Yuchun Hsu

Angiogenesis and osteogenesis enhanced by bFGF ex vivo gene therapy for bone tissue engineering in reconstruction of calvarial defects.

Reconstruction of bone defects by tissue engineered substitutes requires coordinated coupling between osteogenesis and angiogenesis. Basic fibroblast growth factor (bFGF or FGF-2) is a protein which acts actively in osteogenesis and angiogenesis during skeletal healing and development. It is hypothesized that BMSCs transfected with bFGF can directly stimulate regeneration of vascular tissue, and subsequently enhance osseous formation and remodeling after implantation of the tissue engineered bone. This study was designed to examine the impact of bFGF-BMSCs, seeded on nano-hydroxyapatite/polyamide66 (n-HA/PA66) composite scaffold, to enhance angiogenesis and osteogenesis in a calvarial critical-sized defect model in rats. To investigate the vascularization and bone formation of tissue engineered bone, the substrate was removed and processed for immunohistochemical, scanning electron microscopic examinations (SEM), reverse transcriptase-polymerase chain reaction (RT-PCR), dual energy X-ray absorptiometry (DEXA), microvessels counting, and new bone volume assay. The results demonstrate that bFGF mediated ex vivo gene transfer based on BMSCs can accelerate vascularization and bone regeneration on these composite scaffolds. The n-HA/PA66 scaffold combined with the bFGF-BMSCs may mimic the natural process of osteogenesis during repair of defect by tissue engineered bone.

Computer-Aided Design and Manufacturing and Rapid Prototyped Nanoscale Hydroxyapatite/Polyamide (n-HA/PA) Construction for Condylar Defect Caused by Mandibular Angle Ostectomy

The fracture or defect of the mandibular condyle is one of the serious complications during angle-reduction ostectomy. Reconstruction of such defects also is a daunting task. The case report describes a method based on computer-aided design/computer-aided manufacturing (CAD/CAM) and rapid prototyping nanoscale hydroxyapatite/polyamide (n-HA/PA) for individual design, fabrication, and implantation of a mandibular condyle. A 27-year-old woman with a square-shaped face who had previously undergone mandibular angle reduction reported with malocclusion, deviated mouth, collapse of the right side of the face, and masticatory problems. The reason for the problems was the unintended removal of the condyle during the ostectomy procedure. Using computed tomography (CT) data, a biomimetic n-HA/PA scaffold, and CAD/CAM for rapid prototyping by three-dimensional (3D) printing, a perfect-fitting condylar implant was fabricated. A surgical guide system also was developed to reproduce the procedures accurately so a perfect fit could be obtained during surgery. The patient ultimately regained reasonable jaw contour and appearance, as well as appreciable temporomandibular joint (TMJ) function.

CAD/CAM and rapid prototyped titanium for reconstruction of ramus defect and condylar fracture caused by mandibular reduction.

Fracture or defect of the mandible is a serious complication of mandibular angleplasty, and precise reconstruction for such defect is still a huge challenge. This case report provides a new method based on CAD/CAM and rapid prototyped titanium for individual design, fabrication, and implantation of a mandibular ramus and angle. A 25-year-old woman with a square-shaped face, who had undergone mandibular outer cortex split ostectomy (MOCSO) 3 months earlier, was afflicted by a series of symptoms: asymmetric face, collapse of the right face, masticatory problems, deviation during mouth opening, malocclusion, and TMJ clicks. These symptoms were caused by unintentional removal of the fractured ramus during MOCSO. By means of CT scan data, rapid prototyping, reverse engineering, 3D display, and CAD/CAM, the individualized titanium implant was designed and fabricated. The 3D demo system of operative scheme demonstrated the operative procedure, and determined the position of the implant so as to obtain a perfect fit. Postoperatively, the patient regained satisfactory morphologic symmetry, facial appearance, occlusion, and TMJ functions.

