Segmental Mandibular Resection Research Articles

Primary treatment of mandibular ameloblastoma with segmental resection and free fibula reconstruction: Achieving satisfactory outcomes with low implant-prosthetic rehabilitation uptake

Ameloblastoma is a locally aggressive and disfiguring oral cavity tumour and surgical management is the mainstay of treatment. The ideal management of ameloblastoma should minimise recurrence, restore function and appearance and present minimal donor site morbidity. Conservative management is associated with minimal downtime but high recurrence rates. By contrast, segmental mandibulectomy with appropriate margins have much lower recurrence rates but presents the challenge of reconstruction. Osseointegrated (OI) implants and permanent dental prosthesis, while ideal, are not always available. We conducted a retrospective review on 30 consecutive patients at our centre with unicystic and multicystic ameloblastoma who were treated with segmental mandibular resection and free fibula flap reconstruction. Only three patients underwent OI implant insertion, with 40% of the patients not receiving any form of dental rehabilitation. We performed a functional and aesthetic outcome survey to determine patient satisfaction with this form of treatment. At an average follow-up of 5 years, there were no recurrences of tumour in our population. Of the 26 patients who responded to the survey, 96% of the patients reported that they were satisfied with their appearance, 88% reported an absolutely normal diet and 93% of the patients reported no problems with donor site function. Overall, we found that low uptake of dental rehabilitation did not adversely affect patient satisfaction and outcomes.

A two-year audit of non-vascularized iliac crest bone graft for mandibular reconstruction: technique, experience and challenges.

ObjectivesNon-vascularized iliac crest bone graft (NVIBG) is a known treatment option in mandibular reconstruction following jaw resection, but no documented review of patients treated with NVIBG exists for northern Nigeria. The experience and technique from a Nigerian tertiary hospital may serve as baseline data for comparison and improvement of practice for other institutions.Materials and MethodsA retrospective review of medical records and patient case files from January 2012 to December 2013 was undertaken. All case files and other medical records of patients who had reconstruction with NVIBG for benign or malignant lesions with immediate or delayed reconstruction were selected for review.ResultsTwenty patients had mandibular reconstruction with NVIBG during the study period. Two patients were excluded because of incomplete medical records. Eighteen patients' (male=14, female=4) records were reviewed. Their ages ranged from 13 to 62 years (mean 26.0±10.6 years). Indications for NVIBG included jaw tumors (n=16; 88.3%), jaw cyst (n=1; 5.6%) and gunshot injury (n=1; 5.6%). Jaw tumors seen were ameloblastoma (n=15; 83.3%) and osteosarcoma (n=1; 5.6%). Treatments done were mandibular resection with condylar resection (n=7; 38.9%), mandibular segmental resection (n=10; 55.6%) and subtotal mandibulectomy (n=1; 5.6%). Patients' postoperative reviews and radiographs revealed good facial profile and continued bone stability up to 1 year following NVIBG.ConclusionNVIBGs provide an acceptable alternative to vascularized bone grafts, genetically engineered bone, and distraction osteogenesis for mandibular reconstruction in resource-limited centers.

Autologous Ilium Grafts: Long‐Term Results on Immediate or Staged Functional Rehabilitation of Mandibular Segmental Defects Using Dental Implants after Tumor Resection

