Resection Of Mandible Research Articles

A new approach: Cervical approach for marginal resection of the posterior mandible

Gingival squamous cell carcinoma (SCC) of the posterior mandible often requires marginal resection of the mandible in conventional surgery. However, the posterior location of the lesion can limit surgical visibility, which is critical for complete tumor removal and minimizing recurrence. Typically, marginal resection of the posterior mandible is achieved through a midline lower lip incision and mental nerve transection, providing adequate exposure but resulting in nerve damage, lip numbness, and facial scarring. In this paper, we describe a case using a submandibular incision for neck dissection, extending from the mandibular angle to the mental foramen, to fully expose the posterior mandible. The intraoral incision, extending 1 cm beyond the tumor margin, connected with the submandibular incision. Under direct vision, we performed a marginal resection of the mandible, preserving the inferior alveolar neurovascular bundle and the mental nerve, and maintaining at least 1 cm of the inferior mandibular margin. This technique achieved complete tumor removal while preserving mental nerve function and lower lip integrity, reducing surgical difficulty and patient trauma. This approach maintains nerve function and aesthetics as much as possible, with a faster postoperative recovery. In treating gingival SCC of the posterior mandible, it is essential to preserve surrounding healthy tissue and critical anatomical structures, minimizing postoperative complications while ensuring complete tumor resection.

Management Of A Completely Edentulous Hemimandibulectomy Patient With Maxillary Twin Occlusion And Mandibular Hollow Denture Prosthesis- A Case Report

The occurrence of Squamous Cell Carcinoma is high in patients with a history of long term tobacco use. Extensive lesions of the oral cavity may lead to resection of mandible, which can compromise the patient’s functions and esthetics to varying degrees, due to its complex attachments and prominent position in the facial architecture. Prosthodontic rehabilitation of a completely edentulous hemimandibulectomy patient is even more challenging due to a number of compromising factors. Revamping certain basic principles of Prosthodontics maybe necessary for successful rehabilitation of these patients. The ultimate aim of the Prosthodontist is to improve the quality of life of these patients, which will not only have a positive physical impact but also enhance the overall mental well being of these patients. This case report presents such a complex scenario of prosthodontic rehabilitation of a completely edentulous hemimandibulectomy patient. Due to the mandibular deviation towards the resected side, incorporation of a maxillary twin occlusion on the unresected side was required to attain a favourable post operative maxillomandibular relation. Due to the extension of the mandibular denture into the defect area in the mandibular region, considerable increase in weight of the mandibular denture was expected, which would have compounded the already existing compromised retention and stability owing to the decreased mandibular denture bearing area. Hence a hollow mandibular denture was planned to reduce the weight of mandibular dentures. Considerable improvement in esthetics and function were noticed and the patient is comfortable and well tolerated with the present prosthesis

Long-term stability of jaw reconstruction with microvascular bone flaps: A prospective longitudinal study

ObjectivesMicrovascular bone flap jaw reconstruction has achieved satisfactory clinical outcomes. However, little is known about the long-term stability of the reconstructed jaw. This prospective longitudinal study aimed to investigate the long-term stability of jaw reconstruction and factors that were associated with it. MethodsPatients with successful computer-assisted osseous free-flap jaw reconstruction in the Department of Oral and Maxillofacial Surgery, Queen Mary Hospital, Hong Kong were recruited for this prospective longitudinal study. The three-dimensional jaw models at the pre-operative plan, post-operative 1-month, and 2 years were aligned and compared. ResultsA total of 69 patients were recruited, among which 48 patients were available for the long-term analysis. Compared to 1-month after surgery, further deviation from the pre-operative plan was observed at post-operative 2 years. Lack of accuracy in surgery, segmental mandible resection especially with the involvement of mandible angles, and post-operative radiation therapy were identified as the significant factors affecting the positional stability of the reconstructed jaw (p < 0.05). Stable reconstruction was observed in the subgroup analysis of patients without post-operative radiation therapy. ConclusionUp to the best of our knowledge, this is the first prospective longitudinal study reporting the long-term stability of jaw reconstruction and its affecting factors. Our data demonstrated that the reconstructed jaw position lacked stability over the postoperative period. How to improve long-term stability of reconstructed jaw thus optimize the functional outcomes warrants further studies.