Autogenous coronoid process pedicled on temporal muscle grafts for reconstruction of the mandible condylar in patients with temporomandibular joint ankylosis

OBJECTIVE The aim of this study was to investigate the feasibility of autogenous coronoid process pedicled on temporal muscle grafts (ACPTMG) for reconstruction of the mandible condyle, and to compare the differences in clinical effects with autogenous free coronoid process grafts (AFCPG) in patients with temporomandibular joint (TMJ) ankylosis. STUDY DESIGN From 2003 to 2005, 48 patients who were diagnosed with uni- or bilateral TMJ ankylosis were randomly divided into 2 groups: group A(24 cases, 28 joints) and group B(24 cases, 30 joints). All patients underwent operations for resection of condyle and surrounding bony masses and simultaneous recreation of the glenoid fossa, which was followed with, for group A, condylar reconstruction using ACPTMG and, for group B, AFCPG, as well as interposition of temporal muscle myofascial flaps or native articular disc. The pre- and postoperative interinsicial opening values and mouth-opening deviation were measured, and decrease in height of mandible ramus was analyzed by panoramic radiographs. RESULTS All patients showed apparent improved joint function except 1 patient of group B, who showed signs of reankylosis of the joint (<20 mm mouth opening). Radiographic examination and 3-dimensional computerized tomography both showed the grafts to be well attached to the ramus in their original positions and adaptive remodeling in both groups, but relatively more evident bony resorption was noted in group B. The mean measurement of mouth-opening deviation and postoperative decrease in height of mandible ramus in group B were significantly higher than in group A. CONCLUSIONS Satisfactory clinical outcomes show that both ACPTMG and AFCPG seem to be alternative and promising methods in the treatment of TMJ bony ankylosis. Compared with AFCPG, the advantages of ACPTMG include less bony resorption and better long-term clinical outcomes.

Contouring of a square jaw on a short face by narrowing and sliding genioplasty combined with mandibular outer cortex ostectomy in orientals.

Background: A square face is considered unattractive in Orientals; thus, it has become a frequently encountered reason for patients undergoing face contouring surgery. While reviewing the unsatisfactory cases of mandibular reduction, the authors discovered that some failed cases were related to a square jaw on a short face. The conventional procedures fix only the posterior region of the mandible, resulting in increased prominence of the stunted or square chin and short face. Thus, the authors applied a narrowing and sliding genioplasty procedure combined with a mandibular outer cortex ostectomy technique to reshape a wide, weak chin, and a square jaw on a short lower facial contour into a slender and attractive oval face. Methods: From July of 2005 to October of 2009, there were a total of 57 patients in this study who underwent a narrowing and sliding genioplasty combined with a mandibular outer cortex ostectomy procedure to correct a square jaw on a short face. Results: The postoperative appearance of all 57 cases showed that the lower face had narrowed and had become softer, slender, and oval, with a slick mental region. Conclusion: Narrowing and sliding genioplasty combined with a mandibular outer cortex ostectomy procedure could efficiently adjust the shape and position of the chin to obtain a good proportion of the lower face and change a square, short face to a slender, oval one in a single operation in accordance with fashionable aesthetics in Orientals.

Correction of zygoma and zygomatic arch protrusion in East Asian individuals

OBJECTIVE Prominent zygoma is commonly seen in the East Asian population with the clinical characteristics of anteriorly and/or laterally projected zygoma and zygomatic arch resulting in an increased midfacial width. The esthetic surgical modification of zygoma is one of the major aspects of facial-contouring surgery in certain parts of the world. This article aims to evaluate the effectiveness of various surgical methods for reducing the prominent zygoma so as to obtain a harmonious and natural facial contour. METHODS Surgical approaches, such as zygomatic complex shaving, I-shaped osteotomy, L-shaped osteotomy, and C-shaped osteotomy were used according to the clinical characteristics of zygoma and zygomatic arch protrusion. The corrective effectiveness was then evaluated through cephalometric radiographs, 3D-CT, and pre- and postsurgical standard facial photographs. RESULTS The zygoma and zygomatic arch protrusion was effectively corrected resulting in improved facial contours in all cases postoperatively. The postoperative period was uneventful except for the slight limitation in mouth opening, which recovered fully after mouth-opening exercises. Serious complications, such as facial nerve injury, were not witnessed in our study. CONCLUSIONS Malar reduction is an effective and a safe method for the treatment of prominent zygoma. The selection of surgical procedure should be based on different presenting characteristics of zygoma and zygomatic arch protrusion. The correction of prominent zygoma should be designed well, performed precisely, and observed carefully to avoid severe complications so as to achieve a harmonious facial contour.

