Maxillary Corticotomies With Bone-to-Bone Retraction and Mandibular Segmental Osteotomy for Correcting an Anterior Double Protrusion.

BACKGROUNDS: This article presents maxillary corticotomies with bone-to-bone retraction and anterior segmental osteotomy (ASO) as an alternative to 2-jaw orthognathics in the bimaxilary protrusion patient with partially anchylosed maxillary anterior tooth. METHODS: The 18-year-old male, complaining of anterior protrusion, with a trauma history to the maxillary central incisor, and requesting rapid treatment, was treated with maxillary corticotomies in 2 stages and ASO in the mandible. The mandibular ASO and palatal corticotomy were done under local anesthesia and 2 weeks later, labial corticotomy followed. The anterior segment was retracted bodily using buccal C-tubes and a combination of the C-lingual retractor and palatal C-plate. RESULTS: Due to a concern about ankylosis of the maxillary right central incisor, retraction of the anterior bone/tooth segment was chosen over any attempt to move teeth through the bone. After bone-to-bone retraction, the remaining extraction space was closed by protraction of posteriors. The total treatment period was 18 months. There was good retraction of the anterior segment and retrusion of the lips. CONCLUSIONS: A combination of maxillary corticotomies with skeletal anchorage for bone-to-bone retraction and a mandibular ASO under local anesthesia might be an alternative treatment option for excellent profile change in a short treatment period.

Wide Linear Corticotomy and Anterior Segmental Osteotomy Under Local Anesthesia Combined Corticision for Correcting Severe Anterior Protrusion With Insufficient Alveolar Housing.

BACKGROUNDS: This article presents an alternate surgical treatment method to correct a severe anterior protrusion in an adult patient with an extremely thin alveolus. To accomplish an effective and efficient anterior segmental retraction without periodontal complications, the authors performed, under local anesthesia, a wide linear corticotomy and corticision in the maxilla and an anterior segmental osteotomy in mandible. METHODS: In the maxilla, a wide linear corticotomy was performed under local anesthesia. In the maxillary first premolar area, a wide section of cortical bone was removed. Retraction forces were applied buccolingually with the aid of temporary skeletal anchorage devices. Corticision was later performed to close residual extraction space. In the mandible, an anterior segmental osteotomy was performed and the first premolars were extracted under local anesthesia. RESULTS: In the maxilla, a wide linear corticotomy facilitated a bony block movement with temporary skeletal anchorage devices, without complications. The remaining extraction space after the bony block movement was closed effectively, accelerated by corticision. In the mandible, anterior segmental retraction was facilitated by an anterior segmental osteotomy performed under local anesthesia. Corticision was later employed to accelerate individual tooth movements. CONCLUSIONS: A wide linear corticotomy and an anterior segmental osteotomy combined with corticision can be an effective and efficient alternative to conventional orthodontic treatment in the bialveolar protrusion patient with an extremely thin alveolar housing.

Double Anterior Segmental Osteotomy Under Local Anesthesia for Correcting Adult Protrusion With Thin Alveolus and Ankylosed Tooth.

BACKGROUNDS: This paper describes an additional benefit in double anterior segmental osteotomy to correct severe anterior protrusion in adult patients with extremely thin mandibular alveolus and ankylosed tooth. For the optimal anterior segmental retraction, an ankylosed posterior tooth needed surgical inclination reposition. During anterior segmental osteotomy surgery under local anesthesia, additional single tooth osteotomy was performed without challenge. METHODS: For anterior segment retraction, osteotomy cuts were made by the surgeon to define a block of bone embedding 6 mandibular anterior teeth. First premolars were extracted during initial orthodontic treatment period. But the ankylosed lower left lateral incisor and lower right second premolar root which remains mesially with uprighted crown hindered further anterior segment retraction. The authors removed cortical bone around second premolar root and repositioned to be upright. Anterior segment was retracted to proper position utilizing the space gained. RESULT: Thin alveolar mandibular anterior segment retraction and the second premolar uprighting were managed effectively with additional single tooth segmental osteotomy during anterior segmental osteotomy. CONCLUSION: Double anterior segmental osteotomy can be an effective alternative to conventional orthognathic surgery in selected adult patients.

Single-Tooth Osteotomy Combined Wide Linear Corticotomy Under Local Anesthesia for Correcting Anterior Protrusion With Ectopically Erupted Canine.