It is a challenge for clinicians to restore oral function in patients with segmental defects of the mandible because of tumor extirpation. Dental implant therapy following vascularized autologous ilium grafts is an effective method to restore oral function in patients with mandibular segmental defects. The aim of this retrospective study was to investigate the long-term clinical outcomes of ilium grafts combined with immediate or staged mandibular dental implant therapy to restore craniofacial defects resulting from tumor resection. Over a 5-year period (2000-2004), 32 patients who underwent mandibular segmental resection for tumors were treated with vascularized ilium grafts to augment bone volume. Seventeen patients received phase I therapy (immediate placement of implants), and 15 patients underwent phase II therapy (delayed placement of implants). A total of 110 dental implants were placed in these patients for mandibular restoration of the defective areas. Information regarding implant success and survival rates, marginal bone loss, soft tissue inflammation, complications of prosthesis, and patient satisfaction for the 8 to 12 years following oral reconstruction was obtained from patient records. Although there was mild evidence of bone graft resorption, the vascularized autogenous ilium bone grafts were successful in all patients. The cumulative patient survival and success rate of the implants were 96.4% and 91.8%, respectively. The mean peri-implant bone resorption ranged from 1.0 to 1.2 mm over the 8- to 12-year follow-up period. The annual mean number of complications/repairs was from 0.11 to 0.07 per patient during the 8- to 12-year follow-up. Over 80% of the patients were fully satisfied with their restoration of oral function. This study demonstrates that reconstruction of mandibular segmental defects because of resection of mandibular tumors using dental implants therapy combined with vascularized autogenous ilium grafts is an effective method to restore oral function.

The deep circumflex iliac artery perforator flap (DCIAP)—A reconstructive option for the large composite oro-mandibular cutaneous defect

The deep circumflex iliac artery (DCIA) flap is often used for mandibular reconstruction but it is bulky and causes additional donor-site morbidity because of the inclusion of an “obligatory internal oblique muscle”. Large composite segmental mandibular resections that consist of floor of mouth, subtotal tongue, and adjacent facial skin are a challenge in terms of reconstruction. They often require 2 free flaps or a free scapular flap and both have disadvantages. The deep circumflex iliac artery perforator (DCIAP) flap with a cutaneous component overcomes the disadvantages. We describe reconstructions with DCIAP flaps in 3 patients with large mandibular composite segmental defects. We report our experience of the flap and discuss some of the difficulties we encountered and the points we learned perioperatively.

OP111: Biomechanical evaluation of mandible segmental reconstructions using different methods of fixation

A reconstruction plate is conventionally used for internal fixation and load bearing across a segmental defect often created following a resection for malignancy. The aim of this study was to evaluate whether a uniform plate design is suitable for managing the more common types of segmental defects. This study may also promote a better understanding of the critical sites of a reconstructive structure and the ideal plate characteristics required to support bone regeneration whilst decreasing the likelihood of fixation failure. A detailed patient based edentulous mandible model was developed from CBCT/DVT scanning using standard reverse engineering techniques. A uniform reconstruction plate was modeled and utilized. The finite element analysis was used to compare the commonly used combinations of screw fixations (non-locking or locking and bicortical or monocortical). The most common symmetrical and asymmetrical segmental mandibular resections were analysed. The stress values within the plate, screws and implant/bone interface were recorded. The common practice of inserting a minimum of 3 screws either side of the resection was effective. In general the screws closest to the resection showed significantly higher stress levels (60–320 MPa). The inter-segmental movements with different plate strengths were studied as this can influence the potential for bone regeneration. The unilateral defect reconstruction allowed the smallest deformation while the symphyseal bone support was the highest quality. This study has identified the most effective position, number and type of screw anchorage points for a uniform plate reinforcement of the common segmental defects. Future works will focus on the overall load bearing capacity and movements of differing types of reconstruction plate and screws to optimize and redistribute the remaining effective strength of the plate to facilitate the design of novel bone regenerative scaffolds.

Intraoral Microvascular Anastomosis for Segmental Mandibular Reconstruction Following Removal of an Ameloblastoma