Virtual planning for mandible resection and reconstruction

Abstract In mandibular reconstruction, computer-assisted procedures, including virtual surgical planning (VSP) and additive manufacturing (AM), have become an integral part of routine clinical practice. Especially complex cases with extensive defects after ablative tumor surgery benefit from a computer-assisted approach. Various CAD/CAM-manufactured tools such as surgical guides (guides for osteotomy, resection and predrilling) support the transition from virtual planning to surgery. Patient-specific implants (PSIs) are of particular value as they facilitate both osteosynthesis and the positioning of bone elements. Computer-based approaches may be associated with higher accuracy, efficiency, and superior patient outcomes. However, certain limitations should be considered, such as additional costs or restricted availability. In the future, automation of the planning process and augmented reality techniques, as well as MRI as a non-ionizing imaging modality, have the potential to further improve the digital workflow.

Mandible Reconstruction in a Rural Population: Comparison of Radial Forearm and Free Fibula Flap Outcomes.

Comparison of microsurgical reconstructive options after mandible resection is limited in the literature. Fibula free flaps (FFFs) can be costly and have timing limitations, but dental restoration can be performed, with varied reported rates of completion. The radial forearm free flap (RFFF) with mandible plating may be an alternative in select populations. The purpose of this study was to determine if the RFFF has similar outcomes to the FFF for mandible reconstruction in a rural population. A retrospective review of patients who underwent mandibulectomy from 2017 to 2021 at a single tertiary-care academic institution was performed. Those with FFF or RFFF reconstruction were included. Mandible defects were classified using the Jewer-Boyd H-C-L system. Sixty-eight patients were included with 53 undergoing FFF and 15 undergoing RFFF. Immediate reconstruction was significantly more common with RFFF than FFF (100% versus 64.2%; P =0.01). Lateral mandible defects were most common among both groups (52.9% FFF versus 73.3% RFFF; P =0.04). Osseous defect length was similar (9.5cm FFF versus 7.7cm RFFF; P =0.07), but soft tissue defect size was significantly larger in the RFFF group (28.6cm 2 versus 15.3cm 2 ; P =0.01). Complication rates (47.1% FFF versus 46.7% RFFF; P =0.98) and disease-free status at last follow-up (96.2% FFF versus 80.0% RFFF; P =0.06) were similar. Dental restoration occurred in 21.3% of patients undergoing FFF. Patients undergoing RFFF or FFF reconstruction after mandibulectomy had similar surgical and disease outcomes, with a low rate of completed dental restoration after FFF. Our findings suggest RFFF is a reasonable alternative to FFF for mandible reconstruction in select patients.

How Is a Cutting Guide With Additional Anatomical References Better in Fibular-Free Flap Mandibular Reconstruction? A Technical Strategy.

Computer-assisted surgery is used to design and manufacture cutting guides in mandibular reconstructions with fibula-free flaps. To improve the outcomes of the procedure, the aim of this research was to investigate and compare the accuracy of mandibular reconstruction following the use of 2 versus 3 anatomical reference cutting guides. Eighteen sets of prototype bone models retrieved from an ameloblastoma patient were used for mock operations. The mandibular segmental osteotomies and fibular reconstructions were performed using 2 and 3 anatomical reference cutting guides in vivo surgeries. After reconstruction, the accuracy of the placed reference points was measured by superimposition of computed tomography images. The error in cutting guides when using 2 or 3 anatomical references showed no significant difference. The fibular and condylar errors of the cutting guide between 2 and 3 anatomical references showed no significant difference in every plate type. The difference in screw hole position errors between 2 and 3 anatomical reference cutting guides was not statistically significant. Two anatomical reference cutting guides are sufficient and reasonable enough for mandible resection. However, there were some limitations and errors in our study.

