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The purpose of this multicentre study was to evaluate the efficacy of the 'dredging-marsupialization-curettage' (D-M-C) strategy in the treatment of conventional intraosseous ameloblastoma of the mandible. A total of 31 patients from three institutions, who had a pathological diagnosis of conventional ameloblastoma of the mandible, were treated with the D-M-C strategy. The surgical protocol comprised a dredging and marsupialization (D-M) step, with additional D-M steps as required. The patients then underwent curettage (C) once an obvious effect of the D-M step had been achieved during follow-up. Eight patients were followed up for ≥36 months but <60 months, while 23 were followed up for ≥60 months. Nineteen of the 23 patients followed up for ≥60 months were disease-free at the last follow-up, with no evidence of recurrence. The D-M step is effective for reducing the tumour size and preserving vital structures. The D-M-C surgical strategy may be a feasible treatment option for conventional ameloblastoma of the mandible., (Copyright © 2024 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

The deep circumflex iliac artery (DCIA) flap is one of the bone flaps commonly used for mandibular reconstruction. Observation of the skin paddle and Doppler ultrasound are methods that are usually used to monitor DCIA flaps after mandibular reconstruction surgery. The aim of this study was to introduce a novel DCIA flap with a perforator-supported external oblique abdominal muscle (EOAM) island for postoperative flap monitoring. This study included five patients who underwent mandibular reconstruction using this modified technique. The DCIA flap and the EOAM island supplied by the ascending branch of the DCIA were harvested during the surgery. After mandibular reconstruction, the EOAM island was placed in the submandibular region to monitor the blood supply to the DCIA flap after surgery. The blood supply to the DCIA flap was monitored by observing the colour, texture, and bleeding condition of the EOAM island. After the monitoring period, the EOAM was removed and the ascending branch of the DCIA was ligated. The outcome was successful in all patients. The EOAM island supported by the ascending branch of the DCIA is reliable and safe, thus providing a robust option to monitor the blood supply to the DCIA flap., (Copyright © 2023 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Intraosseous schwannoma of the mandible is rare, with diagnostic and therapeutic challenges. The aims of this study were to report new cases of intraosseous schwannoma of the mandible and to propose a clinical classification, providing suggestions for treatment methods. The cases of 13 patients treated at the authors' hospital and 86 cases reported previously in the literature were reviewed. The most common clinical feature was facial swelling (60/93). The rate of cortical thinning or expansion was 44.8% (43/96); widening of the inferior alveolar nerve canal on radiographs was observed in 15 patients., Competing Interests: Competing interests None., (Copyright © 2023 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Surgical treatment of tumours in the anterior mandible and surrounding tissues may result in defects which can be restored by a fibula free flap. The upper airway may change during this process. The purpose of this retrospective study was to evaluate upper airway changes after fibula free flap reconstruction. A total of 37 patients who underwent anterior mandibulectomy and fibula free flap reconstruction between 2012 and 2020 were recruited. Patients with benign and malignant tumours involving the anterior mandible were included. Spiral computed tomography was performed 1 week preoperatively, 1 week postoperatively, and at> 1 year (range 12-23 months) after surgery. Cross-sectional areas and volumes of the upper airway were measured. Data were analysed by two-way analysis of variance. The upper airway in the malignant tumour group showed an increasing trend, especially at the soft palate and tongue base levels (P < 0.01). In the benign tumour group, the upper airway showed no significant changes. The location of the minimum cross-sectional area moved downwards in both groups, and the area increased in the malignant tumour group during long-term follow-up. Upper airway obstruction is less likely to occur in the long term after surgical resection of anterior mandible malignancies and fibula free flap reconstruction., (Copyright © 2022 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Unsuccessful mandibular reconstruction occasionally occurs, leaving the patient with undesirable function and contours. In such cases, second- or third-time corrective operations are challenging. However, published studies on the complicated retreatment of such patients are scarce. A retrospective analysis covering the years 2015-2019 was conducted in three centers. All 17 patients included had undergone prior failed mandibular reconstructions in other institutions. Salvage secondary or tertiary reconstructive surgeries were attempted and the results are presented. Major factors for these failed reconstructions included exposed non-vascularized bone grafts (n = 7, 41.2%), flap loss (n = 4, 23.5%), exposed artificial joint (n = 3, 17.6%), skewed occlusion with deformity (n = 1, 5.9%), non-union (n = 1, 5.9%), and recurrence (n = 1, 5.9%). Fibula flaps were transferred in 15 patients, while iliac flaps were used in two patients for mandibular re-do reconstructions. Virtual surgical designs were conducted in nine (52.9%) patients, with navigation-guided approaches performed in three cases. Postoperative functions were relatively favorable in these complicated mandibular re-do reconstruction cases. Mandibular symmetry (mandibular length and height; P = 0.002) and condylar position (P < 0.001) were regained after these re-do attempts. Secondary or tertiary mandibular re-do reconstruction can still achieve good functional outcomes with appropriate preoperative selection and well-conceived designs, especially with the aid of virtual surgery and navigation., (Copyright © 2021 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Unicystic ameloblastoma is a unique histopathological type of ameloblastoma, and treatment is controversial. Marsupialisation is effective in reducing the size of cystic lesions and their complications. We have retrospectively analysed the clinical, histopathological, and prognostic data of affected patients who were treated by marsupialisation between 2003 and 2013 in three Chinese hospitals. Our aim was to evaluate the effects and prognosis, and the factors associated with outcome. A total of 116 patients with mandibular unicystic ameloblastomas were included, and 74, 26, and 16 patients were histopathologically classified as being luminal, intraluminal, and mural subtypes, respectively. Most responded well to marsupialisation, with an overall recurrence rate of 12%. Resorption of the root (p<0.001), perforation of the cortical bone (p=0.005), and histopathological subtype (p=0.013) were the main factors that predicted the outcome. Perforation of the cortical bone was the only reliable predictor of recurrence (p<0.001). Disease-free survival function curves indicated that patients with the mural subtype were at a higher risk of recurrence than patients with the other two subtypes (p=0.003). Poor outcomes of marsupialisation were treated surgically and, to date, no subsequent recurrences have been reported. Marsupialisation is effective for these patients, with a recurrence rate similar to that of radical treatment. The outcomes can be predicted using characteristics of the lesion such as resorption of the root, perforation of the cortical bone, and histopathological subtypes. However, additional studies are required to corroborate these findings., (Copyright © 2019 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Regression of metastatic melanoma is very rare and occurs in only 0.23% of cases. Metastasis to the oral cavity is particularly uncommon and accounts for only 1-3% of all oral malignancies. This report presents a case of spontaneous and complete regression of a metastatic melanoma in the mandibular ramus. The patient remains asymptomatic more than 2 years after diagnosis. The patient was followed up regularly. It is recommended that further surveillance imaging be performed in asymptomatic patients following discussion with the surgical and oncological teams. This type of surveillance, together with new systemic treatments, is advocated due to its potential to increase long-term survival even after relapse., (Copyright © 2018. Published by Elsevier Ltd.)