Cases of immediate bony microvascular reconstruction following segmental mandibulectomy in children are hard to find in the current literature. Moreover, microvascular segmental mandibular reconstruction that adopts an intraoral anastomosis technique has not been described so far. Therefore, the present clinical report aims at extending the armamentarium of bony microvascular reconstruction in pediatric cases of segmental mandibulectomy by highlighting an intraoral microvascular anastomosing technique.A 6-year-old boy, who suffered from an ameloblastoma of the mural type in the mandible, received a radical segmental mandibular resection because of the high recurrence rate of this tumor entity. Immediate reconstruction was carried out with a fibular double-barrel graft. Microvascular anastomoses were performed in an end-to-end fashion with the facial artery and vein as recipient vessels. The postoperative course was uneventful. There was no impairment of speech, deglutition, mastication, and facial nerve function. The facial appearance remained unobtrusive. On removal of the reconstruction plate 3 months after the reconstruction procedure, bleeding from the reconstructed mandibular segment indicated vascularization of the graft.It seems that segmental mandibulectomy and simultaneous microvascular bony reconstruction do not necessarily lead to impaired function as far as speech, deglutition, and mastication are concerned. Instead, the intraoral anastomosis technique allows waiving extraoral skin incisions and subsequent scarring, leaving the facial appearance unchanged and unobtrusive. Especially, the potential risk of stigmatization of the patient is avoided. Therefore, decision making in the choice of 1 or the other reconstruction option following segmental mandibulectomy should always consider the adoption of an intraoral anastomosing technique.

Mandibular Resection and Reconstruction in the Management of Extensive Ameloblastoma

To present our experience with the management of 31 extensive mandibular ameloblastomas treated with segmental mandibulectomy, reconstruction with free fibula or iliac crest flap, and rehabilitation with immediate or delayed endosteal dental implants. The study sample comprised 31 patients with histologically confirmed mandibular ameloblastomas. Primary ameloblastomas were treated in 23 patients, and recurrent ameloblastomas affected 8 patients. Mandibular defect sizes ranged from 3.5 to 12.5 cm (mean, 5.6 cm). A free fibula osseous or osteocutaneous flap was used 17 times for reconstruction; in the remaining 14, a free iliac crest osseous or osteomuscular flap was chosen. Dental implants were positioned in 25 patients; implant procedures were performed simultaneously with reconstruction in 21 cases. All flaps were transplanted successfully, and no major complication occurred postoperatively. Final histologic examinations showed 27 multicystic and 4 unicystic ameloblastomas. Free margins were achieved in all patients. The duration of follow-up was 18 to 120 months (mean, 53.6 months). No patient showed clinical or radiologic signs of recurrence. The dental implant success rate was 100%. Segmental mandibular resection followed by immediate defect reconstruction with bone-containing free flaps with immediate dental implant placement should be considered as the treatment of choice for extensive mandibular ameloblastomas.

下顎歯肉癌術後顎動脈に仮性動脈瘤を発症した1例

We describe a rare patient with mandibular gingival cancer in whom a pseudoaneurysm of the maxillary artery developed after segmental mandibular resection, including the region from the floor of the mouth to the pharynx, and neck dissection, followed by reconstruction using a metal plate and a rectus abdominis myocutaneous flap. A mass measuring 35×25×20 mm was detected at the inner side of the reconstruction plate on postoperative contrast-enhanced CT, and angiography was immediately performed to confirm that it was a pseudoaneurysm. The aneurysm was located in the maxillary artery and was treated by coil embolization. Pseudoaneurysms occurring in the head and neck region, which usually develop secondary to acute neck injury, are rare, and few cases of pseudoaneurysm involving the external carotid artery have been reported. However, the mortality rate associated with carotid artery aneurysms is estimated to be as high as 30％, and early imaging diagnosis and treatment are therefore important for preventing fatal complications.