BACKGROUNDS: This article presents the alternative surgical treatments of both anterior protrusion by carrying out retraction on mandibular anterior fragment, meanwhile applying retraction force on maxilla anterior teeth and ectopically erupted canine with using platelet-rich fibrin (PRF). METHODS: Anterior segmental osteotomy was combined with linear corticotomy under local anesthesia. The correction of right ectopic canine was achieved through 2 stages. First, dento-osseous osteotomy on palatal side was performed. Then second osteotomy with immediate manual repositioning of the canine with concomitant first premolar extraction was enhanced with PRF, which was prepared by centrifuging patient's blood, applied into buccal side of high canine during osteotomy. Mandibular retraction was accomplished by anterior segmental osteotomy. RESULTS: Single-tooth osteotomy is a more effective surgical method for ankylosed or ectopically erupted tooth in orthodontic treatment. It can reduce the total orthodontic treatment time and root resorption, 1 common complication. Significant improved bone formation was seen with the addition of PRF on noncritical size defects in the animal model. It is reasonable to think that PRF can promote bone regeneration. So early bone formation also can reduce the complication such as postoperative infection. CONCLUSIONS: As an alternative to anterior protrusion and ectopically erupted canine treatment, segmental osteotomy and corticotomy combined platelet-rich plasma can enhance orthodontic treatment outcome.

Stability of Modified Maxillomandibular Advancement Surgery in a Patient With Preadolescent Refractory Obstructive Sleep Apnea.

Maxillomandibular advancement (MMA) surgery can be considered a primary single-stage treatment for improving the quality of life in patients with preadolescent refractory obstructive sleep apnea (OSA). The aim of the present report was to evaluate the treatment efficacy and stability of modified MMA surgery in a growing patient with morbidly severe symptoms and medical complications. Using the follow-up results from the questionnaire, polysomnography, 2-dimensional cephalometry, and 3-dimensional cone-beam computed tomography measurements, the success of modified MMA surgery was assessed in terms of the postoperative improvements of functions and esthetics and postretentive stability of the improvements throughout the growth period. The present report provides some clinical recommendations when considering skeletal surgery in preadolescent patients with OSA: 1) the decision criteria of MMA surgery as definite treatment; 2) the proper surgical design for both maximum enlargement of the airway and esthetic improvement; and 3) the postoperative facial growth for long-term stability of airway function and skeletal improvement. With a systematic multidisciplinary approach, early surgical intervention can be used to treat OSA in children successfully and permanently.

Differences in bone remodeling using demineralized bone matrix in bilateral sagittal split ramus osteotomy: a study on volumetric analysis using three-dimensional cone-beam computed tomography.

PURPOSE: The aim of this study was to examine the effects of demineralized bone matrix (DBM) grafts on bone remodeling during sagittal split ramus osteotomy by measuring 3-dimensional (3D) reconstructed images. PATIENTS AND METHODS: Forty-eight patients were selected for this study. In the control group, no grafts were performed. In the DBM group, DBX grafts were placed between the proximal and distal segments. Three-dimensional cone-beam computerized tomographic (3D-CBCT) images were obtained within 1 week, after 3 months (T2), and after 6 months (T3) postoperatively. By measuring the total skeletal volume from the right condylar head to the right mandibular first molar, the volume of the graft site was measured indirectly. Using the data thus obtained, a volume-increasing ratio (percentage) was computed. SimPlant analytical software was used to analyze the 3D reconstructed volumes. RESULTS: The 2 groups showed a significant increase in volume. However, in the same period, the volume-increasing ratios of the 2 groups showed significant differences. In the control group, a significant increase in volume was seen until T2, after which a negligible increase was seen. Conversely, in the DBM group, a significant volume increase continued until T3. CONCLUSION: In orthognathic surgeries, grafting using DBM is a favorable procedure that accelerates bone formation. Therefore, in cases with inevitable large bony gaps, DBM grafts can play a positive role in the stable healing of segments and the prevention of postoperative complications. Moreover, because volumetric analysis using 3D-CBCT analyzing software is a fast and simple method, future studies using this technique are expected to increase.

Correction of facial asymmetry and maxillary canting with corticotomy and 1-jaw orthognathic surgery.

Although 2-jaw orthognathic surgery is a typical recommendation for the treatment of facial asymmetry, another good treatment alternative is maxillary corticotomy with temporary skeletal anchorage devices followed by mandibular orthognathic surgery. The corticotomy procedure described here can achieve unilateral molar intrusion and occlusal plane canting correction with potentially fewer complications than 2-jaw orthognathic surgery. The approach allows movement of dentoalveolar segments in less time than with conventional dental intrusion using temporary skeletal anchorage devices. A 2-jaw asymmetry with occlusal plane canting might be corrected using maxillary corticotomy and mandibular orthognathics rather than 2-jaw orthognathics. Two patients with facial asymmetry are presented here. In each one, the maxillary cant was corrected over a period of 2 to 3 months with 3.5 mm of intrusion of the unilateral buccal segment. After the preorthognathic cant correction, orthognathic surgery was done to correct the mandibular asymmetry.

