Anterior Segmental Research Articles

Different anatomical variations in the anterior segment of the right upper lung

During a routine physical examination three years ago, a 47-year-old woman received a diagnosis of a nodule in her right upper lung. Since then, she has been regularly attending outpatient clinic appointments for follow-up. Over time, the nodule has shown gradual growth, leading to a suspicion of lung cancer. Through the use of enhanced CT imaging, a three-dimensional reconstruction was performed to examine the bronchi and blood vessels in the patient’s chest. This reconstruction revealed several variations in the anatomy of the anterior segment of the right upper lobe. Specifically, the anterior segmental bronchus (B3) was found to have originated from the right middle lung bronchus. Additionally, the medial subsegmental artery of the anterior segmental artery (A3b) and the medial segmental artery (A5) were observed to share a common trunk. As for the lateral subsegmental artery of the anterior segmental artery (A3a), it was found to have originated from the right inferior pulmonary trunk. Furthermore, the apical subsegmental artery of the apical segmental artery (A1a) and the posterior segmental artery (A2) were found to have a shared trunk.

Nasolabial soft tissue changes associated with posterior maxillary movement following anterior segmental osteotomy in skeletal Class II patients: A case series

ObjectiveThis study investigated the relationship between the external nasal morphology and hard tissue movement in patients who underwent anterior segmental maxillary osteotomy (ASMO) to correct maxillary protrusion correction. MethodsThe study enroled patients with an overjet ≥ 5 mm, and an ANB ≥ 2° who underwent ASMO with or without Le Fort I osteotomy. Linear and angular measurements were performed on computed tomography images obtained preoperatively and one year post-surgery. ResultsThe movement of the maxilla at U1 was 6.7 ± 2.9 mm backward and 1.9 ± 2.0 mm upward. Tooth axis inclination of U1 (∠U1 to FH) increased 5.5 ± 6.1°. The nasolabial angle significantly increased from 90.0 ± 16.8° to 101.0 ± 13.2°. No significant differences were observed in alar base width or nasal tip angles. The change of ∠U1 to FH and the backward movement of U1 were relevant factors influencing the change of nasolabial angle. ConclusionsThis study provides insights into the relationship between external nasal morphology and posterior movement of the anterior maxillary segment after ASMO surgery. These findings are significant for predicting post-operative patient profiles.

The surgical outcomes of anterior segmental osteotomy in Asian skeletal class II patients.

Anterior segmental osteotomy (ASO) following the surgery-first approach is a long-established treatment modality to resolve lip protrusion in patients with skeletal class II patterns. However, the indications and effectiveness of ASO still remain uncertain. The objective of this study is to investigate the effectiveness of ASO in Asian skeletal class II patients by evaluating the skeletal and soft tissue changes and analyzing pre-treatment variables that determine successful outcomes in occlusal as well as esthetic aspects. The lateral cephalograms of 44 skeletal class II patients who underwent ASO and orthodontic treatment for resolving lip protrusion were retrospectively collected. Hard and soft tissue variables of two groups, normalized (NG) and unnormalized (UNG) ANB after treatment were compared and analyzed. The rotational effect of the anterior segment on the hard and soft tissue was also investigated. ASO was successful in correcting the skeletal class II relationship and lip protrusion (ΔANB - 2.3°, 4-5mm lips retraction) in most cases. However, for patients with severely camouflaged skeletal class II incisors involving a large ANB and SNA, a large ANB still remained post-treatment. The study also found that rotation of the upper and lower anterior segments further augmented the amount of lip retraction. ASO was found to successfully correct ANB of skeletal class II patients under the following conditions (ANB 5.3° ± 1.5°, SNB 77.3° ± 4.5°, U1 to FH 115° ± 7.5, L1 to FH 48.0° ± 4.6). However, patients with larger ANB and SNA values may require bi-maxillary surgery. In addition, ASO has limitations in correcting gummy smile in cases of extreme maxillary excess. For patients requiring a large amount of lip retraction, rotation of the anterior segment may be beneficial in conjunction with bi-maxillary surgery.

An alternative method for reconstructing anterior segmental mandibulectomy defects with a plate and pectoral major muscle flap.

