Surgery-first in interdisciplinary class II cases.

OBJECTIVES: To present an interdisciplinary case treated with a surgery-first orthognathic approach, followed by orthodontic and prosthodontic treatment. CLINICAL CONSIDERATIONS: After an accurate pre-operative virtual planning, a young patient with skeletal class II, retrognathia, and an anterior open bite was treated with bimaxillary orthognathic surgery without pre-surgical orthodontic decompensation. Orthodontic treatment was carried out post-operatively. The treatment was completed with a prosthodontic phase to improve the final esthetic outcome of the smile. CONCLUSIONS: A surgery-first approach allowed to achieve esthetic and functional results in a reduced treatment duration that remained stable over the course of 1 year. The outcomes were consistent with prior research in terms of advantages brought by following an accurately planned surgery-first protocol. Nevertheless, longer-term follow-up was required to evaluate the treatment stability. CLINICAL SIGNIFICANCE: An accurately planned surgery-first approach significantly helped in shortening the duration of the treatment, while providing a stable, functional, and esthetic solution to the patient's problems.

Surgical vs nonsurgical treatments in patients with anterior open-bite have similar effects in occlusal function: A 2-year follow-up study.

INTRODUCTION: This study aimed to investigate changes in bite force (BF) and occlusal contact area after anterior open-bite (AOB) treatment and compare the changes in surgical vs nonsurgical treatment. METHODS: This retrospective study included patients with AOB compared with normal occlusion. AOB was corrected by either intrusion of the maxillary molars (intrusion group, n = 19) or orthognathic surgery (surgery group, n = 37). The control group (n = 35) had a normal overbite relationship. Records of lateral cephalograms, BF, and occlusal contact area taken before (T0), immediately after (T1), and 2 years after (T2) orthodontic treatment were compared within and among the 3 groups. RESULTS: The open-bite group, including intrusion and surgery groups, had a lower BF and less occlusal contact area than the control group at T0 and T1 (P <0.001). However, there were no significant differences among the 3 groups at T2 (P >0.05). The intrusion and surgery groups showed no significant differences throughout the observation period extending from T0 to T2 (P >0.05). Although BF and occlusal contact area decreased at T1 compared with T0, they increased during retention and showed higher values at T2 than at T0. CONCLUSIONS: Treatment of AOB improved BF and occlusal contact area 2 years posttreatment. Orthognathic surgery and molar intrusion using orthodontic miniscrews can improve occlusal function similarly. Orthodontists can select either method depending on malocclusion severity and patient demand.

Treatment acceptance in adult patients with anterior open bite: A National Dental Practice-Based Research Network study.

INTRODUCTION: Orthodontists have many techniques to treat anterior open bites and must involve patients in making treatment decisions. This study aimed to investigate orthodontic treatment plan acceptance by United States adults with anterior open bites and to identify associations between treatment acceptance and patient demographics and dentofacial characteristics. METHODS: A prospective, observational cohort study enrolled the patients of 91 orthodontic providers. A total of 345 adults were included in the sample. Provider personal and practice demographics were captured. Patient demographics, treatment goals, dentofacial characteristics, and reasons for not accepting the recommended plans were recorded. Adjusted regression models were used to identify associations between patient characteristics and the likelihood of accepting the most highly recommended plan. RESULTS: Approximately 78% of patients accepted the most highly recommended treatment plan. 60% of the patients who were recommended surgical plans accepted them. Patients with a history of orthodontics and a concave profile were more likely to accept the most highly recommended plan. Insurance coverage for orthognathic surgery was associated with a higher acceptance rate for surgery. Severe crowding was associated with a lower acceptance of surgery. The most common reasons for declining the recommended plan were not wanting jaw surgery and considering the treatment to be too invasive, risky, and/or costly. CONCLUSIONS: Patient acceptance is less common at higher levels of invasiveness of treatment. Prior orthodontic treatment, concave profile, and insurance coverage for surgery were associated with accepting treatment. Most patients accepted a surgical plan when it was the most recommended option.

Surgical-orthodontic with atypical extraction pattern as a treatment for an anterior open bite: A case report.

