Experience with intraoral resection and immediate reconstruction in cases of radio-osteomyelitis of the mandible

Analytic Reviews : Hyperbaric Oxygen Therapy

The physiological effects of hyperbaric oxygen extend beyond the elevation of oxygen concentration in body tissues, and clinical data is available to support its use in more than gas bubble diseases. Hyperbaric medicine is discussed within the context of its recognized mecha nisms of action. The experimental data and clinical ex perience for hyperbaric oxygen therapy are reviewed for the following conditions: clostridial myonecrosis, necrotizing soft-tissue infections, chronic refractory os teomyelitis, radiation necrosis, refractory cutaneous ul cerations, compromised skin grafts and flaps, crush in jury and acute peripheral ischemia, carbon monoxide poisoning, arterial gas embolism, decompression sick ness, and thermal burns. Risks associated with hyper baric oxygen therapy are discussed, and cost analysis data are noted for specific conditions.

Osteoradionecrosis of Jaw in Head and Neck Cancer Patient Treated with Free Iliac Bone and Umbilical Fat Pad Graft

Osteoradionecrosis is one of the most serious complications of patients receiving radiation therapy. It is characterized by hypovascularity, hypocellularity, and hypoxia-inducing necrosis of bone and soft tissue following delayed healing. In this case, a 72-year-old man was referred to the Department of Oral and Maxillofacial Surgery complaining of trismus following extraction three months before first visit. He had a history of right tonsillectomy, radical neck dissection and radiotherapy performed due to right tonsillar cancer seven years prior. After the diagnosis of osteoradionecrosis on right mandibular body and angle, conservative antibiotic therapy was used first, but an orocutaneous fistula gradually formed, and extensive bony destruction and sequestrum were observed. Sequestrectomy, free particulated iliac bone and umbilical fat pad graft were performed via a submandibular approach under general anesthesia. Preoperative regular exams and delicate wound care led to secondary healing of the wound without vascularized free flap reconstruction.

Osteoradionecrosis of the mandible: treatment outcomes and factors influencing the progress of osteoradionecrosis

PURPOSE

The present study was undertaken to evaluate our recent experience with mandibular osteoradionecrosis (ORN) and to identify factors that contribute to its progress.

PATIENTS AND METHODS

The medical records of 114 patients who had been treated for ORN during a 16-year period (1989 to 2004) were reviewed. The patients were then divided into 2 groups according to their response to conservative treatment. Group 1 consisted of patients whose ORN resolved with conservative treatment (n = 47). Group 2 consisted of patients whose ORN was unresolved with conservative treatment or who had required radical resection of the involved tissue (n = 67). The information was obtained from the medical records of the patients and analyzed.

RESULTS

The patients whose ORN was associated with an early-stage tumor or preirradiation extraction had a favorable response to conservative treatment. However, those who had an advanced primary tumor, had continued smoking and drinking after radiotherapy, had received palliative radiotherapy or a radiation dose of more than 6,000 rads, and who had an orocutaneous fistula, a pathologic fracture, swelling, or trismus had a poor response to conservative treatment. In these latter cases, radical resection of the involved tissue proved useful.

CONCLUSIONS

The results of the present study have indicated that several factors (ie, the stage of the primary tumor, signs of ORN) can influence the progress of ORN. Our results suggest that radical resection is a useful method for treating mandibular ORN that does not respond to conservative treatment.

Scanning and transmission electron microscopy demonstrates bacteria in osteoradionecrosis

According to the current concept of osteoradionecrosis such tissue has become hypoxic, hypovascular and hypocellular and it has previously failed to show any bacterial growth. By using a molecular method, i.e., DNA-DNA hybridization, the presence of microorganisms in radionecrotic bone has formerly been demonstrated by us. The aim of the present study was to visualise bacteria in such bone by using scanning and transmission electron microscopy. Fourteen deep medullar specimens from resected radionecrotic mandibles were studied. Microorganisms were detected in 9 of the 14 samples (64%). The bacteria seen included rods, spirochetes and cocci, with rods being the predominant cells. One sample also contained yeasts (blastoconida and pseudohyphae). The data from this study strongly suggest an association between microorganisms and osteoradionecrosis. This may call for a revision of its presumed pathophysiology, including the possibility of an infectious etiology.

Management of advanced mandibular osteoradionecrosis with free flap reconstruction

BACKGROUND

The purpose of this study was to assess the effectiveness of free tissue transfer for treatment of advanced mandibular osteoradionecrosis (ORN) in head and neck cancer patients.