Reconstruction of anterior segmental mandibulectomy still remains a challenge. Osteocutaneous free flap remains the ideal choice of reconstruction because it restores cosmesis and function. The use of other locoregional flaps compromises cosmesis and function. Here, we have introduced a unique technique of reconstruction with lingual cortex mandibular plate as an alternate choice for free flap. Six patients aged 12-62 years underwent oncological resection for oral cancer which involved the anterior segment of the mandible. Following resection, they underwent lingual cortex mandibular plating with pectoralis major myocutaneous flap reconstruction. Adjuvant radiotherapy was delivered to all patients. The mean bony defect was 9.2 cm. There were no significant perioperative events related to the surgery. None required tracheostomy and all were safely extubated with no post-surgical complications. The cosmetic and functional outcomes were acceptable. Following the completion of radiotherapy with a median follow-up of 11 months, Plate exposure occurred in one patient. The technique is cheap, quick and simple, and can be effectively applied in resource-constrained and demanding situations. It is possible to consider this as an alternative treatment strategy for osteocutaneous free flap in anterior segmental defects.

Modified Cupar's method for immediate diastema closure

Anterior maxillary osteotomy or ostectomy (AMO) is a safe, reliable, and easily adaptable procedure routinely performed in orthognathic surgery for the management of the dentoalveolar segment of the anterior maxilla. The anterior segmental maxillary osteotomy was first performed in 1921 by Cohn-Stock. Several modifications were done regarding approaches for AMO; however, Cupar's method is the most preferred approach by the surgeons and in practice since several decades. A novel midline split osteotomy is performed in combination with Cupar's method for superior and posterior repositioning of anterior maxillary segment in combination with immediate closure of diastema in this case report.

A modified system for classifying the bilateral superior pulmonary veins using three-dimensional computed tomography bronchography and angiography images.

BackgroundIdentifying the distribution of pulmonary veins with three-dimensional reconstruction images is of great significance for surgical guidance. Existing models neglect the consistency of the bilateral superior pulmonary veins (SPVs) and lack a simple unified classification pattern. This study aimed to analyze the distributional features of bilateral SPVs, based on a cohort of patients undergoing CT examination.MethodsThe three-dimensional computed tomography bronchography and angiography (3D-CTBA) images of 1,520 cases were retrospectively analyzed. The reconstructed images of the right upper lobes were read in 715 cases, and left upper lobes in 805 cases. Through symmetrical analysis, the circulation of main venous branches and the spatial relationships of confluences with adjacent bronchus were compared.ResultsThe SPVs of bilateral upper lobes showed common distributional features and were divided into three main types. The central vein type, the semi-central vein type, and the non-central vein type accounted for 83.35% [596], 7.84% [56], 8.11% [58] of the 715 cases with right scanning, and 25.71% [207], 62.61% [504], 10.81% [87] of the 805 cases with left scanning, respectively. There were 5 (0.70%) cases with rare variations in the right upper lobe and 7 (0.87%) in the left upper lobe. The attribution of intersubsegmental vein in the posterior segment (V2b) and its position relative to the anterior segmental bronchus (B3) was the basis of classification in the right upper lobe, and the attribution of intersubsegmental vein in the apicoposterior segment (V1+2c) and its position relative to B3 was the basis of classification in the left upper lobe. In this classification system, the branching pattern of the intersegmental vein between the apical segment and the anterior segment (V1b) in the right upper lobe, and the intersegmental vein between the apicoposterior segment and the anterior segment (V1+ 2a) in the left upper lobe were used for subdivision.ConclusionsOur modified system had a high degree of consistency in classifying SPVs in bilateral upper lobes, thus providing guidance for preoperative and intraoperative procedures.

Axenfeld\u2010Rieger syndrome combined with a foveal anomaly in a three\u2010generation family: a case report

