Condylar remodelling in a severe class II deep bite dento-skeletal malocclusion treated with an ortho-surgical approach: A five-year follow-up case report.

Condylar displacement and remodelling are phenomena closely related to orthognathic surgery and critically involved in occlusal and skeletal stability. The aim of the present case report is to describe over time condylar displacement and surface remodelling after bilateral split sagittal osteotomy (BSSO) in an adult patient with severe class II skeletal malocclusion treated with ortho-surgical approach. A male of 21years comes to our observation. The extraoral examination shows a symmetrical square-shaped face, a convex profile, an acute nasolabial angle and a deep labiomental fold. Intraoral examination reveals a class II division 2 with a 2mm deviation of the mandibular midline to the left and the presence of a scissor bite of the bicuspids between quadrants II and III. The Spee curve and overbite are extremely accentuated (OV 14.3mm) as the overjet (11.1mm). Axiographic reconstructions of CBCT show a normal shape and position of both condyles. The cephalometric analysis shows a reduced lower facial height, a normal upper jaw position, a mandibular underdevelopment masked by a very developed symphysis and an extremely low divergence (FMA 11.2°). BSSO for mandibular setback was performed in the 13th month of orthodontic therapy. Original CBCT data before surgery (T0), at the end of treatment (T1), 2years postoperatively (T2) and 5years postoperatively (T3) were collected and reconstructed for 3-dimensional (3D) qualitative analyse. At the end of the surgical-orthodontic treatment (26months), good function and good aesthetics were achieved. The qualitative and comparative analysis of the superimpositions and the cuts made on the CBCT at T0, T1, T2, T3 showed a physiological remodelling and adaptation of the condyles.

Orthodontic-Orthognathic Management of a patient with skeletal class II with bimaxillary protrusion, complicated by vertical maxillary excess: A multi-faceted case report of difficult treatment management issues.

This case reports the unsuccessful first treatment and the subsequent retreatment of a 35-year old Asian female with a skeletal class II with bimaxillary protrusion, complicated by a deep bite and vertical maxillary excess. This case report highlights the multiple facets of a challenging treatment plan and discusses the ramifications of treatment when treatment does not go as planned. The initial treatment plan consisted of a surgical approach with a maxillary Le Fort I surgery to correct the malocclusion as per the patient's requests without mandibular surgery due to the inherent risk of paraesthesia. The second treatment plan consisted of a bimaxillary surgery with genioplasty. The surgical treatment utilized virtual surgical planning (VSP). The orthodontic treatment was concluded with a corrected overjet and overbite achieving optimum function and balancing the facial profile aesthetically. This case report highlights the need for clear communication of the treatment plan and also the unpredictability of certain treatment outcomes especially when the literature does not provide for definitive conclusions. In addition, it sheds light on the challenge of unpredictable response of soft tissue after surgical treatment and the importance of patient expectations of outcomes. It is hoped that the paper provides a platform for future discussions of difficult malocclusions.

An unusual case of invasive cervical resorption after piezosurgery-assisted en masse retraction.

A 16-year-old patient sought orthodontic correction for profile improvement and labially inclined maxillary incisors. She had Class II malocclusion, protrusive maxillary and mandibular incisors, and increased overjet and overbite with an American Board of Orthodontics discrepancy index value of 25. She was treated with maxillary premolar extractions and miniscrew-supported en masse retraction assisted with piezoincisions. Extraction spaces (7.5 mm per side) were closed with maximum anchorage in 10 months. Total treatment time was 23 months. Twenty-seven months after debonding, a pink spot was noted at the buccocervial region of the left central incisor. Radiographic evaluation on cone-beam computed tomographic scans revealed a severe case of invasive cervical resorption on both central incisors, around which the piezosurgical cuts had been made. Treatment proceeded with a nonintervention approach and the affected teeth were reinforced with a lingual retainer.

The effect of disc repositioning and post-operative functional splint for the treatment of anterior disc displacement in juvenile patients with Class II malocclusion.