The Efficacy of the Partial Glossectomy for Prevention of Airway Volume Reduction in Orthognathic Surgery of Class III Patients.

The aim of this study was to evaluate the effects of a partial glossectomy on volumetric changes of pharyngeal airway space (PAS) in patients with mandibular setback surgery. Overall, 25 patients showing clinical features related to macroglossia treated with mandibular setback surgery were included in this retrospective study. Subjects were divided into two groups: the control group (G1, n = 13, with BSSRO) and the study group (G2, n = 12, with both BSSRO and partial glossectomy). The PAS volume of both groups was measured by the OnDemand 3D program on CBCT taken shortly before operation (T0), 3 months post-operative (T1), and 6 months post-operative (T2). A paired t-test and repeated analysis of variance (ANOVA) were used for statistical correlation. Total PAS and hypopharyngeal airway space were increased after operation in Group 2 compared to Group 1 (p < 0.05), while oropharyngeal airway space showed no significant statistical difference with the tendency of increasing. The combination of partial glossectomy and BSSRO surgical techniques had a significant effect on increasing the hypopharyngeal and total airway space in class III malocclusion patients (p < 0.05).

Implant placement with inferior alveolar nerve repositioning in the posterior mandible.

This case report presents inferior alveolar nerve (IAN) repositioning as a viable approach for implant placement in the mandibular molar region, where challenges of severe alveolar bone width and height deficiencies can exist. Two patients requiring implant placement in the right mandibular molar region underwent nerve transposition and lateralization. In both cases, inadequate alveolar bone height above the IAN precluded the use of short implants. The first patient exhibited an overall low alveolar ridge from the anterior to posterior regions, with a complex relationship with adjacent implant bone level and the mental nerve, complicating vertical augmentation. In the second case, although vertical bone resorption was not severe, the high positioning of the IAN within the alveolar bone due to orthognathic surgery raised concerns regarding adequate height of the implant prosthesis. Therefore, instead of onlay bone grafting, nerve transposition and lateralization were employed for implant placement. In both cases, the follow-up results demonstrated successful osseointegration of all implants and complete recovery of postoperative numbness in the lower lip and mentum area. IAN repositioning is a valuable surgical technique that allows implant placement in severely compromised posterior mandibular regions, promoting patient comfort and successful implant placement without permanent IAN damage.

Postoperative stability of 2-jaw surgery with clockwise rotation of the occlusal plane.

OBJECTIVE: The objective of this study was to investigate the skeletal stability after Le Fort I osteotomy with clockwise rotation and bilateral sagittal split osteotomy. MATERIALS AND METHODS: The sample consisted of 31 young Korean patients who were treated with Le Fort I osteotomy with clockwise rotation and setback bilateral sagittal split osteotomy. The lateral cephalographs were obtained before surgery (T1), right after surgery (T2), and on an average of 6.23 months after the operation (T3). The horizontal and vertical relations of landmarks to the reference line and soft tissue changes were evaluated. RESULT: During the T2 - T1 period, there was superior and anterior movement of the posterior part (PNS, UMD) and advancement and impaction of the anterior part (ANS, A point, UIE) of the maxilla. The mandible was moved superiorly and posteriorly. During the T3 - T2 period, maxillary segment showed counterclockwise rotational relapse. The posterior part was relatively stable especially in the vertical position and the anterior part moved in the posterior and superior directions. Mandibular landmarks showed forward relapse in the horizontal aspect and superior relapse in the vertical aspect. The posterior part (PNS and UMD) showed a significantly higher stability rate (>70%) in the vertical aspect and the anterior part of the maxilla (ANS, A point) demonstrated a significantly lower value (<30%) in the vertical aspect. According to the skeletal changes, the soft tissue of the lower facial profile is rotated clockwise. CONCLUSIONS: Two-jaw surgeries involving clockwise rotation of the occlusal plane showed stable results especially in the maxillary posterior landmarks. The clockwise rotational movement can be beneficial to increase skeletal stability and facial aesthetics in Asians.

Sinus mucosal healing pattern according to pterygomaxillary disjunction type after Le Fort I osteotomy.

