R1A (3 RSs at RMA and 1 RS at the MA), and 3R1A1B (3 RSs at the RMA, 1 RS at the MA, and 1 RS at the MB). Values of linear compressive load were measured at 1- to 5-mm displacement of the lower first molar with a 1-mm interval and were statistically analyzed. From 1- to 5-mm displacement, there were significant differences in load values among groups (P < 0.05, P < 0.01, P < 0.01, P < 0.001, and P < 0.001, respectively). When the amount of displacement was increased, the difference in load values between 1TP, 3RL, and 2R1B became significantly prominent. There was a significant difference in total load values according to number and geometry of RSs (P < 0.001). All kinds of geometry with more than 3 RSs were more rigid than 1TP. The 3R1A1B method showed better biomechanical stability than 1TP, 3RL, and 2R1B. In 3 RS and 4 RS groups, fixation in MA (2R1A, 3R1A) exhibited a tendency of better stability than fixation in MB (2R1B, 3R1B). Fixation with 2R1A could provide better biomechanical stability than 1TP and similar rigidity with 3R1A1B.

The purpose of this study was to present a new approach for establishing the customized occlusal plane for an individual patient in systemized surgical treatment objective of class III cases. After the correction of incisor inclination to occlusal planes (U1-MxOP and L1-MnOP), the intermaxillary relationship can be established with normal overbite/overjet and maximum intercuspation. The anterior limits of the maxilla and the mandible can be positioned according to A to N perpendicular, Frankfort horizontal (FH) to AB plane angle, and upper incisor display. The vertical level of the upper first molar can then be determined in relation to the Y plane (an imaginary arch drawn using the distance between the lower incisor edge point and the rotation center point of the condylar head as a radius) and a triangle projected by the upper and lower limits of the FH to the occlusal plane (FH-OP triangle). Soft-tissue facial balance can be checked with the lip/chin projection in relation to the true vertical line at subnasale and the lower third facial height ratio. Appropriate superior impaction of the posterior part of the maxilla in relation to the Y plane and FH-OP triangle in case 1 produced significant improvement of the facial profile and occlusion. However, case 2 showed that the amount of superior impaction of the posterior part of the maxilla was not enough to produce a significant setback of the mandible and retraction of the lip and chin. The systemized surgical treatment objective flowchart that could set the customized occlusal plane for an individual patient might provide a useful guideline for obtaining optimal aesthetics and functional occlusion in class III cases.

Purpose: We classified the outcomes of non-trapdoor-type blowout fracture repair by surgical indications and then compared the outcomes according to the time of treatment., Methods: The medical records of 591 patients with orbital fractures that were treated surgically within 30 days of trauma were included in the study. The enrolled patients were classified into 2 groups by the major surgical indications: 1 group included patients with diplopia or limited extraocular motion, and the other group of patients had significant enophthalmos (>2 mm) or a large fracture on computed tomography (>½). The clinical outcomes were compared between the patients who received surgical repair within 14 days of trauma (early) and those who received treatment from 15 to 30 days after the trauma (delayed) in each group., Results: Two hundred thirty-three patients received surgical repair because of diplopia or limited extraocular motion. Both the early repaired group (n = 195) and the delayed repaired group (n = 38) showed significant improvement after surgeries. The degree of preoperative and postoperative diplopia and limited extraocular motion was not associated with differences between the 2 groups. Four hundred one patients received surgical repair because of enophthalmos (>2 mm) or a large fracture on computed tomography (>½). Both the early repaired group (n = 328) and the delayed repaired group (n = 73) showed significant improvement of the enophthalmos after surgeries. The degree of preoperative/postoperative enophthalmos did not show differences between the 2 groups., Conclusions: If the blowout fracture repairs were performed within a month, the surgical outcomes did not differ according to the time of surgery in the cases of nontrapdoor blowout fracture.