PURPOSE: To evaluate the effect of temporomandibular joint (TMJ) disc repositioning and post-operative functional splint for the treatment of anterior disc displacement (ADD) in juvenile patients with Class II malocclusion. MATERIALS AND METHODS: Juvenile patients (≤20 years) who had bilateral TMJ ADD with and Class II malocclusion treated by disc repositioning and functional splints were included in the study. Magnetic resonance imaging (MRI) and cephalometric radiographs before surgery (T0), immediately after surgery (T1) and more than 3 months after surgery (T3) were obtained in all patients. Cephalometric values including condylar height, overjet, SNA, SNB and pogonion position etc. were measured and compared before and after disc repositioning by statistical analysis. Fourteen patients (13 female, 1 male) were included in this study. Their average age was 16.7 years (range, 12-20 years). RESULTS: Seven patients with 14 joints had an MRI at least 6 months (6-24 months, mean 14.3) prior to disc repositioning. When compared to the MRI taken just prior to surgery, of those 14 joints, 9 condyles (64.3%) had evidence of bone resorption, 5 condyles (35.7%) had new bone formation mostly at the posterior part of the condyle (21.4%). These MRIs showed the condylar height was reduced 0.81 mm ± 0.61 (P = 0.013). Pre-operative cephalometric radiographs showed increased overjet (P = 0.039). The mean post-operative follow-up was 9.4 months (range, 4-13 months). Postoperative MRI showed the condylar height increased 1.74 ± 0.98 mm after disc repositioning (P < 0.001). Newly generated bone was observed on all condyles. 84.6% of the new bone was formed on the superior and posterior-anterior surfaces. Postoperative cephalometric radiographs showed the SNB angle increased 1.83 ± 1.56°(P < 0.001), pogonion position (pg'-G') moved anteriorly 2.18 ± 3.13 mm (P = 0.028) and incisor overjet decreased 3.55 ± 1.86 mm (P < 0.001), whereas significant changes were not found in SNA, Sn - G Vert, Y-Axis, U1 SN, IMPA (L1-MP) and U1-L1 (P > 0.05). CONCLUSION: Conservative treatment for ADD with Class II malocclusion in juvenile patients may cause condyle resorption and aggravate the dentofacial deformity. Disc repositioning combined with post-operative functional splints can effectively promote condylar growth and help correct the dentofacial deformity.

Implant Treatment after Sagittal Splitting Ramus Osteotomy and Alveolar Ridge Augmentation in Patient with Mandibular Prognathism and Multiple Missing Maxillary Teeth.

An abnormal maxillomandibular ridge relationship frequently hinders oral implant treatment in patients with jaw deformities. Here, we describe a patient who was experiencing difficulty using dentures due to multiple maxillary tooth loss and mandibular prognathism. Treatment comprising sagittal splitting ramus osteotomy and alveolar ridge augmentation using bone grafts harvested from the mandibular ramus followed by implant treatment yielded good outcomes. The patient was a 47-year-old woman presenting with an unstable upper partial denture. Although prior prosthetic treatment for mandibular prognathism had resulted in normal overbite, she had since lost an increasing number of teeth due to advanced periodontal disease, impairing support for the denture. She was referred to the Department of Oral Implantology at the Tokyo Dental College Chiba Hospital in October 2008. Subsequent treatment comprised implant treatment following maxillary alveolar ridge augmentation and sagittal splitting ramus osteotomy to correct the maxillary-mandibular relationship. In January 2010, sagittal splitting ramus osteotomy and alveolar bone augmentation using a bone graft from the mandibular ramus were performed under general anesthesia. In July and August 2010, a total of 7 implants were placed in the maxilla and implant superstructure preparation started after 3 months. Taking both the patient's wishes and ease of maintenance into account, retrievable superstructures made of Auro Galvano Crown were fitted in April 2011. The jaw-to-jaw alveolar ridge relationship was improved by sagittal splitting ramus osteotomy, rendering subsequent treatment, from implant placement to superstructure preparation, feasible by conventional methods. The use of surplus bone generated during sagittal splitting ramus osteotomy for bone augmentation avoided the need to harvest bone from another area.

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.

Long-term surgical-orthodontic management of hemimandibular hyperplasia.

BACKGROUND: Hemimandibular hyperplasia (HH), also known as hemimandibular hypertrophy, is characterised by excessive unilateral three-dimensional growth of the mandible after birth. Vertical unilateral elongation of the mandible becomes clinically evident as a rare form of vertical facial asymmetry. Aberrant growth of the facial skeleton affects the developing dentition and the dental compensatory mechanism is usually unable to maintain optimal occlusal relationships. The resulting malocclusion is effectively managed by combined surgical-orthodontic care to address the facial, skeletal and dental problems that confront clinicians. Orthodontists are advised to assess patients with HH during the post-treatment retention stage for continuing mandibular growth and assess the stability of treatment outcomes with long-term follow-up and records as required. AIM: To present a case of hemimandibular hyperplasia treated successfully by combined surgical-orthodontic care and evaluated for stability over a seven-year follow-up period. METHODS: Surgical-orthodontic management was accomplished in four stages: 1) pre-surgical orthodontic; 21 surgical; 3) post-surgical orthodontic; and 4) post-treatment orthodontic retention. Complete orthodontic records, including extra- and intra-oral photographs, study models, and cephalograms plus panoramic radiographs were taken at the pretreatment, post-treatment, and seven-year orthodontic retention time-points. RESULTS: Facial, skeletal and dental goals were achieved in the three planes of space and the long-term stability of the treatment results was shown during a post-treatment orthodontic retention period of seven years. CONCLUSION: Hemimandibular hyperplasia is a true growth anomaly which may be managed effectively. Clinicians may expect successful long-term correction and stability by utilising a comprehensive surgical-orthodontic treatment approach.