This case report described th e surgical- orthodontic interdisciplinar y t reatment of a patie nt with skeletal anterior open bite, class III skelet al pa ttern, steep mandibular plane, increa sed lower face heigh t, and thin mandibular sym physis. The or thodontic p reparation included an unusual extraction pattern (maxillary right first molar, maxillary left second premolar, and mandibular right central incisor), combined with two-jaw surger y comprised of maxillar y advancement and d ifferential impac tion, b ilateral malarplasty augme ntation and man dib ula r asymmetric bilateral sagittal split osteotomy setback. The follow-up of a rare complication of surgical hooks breakage during surgery is reported. Guided by 3- dimesional digital platforms, treatment planning and execution, resulted in a more ba lan ced a nd proportionate face with functional occlusion, and the case stability is shown i n a 32-m onth follow-up.

Treatment of Severe Open Bite Malocclusion with Four-Piece Segmental Horseshoe Le Fort I Osteotomy.

Appropriate operations in severe anterior open bite (AOB) cases are extremely complicated to perform because of the multiple surgical procedures involved, the difficulty of predicting posttreatment aesthetics, and the high relapse rate. We herein report a 16-year-old girl with skeletal Class II, severe AOB malocclusion, and crowding with short roots, and aesthetic and functional problems. Four-piece segmental Le Fort I osteotomy with horseshoe osteotomy was performed for maxillary intrusion, and bilateral sagittal split ramus osteotomy (SSRO) and genioplasty were performed for mandibular advancement. The malocclusion and skeletal deformity were significantly improved by the surgical orthodontic treatment. Functional and aesthetic occlusion with an improved facial profile was established, and no further root shortening was observed. Acceptable occlusion and dentition were maintained after a two-year retention period. This strategy of surgical orthodontic treatment with a complicated operative procedure might be effective for correcting certain severe AOB malocclusion cases.

Dentoskeletal features and growth pattern in Beckwith-Wiedemann spectrum: is surgical tongue reduction always necessary?

OBJECTIVES: The role of tongue reduction surgery (TRS) in preventing excessive mandibular growth and anterior open bite in children with Beckwith-Wiedemann Spectrum (BWSp) is still controversial. This cross-sectional study aimed at comparing craniofacial growth pattern in children affected by BWSp either treated or not treated with early TRS for severe macroglossia. Considering the invasive nature of such surgery, the present study could help in clarifying the need for TRS to reduce or prevent growth disturbances. MATERIALS AND METHODS: Orthopantomography and lateral skull x-ray images were taken either from surgically treated or non-surgically treated patients, aged 5 to 8 years, to compare dentoskeletal features and craniofacial growth by cephalometric analysis. Molecular testing results were collected from their medical records. RESULTS: Eighteen BWSp patients were consecutively recruited: 8 underwent TRS at 14.9 ± 2.2 months of age, while 10 did not. Anterior open bite and dental class III were more frequently observed in the surgically treated group, but none showed skeletal class III. No statistically significant differences were observed in growth pattern, but children treated with TRS showed a tendency towards both maxillary and mandibular prognathism with protruding lower lip. Growth pattern seemed to be not related to molecular subtypes. CONCLUSIONS: These preliminary data suggest that early TSR does not improve craniofacial growth pattern and dentoskeletal features in BWSp children. CLINICAL RELEVANCE: Reductive glossectomy may not be justified for preventing or avoiding oro-facial deformities in BWSp; therefore, early monitoring of maxillofacial development of each affected child has a great clinical significance.

Posttreatment stability of an anterior open-bite by molar intrusion compared with 2-jaw surgery - a retrospective study.

OBJECTIVES: This study aimed to compare post-treatment stability in patients with anterior open-bite (AOB) between those treated surgically (orthognathic 2-jaw surgery) and non-surgically (molar intrusion using orthodontic miniscrews). MATERIALS AND METHODS: All subjects had initial overbite (OB) < -1 mm and lateral cephalograms taken before treatment (T0), immediately after AOB correction (T1), after orthodontic treatment (T2), and at least 1 year after treatment (T3). The non-surgical group was enrolled retrospectively; then, the surgical group was matched by OB, sex, and age to the non-surgical group (n = 21 each). Changes in cephalometric measurements during treatment (T1-T0), finishing (T2-T1), and retention (T3-T2) periods were compared between two groups. RESULTS: OB increased by 4.5-5.1 mm during the treatment period with 3.3 mm upward movement of the maxillary first molar (U6) in both groups. Changes in OB were not significantly different between the groups: 0.5-0.9 mm increase during the finishing period but 1.0 mm decrease during the retention period (P > 0.05). U6 moved 0.5 mm downward in non-surgical group and 0.1 mm upward in the surgical group during the finishing period, and 1.0 mm and 0.4 mm downward in the non-surgical and surgical groups, respectively, during the retention period. CONCLUSIONS: Post-treatment stability of AOB was similar for surgical and non-surgical methods (76.8 - 78.7%), although U6 moved more downward in the non-surgical group than in the surgical group. CLINICAL RELEVANCE: AOB without severe skeletal deformity can be treated by either molar intrusion or orthognathic surgery with similar treatment outcome and stability.