Condylar disarticulation; Analysis of 20 cases from a Nigerian Tertiary Centre

Background:A disarticulation resection is a variant of mandibular segmental resection in which the condylar articulation is sacrificed. Indication varies from primary condylar lesions to jaw conditions involving the condyle.Aim:This retrospective analysis was carried out to highlight the pattern of disarticulation resections carried out in our centre over a five-year period.Materials and Methods:Cases of mandibular resection were identified from the operation book. The medical records of patients who had disarticulation resection were then retrieved and analyzed for demography, indications for disarticulations, methods of reconstruction and complications.Results:A total of 20 cases of disarticulation with complete records were obtained, this constituted 24.7% of total mandibular resections in the department. There were 9 males and 11 females with a male: female ratio of 1:1.2. The age ranged between 13 and 59 years with a mean of 30.4 years (std. 12.0). Sixteen patients received autogenous bone graft; two were stabilized using Steinman's pins and two with reconstruction plates. One bone graft and one reconstruction plate were removed because of infection and exteriorization respectively. Condyle was not replaced in any case. Outcomes were satisfactory but jaw deviation on opening was a common complaint in all cases.Conclusion:Condylar disarticulation accounts for a considerably high percentage of mandibular resection in our centre. Non vascularized immediate bone grafting without actual joint reconstruction was common. No disarticulation was carried out for traumatic reasons.

Quality of life of patients with segmental mandibular resection and immediate reconstruction with plates

Quality of life of patients with segmental mandibular resection and immediate reconstruction with plates

Computer‐guided rapid‐prototyped templates for segmental mandibular osteotomies: a preliminary report

Segmental mandibular resection represents a challenge to maxillofacial surgeons in terms of accurate contouring of reconstruction plates, restoration of mandibular symmetry and maintaining accurate condylar position in the glenoid fossae. We propose a CAD/CAM technique for fabricating patient-specific templates to symmetrically prebend reconstruction plates, guide osteotomies and reposition the condylar process in the proximal edentulous segment in its preoperative position. We operated on two patients using this new technique. The custom-made templates showed excellent passive fit on the respective mandibles and accurately guided the reciprocating saw blade along the resection margins. The template was also capable of maintaining the spatial relation of the resected mandibles and the patients experienced excellent repeatable occlusion. Superimposition of pre- and postoperative cone-beam CT scans showed restoration of mandibular symmetry and maximum deviation of 0.4-1.4 (mean of 0.9) mm from the preoperative condylar position. The achieved resection margins using the template showed a mean distance of 1.17 mm from the virtually planned ones. We present an innovative computer-guided template that allowed for accurate guidance of mandibular resection margins and condylar positioning. The technique needs to be applied in a larger cohort of patients to verify the results. Further modifications of the design and rigidity of the template might proof beneficial.

Quality of Life of Patients With Segmental Mandibular Resection and Immediate Reconstruction With Plates

The surgical management of some head-and-neck pathology affects a patient's form and fundamental function and, eventually, the quality of the individual's daily life. Restoring mandibular continuity after resection will improve form, function, and eventually, quality of life (QOL). The aim of this study was to evaluate the effect of our limited restoration with immediate plate reconstruction after segmental mandibular resection on the QOL of patients. A total of 13 patients were included in the study. They were treated for benign but aggressive mandibular pathology. Treatment included segmental mandibular resection with immediate plate reconstruction. A modified University of Washington QOL questionnaire was used to assess QOL. Data on clinico-dermographic variables were also collated. A total of 17 surgeries were undertaken, with 16 implants placed. Patients with smaller tumors seemed to have better QOL scores than those with larger tumors. The overall QOL scores for younger patients seemed better than those of older patients. Spontaneous regeneration of the mandible, occurring in our younger patients, was an added reason for this seemingly better QOL. Patients with segmental mandibulectomy and spontaneous mandibular regeneration tended to have a better QOL than those with no reconstruction and immediate plate reconstruction.