[Application of semi-buried curvilinear distraction devices in complex management of lower micrognathia in children].

The aim of the study was to apply an effective treatment protocol with low morbidity for children with syndromic and nonsyndromic micrognathia using curvilinear distractors, intraoral approach and early orthodontic treatment. We report 7 patients aged from 3 to 13 years with bilateral mandibular hypoplasia. These patients were characterized by severe malocclusion, esthetic facial deformation and respiratory disorders. In 3 patients mandibular hypoplasia was combined with anterior open bite. The intraoral surgical approach was used in all cases. Good functional and esthetic results were achieved during treatment. The less traumatic intraoral approach, curvilinear distractors, ultrasound callus formation control and early orthodontic treatment assure the good functional and esthetic results in severe cases facilitating the continuinty in complex rehabilitation of the growing child.

Impact of orthosurgical treatment phases on oral health-related quality of life.

INTRODUCTION: In this cross-sectional study, we investigated the impact of the orthosurgical treatment phases on the oral health-related and condition-specific quality of life (QoL) of patients with dentofacial deformities. METHODS: Two hundred fifty-four orthognathic patients were allocated into 4 groups according to treatment phase: initial (not yet treated), presurgical orthodontics, postsurgical orthodontics, and retention. Data were collected using the Oral Health Impact Profile to evaluate the oral health-related QoL, the Orthognathic QoL Questionnaire to analyze the condition-specific QoL, and the Index of Orthodontic Treatment Need to assess malocclusion severity and esthetic impairment. Specific malocclusion characteristics were also documented. RESULTS: A negative binomial regression analysis showed that the initial group had a more negative oral health-related QoL than did the postsurgical, presurgical, and retention groups (relative risks, 1, 0.79, 0.74 and 0.25, respectively). The initial group had a more negative condition-specific QoL than did the presurgical, postsurgical, and retention groups (relative risks, 1, 0.77, 0.38 and 0.15, respectively) regardless of age, income, or education; women reported greater negative impacts than men. Certain occlusal traits were related to higher Orthognathic QoL Questionnaire scores (P <0.01). CONCLUSIONS: Patients who completed their orthosurgical treatment had a significantly better oral health-related QoL and a more positive esthetic self-perception than did those undergoing treatment and those who were untreated. Crowding, crossbite, open bite, concave profile, edge-to-edge overjet, or Class III malocclusion negatively affected oral health-related QoL.

Progressive changes in patients with skeletal Class III malocclusion treated by 2-jaw surgery with minimal and conventional presurgical orthodontics: A comparative study.

INTRODUCTION: In this study, we aimed to compare treatment efficacy and postsurgical stability between minimal presurgical orthodontics and conventional presurgical orthodontics for patients with skeletal Class III malocclusion. METHODS: Forty patients received minimal presurgical orthodontics (n = 20) or conventional presurgical orthodontics (n = 20). Lateral cephalograms were obtained before treatment, before orthognathic surgery, and at 1 week, 3 months, 6 months, and 12 months after surgery. RESULTS: Changes of overjet and mandibular incisal angle before surgery were greater in the conventional presurgical orthodontics group than in the minimal presurgical orthodontics group. Postsurgical horizontal changes in Points A and B, overjet, and mandibular incisal angle showed significant differences among the time points. Most of the horizontal and vertical relapses in the maxilla and the mandible occurred within the first 6 months in both groups. CONCLUSIONS: Minimal presurgical orthodontics and conventional presurgical orthodontics showed similar extents and directions of skeletal changes in patients with Class III malocclusion. However, orthodontists and surgeons should preoperatively consider the postsurgical counterclockwise rotation of the mandible when using minimal presurgical orthodontics. Close and frequent observations are recommended in the early postsurgical stages.

