Mandibular Repair Research Articles

A Comparison of In Vivo Bone Tissue Generation Using Calcium Phosphate Bone Substitutes in a Novel 3D Printed Four-Chamber Periosteal Bioreactor.

Autologous bone replacement remains the preferred treatment for segmental defects of the mandible; however, it cannot replicate complex facial geometry and causes donor site morbidity. Bone tissue engineering has the potential to overcome these limitations. Various commercially available calcium phosphate-based bone substitutes (Novabone®, BioOss®, and Zengro®) are commonly used in dentistry for small bone defects around teeth and implants. However, their role in ectopic bone formation, which can later be applied as vascularized graft in a bone defect, is yet to be explored. Here, we compare the above-mentioned bone substitutes with autologous bone with the aim of selecting one for future studies of segmental mandibular repair. Six female sheep, aged 7-8 years, were implanted with 40 mm long four-chambered polyether ether ketone (PEEK) bioreactors prepared using additive manufacturing followed by plasma immersion ion implantation (PIII) to improve hydrophilicity and bioactivity. Each bioreactor was wrapped with vascularized scapular periosteum and the chambers were filled with autologous bone graft, Novabone®, BioOss®, and Zengro®, respectively. The bioreactors were implanted within a subscapular muscle pocket for either 8 weeks (two sheep), 10 weeks (two sheep), or 12 weeks (two sheep), after which they were removed and assessed by microCT and routine histology. Moderate bone formation was observed in autologous bone grafts, while low bone formation was observed in the BioOss® and Zengro® chambers. No bone formation was observed in the Novabone® chambers. Although the BioOss® and Zengro® chambers contained relatively small amounts of bone, endochondral ossification and retained hydroxyapatite suggest their potential in new bone formation in an ectopic site if a consistent supply of progenitor cells and/or growth factors can be ensured over a longer duration.

Morphological Characteristics of Reparative Osteogenesis in Mandibular Repair with Different Osteoplastic Materials

Morphological Characteristics of Reparative Osteogenesis in Mandibular Repair with Different Osteoplastic Materials

PMS25 - Free-Flap Mandibular Reconstructions: Patient Demographics And Resource Utilization in the United States

Reconstructive surgery for mandibular defect often requires autologous tissue harvesting. This approach is successful in 95% of cases but is complex. Patient post-operative healthcare use and morbidity is not well characterized. This study was designed to better understand patient presentation and economic outcomes in the commercially-insured population. the Truven Commercial database was queried. All patients with inpatient admissions from 01-01-2007 to most current (up to 09-2017) with concurrent procedure codes for mandibular repair and bone flap/autograft harvesting were identified. All patients had at least 6 months continuous enrollment pre- and 30-days post index. Patient demographics and comorbidities (including Elixhauser Comorbidity Index (ECI)) at time of surgery were identified. All visits post-index were analyzed. Cost of care for the index and post-operative events were adjusted for inflation based on 2016 consumer price index. 1,426 patients were identified (average age: 26.5, 42.1% pediatric, 46.8% female), of which 273 (19.1%) had a diagnosis for mandibular or mouth-related cancer within the 6 months prior to surgery and 94 (6.6%) had an ECI of 3 or greater. Other frequent comorbidities included chronic pulmonary disease (5.5%) and hypertension (10.1%). Index surgery averaged US$ 41,935 (SD: US$42,337). At 12 months post-index, 16.4% had an all-cause inpatient readmission (6.5% including orthopedic or orthognathic procedures, 9.9% for non-orthopedic treatments), resulting in an average per-person cost of readmission of US$7,019 (SD: $26,581). In the outpatient setting, patients averaged 2.1 visits for orthopedic or post-operative care-related diagnoses or procedures in the 12 months post index, of which 1.6 was for physical therapy or prosthesis management and 0.17 for orthognathic care. Cost of post-operative outpatient care averaged US$1,542 (SD: 4,798) per patient. Total 12-months care thus averaged US$ 50,496 (SD: 73,716). Nearly one in six patients with mandibular reconstruction are readmitted for subsequent care in the 12 months post-index.

