The purpose of this study was to evaluate the surgical movement and postoperative orthodontic treatment (POT) of the surgery-first approach for the correction of skeletal class III malocclusion. The samples consisted of 11 patients with skeletal class III malocclusion who underwent nonextraction treatment and 2-jaw surgery (Le Fort I osteotomy impaction of the posterior maxilla, IPM; bilateral sagittal split ramus osteotomy setback of the mandible). The wafer was removed 4 weeks after surgery. Mean (SD) durations of POT and total treatment were 8.91 (3.14) and 12.18 (3.57) months, respectively. Lateral cephalograms were obtained during the initial examination (T₀), immediately after surgery (T₁), and after debonding (T₂). Sixteen variables were measured. Paired t-test was performed for statistical analysis. The maxilla rotated clockwise, and the nasolabial angle increased by IPM (FH-palatal plane angle, FH-occlusal plane angle, P < 0.01; nasolabial angle, P < 0.05) and well maintained during POT. The mandible was repositioned backward by bilateral sagittal split ramus osteotomy setback of the mandible (SNB, Pog-N perp, P < 0.001) and relapsed forward during POT (SNB, P < 0.01; Pog-N perp, P < 0.05). U1-SN decreased by IPM (P < 0.001) and relapsed labially owing to class III mechanics during POT (P < 0.01); eventually, no significant difference was found between T₀ and T₂ stages. Although IMPA increased by POT, there was no significant difference between T₀ and T₂ stages. The mandible seems to relapse forward immediately after wafer removal and before labioversion of the lower incisors. Accurate prediction of POT is crucial in controlling dental alignment, incisor decompensation, arch coordination, and occlusal settling. Long-term wearing and selective grinding of the wafer for labioversion of the lower incisors and use of miniplates/miniscrews to control the inclination of the upper incisor and to prevent relapse of the mandible are needed.

Objective: To present cleft patients treated with protraction facemask and miniplate anchorage (FM/MP) in order to demonstrate the effects of FM/MP on maxillary hypoplasia. Materials and Methods: The cases consisted of cleft palate only (12 year 1 month old girl, treatment duration = 16 months), unilateral cleft lip and alveolus (12 year 1 month old boy, treatment duration = 24 months), and unilateral cleft lip and palate (7 year 2 month old boy, treatment duration = 13 months). Curvilinear type surgical miniplates (Martin, Tuttlinger, Germany) were placed into the zygomatic buttress areas of the maxilla. After 4 weeks, mobility of the miniplates was checked, and the orthopedic force (500 g per side, 30° downward and forward from the occlusal plane) was applied 12 to 14 hours per day. Results: In all cases, there was significant forward displacement of the point A. Side effects such as labial tipping of the upper incisors, extrusion of the upper molars, clockwise rotations of the mandibular plane, and bite opening, were considered minimal relative to that usually observed with conventional protraction facemask with tooth-borne anchorage. Conclusions: FM/MP can be an effective alternative treatment modality for maxillary hypoplasia with minimal unwanted side effects in cleft patients.