Objectives: During Le Fort I osteotomy, the separation of the pterygomaxillary junction (PMJ) is a difficult procedure for most surgeons because it is invisible. In this process, damage to the posterior structures constituting the sinus or those adjacent to it, including the maxillary sinus posterior wall and pterygoid plate, may occur. We would like to investigate the effects of this on the inside of the maxillary sinus after surgery and whether there are complications. Materials and Methods: One-hundred patients who underwent Le Fort I osteotomy from 2013 to 2020 using cone-beam computed tomography images were classified into two groups (clean-cut type and fractured type) according to the PMJ cutting pattern. In addition, the mucosal thickness in the maxillary sinus was divided into preoperative, postoperative three months, one year, and the change over the course of surgery was evaluated retrospectively. Results: Of the total 100 cases, the clean-cut type numbered 28 cases and the fractured type totaled 72 cases. Among the fracture types, part of the sinus wall and the pterygoid plate were broken in 69 cases, and the maxillary sinus posterior wall was detached in three cases. There was no statistically significant difference in sinus mucosal thickening between the clean-cut type and fractured type of the PMJ, three months and one year after surgery between the two groups. However, there was a significant difference in sinus mucosal thickness at postoperative one year in the case where a partial detachment of the maxillary sinus posterior wall occurred compared to not. Conclusion: Even if there is some damage to the structures behind the PMJ, it may not be reasonable to spend some time on the PMJ separation process considering the overall postoperative complications, if there is no significant difference inside the sinus, or increased probability of postoperative complications.

Retrospective clinical study of mandible fractures.

BACKGROUND: As society becomes more complex, the incidence of mandibular fractures is increasing. This study aimed to analyze the incidence and type and identify etiological factors of mandibular fractures to use them in future treatments. MATERIAL AND METHODS: Data were collected from 224 patients who visited the department of oral and maxillofacial surgery at the Kyung Hee Medical Center dental hospital during a 6-year period (2016 to 2021). A logistic regression model was used for data analysis. RESULTS: In a total of 224 patients, 362 fractures were appeared. The average age of the patients was 34.1 years, with the highest incidence in the 20s. And the ratio between male and female was 4.09:1. Symphysis fractures were the most prevalent of all patients (52.7%), followed by unilateral condyle (37.1%), angle (36.2%), bilateral condyle (9.4%), body (8%), and coronoid (2.2%). The most common cause of fracture was daily-life activity (57.6%), followed by violence (30.4%), traffic accidents (8.5%), and syncope (3.6%). Patients with symphysis fracture were at low risk (OR < 1) of angle, body, and unilateral condyle fractures. Similarly, patients with unilateral fracture were at low risk (OR < 1) of symphysis, angle, body, and others site fractures. In contrast, patient with bilateral condyle fracture were at high risk (OR > 1) of coronoid fractures. And younger patients were high risk of mandibular angle fractures. CONCLUSION: Through this study, it was confirmed that etiological factors of mandibular fractures were like those of previous studies.

Analysis of digitalized panorama and cone beam computed tomographic image distortion for the diagnosis of dental implant surgery.

OBJECTIVES: To evaluate the tooth image measurements according to the tooth location and to calculate the magnification rate for comparison and analysis in digitalized panoramic and cone beam computed tomographic (CBCT) images. METHODS: A diagnostic template was fabricated and delivered on the preimplant sites. A 5-mm gutta-percha cone or a metal ball was inserted in the coronal part of each tooth. Panoramic images were obtained with Ortho stage (AUTO III N CM; Asahi, Japan) or Promax (Planmeca, Helsinki, Finland) and CBCT images were obtained with PANORAMIC CT (PSR9000N; Asahi) for each patient and the same region. The vertical length of the gutta-percha cone or the metal ball was measured and compared with the panoramic and CBCT images according to the tooth location. Magnification rate was compared between the 2 types of panoramic machines. RESULTS: About 1.09 to 1.28 magnification occurred in panoramic images, depending on the tooth location. The magnification rate was significantly different between the panoramic machines (Ortho stage, 1.27; Promax. 1.17). Almost no magnification of images occurred in CBCT images with no difference to the tooth location. CONCLUSIONS: In panoramic radiography, it is inappropriate to apply a general magnification ratio covering the whole image. For a more accurate implant surgery, the use of a metal ball or a premeasured gutta-percha cone on the preimplant site as standard measurement is recommended. However, in recently introduced CBCT, magnification of images did not occur, allowing it being used for accurate clinical procedures.