BackgroundAxenfeld-Rieger syndrome (ARS) is a rare autosomal dominant eye disorder that can also affect other organs of the human body. The condition is primarily characterized by the anterior segmental abnormalities of the eye. Here, we present an observational case series of a three-generation family with ARS and unexpected foveal anomaly.Case presentationA 33-year-old woman was admitted to an Ophthalmology Clinic in Bialystok for left eye congenital cataract surgery. The patient (proband) was diagnosed with visual deterioration, multiple defects of iris, corectopia, displacement of the Schwalbe’s line, and phenotypic characteristics of ARS. A perimetric examination indicated peripheral visual field loss and signs typical for glaucoma. Based on the phenotypic symptoms and genetic test, the patient was diagnosed with Axenfeld Rieger Syndrome. However, the optical coherence tomography of the macula showed foveal anomaly (absence of the physiological pit), which is not typically associated with this genetic disorder. The patient’s family history revealed that her two daughters were undergoing treatment for congenital glaucoma, and one of the daughters also had foveal anomaly the same as her mother. Interestingly, an examination of the patient’s mother showed typical phenotypic features of ARS such as a defect of the iris, posterior embryotoxon, and coloboma, as well as foveal anomaly. A genetic test confirmed PITX2 mutation in both, proband’s two daughters and mother.ConclusionsThis study highlights the occurrence of ARS with unusual ophthalmic features such as foveal anomaly (absence of the physiological pit) in a three-generation family. Although ARS is known to represent the developmental defects of the anterior segment of the eye, it is very important to perform fundus evaluation to identify associated posterior segment anomalies that may affect visual acuity. The presence of ocular defects not typically associated with ARS suggests a wide spectrum of mutations within PITX2 gene which are required to identify in order to determine genotype- phenotype correlation in ARS affected individuals.

The Envelope of Segmental Movement and Airway Changes After Mandibular Anterior Subapical Osteotomy in Skeletal Class II Protrusion Patients.

This study aimed to determine the envelope of anterior segmental movement and changes in the inferior pharyngeal airway space (IPAS) and position of the hyoid bone following mandibular anterior subapical osteotomy (ASO) under local anesthesia in skeletal Class II patients with protrusion. The subjects were 33 skeletal Class II adult patients with lip protrusion. They were treated by extraction of 4 premolars and mandibular ASO under local anesthesia. Surgical movement of mandibular anterior segment and IPAS after surgery was evaluated by mandibular superimposition using lateral cephalograms between before and immediately after surgery. The depth of osteotomy and overlapping ratio were measured. The mean retraction of the mandibular incisor was 4.04 mm at the tip and 4.29 mm at the root apex. The mean vertical movement of the mandibular incisor was 3.33 mm intrusion at the tip and 3.42 mm at the root apex. The axis of the mandibular incisor did not change significantly. Patients with deep curve of Spee showed significantly more intrusion of incisors, whereas the incisor axis became more proclined. The IPAS became narrower, and the hyoid bone moved downward after surgery. The decreased IPAS was positively correlated with retraction of root apex and proclination of the mandibular incisors. To establish precise surgical treatment objectives, a balance between the amount of intrusion and changes in axis should be sought after considering anatomical limitations. Mandibular ASO should be performed with caution in skeletal Class II patients vulnerable to airway-related problems.

Use of hyrax distractor in maxillary hypoplasia associated with cleft lip and palate patients

Context: Use of hyrax expander for palatal arch lengthening (anteroposterior) is not new, but large series with long-term follow-up is lacking. Aims: The aim of this study was to evaluate surgically assisted rapid maxillary expansion for hypoplastic maxilla, its efficacy, patient's satisfaction, and relapse rates. Settings and Design: A prospective study was done in PGD of Plastic Surgery, KGMU, Lucknow, between October 2014 and December 2015. Subjects and Methods: Fifteen patients with maxillary hypoplasia associated with cleft lip and palate underwent anterior segmental maxillary osteotomy. Distraction of anterior segment was done with a tooth-anchored hyrax expansion screw oriented in anteroposterior direction. Distraction was started on the 7th day. After desired advancement, the device was left intact for a consolidation period of 3 months and follow-up for any complication was done at the end of 6 months. Statistical Analysis Used: IBM SPSS version 20 software was used. Data expressed as number (percentage) and mean ± standard deviation, Student's t-test and ANOVA were used to compare mean between groups. Results: Bony landmarks sella–nasion–A point angle, maxillary length (ANS-PNS), mean space created on one side (mesial border of first molar to distal border of first premolar), and point A-N perpendicular improved significantly (P

Modified Rotational Anterior Segmental Osteotomy for Prevention of Common Complication (Aged Appearance).

Although anterior segmental osteotomy (ASO) is powerful procedures in treating the patient who has bimaxillary dentoalveolar protrusion, there is significant change in all soft and hard tissue parameters. Soft tissue changes in response to ASO can have a deleterious effect of an aged appearance. To prevent this aged appearance, the authors tried to rotate the maxillary anterior segment rather than simply posteriorly translating the segments. The application of a clockwise pivot rotation method during ASO can prevent overcorrection by controlling the degree of setback of the piriform aperture, and it can also affect convexity of the facial profile.