A novel simulation module for segmental mandibulectomy and mandible reconstruction using 3D models

IntroductionMandibular resection and reconstruction are common but complex procedures in head and neck surgery. Resection with adequate margins is critical to the success of the procedure but technical training is restricted to real case experience. Here we describe our experience in the development and evaluation of a mandibular resection and reconstruction simulation module. Methods3D printed (3DP) models of a mandible with a pathologic lesion were developed from imaging data from a patient with an ameloblastoma. During an educational conference, otolaryngology trainees participated in a simulation in which they reviewed a CT scan of the pathologic mandible and then planned their osteotomies before and after handling a 3DP model demonstrating the lesion. The adequacy of the osteotomy margins was assessed and components of the simulation were rated by participants with pre- and post-training surveys. Results52 participants met criteria. After reviewing the CT scan, 34 participants (65.3 %) proposed osteotomies clear of the lesion. This proportion improved to 48 (92.3 %, p = 0.001) after handling the 3D model. Among those with initially adequate margins (n = 33), 45.5 % decreased their margins closer to the ideal, 27.2 % made no revision, 21.2 % widened their margins. 92 % of participants found the simulation beneficial for surgical planning and technical training. After the exercise, the majority of participants had increased confidence in conceptualizing the boundaries of the lesion (69.2 %) and their abilities to ablate (76.5 %). ConclusionsThe structured mandibulectomy simulation using 3DP models was useful in the development of trainee experience in segmental mandible resection. Lay summaryThis study presents the first mandibulectomy simulation module for trainees with the use of 3DP models. The use of a 3DP model was also shown to improve the quality of surgical training.

RESECTION OF AMELOBASTOMA AND IMMEDIATE RECONSTRUCTION WITH MICROVASCULARIZED FIBULAR GRAFT: A CASE REPORT

A 35-year-old female presented an intraoral swelling in the right posterior region of the mandible, which was asymptomatic, with two years of evolution. She presented an anatomopathological report with a previous diagnosis of ameloblastoma, but she was unable complete the proposed treatment due to the COVID-19 pandemic. Clinical examination revealed a granulomatous lesion in the right retromolar region, extending to the vestibular mucosa of elements 46 and 47, together with,bone expansion. A facial tomography showed an expansive, cystic, multilocular lesion, with erosion of the adjacent cortical bone in the right body, angle, and mandibular ramus, measuring approximately 4.6 × 2.2 × 3.7 cm. The patient underwent partial resection of the right posterior mandible with immediate reconstruction of a microvascularized fibular graft and fixation with a reconstruction plate. In the postoperative period, the patient evolved with satisfactory mandibular contour, good mouth opening, and preserved masticatory function. A 35-year-old female presented an intraoral swelling in the right posterior region of the mandible, which was asymptomatic, with two years of evolution. She presented an anatomopathological report with a previous diagnosis of ameloblastoma, but she was unable complete the proposed treatment due to the COVID-19 pandemic. Clinical examination revealed a granulomatous lesion in the right retromolar region, extending to the vestibular mucosa of elements 46 and 47, together with,bone expansion. A facial tomography showed an expansive, cystic, multilocular lesion, with erosion of the adjacent cortical bone in the right body, angle, and mandibular ramus, measuring approximately 4.6 × 2.2 × 3.7 cm. The patient underwent partial resection of the right posterior mandible with immediate reconstruction of a microvascularized fibular graft and fixation with a reconstruction plate. In the postoperative period, the patient evolved with satisfactory mandibular contour, good mouth opening, and preserved masticatory function.