Posterior bending osteotomy: An effective measure to secure facial symmetry in orthognathic surgery.

This study aimed to compare the effectiveness of posterior bending osteotomy and grinding techniques for orthognathic surgery in patients with facial asymmetry. Patients who had undergone Le Fort I osteotomy and bilateral sagittal split ramus osteotomy, and who presented with a menton shift and setback difference exceeding 4 mm, were enrolled. Cone-beam computed tomography was performed before surgery (T0), immediately after surgery (T1), and 6 months after surgery (T2). Overall, 38 patients were included and divided into posterior bending osteotomy (n = 23) and grinding (n = 15) groups. Significant differences were observed between the posterior bending osteotomy and grinding groups on the treated side. In the grinding group, the gonion on the treated side was displaced slightly outward, resulting in a significant difference between both sides (non-treated side: 50.52 ± 4.20 [T0] and 48.67 ± 4.37 [T2]; treated side: 50.88 ± 4.55 [T0] and 51.00 ± 3.95 [T2]; p = 0.038). In the posterior bending osteotomy group, bilateral inward movements of the gonion were observed, and the distance from the midsagittal plane to the gonion did not differ significantly between the sides (non-treated side: 46.74 ± 4.41 [T0] and 45.54 ± 3.95 [T2]; treated side: 47.43 ± 4.93 [T0] and 45.18 ± 3.52 [T2]; p = 0.224). The yawing movement of the proximal segment was greater in the grinding group than in the posterior bending osteotomy group (non-treated side: p = 0.839; treated side: p = 0.025). Posterior bending osteotomy is recommended over the grinding method for patients with severe facial asymmetry, in order to ensure a symmetric and esthetic facial profile by allowing passive adaptation between the mandibular segments.

Removal of a suture needle: a case report.

BACKGROUND: Foreign bodies may be embedded or left behind in the oral cavity during oral surgical procedure. The loss of instruments such as impression material, surgical gauze, and broken injection needles are commonly reported in the dental field. These complications are generally symptomatic and show signs of inflammation, pain, and purulent discharge. Accidental breakage of suture needles is a rare but potentially dangerous event. CASE PRESENTATION: In this report, we present one case of lost suture needle during the procedure of flap operation at local dental clinic and its successful removal under local/general anesthesia administration via CBCT with a help of two reference needles to localize the 6-0 nylon needle and consulting with the clinician. CONCLUSION: CT scanning taken while mouth-closing may not be accurate with regard to real location measurement performed while mouth-opening. If so, other up-to-date radiographic devices and methods to retrieve a needle are recommended.

Study of soft tissue changes in the upper lip and nose after backward movement of the maxilla in orthognathic surgery.

OBJECTIVES: This study evaluates soft tissue changes of the upper lip and nose after maxillary setback with orthognathic surgery such as Le Fort I or anterior segmental osteotomy. MATERIALS AND METHODS: All 50 patients with bimaxillary protrusion and skeletal Class II malocclusion underwent Le Fort I or anterior segmental osteotomy with backward movement. Soft and hard tissue changes were analyzed using cephalograms collected preoperatively and 6 months postoperatively. RESULTS: Cluster analysis on the ratios shows that 2 lines intersected at 4 mm point. Based on this point, we divided the subjects into 2 groups: Group A (less than 4 mm, 27 subjects) and Group B (more than 4 mm, 23 subjects). Also, each group was divided according to changes of upper incisor angle (≥4°=A1, B1 or <4°=A2, B2). The correlation between A and B groups for A'/ANS and Ls/Is (P<0.001) was significant; A'/A (P=0.002), PRN/A (P=0.043), PRN/ANS (P=0.032), and St/Is (P=0.010). Variation of nasolabial angle between the two groups was not significant. There was no significant correlation of vertical movement and angle variation. CONCLUSION: The ratio of soft tissue to hard tissue movement depends on the amount of posterior movement in the maxilla, showing approximately two times higher rates in most of the midface when posterior movement was greater than 4 mm. The soft tissue changes caused by posterior movement of the maxilla were little affected by angular changes of upper incisors. Interestingly, nasolabial angle showed a different tendency between A and B groups and was more affected by incisal angular changes when horizontal posterior movement was less than 4 mm.

Closure of oroantral fistula: a review of local flap techniques.