Orthognathic surgery is an effective surgical method to achieve functionality and facial esthetics for mandibular prognathism. If surgery is performed with a conventional method, errors may occur in the surgical preparation process and the surgical procedures, and there is a limitation in that the accuracy of surgery is determined according to the surgeon’s experience and tactual sense. However, with the recent development of three-dimensional (3D) virtual planning and CAD/CAM technology, more 3D and predictable surgical planning and more accurate and time-saving surgery have become possible. The purpose of this study is to evaluate the surgical accuracy of 3D Virtual Surgery, CAD/CAM-Assisted Orthognathic surgery for Skeletal Class III Patients. The study included 18 patients who had undergone orthognathic surgery for skeletal class III malocclusion from January 2020 to December 2021. To evaluate the accuracy of the virtual planning, 3D facial cone-beam computed tomography taken immediately after surgery (T1) and virtual surgery data (Tv) were superimposed in each patient. Landmarks were set on each of the maxillary segment, mandibular distal segment, and left and right mandibular proximal segment, and the difference between T1 and Tv was compared 3D on the x, y, and z-axis. (ΔT: T1−Tv). As a result, the average distance between Tv and T1 at each landmark, all landmarks except for the posterior nasal spine of the maxillary segment showed <1 mm. In particular, the differences across the x and z-axis were very small, while the difference across the y-axis tend to be large. The comparison of the position of each segment in virtual surgery and actual surgery was as follows. It can be seen that all segments were located slightly downward, and the medial pole of the mandibular proximal segment was located posterolateral and the lateral pole was located anteromedial after the actual surgery compared with the virtual planning. It means that the proximal segment was slightly rotated, but the difference was within 1 mm, so it can be considered that the surgery was accurate. Base on this study, orthognathic surgery using 3D virtual surgery planning and CAD/CAM technologies was very accurate. By applying these cutting-edge technologies to clinical practice, it was possible not only to increase the predictability of surgery but also to improve the convenience of surgery. Therefore, it is thought that it will be important for clinicians to make continuous efforts to applicate cutting-edge technologies to be developed in the future to patient diagnosis and surgery.

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 evaluate the stress distribution of resorbable screw (RS) and cortical/cancellous bone in the mandibular setback surgery with bilateral sagittal split ramus osteotomy (BSSRO) according to fixation geometry and number of RSs using three-dimensional finite element analysis. Three-dimensional virtual models of the mandible and bicortical RS (INION CPS System; diameter, 2.5 mm; length, 12 mm [Inion Ltd, Tampere, Finland]) were constructed by Mimics (Materialise, Ann Arbor, MI) using three-dimensional computed tomography DICOM data with 0.5-mm-thickness cut. After 8-mm setback BSSRO was performed, fixation between the proximal and distal segments of the mandible was done with bicortical RS. Fixation options were classified into 3RL (3 RSs with linear configuration at the retromolar area), 2R1A (2 RSs at the retromolar area and 1 RS at the mandibular angle area), 2R1B (2 RSs at the retromolar area and 1 RS at the mandibular body area), and 3R1A (3 RSs at the retromolar area and 1 RS at the mandibular angle area). After applying the occlusal load of 132 N on the lower first molar, stress distributions of the RSs and cortical/cancellous bone in each option were analyzed by ANSYS program (ANSYS Inc, Canonsburg, PA). Maximum stress concentration was found at the anterior RS fixation in the retromolar area in all options. Although 3R1A fixation showed more even distribution of stress concentration than other fixation options, 2R1A fixation was comparable with 3R1A fixation in view of yield stress in RSs. In terms of fixation geometry and number of RSs, both 2R1A and 3R1A fixation configurations might provide proper stress distribution in BSSRO.

Backgrounds: The purpose of this study is to discuss the total joint reconstruction surgery for a patient with recurrent ankylosis in bilateral temporomandibular joints (TMJs) using three-dimensional (3D) virtual surgical planning, computer-aided manufacturing (CAD/CAM)-fabricated surgical guides, and stock TMJ prostheses. Case presentation: A 66-year-old female patient, who had a history of multiple TMJ surgeries, complained of severe difficulty in eating and trismus. The 3D virtual surgery was performed with a virtual surgery software (FACEGIDE, MegaGen implant, Daegu, South Korea). After confirmation of the location of the upper margin for resection of the root of the zygoma and the lower margin for resection of the ankylosed condyle, and the position of the fossa and condyle components of stock TMJ prosthesis (Biomet, Jacksonville, FL, USA), the surgical guides were fabricated with CAD/CAM technology. Under general anesthesia, osteotomy and placement of the stock TMJ prosthesis (Biomet) were carried out according to the surgical planning. At 2 months after the operation, the patient was able to open her mouth up to 30 mm without complication. Conclusion: For a patient who has recurrent ankylosis in bilateral TMJs, total joint reconstruction surgery using 3D virtual surgical planning, CAD/CAM-fabricated surgical guides, and stock TMJ prostheses may be an effective surgical treatment option.