PROSTHETIC TREATMENT OF PATIENT WITH MANDIBLE RESECTION

Background: Literature findings indicate an increase in mandible resection cases. Retention and stability of dentures are the main issues in the prosthetic treatment of these defects. Aim: The aim of the presented clinical case is to explore the possibility of prosthetic treatment of a patient with mandible resection of the frontal area. Materials and methods: The clinical case monitors the prosthetic treatment of a 38-year-old patient with mandible cancer and resection in the frontal zone. The treatment plan was based on taking preliminary alginate impressions and developing gypsum models. It is planned to develop a partial acrylic denture sealed with silicone material. Additional preparation of the gypsum master model in the resection area took place in order to achieve the equal thickness of the special silicone material. The base of the alveolar bone was restored with hard plaster. In addition, the occlusal rim was fabricated with the purpose of establishing the centric relation and occlusal relationship. The denture was fabricated by acrylic resin with a low quantity of residual monomer and adjusted after adding silicone material over the resected part with functional tests to complete the design of the defect area. Results: The accessed treatment results indicate good retention and stability of the denture. The application of silicone material provided a non-traumatic transition of the masticatory pressure without decubital ulcers in the resected zone. Conclusion: The application of appropriate prosthetic treatment methods in patients with mandible resection leads to the successful restoration of feeding and speaking functions.

Is All-on-four effective in case of partial mandibular resection? A 3D finite element study

IntroductionThe aim of the work is to analyze stress distribution on 3D Finite Element (FE) models at bone, implant, and framework level of different designs for fixed implant-supported prostheses in completely edentulous patients, comparing results on whole and partially resected mandibles. Materials and methods3D anisotropic FE models of a whole and of a partially resected mandible were created using a TC scan of a cadaver's totally edentulous mandible. Two types of totally implant-supported rehabilitation were simulated, with four implants: parallel fixtures on whole mandible and on resected mandible, All-on-four-configured fixtures on whole mandible and on partially resected mandible. A superstructure comprising only metal components of a prosthetic framework were added, while stress distribution and its maximum values were analyzed at bone, implant, and superstructure level. ResultsThe results highlight that:(1) implant stresses are greater on the whole mandible than on the resected one;(2) framework and cancellous-bone stresses are comparable in all cases;(3) on the resected mandible, maximum stress levels at the cortical-bone/implant interface are higher than in whole-mandible rehabilitation. The opposite applies for maximum stresses on external cortical bone, measured radially with respect to the implant from the point of maximum stress at the interface. DiscussionOn the resected mandible, All-on-four configuration proved biomechanically superior to parallel implants considering radial stresses on implants and cortical bone. Still, maximum stresses increase at the bone/implant interface. A design with four parallel implants minimizes the stress on a resected mandible while, on the whole mandible, the All-on-four rehabilitation proves superior at all levels (bone, implant, and framework).

Reconstruction Plate Fracture: Mechanism and Recent Advances

Reconstruction plates with or without bone grafts are used to restore mandibular continuity, form and function following segmental resection of mandible. Fracture of reconstruction plate is observed in 2.9 % to 10% of cases reported in the literature excluding other complications. In this case, we report the fracture of stainless steel reconstruction plate used without bone graft and its management using locking reconstruction plate with non vascularised iliac crest graft following removal of the fractured plate. Review of literature describing incidence, pattern and causes of reconstruction plate fracture and its management is discussed.

Microsurgical Reconstruction of Extensive Lower Lip Defects: An Algorithm for Free Flap Selection and Functional Outcomes.

Large defects of the lower lip pose a difficult challenge for any reconstructive surgeon. When there is limited local tissue available to resurface the defects, free flaps are the preferred option. We reported our experience in the reconstruction of extensive lower lip defects. The authors propose a new algorithm for microsurgical technique selection and assessment of the functional outcomes obtained. A retrospective review of all microsurgical reconstructions of extensive lower lip defects by the senior author for 10 years was performed. The functional outcomes assessed included speech, feeding, and oral continence. Patients were stratified according to their status of simultaneous mandible resection (none, marginal, segmental). Fifty-one patients were included in this study. Almost all patients (96.1%) achieved intelligible speech. Only 1 patient experienced severe drooling. Most patients could eat a solid or soft diet (72.5%). Mandible resection was associated with the worst feeding outcomes. Microsurgical reconstruction of extensive lip defects is safe and provides good results. Free flap selection should take into account the location of the defect, the resected structures, and the body mass index of the patient. Feeding status seems to be inversely correlated with the amount of mandibular resection.