Do changes in oral health-related quality-of-life, facial pain and temporomandibular disorders correlate after treatment of severe malocclusion?

INTRODUCTION: The aim was to evaluate the relationships of changes in facial pain, temporomandibular disorders (TMDs) and oral health-related quality-of-life (OHRQoL) in adults who underwent orthodontic or orthodontic/surgical treatment. METHODS: Sixty-four patients (46 women, 18 men, range 18-64 years) with severe malocclusion and functional problems were treated in Oulu University Hospital. Of these, 44 underwent orthodontic-surgical and 20 orthodontic treatment. Data were collected with questionnaires and clinical stomatognathic examinations before and on average 3 years after treatment. The OHRQoL was measured with OHIP-14 (The Oral Health Impact Profile), the intensity of facial pain with the Visual Analogue Scale (VAS) and the severity of TMD with the Helkimo's anamnestic (Ai) and clinical (Di) dysfunction indices. RESULTS: A significant improvement was found in facial pain, signs and symptoms of TMD and OHRQoL after the treatment (p < 0.05). The decrease in VAS was associated with improvement in OHIP-14 severity (r = 0.296, p = 0.019). The correlations between changes in OHIP-14 severity and Ai and Di were not statistically significant. CONCLUSION: Treatment of severe malocclusion seemed to improve OHRQoL via decreased facial pain. Decreased facial pain was associated especially with improved OHRQoL dimensions of physical pain, physical disability and social disability.

Oro-facial characteristics and the surgical correction of patients affected by beta-thalassaemia: a review of the literature and report of a case.

Despite the fact that recent medical advances have improved the quality of life and increased the life expectancy of patients suffering from thalassaemia, no standard strategy or clinical guidelines are available for the correction of the presenting craniofacial anomalies. The aim of the present study is to review the craniofacial features of affected patients, and to discuss the orthodontic and orthognathic surgical treatment options available to manage the associated and characteristic facial deformity.

Postsurgical volumetric airway changes in 2-jaw orthognathic surgery patients.

INTRODUCTION: Findings from early cephalometric studies on airway changes after 2-jaw orthognathic surgery have been challenged because the previous anteroposterior interpretation of airway changes can now be evaluated in 3 dimensions. The aims of this study were to use cone-beam computed tomography to quantify the nasopharynx, oropharynx, and total airway volume changes associated with skeletal movements of the maxilla and mandible in a sample of patients undergoing 2-jaw orthognathic surgery for correction of skeletal malocclusion. METHODS: Skeletal movements and airway volumes of 71 postpubertal patients (31 male, 40 female; mean age, 18.8 years) were measured. They were divided into 2 groups based on ANB angle, overjet, and occlusion (Class II: ANB, >2°; overjet, >1 mm; total, 35 subjects; and Class III: ANB, <1°; overjet, <1 mm; total, 36 subjects). Presurgical and postsurgical measurements were collected for horizontal, vertical, and transverse movements of the maxilla and the mandible, along with changes in the nasopharynx, oropharynx, and total airways. Associations between the directional movements of skeletal structures and the regional changes in airway volume were quantified. Changes in the most constricted area were also noted. RESULTS: Horizontal movements of D-point were significantly associated with increases in both total airway (403.6 ± 138.6 mm(3); P <0.01) and oropharynx (383.9 ± 127.9 mm(3); P <0.01) volumes. Vertical movements of the posterior nasal spine were significantly associated with decreases in total airway volume (-459.2 ± 219.9 mm(3); P = 0.04) and oropharynx volume (-639.7 ± 195.3 mm(3); P <0.01), increases in nasopharynx (187.2 ± 47.1 mm(3); P <0.01) volume, and decreases in the most constricted area (-10.63 ± 3.69 mm(2); P <0.01). In the Class III patients only, the vertical movement of D-point was significantly associated with decreases in both total airway (-724.0 ± 284.4 mm(3); P = 0.02) and oropharynx (-648.2 ± 270.4 mm(3); P = 0.02) volumes. A similar negative association was observed for the most constricted area for the vertical movement of D-point (-15.45 ± 4.91 mm(2); P <0.01). CONCLUSIONS: Optimal control of airway volume is through management of the mandible in the horizontal direction and the vertical movement of the posterior maxilla for all patients. The surgeon and the orthodontist should optimally plan these movements to control gains or losses in airway volume as a result of orthognathic surgery.

A more accurate soft-tissue prediction model for Class III 2-jaw surgeries.