Vertical stability of different orthognathic treatments for correcting skeletal anterior open bite: a systematic review and meta-analysis.

BACKGROUND: Several orthognathic procedures have been applied to correct skeletal anterior open bites (SAOB). Which method is most stable has been debated and no consensus has been reached and there is no conclusive evidence for clinicians to use. OBJECTIVE: To analyse whether maxillary, mandibular, or bimaxillary surgery provides a better stability. MATERIALS AND METHODS: A systematic search was conducted up to December 2020 using PubMed, EMBASE, Medline, Scopus, Web of Science, Cochrane CENTRAL, and Google Scholar. We made direct comparisons among the controlled trials and also made indirect comparisons via subgroup analysis on the aspects of occlusional, skeletal, and dento-alveolar stability to assess the overall stability of each method. RESULTS: Finally 16 cohort studies were identified. At the occlusional level, pooled change in overbite was 0.21 mm in maxillary surgery, 0.37 mm in bimaxillary surgery, and -0.32 mm in mandibular surgery. At the skeletal level, pooled sella-nasion-Point A angle (SNA) was -0.12 degrees in bimaxillary surgery, -0.37 degrees in maxillary surgery and -0.20 degrees in mandibular surgery. The sella-nasion to palatal plane angle (SNPP) relapsed to a statistically significant degree in all samples received single maxillary surgery. Relapse of the sella-nasion-Point B angle (SNB) was 0.47 degrees in mandibular setback, -1.8 degrees in mandibular advancement, and -0.48 degrees in maxillary surgery. The Sella-Nasion to mandibular plane angle (SNMP) relapsed more in procedures involving bilateral sagittal split osteotomy than in other procedures. As for dento-alveolar changes, intrusion of molars and extrusion of incisors took place in most patients. CONCLUSIONS: Bimaxillary surgery produced the most beneficial post-operative increase in overbite, maxillary surgery led to a lesser but still positive overbite change, and mandibular surgery correlated with some extent of relapse. Skeletally, bimaxillary surgery was more stable than maxillary surgery at both SNA and SNPP; SNB was more stable in mandibular setback than advancement; and SNMP was unstable in both mandibular and bimaxillary surgeries versus maxillary surgery with comparable surgical changes. Dento-alveolar compensation helped maintain a positive overbite. REGISTRATION NUMBER: CRD42020198088.

Substantial Improvements in Facial Morphology through Surgical-Orthodontic Treatment: A Case Report and Literature Review.

Background and Objectives: The long face type is associated with excessive vertical facial growth and most often with anterior open bite. In many cases of anterior open bite of high severity associated with bimaxillary dento-alveolar protrusion, lips are unable to form an adequate seal at rest. This leads to many issues, including facial dysmorphism. The aim of this study was to describe the case of a 15 year old girl who addressed the orthodontist in November 2015, having complaints related to the skeletal and dental open bite. Case Description: A 15.7 year old patient required a consultation with the orthodontic service for impaired dento-facial aesthetics at rest, smile and speech due to an exaggerated superior protrusion of the upper frontal teeth, labial incompetence with excessive gingival exposure at rest and smile associated with upper and lower anterior teeth crowding. The orthodontic diagnostic consisted of skeletal open bite with a hyperleptoprosop morphological facial type, high degree of hyperdivergence, bimaxillary dento-alveolar protrusion, 7 mm skeletal open-bite, 3 mm vertical inocclusion of the anterior teeth, skeletal class II relationships, bilateral half cusp class II molar and canine relationships, labial incompetence, highly increased interlabial gap, facial asymmetry, excessive gingival exposure of 7 mm at smiling and bimaxillary anterior crowding. Because the patient initially refused orthognathic surgery, prior to starting the orthodontic treatment, the patient was recommended to receive a bilateral extraction of the first upper premolars. Key objectives of pre-surgical orthodontic treatment were to achieve a retroclined position of the upper incisors under their normal inclination for the planned upward maxillary rotation, to maintain slightly lower incisor proclination. The orthognathic surgery consisted of Le Fort I impaction osteotomy with 8 mm anterior impactation, bilateral sagittal split osteotomy, and mandibular repositioning using occlusal splint. Conclusions: At the end of the orthodontic-surgical treatment, the patient presented significant improvement in dento-facial aesthetics, and optimal skeletal, muscular and dental balance.