PLAST Classification of Mandibular Duplication and Associated Anomalies

Mandibular duplication is a rare subtype of craniofacial duplication. It is often associated with other anomalies including cleft palate, lingual duplication, and macrostomia. We present an 8-year-old female who had mandibular duplication presenting soon after birth with tongue-based airway obstruction. She was found to have cardiac abnormalities, split sternum, accessory tongue, cleft palate, and accessory submandibular gland. She underwent surgical correction including resection of the duplicated mandible, tongue, and submandibular gland as well as tongue lip adhesion at 12 days old. Post operatively, we were able to avoid tracheostomy and she was able to undergo successful correction of her cardiac anomaly. Literature review found 29 patients with mandibular duplication. Patients with w-shaped (type I) mandibular duplication are more likely to have airway compromise requiring intervention. Several associated anomalies were seen in patients with mandibular duplication. After analysis, we propose the PLAST classification to describe common findings: cleft Palate, Lip duplication, Airway obstruction, Salivary gland abnormalities, and Tongue duplication. Extra craniofacial anomalies such as cardiac and spinal anomalies were also noted in several patients.

Squamous Cell Carcinoma Arising From Odontogenic Cyst Epithelium or Oral Mucosa Epithelium After Marsupialization of Odontogenic Radicular Cyst in Posterior Mandible?

Squamous cell carcinomas (SCCs) are common malignant tumors in the oral and maxillofacial region. However, SCCs secondary to marsupialization of odontogenic radicular cysts are extremely rare. The authors report an unusual case of a 43-year-old male presented with dull pain in the right molar region of the mandible without numbness of lower lips, who had a long history of smoking, alcohol consumption, and betel nut chewing. Computerized tomography revealed a round well-defined unilocular radiolucent at the apex of lower right premolars, 2 nonvital teeth. The clinical diagnosis was the radicular cyst of the right mandible. The patient was initially treated with root canal therapy of the teeth followed by marsupialization with a mandibular vestibular groove incision. While the patient did not follow the instruction of irrigation of the cyst and had no regular follow-up. The reexamination of computerized tomography indicated a round well-defined unilocular radiolucent at the apex of lower right premolars and filled with a soft tissue without clear boundary with buccal muscles at 31 months follow-up. There were no masses or ulcer around the mandibular vestibular groove incision and the patient had no sign of numbness of lower lips. The clinical diagnosis was the radicular cyst of right mandible with infection. A curettage was performed. However, the pathologic diagnosis was well-differentiated SCC. An extended radical surgical resection including segmental resection of the right mandible was performed. The histopathology was well-differentiated SCC without the cyst epithelium and invasion of bone, which can be distinguished from primary intraosseous SCC. The case indicates that marsupialization performed in patients with a history of smoking, alcohol consumption, and betel nut chewing, has a risk of suffering from oral SCC.

Controlling and Stabilising Mandible During Reconstruction: Significance and Techniques.

Stable and accurate positioning of condyle in the glenoid fossa is necessary for maintaining occlusion, facial symmetry and normal function of the temporomandibular joint following segmental resection of mandible. In non-reconstructed mandibular segments or those with fractured reconstruction plates the bony defect gets altered due to contraction or inadvertent muscular pull. This paper describes various techniques used to control dentate and edentate segments of the mandible during reconstruction following an ablative procedure. Secondary mandibular reconstruction has always been a tedious task for the surgeons. Several techniques have been described in literature ranging the use of external fixators, gunning splints and dentures for stabilising mandibular segments. Use of a pre-bent and adapted reconstruction plate is a common practice but may not be feasible in malignancies, benign tumours causing expansion and secondary reconstruction. The current advances in virtual surgical planning allows mandibular reconstruction to be performed in a simpler yet predictable manner. The paper describes techniques ranging from twin K-wire placement to occlusal wafers, 3D printed splints and patient specific implants to enable accurate positioning of the segments and achieve pre-operative form. Advances in virtual surgical planning will continue to allow this field to evolve and to improve the quality of life of the patients.