Efficacy of Maxillary Anterior Segmental Distraction Osteogenesis in Patients With Cleft Lip and Palate.

To evaluate the effects of maxillary anterior segmental distraction osteogenesis (MASDO) in patients with cleft lip and palate (CLP) and to identify risk factors for increased relapse. A retrospective study. Thirty-one Japanese patients with CLP who underwent MASDO were eligible for study inclusion. We evaluated lateral cephalograms obtained before (T1), at 3 months (T2), and at 1 year (T3) after MASDO, and measured changes from T1 to T2 (δT1T2), from T2 to T3 (δT2T3), and from T1 to T3 (δT1T3). We also evaluated the risk factors associated with an increased relapse. Overall (δT1T3), MASDO improved retrusion of the maxilla. We measured a significant advancement (6.1 mm) of the anterior maxillary segment in δT1T2 (A-McNamara classification) and increases in the overjet and the SNA, ANB, and nasolabial angles. However, skeletal relapse was evident in δT2T3, and the median percentage of relapse was 10%. To explore the risk factors, we subdivided patients with a δT1T2 of >5 mm into 2 groups based on the percentage of relapse (>15% vs ≤15%). There were significant differences between these groups in the vertical positions of the anterior nasal spine and point A, and the angle formed by the SN and palatal planes (SNPP), suggestive of intraoperative counterclockwise rotation of the maxilla. MASDO is effective for correcting midfacial deficiencies, but counterclockwise rotation of the maxilla during surgery may cause relapse.

Prevalence of Corneal Astigmatism and Anterior Segmental Biometry Characteristics Before Surgery in Chinese Congenital Cataract Patients.

The prevalence and the distribution characteristics of corneal astigmatism (CA) and anterior segment biometry before surgery in Chinese congenital cataract (CC) patients are not completely understood. This study involved 400 CC patients from the Zhongshan Ophthalmic Center enrolled from February 2011 to August 2015. Data on CA, keratometry, central corneal thickness (CCT) and anterior chamber depth (ACD) were measured by the Pentacam Scheimpflug System. The mean age of patients was 54.27 months, and the ratio of boys to girls was 1.53:1. The mean CA was 2.03 diopters (D), and 39.25% of subjects had CA values ≥2 D. The most frequent (71.8%) diagnosis was with-the-rule astigmatism. Oblique astigmatism was present in 16.2% of cases, and 12% of cases had against-the-rule astigmatism. The mean keratometry measurement of cataractous eyes in bilateral patients was significantly larger than that in unilateral patients. Girls had a larger mean keratometry but a thinner CCT than did boys. The CA, CCT, and ACD of cataractous eyes were significantly larger than those of non-cataractous eyes in unilateral patients. The CA, mean keratometry, CCT, and ACD in CC patients varied with age, gender, and laterality. Fully understanding these characteristics may help inform guidelines and treatment decisions in CC patients.

Dentate Transport Discs Can Be Used to Reconstruct Large Segmental Mandibular Defects

This study tested the use of a dentate transport segment for the reconstruction of a large U-shaped defect in the anterior segment of the canine mandible using a novel curved reconstruction plate. The quality and quantity of bone regenerate formed by dentate versus edentulous transport segments were compared. In 5 adult foxhound dogs, a defect of 70 to 75mm was created in the canine mandible by excising the mandible anterior to the right and left fourth premolars. Reconstruction was performed by trifocal distraction osteogenesis using a bone transport reconstruction plate (BTRP-02), with 2 transport units being activated simultaneously, one on either side of the defect, 1 dentate and 1 edentulous. Bilateral distraction proceeded at a rate of 1mm/day until the segments docked against each other in the midline. After 39 to 44 days of consolidation, the animals were euthanized. The quantity and quality of bone regeneration on the 2 sides were compared using micro-computed tomography. The defect reconstruction was successful. The amount and quality of bone formed by the transport segments were similar on the 2 sides. There were no major differences in the bone volume fraction and density of the regenerate bone formed by the 2 transport segments. The bone volume fraction and density of the regenerate bone were considerably lower than those of the host bone in the distal segments, likely owing to the short consolidation period. Bone transport remains a viable option in reconstructing anterior segmental defects in the mandible. The use of dentate or edentulous transport segments for reconstruction provides options for thesurgeon in often highly compromised patients requiring these surgeries.