Vertical segmental anterior mandibular distraction to aid closure of a severe anterior open bite associated with an accentuated reverse curve of Spee.

BACKGROUND: The correction of severe anterior open bite is technically challenging, often requiring the use of complex orthodontic mechanics and/or orthognathic surgery and has a relatively high risk of relapse. A marked reverse curve of Spee in the lower arch presents additional challenges when correcting a severe anterior open bite. METHODS AND MATERIALS: A 22.2-year-old Caucasian man presented with concerns relating to poor anterior occlusion associated with a 1.3-cm anterior open bite. There was an accentuated reverse curve of Spee to the lower arch, an increased maxillary-mandibular plane angle and increased lower face height. Multidisciplinary treatment involving the use of segmental anterior mandibular distraction to level the curve of Spee before undertaking a Le Fort I posterior maxillary impaction is described in this case report. RESULTS: Long-term post-treatment records showed stable anterior open bite correction. CONCLUSIONS: This case report illustrates the successful use of segmental anterior mandibular vertical distraction followed by conventional Le Fort I posterior impaction surgery to correct a severe anterior open bite associated with an accentuated reverse curve of Spee and high maxillary-mandibular plane angle.

Orthognathic surgery with two-segment le fort i and sagittal split ramus osteotomies of open bite deformity in an amelogenesis imperfecta patient via virtual planning: A case report.

Amelogenesis imperfecta (AI) is an enamel defect and is often associated with the anterior open bite (AOB) and transverse maxillary deficiency. It is known that in such cases when AI and AOB appeared together, posterior maxillary impaction with or without bilateral mandibular ramus osteotomies is a frequently preferred treatment option. Virtual planning is more reliable rather than the conventional model surgery planning, especially for complicated cases. Usage area of virtual 3D anatomical models reconstructed from Cone Beam Computed Tomography (CBCT) data is expanding day by day for both diagnosis and surgical planning. The aim of this study is to present a patient with AI and AOB and transverse maxillary deficiency and management of this case with virtually planned two-segment Le fort I and sagittal split ramus osteotomies followed by prosthetic rehabilitation.

Modified bonded acrylic expander in patient with anterior crossbite and pseudo-class III.

The open-bite treatment can be considered one of the most difficult malocclusions to treat in children as well as in adult patients. Several papers show that the traditional maxillary expander device contribute to increase the vertical face dimension and bite opening due to posterior rotation of the mandible, buccal tipping of lateral segments and cuspal interferences. Other more specific studies compared the effects of traditional maxillary expander to those of bonded acrylic expander and evidenced that the acrylic expander can better control the vertical effects of the maxillary expansion by the resin bite plane on which the heavy occlusal forces are exerted. We decided to use an acrylic expander in order to prevent worsening of anterior openbite after a careful assessment of nasal airflow by the otorhinolaryngologist.

Three-dimensional prediction of roots position through cone-beam computed tomography scans-digital model superimposition: A novel method.

OBJECTIVES: To introduce a new, fast, reliable, and free from software-related bias method to predict three-dimensionally the root position and angulation during and after orthodontic treatment. The final goal is to keep to a minimum the use of ionizing radiation by eliminating the necessity of multiple radiation exposure for checking root alignment. SETTING AND SAMPLE POPULATION: Pre- and post-treatment digital models and cone-beam computed tomographic (CBCT) scans from a patient were retrieved. MATERIAL AND METHODS: The post-treatment digital model (post-model) was set as the reference; pre- and post-treatment CBCT scans were pre-aligned to the post-model with a point set registration; iterative closest point algorithm was then employed for final adjustments. The accuracy of the proposed method was assessed by comparing the average distance between the expected root position setup with the true position of the roots, as from the post-treatment CBCT. RESULTS: After crown superimposition, 3D colour maps showed that the accuracy of the root prediction was below 0.1 mm. CONCLUSION: The proposed digital workflow allows to predict in an accurate and truly three-dimensional way the final position of roots, when an initial CBCT is available, without the need of an extra X-ray examination for the patient at the end of treatment. The limitation of the exposure to mid- and post-treatment X-rays is in accordance with the ALARA (As Low As Reasonably Achievable) principle and it is even more relevant in growing patients.