Multi-institutional Analysis of Surgical Management and Outcomes of Mandibular Fracture Repair in Adults

Mandibular fractures are rare, most commonly occurring in young male patients who present with facial trauma. The etiology, incidence, and presentation vary among previous publications depending on cultural and socioeconomic factors of the region of origin. This multi-institutional study aims to present demographic characteristics, surgical treatment, and clinical outcomes of surgical repair of mandible fractures in the United States. An analysis of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) adult databases of the years 2006 through 2014 was performed identifying 940 patients with an International Classification of Diseases, version 9 (ICD-9) diagnosis of either closed or open fracture of the mandible. Preoperative, perioperative, and postoperative details were categorized and evaluated for these two cohorts. Multivariate analysis was performed to detect risk factors related to any complications. Patients were predominantly male (85.7%), young with a mean age of 34.0 ± 14.8 years, and relatively healthy with body mass index of 23.6 ± 8.2 and an American Society of Anesthesiologists (ASA) class of 1 or 2 (84.4%). However, more than half were regular smokers (51.1%). The top five most frequent procedures performed for mandibular repair were exclusively open surgical approaches with internal, external, or interdental fixation in both cohorts. Patients with open fractures were more often admitted as emergencies, treated inpatient, required longer operative times, and presented with more contaminated wounds ( p < 0.05). Overall, medical (1.7%) and surgical complications (3.7%) were low. A high ASA class 3 or above and emergency operations were identified as risk factors for medical adverse events. Despite frequent concomitant injuries after trauma and a diverse array of mandibular injury types, our patient sample demonstrated favorable outcomes and low complication rates. Open surgical techniques were the most common procedures in this study representing the American population.

A clinical case of single-stage correction of penetration combined orofacial defect with two microsurgical autografts

After surgical treatment for locally advanced oral tumors with resection of soft tissues, mucosal membrane, and facial skeletal structures, there are penetration combined defects, removal of which is a challenge for reconstructive surgeons. Mandibular repair is one of the problems in the correction of combined oral defects. Surgeons use different grafts to remove mandibular defects. One-flap transplantation does not always solve all reconstruction problems and ensure the repair of the mucosal membrane, a soft-tissue component, skin integuments, and facial skeleton. The authors describe a clinical case of successful single-stage correction of penetration combined orofacial defect after resection of the tongue, mouth floor, en bloc resection of the lower jaw and mental soft tissues, bilateral cervical supramyochoroidal lymphadenectomy, stage LCL CM mandibular defect formation after J. Boyd, by using two microsurgical autografts (a peroneal skin-muscle-skin autograft and a radial skin-fascia one) in a 39-year-old female patient clinically diagnosed with carcinoma of the left mandibular alveolar ridge mucosa, Stage IVA (T4аN0M0). The Department of Microsurgery, P.A. Herzen Moscow Oncology Research Institute, Ministry of Health of Russia, has gained experience in comprehensively correcting extensive combined maxillofacial defects with two or more grafts in 27 patients who underwent autografting with a total of 73 flaps. The most functionally incapacitating and life-incompatible defect was removed at Stage 1 of reconstructive treatment. Delayed reconstruction was made after a complex of specialized antitumor therapy and assessment of treatment results in the absence of progressive growth. A great problem during multi-stage defect correction is presented by the lack of recipient vessels after cervical lymphadenectomy, the presence of soft tissue scar changes, trismus, temporomandibular joint ankylosis, contractures and displacement of the edges of the resected mandible, and autografting into the chronically infected area. Single-stage repair, including that using a few microsurgical autografts, is the operation of choice for adequate anatomic and functional rehabilitation, permits the promptest recovery of patients, reduces a postoperative period, and allows them to undergo an antitumor treatment cycle. However, the repair is possible, when the risk of disease progression is low, in specialized centers and when there are trained head and neck surgery and reconstructive microsurgery specialists and anesthesiologists.

Enhancement of osteogenesis and biodegradation control by brushite coating on Mg-Nd-Zn-Zr alloy for mandibular bone repair.