METHODS

We reviewed 29 patients who were treated for advanced mandibular ORN by radical resection and reconstruction with free flaps at our institution. All patients had either failed to respond to conservative treatment, including hyperbaric oxygen therapy and debridement or had pathological fracture due to ORN.

RESULTS

Twenty-four vascularized bone (17 fibula, five iliac, and two scapula), four rectus abdominis myocutaneous, and one radial forearm fasciocutaneous free flaps were used. The complications occurred in 6 of 29 patients (21%). A total of four flaps (14%) were lost. The mean follow-up was 2 years 9 months. All patients had complete resolution of ORN symptoms. No evidence of ORN recurrence was observed in any patient.

CONCLUSION

For advanced osteoradionecrosis of the mandible, radical resection followed by reconstruction using free flap provides a reliable means of obtaining good wound healing with acceptable aesthetic and functional results.

Treatment of mandibular osteoradionecrosis by cancellous bone grafting

PURPOSE

This study was undertaken to evaluate a new method in the treatment of mandibular osteoradionecrosis.

PATIENTS AND METHODS

Eight patients, seven male and one female, with a mean age of 64 years (range, 43 to 67 years), suffering from osteoradionecrosis of the mandible, two bilaterally and six unilaterally, were treated. Five initially had hyperbaric oxygen (HBO) followed by sequestrectomy, and three had sequestrectomy alone. Because healing failed to occur, all patients were treated by removal of the necrotic bone in the affected part of the mandible and filling the defect with compressed particulated cancellous bone and marrow from the tibia. The patients were observed for an average period of 39 months (range, 20 to 93 months).

RESULTS

Primary healing was achieved in two patients with unilateral osteoradionecrosis and HBO treatment. In another patient treated with HBO primary healing occurred on one side while the other healed secondarily. In the remaining five patients, complete secondary healing took place, but it was complicated in three patients by fistulas, two of which were associated with fractures of the mandibular body. The fistulas were excised, and complete healing of the soft tissues occurred, but the fractures resulted in pseudarthrosis.

CONCLUSIONS

The technique presented in this study can be useful in the treatment of osteoradionecrosis as an alternative to continuity resection and reconstruction with free osteocutaneous flaps, but, whenever possible, it should be proceeded by HBO treatment.

Pathological fractures of the mandible. A review of the etiology and treatment

A retrospective study was undertaken to analyse the etiology, site and treatment procedures of 30 pathological fractures of the mandible. Fifty percent of the fractures had an inflammatory cause. The remaining cases were associated with severe atrophy of edentulous mandibles (4), benign tumours (3), cysts (3), and primary or secondary malignancies (5). Regardless of the cause, the majority of the fractures occurred in the body of the mandible. Pathological fractures of the mandible most often have to be treated by eliminating the cause of the underlying condition while immobilizing the fragments either with osteosynthesis or archbars and intermaxillary fixation.

Osseointegrated implant rehabilitation of the previously irradiated mandible: results of a limited trial at 3 to 7 years

The use of osseointegrated dental implants in patients with defects of the head and neck acquired as a result of ablative surgery for malignancy is an accepted and valuable extension of the well-documented use of these implants for the treatment of edentulism. In patients who have received ionizing radiation as part of tumor therapy, the use of dental implants is poorly documented. A limited trial of 21 Brånemark implants placed in the previously irradiated mandibles of four patients is reported here. The implants have been in place and functioning for periods of 3 to 7 years. No implants have been lost. Patient selection, treatment, and complications encountered are discussed. Guidelines for further use of osseointegrated implants in patients with previously irradiated mandibles are suggested.

The conservative management of osteoradionecrosis of the mandible with ultrasound therapy

A regimen of ultrasound with local debridement and metronidazole has proved to be an effective and practicable treatment for osteoradionecrosis, achieving healing in 10/21 (48%) cases without the need for surgery or sophisticated technology. Nine further patients were successfully treated by covering the preserved mandible with a local intra-oral flap. Only 2 patients required mandibular resection with reconstruction. An ultrasound programme of 1 watt/cm2, 3 mega Hz. pulsed 1:4, 15 min a day for 60 days would seem to be optimum. However, a range of dosage needs to be further explored for inducing neovascularity and neocellularity in the irradiated tissues.