Condylar Resorption After Orthognathic Surgery.

The aim was to postoperatively evaluate a conservative treatment approach to bilateral condylar resorption after orthognathic surgery. A retrospective study was carried out on 730 consecutive patients undergoing sagittal split osteotomy, 2013 to 2016. The mean follow-up period was 2.29 years. Clinical and radiographic findings of patients with postoperative bilateral condylar resorption were searched. Syndromic patients and patients with juvenile rheumatoid arthritis were excluded from this study. Of the 730 patients, 6 (0.82%) required treatments because of bilateral postoperative condylar resorption but had no surgery at the temporomandibular joint (TMJ). Five patients with TMJ symptoms because of postoperative condylar resorption were managed with conservative treatment. About 2 of the 6 patients were successfully retreated with orthognathic surgery in the upper jaw to close the open bite. The TMJ symptoms can successfully be managed with conservative therapy, whereas skeletal relapse can be retreated with orthognathic surgery in the upper jaw, depending on the amount of overjet. Patient undergoing orthognathic surgery may develop bilateral condylar resorption though the frequency is <1%, most of these patients can be managed conservatively.

Anterior open bite correction with 2-jaw orthognathic surgery.

A 26-year-old man with an anterior open bite was treated with orthodontics combined with 2-jaw surgery. Total treatment time was 19 months. Both his occlusion and facial appearance were significantly improved by the surgical-orthodontic treatment.

A comprehensive treatment approach for idiopathic condylar resorption and anterior open bite with 3D virtual surgical planning and self-ligated customized lingual appliance.

INTRODUCTION: We report the successful treatment of a 38-year-old woman with bilateral idiopathic condylar resorption and anterior open bite. She had incompetent lips, a gummy smile, increased lower facial height, high mandibular plane angle, skeletal and dental Class II malocclusion with mild mandibular crowding, increased overjet, and mandibular midline deviation to the right. METHODS: The treatment plan included: (1) presurgical alignment and leveling of the teeth in both arches; (2) jaw motion tracking (JMT) to detect mandibular movement; (3) 3-piece maxillary osteotomies with mandibular reconstruction and bilateral coronoidectomies; and (4) postsurgical correction of the malocclusion. The orthodontic treatment was performed with the use of custom lingual braces and clear brackets and the orthognathic surgery was planned with the use of virtual surgical planning. RESULTS: The idiopathic condylar resorption and anterior open bite were treated, crowding was eliminated in the lower anterior segment, correction of skeletal and dental Class II malocclusion was obtained, mandibular plane angle was reduced, and facial profile improved. CONCLUSIONS: The results suggest that esthetic and functional results can be achieved with the cooperation of 2 specialties and with the use of state-of-the-art technology.

Comprehensive treatment approach for bilateral idiopathic condylar resorption and anterior open bite with customized lingual braces and total joint prostheses.

This case report describes the successful treatment of a 14-year-old girl with severe bilateral idiopathic condylar resorption and resultant mandibular retrusion, increased overjet, and anterior open bite. The nonextraction treatment plan included (1) aligning and leveling the teeth in both arches, (2) performing Le Fort I maxillary osteotomy, bilateral condylectomy, and mandibular joint replacement, and (3) postsurgical correction of the malocclusion. The orthodontic treatment was initiated with the use of custom lingual appliances followed by orthognathic surgery planned with virtual surgical planning. Patient-fitted and customized temporomandibular joint implants were designed and manufactured based on the patient's stereolithic bone anatomic model. Treatment was concluded with detailed orthodontic finishing. Optimum esthetic and functional results were achieved with the cooperation of 2 specialties and the use of state-of-the-art technology.

Therapeutic Protocol for Orthosurgical Management of Class III Malocclusion in Patients With Cleidocranial Dysostosis.