To diminish incongruity between bone regeneration and biodegradation of implant magnesium alloy applied for mandibular bone repair, a brushite coating was deposited on a matrix of a Mg-Nd-Zn-Zr (hereafter, denoted as JDBM) alloy to control the degradation rate of the implant and enhance osteogenesis of the mandible bone. Both in vitro and in vivo evaluations were carried out in the present work. Viability and adhesion assays of rabbit bone marrow mesenchyal stem cells (rBM-MSCs) were applied to determine the biocompatibility of a brushite-coated JDBM alloy. Osteogenic gene expression was characterized by quantitative real-time polymerase chain reaction (RT-PCR). Brushite-coated JDBM screws were implanted into mandible bones of rabbits for 1, 4, and 7 months, respectively, using 316L stainless steel screws as a control group. In vivo biodegradation rate was determined by synchrotron radiation X-ray microtomography, and osteogenesis was observed and evaluated using Van Gieson's picric acid-fuchsin. Both the naked JDBM and brushite-coated JDBM samples revealed adequate biosafety and biocompatibility as bone repair substitutes. In vitro results showed that brushite-coated JDBM considerably induced osteogenic differentiation of rBM-MSCs. And in vivo experiments indicated that brushite-coated JDBM screws presented advantages in osteoconductivity and osteogenesis of mandible bone of rabbits. Degradation rate was suppressed at a lower level at the initial stage of implantation when new bone tissue formed. Brushite, which can enhance oeteogenesis and partly control the degradation rate of an implant, is an appropriate coating for JDBM alloys used for mandibular repair. The Mg-Nd-Zn-Zr alloy with brushite coating possesses great potential for clinical applications for mandibular repair.

Adipose-derived stem cells and BMP-2 delivery in chitosan-based 3D constructs to enhance bone regeneration in a rat mandibular defect model.

Reconstructing segmental mandiblular defects remains a challenge in the clinic. Tissue engineering strategies provide an alternative option to resolve this problem. The objective of the present study was to determine the effects of adipose-derived stem cells (ASCs) and bone morphogenetic proteins-2 (BMP-2) in three-dimensional (3D) scaffolds on mandibular repair in a small animal model. Noggin expression levels in ASCs were downregulated by a lentiviral short hairpin RNA strategy to enhance ASC osteogenesis (ASCs(Nog-)). Chitosan (CH) and chondroitin sulfate (CS), natural polysaccharides, were fabricated into 3D porous scaffolds, which were further modified with apatite coatings for enhanced cellular responses and efficient delivery of BMP-2. The efficacy of 3D apatite-coated CH/CS scaffolds supplemented with ASCs(Nog-) and BMP-2 were evaluated in a rat critical-sized mandibular defect model. After 8 weeks postimplantation, the scaffolds treated with ASCs(Nog-) and BMP-2 significantly promoted rat mandibular regeneration as demonstrated by micro-computerized tomography, histology, and immunohistochemistry, compared with the groups treated with ASCs(Nog-) or BMP-2 alone. These results suggest that our combinatorial strategy of ASCs(Nog-)+BMP-2 in 3D apatite microenvironments can significantly promote mandibular regeneration, and these may provide a potential tissue engineering approach to repair large bony defects.

Antibiotic Selection for Open Reduction Internal Fixation of Mandible Fractures

Many mandible fractures are treated using open reduction internal fixation (ORIF) because of its superior stabilization of the fracture line, better healing, and faster recovery while minimizing the duration of immobilization of the mandible. However, ORIF requires an incision, which can lead to one of the most common complications of a mandibular fracture repair: postoperative wound infection. Historical controls have shown the infection rate after such surgeries to be anywhere from 6% to 32%. Most of the infections are due to normal oral flora, which is a mix of diverse facultative and obligate anaerobes. The current study was undertaken to determine whether a specific antibiotic regimen should be recommended to cover the normal flora. A retrospective review of 79 patients treated with ORIF mandibular repair was completed. The overall infection rate with use of antibiotic prophylaxis was 7.59%, but patients treated with clindamycin had an infection rate of 19.35%. The infection rate when using ampicillin/sulbactam was significantly lower than clindamycin. On the basis of this review, proper antibiotic prophylaxis should cover both potential aerobes and anaerobes.

Mandibular repair in rats with premineralized silk scaffolds and BMP-2-modified bMSCs