Osteoradionecrosis of the mandible: study of 104 cases treated by hemimandibulectomy

One hundred and four cases of osteoradionecrosis (ORN) of the mandible following irradiation of head and neck cancer are reported. Conservative management for ORN failed in all cases. Indications of hemimandibulectomy included intractable pain, severe trismus, pathological fracture, oro-cutaneous fistula and persistent exposure of bone. Surgical approach was intra-oral in 100 cases and extra-oral in four. Immediate soft tissue reconstructions were carried out in 20 per cent cases. Post-operative complications included minor sepsis (8.6 per cent), major sepsis (2.9 per cent), haemorrhage (2.9 per cent) and fistula (3.8 per cent). Major complications occurred only in patients treated exclusively by external irradiation at doses equal to or higher than 65 Gy. Relief from pain and trismus was obtained and normal swallowing was established following radical surgery.

The management of osteoradionecrosis of the jaws

Therapeutic measures used in the management of osteoradionecrosis (ORN) of the jaws are reviewed with reference to clinical case material. The development of rational treatment regimes designed to deal with the underlying pathological problem are discussed.

Osteoradionecrosis of the jaws

One hundred nine cases involving patients who had received radiation therapy for head and neck cancer were reviewed. Osteoradionecrosis of the mandible developed in only three patients in this group. Postirradiation extractions were not identified as a significant risk factor for such necrosis.

Actinomyces israelii in osteoradionecrosis of the jaws. Histopathologic and immunocytochemical study of five cases

Five surgically treated patients with osteoradionecrosis of the jaws are presented. The clinical history of the disease varied from 3 to 17 years. In three cases the progression of the disease was enhanced by surgical procedures performed in the irradiated area causing exfoliation of the premaxillary area in one case and spontaneous mandibular fracture in two cases. Actinomyces israelii was demonstrated in tissue sections of all five cases by using FITC-labeled specific antiserum and additionally with peroxidase-antiperoxidase method in one case. Candida was found in histologic sections of three cases. Radiation damage in the oral soft tissues and jawbones makes the atmosphere favorable for anaerobic microorganisms. The present results indicate that the role of A. israelii in the pathogenesis of osteoradionecrosis of the jaws has not been fully appreciated.

Osteoradionecrosis: a new concept of its pathophysiology

The classic sequence in the pathogenesis of osteoradionecrosis of the jaws has been accepted as radiation, trauma, and infection. This paper challenges this sequence and offers a new one more accurately describing the biochemical and cellular pathology. The clinical data are based on 26 consecutive cases of osteoradionecrosis from which 12 en bloc resection specimens were cultured and stained for microorganisms. Review of the histories and treatments, as well as the microbial assays, indicates that microorganisms play only a contaminant role in osteoradionecrosis and that trauma is only one mechanism of tissue breakdown leading to the condition. The sequence suggested by this study is as follows: (1) radiation, (2) hypoxic-hypocellular-hypovascular tissue, (3) tissue breakdown, and (4) chronic non-healing wound.

Mandibular reconstruction: bone graft techniques

Results of treatment in a series of 60 patients undergoing mandibular reconstruction by a variety of methods are reported. Delayed reconstruction was performed, using a titanium mesh tray with cancellous bone fragments and block bone grafts removed from the iliac crest, rib, and mandible in 34 patients, with an overall success rate of 91%. Immediate reconstruction was performed with a wire mesh prosthesis containing particulate bone and composite flaps in 26 patients, with an overall success rate of 46%. Oral contamination of the graft at the time of surgery appeared to be the factor limiting the success of immediate mandibular reconstruction. Block grafts of bone were extremely reliable in reconstituting the continuity of the mandible when inserted through an extraoral approach as a delayed repair. Mandibular reconstruction was successfully accomplished even following high-dose radiotherapy.

The use of hyperbaric oxygen therapy in bony reconstruction of the irradiated and tissue-deficient patient

Eighteen bony reconstructions of the mandible or maxilla using a newly defined and specific hyperbaric oxygen protocol are reported. Eleven of 12 grafts in irradiated tissue met six rigid criteria for a 91.6% rate of success. All six grafts into scarred and deficient tissue beds also met the same criteria, for an overall success rate of 94%. The rationale for emphasizing preoperative tissue preparation using hyperbaric oxygen is discussed, as are the mechanisms of action of hyperbaric oxygen on a biochemical, cellular, and tissue level. Neovascularity and neocellularity are demonstrated histologically by human biopsy specimens, and this is suggested as being the reason for the excellent results of reconstruction in irradiated and/or deficient tissue beds.