INTRODUCTION: The use of bimaxillary surgeries to treat Class III malocclusions makes the results of the surgeries more complicated to estimate accurately. Therefore, our objective was to develop an accurate soft-tissue prediction model that can be universally applied to Class III surgical-orthodontic patients regardless of the type of surgical correction: maxillary or mandibular surgery with or without genioplasty. METHODS: The subjects of this study consisted of 204 mandibular setback patients who had undergone the combined surgical-orthodontic correction of severe skeletal Class III malocclusions. Among them, 133 patients had maxillary surgeries, and 81 patients received genioplasties. The prediction model included 226 independent and 64 dependent variables. Two prediction methods, the conventional ordinary least squares method and the partial least squares (PLS) method, were compared. When evaluating the prediction methods, the actual surgical outcome was the gold standard. After fitting the equations, test errors were calculated in absolute values and root mean square values through the leave-1-out cross-validation method. RESULTS: The validation result demonstrated that the multivariate PLS prediction model with 30 orthogonal components showed the best prediction quality among others. With the PLS method, the pattern of prediction errors between 1-jaw and 2-jaw surgeries did not show a significantly difference. CONCLUSIONS: The multivariate PLS prediction model based on about 30 latent variables might provide an improved algorithm in predicting surgical outcomes after 1-jaw and 2-jaw surgical corrections for Class III patients.

Factors related to stability following the surgical correction of skeletal open bite.

OBJECTIVES: If a skeletal anterior open bite malocclusion is treated by orthognathic surgery directed only at the mandible, the lower jaw is repositioned upward in a counter-clockwise rotation. However, this procedure has a high risk of relapse. In the present study, the key factors associated with post-surgical stability of corrected skeletal anterior open bite malocclusions were investigated. MATERIAL AND METHODS: Eighteen orthognathic patients were subjected to cephalometric analysis to assess the dental and skeletal changes following mandibular surgery for the correction of an anterior open bite. The patients were divided into two groups, determined by an increase or decrease in nasion-menton (N-Me) distance as a consequence of surgery. Changes in overbite, the displacements of molars and positional changes in Menton were evaluated immediately before and after surgery and after a minimum of one year post-operatively. RESULTS: The group with a decreased N-Me distance exhibited a significantly greater backward positioning of the mandible. The group with an increased N-Me distance experienced significantly greater dentoalveolar extrusion of the lower molars. CONCLUSIONS: A sufficient mandibular backward repositioning is an effective technique in the prevention of open bite relapse. In addition, it is important not to induce molar extrusion during post-surgical orthodontic treatment to preserve stability of the surgical open bite correction.

Relapse and stability after mandibular setback surgery one year postoperatively: a retrospective study.

PURPOSE: A retrospective evaluation was performed of dentoalveolar and skeletal stability 1 year after mandibular setback surgery using intraoral vertical subcondylar osteotomy (IVSO) combined with intermaxillary fixation. PATIENTS AND METHODS: Twenty-eight patients (16 men, 12 women) with skeletal Angle Class III malocclusions were included. Mean age at start of treatment was 23.9 years. All patients underwent combined surgical and orthodontic treatment. Dental casts and cephalometric measurements were performed for each patient before orthodontic treatment and at 8 weeks and 1 year after surgery. RESULTS: Treatment changes from 8 weeks to 1 year after surgery were small but significant for the angular relationship between the maxilla and the mandible in the sagittal plane (ANB) (mean difference, -0.5 mm; P = .021), Wits appraisal (mean difference, -0.7 mm; P = .044), the inclination of the mandible in relation to the nasion-sella line (ML-NSL) (mean difference, -0.8 mm; P = .010), and the inclination of the lower incisors in relation to the nasion-point B line (Li-NB) (mean difference, -0.6 mm; P < .001). These findings for cephalometric values indicated a small skeletal relapse in sagittal and vertical relations. No significant dentoalveolar relapse occurred according to the dental cast evaluations. CONCLUSION: The results clearly show that orthodontic treatment combined with IVSO provides a stable dental and skeletal result 1 year after treatment.

Guide surgery osteotomy system (GSOS) a new device for treatment in orthognathic surgery.