Sliding reconstruction of the condyle using posterior border of mandibular ramus in patients with temporomandibular joint ankylosis

The traditional approach for ankylosis is gap arthroplasty or interpositional arthroplasty followed by reconstruction of the condyle using, for example, costochondral grafts. As these are non-pedicled grafts, there is eventual resorption with subsequent decrease in height of the ramus, facial asymmetry and deviated mouth opening. The authors have applied the method of total and partial sliding vertical osteotomy on the posterior border of the mandibular ramus for reconstruction of the mandible condyle as a pedicled graft for the correction of temporomandibular joint (TMJ) ankylosis. From 2004 to 2008, 18 patients who were diagnosed with TMJ ankylosis underwent operations for resection of the ankylosed condyle. Two methods were performed depending on the level of osteotomy on the posterior part of the mandibular ramus. All patients were followed-up for an average of 36 months (range 24-48 months). All patients showed apparent improved joint function with no cases of re-ankylosis. The results showed that sliding vertical osteotomy on the posterior border of the mandibular ramus seems to be an alternative and promising method for condylar reconstruction in patients with TMJ bony ankylosis.

Total or partial inferior border ostectomy for mandibular contouring: indications and outcomes.

Among the East Asian population, a long or square face produces a characteristic coarse and masculine appearance and is therefore considered undesirable and unattractive. Because of this many Orientals seek to achieve a harmonious contour of their face by undergoing various cosmetic surgical procedures. Mandibular contouring for a long or asymmetrical face with/without square jaw is rarely reported in the literature and the objective of this study was to investigate the effectiveness of total or partial inferior border ostectomy for mandibular contouring and to discuss its indications. From July 2005 to November 2009, 74 patients in this study received mandibular contouring by total or partial inferior border ostectomy procedure to correct a disharmonious facial contour. Postoperatively the appearance of all 74 cases showed that the length of the lower 3rd of the face and the width of the mandible were decreased effectively, and the mandibular contour was improved. The final aesthetic outcomes were satisfactory for both the surgeons and the patients. The results suggest that facial contour could be improved by using total or partial inferior border ostectomy of the mandible thus achieving a harmonious facial outline based on East Asian aesthetics.

Comprehensive Consideration and Design for Treatment of Square Face

PURPOSE From an East Asian traditional esthetic viewpoint, a soft facial appearance seems to be more attractive. A prominent mandibular angle, a high zygomatic bone, and an inharmonious chin strongly lessen the attributes of femininity. Attention should be paid to the zygomatic projection and square mandible from the frontal view and the gonial angle and mental region configuration from the lateral view to obtain a slender oval face (melon seed face). PATIENTS AND METHODS From January 2005 through December 2010, 47 patients underwent a combination of 4 operative techniques to reshape a square face: L-shaped osteotomy, V-line osteotomy, mandibular outer cortex splitting ostectomy, and sliding genioplasty. RESULTS Outcomes in and feedback information from patients showed that these methods made the square face look more harmonious, with significant improvement of the middle and lower facial contours. CONCLUSIONS Asians with a square face have different combinations of facial features; thus, surgeries should be customized and designed comprehensively to achieve optimal results.

New horizontal v-shaped osteotomy for correction of protrusion of the zygoma and the zygomatic arch in East Asians: indication and results

Protrusion of the zygoma is commonly considered undesirable and unattractive among East-Asians, and many try to achieve a harmonious oval midface by having various cosmetic operations. However, effective contouring for a severe protruding zygoma has rarely been reported .The objectives of this study therefore were to investigate the feasibility and effectiveness of a horizontal V-shaped ostectomy for correction of protrusion of the zygoma and zygomatic arch, and to discuss its indications. From January 2008 to December 2011 we treated 27 patients by contouring of the zygoma with a horizontal V-shaped ostectomy through intraoral and preauricular incisions. The effectiveness was then evaluated with cephalometric radiographs, 3-dimensional computed tomography, and standard facial photographs taken before and after operation. The postoperative appearance of all 27 patients showed that the protrusion had been effectively reduced with no serious complications, and the facial contour had improved. The final aesthetic outcomes were satisfactory for both surgeons and patients. The horizontal V-shaped osteotomy is a good technique for the reduction of protrusion of the zygoma and zygomatic arch, and it has the advantages of more convenient multishifting, better results, and fewer complications. It also ensures the integrity of the structure of the malar complex.