Von Recklinghausen 病に合併した下顎歯肉癌の1例

Neurofibromatosis （NF） type 1, known as von Recklinghausen’s disease, is an autosomal dominant inherited disorder caused by a mutation of a gene on the long arm of chromosome 17. Malignant tumors are often observed in patients with NF, whereas oral carcinoma concurrent with NF is very rare. This paper describes a case of squamous cell carcinoma of the lower gingiva adjacent to a neurofibroma in a patient with NF type 1. A 57-year-old man with NF type 1 was referred to our hospital. Intraoral examination revealed two masses: one was a firm nodule on the buccal shelf of the lower left posterior region covered by ulcerated mucosa, and the other was a soft to firm nodule adjacent to the other one in the left cheek region and was covered by normal mucosa. Excisional biopsy of the two nodules was done. Histological examination showed that the nodule in the buccal region was squamous cell carcinoma （T2N0M0）, and the other was a usual type of neurofibroma. The patient underwent chemotherapy and radiotherapy, followed by local resection of the carcinoma. Local recurrence developed 1 month later. Mandibular segmental resection including the region of neurofibroma, followed by neck dissection and reconstruction with a rectus abdominus free flap was done. The patient has not had tumor recurrnce or metastasis for 8 years after mandibular resection.

A comparison of simulated jaw dynamics in models of segmental mandibular resection versus resection with alloplastic reconstruction

Composite mandibular resection resulting in mandibular discontinuity can alter jaw motion, occlusal forces, and mastication, whether or not the jaw is reconstructed. The biomechanical events associated with these changes are difficult to assess clinically and, therefore, are not well documented or researched. The purpose of this study was to model movements of a mandible with a discontinuity defect, and to compare them to movements of a mandible with its continuity restored by alloplastic reconstruction. Computational models were created with a novel simulation platform. The variables designed into the models included gravity, external forces, and jaw muscle activity. Each jaw was observed at rest, when opened by external force or by muscle drive, and during the generation of unilateral occlusal force on the nonoperated side. Scarring was simulated with springlike forces. Outputs included individual muscle forces and torques, as well as mandibular incisor and condylar motions. Both models displayed plausible resting postures, and jaw opening with deviation toward the defect side when scarring was simulated. Opening caused by downward force on the incisors differed from that due to muscle activation. Jaw rotations during unilateral molar contact on the unaffected side were muscle specific and influenced by mandibular discontinuity. Plausible jaw movements after hemimandibulectomy and/or alloplastic reconstruction could be predicted by dynamic modeling. The effect of soft tissue forces on jaw posture and movements varied with the condylar support available. In both models, different opening trajectories were produced by external force on the jaw and by jaw muscle activation. Mandibular rotation during unilateral molar contact depended on which muscles were activated, and the availability of bilateral condylar support.

Can transcervical incision alone be used for mandibular segmental resection in SCC cases?

Can transcervical incision alone be used for mandibular segmental resection in SCC cases?

Feasibility of alloplastic mandibular reconstruction in patients following removal of oral squamous cell carcinoma

Microvascular bone grafts have evolved as the preferred technique for mandibular reconstruction in irradiated tumour patients. However immediate reconstruction by bridging plates remains an option for patients whose clinical condition is not favourable for microsurgical reconstruction. This retrospective study evaluates the performance of alloplastic mandibular reconstruction in patients following removal of oral squamous cell carcinoma. Three hundred and thirty-four patients with primary (biopsy proven) oral squamous cell carcinoma without distant metastasis (stages II-IV), who were all treated by segmental mandibular resection and reconstruction by means of a titanium bridging plate were included. Two hundred and seventy-two patients received preoperative treatment, consisting of concomitant radiochemotherapy (RCT) (n=228), chemotherapy (n=34) and radiotherapy (n=10). Median follow-up was 5.1 years (min 0.3, max 18.0). The median 2-year-disease-specific survival rate (DSS) was 81.6%. Five-year-DSS and 10-year-DSS was 71.8% and 62.0%, respectively. One hundred and thirty-six plates were removed due to infection with intra- and/or extraoral exposure, seven plates because of fracture. Preoperative RCT (p=0.027), mandibular defects including the symphysis (p=0.016) and heavy smoking at the time of diagnosis (p=0.042) were associated with infection-related failure of the reconstruction plates. Reconstruction of mandibular defects with titanium bridging plates seems crucial in heavy smoking tumour patients with preoperative RCT as well as in mandibular defects including the symphysis.