INTRODUCTION: This article proposes an innovative and revolutionary diagnostic and therapeutic protocol for performing dentoalveolar osteotomies in office under local anaesthesia with piezoelectric surgery using a surgical acrylic guide produced through software-based planning. METHODS: The method was applied in the correction of crossbites, changing in the curve of Spee, incisal decompensations and dental ankylosis. Performing a preoperative CT with a special splint, optical scanning of the models and the subsequent planning with software has enabled us to produce a model with rapid prototyping with the design of the osteotomy on which the surgical guide was shaped, the use of the guide associated with piezoelectric surgery, allowed to perform surgery under local anaesthesia, with minimal invasiveness and high accuracy. RESULTS: Dentoalveolar immediate movements, with preservation of the roots of teeth involved, allow for rapid treatment of malocclusions which would be long and often difficult if not impossible to treat with orthodontics only. Dentoalveolar osteotomies associated to osteodistraction concepts, allow the orthodontist to achieve with accuracy the objectives required by the treatment plan. CONCLUSIONS: GSOS is a new method, which, utilizing 3D optical scanning images of models, software and piezoelectric surgery, allows to perform dentoalveolar movements which may be dangerous to the roots or for the periodontal support, with orthodontics only. It dramatically reduces total surgical-orthodontic treatment time, with obvious great patient satisfaction.

Severe unilateral scissor bite and bimaxillary protrusion treated by horseshoe Le Fort I osteotomy combined with mid-alveolar osteotomy.

This report describes an orthognathic surgical case employing horseshoe Le Fort I osteotomy (HLFO) combined with mid-alveolar osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) for a patient with severe unilateral scissor bite and bimaxillary protrusion. A female patient (aged 26 years, 2 months) presented with a chief complaint of dysmasesis caused by scissor bite on the right side. The clinical examination revealed difficulty in lip closure and a convex profile. Overerupted right maxillary premolars and molars and lingual tipping of the right mandibular premolars and molars were indicated before treatment. After 3 months of presurgical orthodontic treatment, two-jaw surgery involving a combination of HLFO with mid-alveolar osteotomy and BSSRO was performed. A good interdigitation in the right side was established by superior-posterior-medial movement of the dento-alveolar segment of the maxilla. Next, both the maxilla and mandible were moved superiorly and posteriorly to correct the improper lip protrusion, thereby improving the patient's profile. Our results suggest that this new orthognathic surgery technique-achieved by combining HLFO with mid-alveolar osteotomy and BSSRO-is effective for adult patients exhibiting severe unilateral scissor bite and bimaxillary protrusion.

One-stage microvascular mandible reconstruction and alloplastic TMJ prosthesis.

Severely deformed or absent temporomandibular joints (TMJ) benefit from total alloplastic joint replacement and large mandibular defects from revascularized free tissue transfer for reconstruction. However no cases of their combined one-stage placement with outcomes can be found in the literature. We present two cases with different indications and reconstruction. The first patient required mandibular body and ascending ramus reconstruction after previous sarcoma resection. This was with a condyle-bearing reconstruction plate which resulted in significant dysfunction, leaving the patient unable to open her mouth. A one-stage vascularized iliac crest free flap and alloplastic TMJ prosthesis was used to reconstruct the mandible. Subsequently, metal removal, soft tissue augmentation by lipotransfer and dental implant placement were performed. At 63 months follow-up patient was pain-free, with mouth opening, protrusion and lateral excursion back to normal. The second patient required mandibular body, ascending ramus and joint reconstruction, performed by transoral vascularized fibula free flap with temporal vessel anastomosis. The traumatic deep bite and posterior facial height were corrected, additional submandibular scars avoided by transoral placement of the fibula transplant and a miniaturized TMJ prosthesis along with the vascularised free flap with 28 months follow-up. A miniaturized TMJ prosthesis may become placed transorally for reconstruction of the TMJ, together with a vascularized free flap for mandibular reconstruction and promises good long-term stability with normal function above all for protrusion and lateral excursion.

A better statistical method of predicting postsurgery soft tissue response in Class II patients.

OBJECTIVE: To propose a better statistical method of predicting postsurgery soft tissue response in Class II patients. MATERIALS AND METHODS: The subjects comprise 80 patients who had undergone surgical correction of severe Class II malocclusions. Using 228 predictor and 64 soft tissue response variables, we applied two multivariate methods of forming prediction equations, the conventional ordinary least squares (OLS) method and the partial least squares (PLS) method. After fitting the equation, the bias and a mean absolute prediction error were calculated. To evaluate the predictive performance of the prediction equations, a leave-one-out cross-validation method was used. RESULTS: The multivariate PLS method provided a significantly more accurate prediction than the conventional OLS method. CONCLUSION: The multivariate PLS method was more satisfactory than the OLS method in accurately predicting the soft tissue profile change after surgical correction of severe Class II malocclusions.