Cleidocranial dysostosis (CCD) is a congenital skeletal disorder with significant manifestations in facial and dental development. Patients are affected with CCD present maxillary deficiency, late dental eruption, and supernumerary teeth. Early and multidisciplinary approach is necessary to treat CCD patients, especially to manage dental eruption and Class III malocclusion with maxillary deficiency. Several orthodontic and surgical interventions are performed to enable traction and extraction of teeth. Yet the maxillary deficiency may be protracted followed by orthodontic dental compensation. On the other hand, it is important to note that CCD patients' treatment is closely related to the severity of transversal and sagittal deformities, as well as the discrepancies in the lower third of the face. In this context, patients with facial impairment highly affected by CCD may need ortho-surgical decompensation to reach more aesthetic outcomes. The present study reports a case of a 14-year-old young patient affected by CCD. Clinically, the patient presented Class III malocclusion, maxillary deficiency, short lower facial third, posterior crossbite, and anterior open bite leading to facial disharmony. The patient underwent treatment in 2 stages: the interceptive approach aimed to transversally expand the maxilla and promote its protraction; and the corrective phase combined with the orthognathic surgery treated the patients' main complains; the anterior open bite, unerupted teeth, and chin prominence. The treatment approach applied in the clinical report allowed the correction of the malocclusion and facial profile satisfying completely the patient's expectations.

Beckwith-Wiedemann Syndrome: Open bite evolution after tongue reduction.

BACKGROUND: Macroglossia causes functional deficits such as airway obstruction, drooling, phonation difficulties, and leads to protrusion of dentoalveolar structures resulting in an anterior open bite and a prognathic mandibular appearance. Macroglossia is present in the majority of patients with Beckwith-Wiedemann syndrome (BWS) and surgical treatment may be indicated. MATERIAL AND METHODS: A retrospective review was conducted including BWS patients who underwent surgical tongue reduction between 2000 and 2015 at the Hospital Universitario La Paz, Madrid. RESULTS: Out of 16 patients with BWS, surgery was performed in 11 cases. Tongue protrusion with open bite was the main indication for surgical treatment. Reduction glossectomy was performed using the keyhole technique. We analysed the relationship between age at surgery and evolution of open bite. Complications were minimal and satisfactory outcomes were observed with a decrease in anterior open bite. CONCLUSIONS: In this study we have observed that surgical treatment in patients with BWS and open bite accompanied by macroglossia seems to provide positive results with a satisfactory outcome in dentoskeletal alterations.

Cephalometric Improvement of Severe Microretrognathia With an Anterior Open Bite Using Curvilinear Mandibular Distraction Osteogenesis.

Curvilinear mandibular distraction osteogenesis (MDO) provides for multidimensional augmentation and rotation in mandibles with complex, abnormal morphology. This study aims to demonstrate cephalometric changes after curvilinear MDO.A prospectively maintained craniofacial database was queried for patients undergoing curvilinear MDO from 2009 to 2015. Demographic and operative data were collected. Cephalometric measurements were obtained from preoperative and postdistraction imaging, including sella-nasion-B point angle (SNB), mandibular plane angle (MPA), occlusal plane angle (OPA), and gonial angle (GA). Measurements were compared using a paired t test.Nine patients exhibiting microretrognathia and an anterior open-bite deformity had a mean age of 8.4 ±â€Š6.0 years and a mean follow-up of 23.2 ±â€Š25.3 months. Mean distance distracted was 32.6 ±â€Š7.2 mm, with augmentation in length and height, and rotatory closure of anterior open bites. Preoperative SNB versus postdistraction was 66.9 ±â€Š4.2 versus 78 ±â€Š9.1° (P = 0.0029). MPA, OPA, and GA all decreased (61.0 ±â€Š10.7 vs. 45.7 ±â€Š11.1°, P = 0.0066, 37.3 ±â€Š8.9 vs. 25.7 ±â€Š6.0°, P = 0.0025, 140.3 ±â€Š16.1 vs. 127.3 ±â€Š13.2°, P = 0.0019, MPA, OPA, and GA, respectively), trending toward normalization. Airway diameter increased by 7.1 ±â€Š2.8 mm. Anterior bite improved by 7.2 ±â€Š1.9 mm. Complications arose in 2 subjects including device malfunction and wound infection.Curvilinear MDO results in dramatic cephalometric improvement in patients with severe microretrognathia and anterior open-bite. The procedure is associated with a high rate of complications, and long-term stability of movement has yet to be documented.