Premineralized silk fibroin protein scaffolds (mSS) were prepared to combine the osteoconductive properties of biological apatite with aqueous-derived silk scaffold (SS) as a composite scaffold for bone regeneration. The aim of present study was to evaluate the effect of premineralized silk scaffolds combined with bone morphogenetic protein-2 (BMP-2) modified bone marrow stromal cells (bMSCs) to repair mandibular bony defects in a rat model. bMSCs were expanded and transduced with adenovirus AdBMP-2, AdLacZ gene in vitro. These genetically modified bMSCs were then combined with premineralized silk scaffolds to form tissue-engineered bone. Mandibular repairs with AdBMP-2 transduced bMSCs/mSS constructs were compared with those treated with AdLacZ-transduced bMSCs/mSS constructs, native (nontransduced) bMSCs/mSS constructs and mSS alone. Eight weeks after post-operation, the mandibles were explanted and evaluated by radiographic observation, micro-CT, histological analysis and immunohistochemistry. The presence of BMP-2 gene enhanced tissue-engineered bone in terms of the most new bone formed and the highest local bone mineral densities (BMD) found. These results demonstrated that premineralized silk scaffold could serve as a potential substrate for bMSCs to construct tissue-engineered bone for mandibular bony defects. BMP-2 gene therapy and tissue engineering techniques could be used in mandibular repair and bone regeneration.

Reconstruction of the Mandibular Ramus/Condyle Unit Following Resection of Benign and Aggressive Lesions of the Mandible

The reconstruction of mandibular continuity defects using autogenous bone has a varied history. Segmental defects of a centimeter or less, if adequately immobilized, may well regenerate spontaneously without the need for a bone graft, particularly in younger patients. 1 Prein J. Treatment of Infected Fractures and Pseudarthrosis of the Mandible. in: Springer-Verlag, New York, NY1976: 169 Google Scholar , 2 Leopard P. Complications. Churchill Livingstone, New York, NY1985: 730 Google Scholar The immediate (or even delayed) nonvascularized intraoral grafting of larger segmental defects of the mandible has generally met with unacceptably high failure rates. 3 Millard D.R. Campbell R.C. Stokley P. et al. Interim report on immediate mandibular repair. Am J Surg. 1969; 118: 726 Abstract Full Text PDF PubMed Scopus (18) Google Scholar , 4 Ardary W.C. Reconstruction of mandibular discontinuity defects using autogenous grafting and a mandibular reconstruction plate: A prospective evaluation of nine consecutive cases. J Oral Maxillofac Surg. 1993; 51: 125 Abstract Full Text PDF PubMed Scopus (16) Google Scholar , 5 Schuller D.E. Bardach J. Monteith C.G. et al. Titanium tray mandibular reconstruction. Arch Otolaryngol. 1982; 108: 174 Crossref Scopus (17) Google Scholar , 6 Kudo K. Fujioka Y. Review of bone grafting for reconstruction of discontinuity defects of the mandible. J Oral Surg. 1978; 36: 791 PubMed Google Scholar , 7 Tidstrom K.D. Keller E.E. Reconstruction of mandibular discontinuity with autogenous iliac bone graft: Report of 34 consecutive patients. J Oral Maxillofac Surg. 1990; 48: 336 Abstract Full Text PDF PubMed Scopus (50) Google Scholar , 8 Lawson W. Biller H.F. Mandibular reconstruction: bone graft techniques. Otolaryngol Head Neck Surg. 1982; 90: 589 PubMed Google Scholar , 9 Lawson W. Loscalzo L.J. Baek S.M. et al. Experience with immediate and delayed mandibular reconstruction. Laryngoscope. 1982; 92: 5 Crossref PubMed Scopus (106) Google Scholar , 10 Adamo A.K. Szal R.L. Timing, results, and complications of mandibular reconstructive surgery: Report of 32 cases. J Oral Surg. 1979; 37: 755 PubMed Google Scholar This is probably because of a combination of salivary contamination of the graft, which decreases the number of viable cells, and the difficulty of obtaining a watertight intraoral closure, which leads to the possibility of wound breakdown. 11 Conley J.J. A technique of immediate bone grafting in the treatment of benign and malignant tumors of the mandible and a review of seventeen consecutive cases. Cancer. 1953; 6: 568 Crossref PubMed Scopus (26) Google Scholar There are, however, a small number of reports of successful large intraoral mandibular bone grafts carried out at the time of resection. 11 Conley J.J. A technique of immediate bone grafting in the treatment of benign and malignant tumors of the mandible and a review of seventeen consecutive cases. Cancer. 1953; 6: 568 Crossref PubMed Scopus (26) Google Scholar , 12 Manchester W.M. Immediate reconstruction of the mandible and temporomandibular joint. Br J Plast Surg. 1965; 18: 291 Abstract Full Text PDF PubMed Scopus (43) Google Scholar , 13 Obwegeser H.L. Simultaneous resection and reconstruction of parts of the mandible via the intraoral route in patients with and without gross infections. Oral Surg Oral Med Oral Pathol. 1966; 21: 693 Abstract Full Text PDF Scopus (46) Google Scholar , 14 Obwegeser H.L. Primary repair of the mandible by the intraoral route after partial resection in cases with and without pre-operative infection. Br J Plast Surg. 1968; 21: 282 Abstract Full Text PDF Scopus (10) Google Scholar