Advancement of maxillary anterior segment by distraction osteogenesis for severe maxillary retrusion in cleft lip and palate

Background Maxillary anterior segmental distraction osteogenesis (MASDO) is a recently used method for correction of severe maxillary retrusion in cleft lip and palate (CLP) patients. In this article, we evaluated the feasibility of MASDO using rigid external distraction (RED) and rapid orthodontic tooth movement to correct severe maxillary retrusion in CLP patients. Methods Fourteen male and five female complete CLP patients between the ages of 18 and 22 years (mean age 19.7 years) at the time of distraction, with severe maxillary retrusion, were treated with the rigid external distraction (RED) device after maxillary anterior osteotomy. Rapid orthodontic tooth movement was started one week after the MASDO. Standard profile photographic, cephalometric films were obtained preoperatively and after therapy. Sella-nasion-point A (SNA) and Sella-nasion-point B (SNB) angles were measured to reflect changes in maxillary and mandibular position, and the distance between anterior nasal spine and posterior nasal spine (ANS-PNS) was measured to represent the maxillary dental arch length. Results The SNA angle increased from an average of 74.6° (range 73.0°-78.0°), preoperatively, to 83.4° (range 78.6°-88.0°) after the RED was removed (P <0.01). All cases of severe maxillary retrusion were improved. Nine patients' profiles became harmonious after therapy. One patient had a bimaxillary protrusion deformity and needed further surgery. The regenerate alveolar crest and edentulous space on both segments was almost completely eliminated after rapid orthodontic tooth movement. Conclusion MASDO with the RED system and rapid orthodontic tooth movement is a successful way of correcting severe maxillary retrusion in CLP patients.

Clinical Evaluation of Accuracy of Horizontal Meridian Limbal Marking

To assess the horizontal meridian misalignment of limbal marking under a slit lamp microscope by means of anterior segmental image assessment. A consecutive series of the 32 eyes of 16 subjects (7 males and 9 females) aged 29 ± 6 years (range, 23-44 years), who had refractive errors but were otherwise healthy, were used in this study. With each subject seated at the slit lamp and a coaxial slit turned to the horizontal meridian, we aligned the subject's head vertically and placed two reference marks aligned with the 3- and 9-o'clock positions on the limbal conjunctiva, using a marker pen or a toric marker. We quantitatively evaluated the accuracy of axis aliment by determining deviation from the horizontal reference line using a corneal topographer with an anterior segment image. The amount of the axis misalignment was 3.4° ± 2.2° (range, 0°-8°) when the marker pen was used, and 6.9° ± 5.0° (range, 0-24°) when the toric marker was used. Location identification using the toric marker showed a significantly larger deviation in axis alignment than that using the marker pen (Wilcoxon sign rank test, p < 0.001). Horizontal limbal marking using a slit lamp microscope showed the axis misalignment by an average of 3.4° to 6.9°. These alignment errors led to a reduction of the effectiveness of astigmatism correction by an average of 10% to 20%, which was not necessarily negligible when we aim to correct astigmatism completely, if possible. For successful astigmatic surgical procedures, increased accuracy of preoperative limbal marking by decreased misalignment of the astigmatism axis is essential.

上顎骨前方部延長術 －術式と要点－

Maxillary anterior segmental distraction osteogenesis (MASDO) is a rather new surgical orthodontic treatment to produce an ideal maxillary dental arch form in patients with cleft lip and palate. Different from total maxillary advancement by DO, this surgical procedure can solves the problems in the small and retruded maxilla without the risk of deterioration of velopharyngeal function, because the distracted segment is only made at the anterior part of the maxillary bone.To advance the anterior segment in only a single vector, a single palatal bone-borne distractor or toothborne distractor is effective, but two hybrid type distractors on each side of alveolar process can produce some rotational movements of anterior segment by controlling advancement amount in each side. Therefore, this procedure solves not only the size of maxillary arch but also the shape of deformed dental arch.As bone height and width at distracted space on alveolar process is enough for fuature alignments of crowding teeth or anterior movement of molars, this treatment is an effective pre-orthodontic surgical treatment for solving discrepancy of maxillary dental arch.