Preservation of inferior alveolar nerve during extensive segmental resection and its reconstruction with iliac bone for treatment of odontogenic myxoma

Background and Objectives: The odontogenic myxoma is a benign tumour of mesenchymal origin, locally invasive, recurrent with slow grow. While both jaws can be affected, this tumour is slightly more common in the mandible. If left untreated, it can result in complications with increased possibility of morphofunctional damage. The therapeutic modalities range from curettage to in block resection. The aim of this study is to describe a clinical case of an extensive mandibular segmental resection for treatment of myxoma, its immediate reconstruction with autogenous bone with the preservation of the inferior alveolar nerve.

Autologous freeze-treated bone for mandibular reconstruction after malignant tumor resection: a study of 72 patients

Objective The aim of the study was to assess the possibility of mandibular reconstruction with autologous freeze-treated bone after mandibular resection for malignant tumors. Patients The medical records of 72 consecutive patients surgically treated with segmental mandibular resection and reconstruction with autologous freeze-treated mandible were reviewed. Results All tumors were in stage T4a for deep infiltration of the mandible. Soft tissues were reconstructed with a direct mucosal closure (4 cases), with a pedicled pectoralis flap (17 cases), and with a forearm fasciocutaneous free flap without or with radial periosteum (18 and 33 cases). Four patients presented with a recurrence after previous surgery and radiotherapy, and 26 patients underwent postoperative radiotherapy. We resected the mental arch in 35 cases and the lateral mandible in 37 cases. Forty-one patients (56.9%) retained their autologous mandibular graft. In 31 cases, the bone graft was removed for mucosal dehiscence and bone infection. Lateral resections achieved a better success rate than anterior resections (75.7% vs 37.1%). The pedicled pectoralis flap achieved the worse success rate (35.3%) in comparison with forearm fasciocutaneous flap (66.7%). Postoperative radiotherapy decreased the success rate (40.0% vs 69.1%). Conclusions Mandibular reconstruction with autologous frozen bone is an interesting alternative to more sophisticated methods for patients with oral cancer involving the bone. It is time and cost sparing in comparison to fibula or iliac crest flaps. However, in spite of any intraoral reconstruction, the success rate is not stirring. In our opinion, this type of mandibular reconstruction must be reserved to patients with lateral tumors, with poor prognosis, or severe comorbidities not allowing more complex bone reconstruction.

O.528 When should lip be split for segmental mandibular resections?

O.528 When should lip be split for segmental mandibular resections?

Osteonecrosis of the jaw (ONJ) in cancer patients treated with Bisphosphonates: how the knowledge of a phenomenon can change its evolution

Osteonecrosis of the jaw (ONJ) is a severe complication of bisphosphonates treatment. Bisphosphonates reduce skeletal adverse events and give a clinical benefit to cancer patients. Therefore, it is necessary to identify appropriate procedures to reduce ONJ injures by using a successful monitoring program. In a retrospective study we analyzed the impact of a prevention program based on clinical oral cavity examination, dentists, and patients' education. The aim of the study was to evaluate if this approach might improve ONJ outcome in patients receiving pamidronate or zoledronate. We analyzed retrospectively two different groups of patients treated at our Institution: patients treated from October 2003 to June 2005 (group A) and patients treated from June 2005 to April 2007 (group B). In June 2005 the prevention program started for all our patients. One hundred and eighty-six cancer patients with bone involvement, treated with bisphosphonates, were considered. Sixteen of them developed ONJ: eight before and eight after June 2005. We observed a consistent difference in the evolution of the two groups. In the first group, four patients underwent a major surgery (one partial maxillectomy, complicated by septic shock and oronasal communication; two partial mandibulectomies; and one segmental mandibular resection), with an important impairment of their quality of life; while the eight new ONJ cases, diagnosed after June 2005, were successfully treated without aggressive dental interventions, and achieved a good control of symptoms. Bisphosphonates-related ONJ is a frequent adverse event (8.6%). The monitoring program proved very efficient to improve the clinical outcome of ONJ, avoiding an aggressive treatment and using a conservative approach and medical therapy.