Oroantral fistula (OAF), also termed oroantral communication, is an abnormal condition in which there is a communicating tract between the maxillary sinus and the oral cavity. The most common causes of this pathological communication are known to be dental implant surgery and extraction of posterior maxillary teeth. The purpose of this article is to describe OAF; introduce the approach algorithm for the treatment of OAF; and review the fundamental surgical techniques for fistula closure with their advantages and disadvantages. The author included a thorough review of the previous studies acquired from the PubMed database. Based on this review, this article presents cases of OAF patients treated with buccal flap, buccal fat pad (BFP), and palatal rotational flap techniques.

Speedy surgical orthodontic treatment with skeletal anchorage in adults--sagittal correction and open bite correction.

PURPOSE: The present report describes a new type of corticotomy-assisted orthodontic treatment called Speedy orthodontics, which allows faster movements of the dental segments using skeletal anchorage. MATERIALS AND METHODS: To minimize the risk of necrosis, 2 procedures are performed. During the initial surgery, bilateral and horizontal corticotomies are performed in the palatal area with the patient under local anesthesia. After 2 to 3 weeks, a second buccal corticotomy is performed and 500 to 900 g of force per side is immediately applied to the corticotomized segment. RESULTS: Successful alveolar bone bending can be obtained in cases of adult protrusion or open bite. CONCLUSIONS: Speedy orthodontics allows for more precise control of anterior segment retraction in adult protrusion patients and can be used for posterior segment intrusion. This technology is powerful, easy to apply, and provides a significant advance in surgical orthodontics.

Speedy surgical-orthodontic treatment with temporary anchorage devices as an alternative to orthognathic surgery.

INTRODUCTION: We describe a new type of corticotomy-assisted orthodontic treatment called speedy orthodontics for treating severe anterior protrusion in adults. Once medullary bone is deformed after corticotomy, recovery to its original dimension is impossible if the greenstick fractured bone is ossified as it was deformed. Speedy orthodontics describes a protocol to allow movement of dental segments over a shorter time by using a corticotomy and an orthopedic force with temporary anchorage devices. METHODS: After proper diagnosis and treatment planning, the maxillary first premolars are removed, and then a corticotomy is performed to outline a block of bone around the maxillary anterior teeth under local anesthesia. An interval of 2 weeks is optimal between the labial and lingual corticotomy for sufficient healing and less patient anxiety. The maxillary anterior teeth are fixated into a single unit with the specially designed lingual retractor. A retraction force of 500 to 900 g per side is applied to the lingual retractor and the C-palatal plate placed in the midpalatal area. After anterior bone segment retraction, finishing is performed with full fixed appliances. RESULTS: Correct overbite and overjet, facial balance, and improvement of lip protrusion were obtained in adults with protrusion treated by speedy orthodontics. CONCLUSIONS: This new type of treatment mechanics can be an effective alternative to orthognathic surgery in adults with protrusion.

Comparison between anterior segmental osteotomy versus conventional orthodontic treatment in root resorption: a radiographic study using cone-beam computed tomography.

BACKGROUND: Patients who received orthodontic treatment are likely to have apical root shortening. It appears that external apical root resorption results from a combination of patient-related risk factors such as genetic influences, systemic factors, and orthodontic treatment-related factors. Regarding the fact that the anterior segmental osteotomy (ASO) has been known for its possibility of complementing external apical root resorption and of buffering periodontal problems, it has been the preferred treatment. However, the studies on the efficacy of ASO in preserving the root are not sufficient. In this study, we compared the amount of root resorption between the patients who only received orthodontic treatment and the patients who received orthodontic treatment with ASO. METHODS: This study included 28 patients (the number of incisor = 198) who received orthodontic treatment with or without ASO. We categorize them into groups A and B by the type of orthodontic treatment (group A: conventional orthodontic treatment; group B: orthodontic treatment with ASO). Cone-beam computed tomographic and cephalometric evaluations were retrospectively performed on the radiographs taken for the diagnosis of the treatment before treatment and at the end of active treatment. RESULTS: In group B, root resorption itself and its rate both turned out to have significantly lower than those in group A. Also, the change of incisal angle is significantly smaller in group B than in group A. On the other hand, in group A, the change of incisal angle was positively correlated with the change of AP (anteroposterior) position. In group B, the change of incisal angle was negatively correlated with the duration of the orthodontic treatment. In group B, amount of root resorption (mm) was positively correlated with the duration of the orthodontic treatment. CONCLUSIONS: The results show lesser root resorption and shorter treatment duration with ASO than with conventional orthodontic treatment. Therefore, if the indications are accurately determined, ASO can be an effective treatment option when the amount of root resorption is expected to be high, especially in late adults.