Anterior Segment Optical Coherence Tomography Analysis of Clinically Unilateral Pseudoexfoliation Syndrome: Evidence of Bilateral Involvement and Morphologic Factors Related to Asymmetry

To compare the morphology of the anterior chamber angle (ACA) and iris in eyes with pseudoexfoliation (PEX) syndrome to that of their clinically unaffected fellow eyes and normal control eyes. Forty-two patients with unilateral PEX syndrome and 42 normal subjects were studied. Eyes were separated into those with PEX, their clinically unaffected fellow eyes, and normal eyes. The dark-light changes of the ACA and iris were documented by anterior segment optical coherence tomography (AS-OCT) video recordings. The nasal ACA parameters including the angle opening distance at 500 μm (AOD500), the trabecular-iris space at 500 μm (TISA500), and the trabecular-iris angle at 500 μm (TIA500); anterior chamber depth (ACD); iris-lens contact distance (ILCD), and iris configuration were analyzed with the built-in software and a customized program. The ACA parameters were not significantly different among all three groups in the dark. The PEX eyes had significantly smaller ACA parameters than their fellow eyes and normal control eyes in the light. PEX eyes also had significantly shallower ACD, longer ILCD, and greater iris convexity (both in dark and light), and thinner iris (in dark) than their fellow eyes. The fellow eyes had significantly lower ACD both in the dark and light, and smaller angle opening distance at 500 μm and ILCD in the light than normal controls. There were no significant differences in the iris area among the three groups. Differences in the anterior segmental morphology are present between PEX and fellow eyes. These disparities may be related to the asymmetry in patients with the unilateral PEX syndrome.

Rotational movement of the anterior maxillary segment by hybrid distractor in patients with cleft lip and palate

Maxillary anterior segmental distraction osteogenesis (MASDO) is an effective surgical orthodontic treatment for the retruded maxilla in cleft lip and palate because of its benefit of the conservation of velopharyngeal function. Some reports showed MASDO using various devices, but they do not allow the rotational movement of the distracted anterior segment. In this article, we showed MASDO using hybrid distracters (DynaForm System: Stryker Osteosymthesis, Leibinger Micro Implants, Kalamazoo, MI), which allow the advance of the distracted segment with rotational movement. The hybrid distractor with 4 metal arms is secured beyond both alveolar osteotomy lines on each side. These 2 distractors permit rotational movement of the segment by controlling the amount of advancement on each side. For 6 patients with cleft lip and palate, MASDO using hybrid distractors was performed and the anterior segment moved at planned positions without any complications except lip discomfort, which disappeared after removal of the distractor. MASDO, using an institutionally diagnosed hybrid distractor can successfully achieve the necessary rotational movements of the anterior maxillary segment owing to its design, which incorporates some mechanical flexibility.

Anterior segmental distraction of the hypoplastic maxilla by a tooth borne device: a study on the movement of the segment

The aim of this study is to determine the relative movement of the teeth and bone after premaxillary distraction with a tooth-borne device constructed in the authors' centre. To evaluate the effects of this device on the anterior segment and teeth, the space formed between the anterior and posterior segments of the maxilla was measured on computerized tomography images from 10 patients. The average differences were 3.5mm at the apex level, 5.5 mm at alveolar ridge level and 7.4 mm at crown level on the right side. On the left side, the average differences were 3.2, 5.2 and 7.1 mm, respectively. There were statistically significant differences between all these measurements (p<0.05), but the difference between right and left sides was not statistically significant (p>0.05). The ratio between the movements at apex and crown levels was 46%. These results showed that the tooth-borne distractor was able to distract the anterior segment of the maxilla but it also caused anchorage loss of the maxillary incisors.

Severe bimaxillary protrusion with adult periodontitis treated by corticotomy and compression osteogenesis

This paper describes the case of a 50-year-old female with a Class II malocclusion who presented with severe bimaxillary protrusion and generalized alveolar bone loss due to adult periodontitis. The treatment plan consisted of extracting both upper and lower first premolars and periodontal treatment. Anterior segmental osteotomy (ASO) of the mandible and upper anterior segment retraction using compression osteogenesis after peri-segmental corticotomy (Speedy orthodontics) was performed. Correct overbite and overjet, facial balance, and improvement of lip protrusion were obtained. However, a slight root resorption tendency was observed on the lower anterior dentition. The active treatment period was 9 months and the results were stable for 27 months after debonding. This new type of treatment mechanics can be an effective alternative to orthognathic surgery. (Korean J Orthod 2009;39(1):54-65)