Bony Canal Method of Dexamethasone Injections in Aggressive Form of Central Giant Cell Granuloma—Case Series

Central Giant Cell Granuloma constitutes approximately 7% of benign tumors of the jaws. The aggressive form of CGCG clinically behaves like a classic semi-malignant neoplasm. In the literature, the suggested method of treatment of aggressive forms of CGCG is curettage or resection with the margin of 0.5 cm. Surgical treatment, especially in the developmental age, entails disturbances in the growth and differentiation of tissues and deforms and disturbs the functioning of the stomatognathic system. Alternative treatment methods of the CGCG presented in this article lead to the patient avoiding a mutilating procedure and improve their quality of life. The aim was to present alternative method of treatment of aggressive forms of Central Giant Cell Lesion of the jaws-injections of dexamethasone into the tumor mass through drilled bony canals. Here, we present the three cases of aggressive forms of CGCG of jaws treated with dexamethasone injections into the tumor mass. Two cases resulted in regression of the tumor, which was confirmed in histologic evaluation after remodeling surgery. Those two patients were uneventful and showed no signs of tumor recurrence at 8 and 9 years of thorough follow-up, respectively. The third patient was qualified for the mandible resection due to the enlargement of the lesion and destruction of the cortical bone. According to our observations, if the proper patient discipline, and thorough, careful clinical and radiological examinations are provided, the dexamethasone injections could be a recommended method of treatment of intraosseous giant cell granuloma. The indication is restricted to the cases with preserved bony borders despite deformation. Additionally, leaving vital teeth in the lesion is also possible.

Intraoral versus transcervical approaches in mandibular reconstruction with free flaps: A retrospective study

This study aims to investigate the clinical and functional differences between intraoral and transcervical approaches for segmental mandible resection and reconstruction with free flaps. Patients diagnosed as benign and low-grade mandibular malignant tumors without neck dissections were retrospectively reviewed and divided into intraoral and transcervical groups. Patients of intraoral group underwent intraoral mandibulectomy and vascular anastomosis was performed through a 2-cm submandibular incision, while traditional submandibular approach was used in transcervical group. Clinical characteristics of two groups were assessed including body mass index (BMI), defect types and number of fibular segments, as well as perioperative variables such as operation time, blood loss, drainage volume. The score of appearance, swallowing and speech using the University of Washington Quality of Life Questionnaire (UW-QOL) was recorded and analyzed 6-month postoperatively.A total of 14 patients in intraoral group and 21 patients in transcervical group was collected, respectively. In intraoral group, intraoperative blood loss and postoperative drainage volume were significantly reduced in comparison with transcervical group (p = 0.0146, p = 0.0017; respectively). The score of appearance was 87.50 ± 12.97 in intraoral group, which was significantly higher than 64.29 ± 12.68 in transcervical group (p < 0.0001). Similar results were found in patients of subtype Class II mandibular defect between two groups. However, patients of intraoral group had a significant increase in operative time and a comparable amount of intraoperative blood loss (p = 0.0472, p = 0.1434; respectively).Within the limitations of the study it seems that an intraoral approach combined with a 2-cm submandibular incision should be preferred over a transcervical approach for segmental mandibulectomy and free flap reconstruction whenever appropriate.