Mandibular Nerve Repositioning and Repair

Mandibular Nerve Repositioning and Repair

Mandibular Nerve Repositioning and Repair

Mandibular Nerve Repositioning and Repair

Early Definitive Bone and Soft-Tissue Reconstruction of Major Gunshot Wounds of the Face

The use of craniofacial surgical techniques, extended open reduction, rigid fixation with plates and screws, and the replacement of severely damaged or missing bone with immediate bone grafting in the treatment of complex facial fractures has been applied to the management of severe gunshot wounds of the face. Early definitive bone and soft-tissue reconstruction has been performed in 37 patients. One-hundred and seventy-seven primary bone grafts were utilized in 33 patients for orbital, nasal, zygomatic, and maxillary reconstruction. Twenty-six patients required mandibular repair with compression or reconstruction plates. Soft-tissue reconstruction was provided by a combination of flaps. Four patients had extensive soft-tissue loss replaced by free vascularized omental flaps. The omentum provided circumferential coverage of the mandibular reconstruction and reconstruction of the floor of the mouth and was then tunneled in a circle through both cheeks into the middle and upper face. The omentum reconstructed deficits in the hard palate and upper buccal sulcus and was then wrapped around all zygomatic, orbital, and midfacial bone grafts and used to fill in dead space in the maxillary, ethmoid, and frontal sinuses. The omentum is not used to provide contour and bulk, but to cover bone grafts and plates and fill in dead space. Carefully shaped bone grafts provide the correct craniofacial scaffold. Early restoration of a midfacial bony scaffold and the prevention of soft-tissue contraction facilitate secondary reconstruction. Four late total nasal reconstructions with tissue-expanded forehead skin wrapped around bone grafts were performed.

工作機械によるきょう部全層欠損 Ｄ‐Ｐ皮弁，前頭島状皮弁による再建の１例

Nowadays, facial trauma is getting much more complicated and severed along with the social factors.Progress in surgical, anesthetical and medical ambulatory care has made it possible to save severely injured patients. Such life-threatening forces also cause severe facial trauma and cases needing more complex treatment plans arc increasing.In this paper, a case of a 44 year old male treated with multiple reconstructive procedures is presented.The patient was caught in to an iron-work machine by his left forearm and had an abulsed right malar area. After first aid for life was given, he was transfered to our department. The extent of injury was confirmed to be a rt. cheek full-thichness defect, partial loss and fractures of maxilla and mandible, multiple facial lacerations and burns through the first operation included wound debridement and primary maxillary and mandiblar reduction and fixation.One month later, the facial defect settled to 6 × 9 cm and segmental loss of rt. mandible was evident. D-P flap and forehead island flap reconstruction for cheek defect, mandibular repair with Vitallium® cast splint and iliac bone graft, transposition of parotid duct to oropharynx were performed.Through 4 separate operations over 20 hours, good functional and cosmetic reconstruction was aquired.

Interim report on immediate mandibular repair

Immediate reconstruction of the resected mandibular arch using the total forehead as a lining flap and a bent rib on a Kirschner wire as the bone graft has been used for six years in thirty-one cases. Due to a 30 per cent failure in survival of the immediate bone graft, delayed immediate reconstruction is now favored. At the time of ablation the forehead flap replaces the lining but a K wire maintains position of the mandibular fragments. Six weeks later when the forehead pedicle is divided and the temporal portion replaced, the wire is removed and the bent rib graft on a K wire inserted. This has been responsible for an increase in the survival rate of the bone grafts.

Experimental mandibular repair with bone chips and no fixation.

Experimental mandibular repair with bone chips and no fixation.

A new approach to immediate mandibular repair

A new approach to immediate mandibular repair

A new approach to immediate mandibular repair

A new approach to immediate mandibular repair

A NEW APPROACH TO IMMEDIATE MANDIBULAR REPAIR.

A NEW APPROACH TO IMMEDIATE MANDIBULAR REPAIR.