CONVENTIONAL SOLID/MULTICYSTIC AMELOBLASTOMA SURGICAL TREATMENT: CASE REPORT

The present work aims to report the clinical case of a 30-year-old woman attended in the emergency room in April 2020 with a pathologic fracture of the mandible caused by extensive osteolytic injury. The patient reported an evolution of years, a history of incisional biopsy with the conclusion of solid ameloblastoma, and that less invasive treatments such as decompression and marsupialization were tried without success. On tomographic examination, the patient presented a fracture of the mandible in the branch and an expansive tumoral lesion in the branch and right body. The patient underwent emergency surgery with partial resection of the extensive mandible and temporary reconstruction of the mandibular perimeter with a 2.4-mm system reconstruction plate. The patient evolved with good healing in outpatient follow-up. The present work aims to report the clinical case of a 30-year-old woman attended in the emergency room in April 2020 with a pathologic fracture of the mandible caused by extensive osteolytic injury. The patient reported an evolution of years, a history of incisional biopsy with the conclusion of solid ameloblastoma, and that less invasive treatments such as decompression and marsupialization were tried without success. On tomographic examination, the patient presented a fracture of the mandible in the branch and an expansive tumoral lesion in the branch and right body. The patient underwent emergency surgery with partial resection of the extensive mandible and temporary reconstruction of the mandibular perimeter with a 2.4-mm system reconstruction plate. The patient evolved with good healing in outpatient follow-up.

SEGMENTAL MANDIBULECTOMY WITH MICROVASCULARIZED FIBULAR GRAFT FOR MULTICYSTIC AMELOBLASTOMA TREATMENT: A CASE REPORT

Ameloblastomas are benign tumors of the jaws and account for 80% of odontogenic tumors. Ameloblastomas can be very aggressive and lead to dysfunction, such as facial asymmetry. To minimize recurrence, segmental mandibulectomy is more efficient, but it carries high morbidity. We present a case of a 12-year-old male patient who was referred to the Oral and Maxillofacial Surgery unit with swelling of the left mandible. Histologic examination confirmed the diagnosis of multicystic ameloblastoma. Computed tomography showed a multilocular radiolucent lesion, 5.99 cm long and 4.52 cm wide on sagittal view. The patient underwent a segmental mandible resection with a microvascularized fibula graft fixed by a 2.7-mm reconstruction plate. At 6-month follow-up, the patient has good mouth opening, a satisfactory lower jaw shape, and no pain. Microvascularized grafts are the gold standard for rehabilitation after ameloblastoma resection because they restore function and aesthetics.

Three-dimensional (3D) anatomic location, extension, and timing of severe osteoradionecrosis of the mandible.

BackgroundThe purpose of this study was to describe the topography, extension (volume), and timing of severe osteoradionecrosis (ORN) that required mandible resection in patients previously treated for head and neck cancer at a high-volume Veterans Affairs Medical Center.Materials and methodsThe records from a reference hyperbaric oxygen clinic were retrospectively analyzed (n = 50, 2018–2021). Inclusion criteria were: I) severe ORN defined as progressive ORN that required resection; II) pathologic confirmation of ORN; and III) availability of pre-operative CT-imaging. Using a radiotherapy (RT) imaging software, we performed a detailed volumetric (3D) analysis of the bone involvement by ORN. Time intervals from RT to surgery for ORN and from surgery to the last follow-up were calculated.ResultsAll patients that met inclusion criteria (n = 10) were male with significant smoking history (median 47.5 pack-years) and a median age of 57 years old at the time of RT. The primary tumors were: oropharynx (n = 6), oral cavity (n = 3) and nasopharynx (n = 1). The median time from RT to ORN surgery was 8 years. The most common ORN location was the posterior lateral body (molar) and six patients had associated fractures. The mean ORN volume was 3.6 cc (range: 0.6–8.3), corresponding to a mean 6.3% (range: 0.7–14) of the total mandibular volume. After a median follow-up of 13.5 months, no recurrence of ORN occurred. Three patients died of non-cancer and non-ORN-recurrence related causes (1 y OS 77.1%).ConclusionSevere ORN occurred after a median of 8 years from the previous RT and usually affected the posterior lateral body. Surgical resection achieved excellent ORN control.