Conservative treatment of odontogenic tumours with decompression or marsupialisation is not common, but can be done successfully in those with a cystic pattern. We present a calcifying epithelial odontogenic tumour that was treated by tube decompression and subsequent enucleation., (Copyright © 2018 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Resection margins are frequently studied in patients with oral squamous cell carcinoma and are accepted as a constant prognostic factor. While most evidence is based on soft tissue margins, reported data for bone resection margins are scarce. The aim of this retrospective study was to evaluate and determine the utility of surgical margins in bone resections for oral cavity squamous cell carcinoma (OCSCC). The status of bone resection margins and their impact on survival was investigated in patients who had undergone segmental mandibulectomy for OCSCC. Medical records were retrieved for the years 2000-2012; 127 patients were identified and included in the study. Tumour-positive bone resection margins were found in 21% of the patients. The 5-year overall survival was significantly lower in this group (P<0.005). Therefore, there is a need for intraoperative feedback on the status of bone resection margins to enable immediate additional resection where necessary. Although the lack of intraoperative methods for the evaluation of bone tissue has been addressed by many authors, there is still no reliable method for widespread use. Future research should focus on an objective, accurate, and rapid method of intraoperative assessment for the entire bone resection margin to optimize patient outcomes., (Copyright © 2018 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

We have introduced an effective treatment for mandibular condylar osteochondroma with a digital cutting guide and endoscopically-assisted vertical ramus osteotomy (VRO). Eleven patients with unilateral condylar osteochondroma, who did not require orthognathic surgery or had less than 3mm deviation of the chin and a stable occlusion, were treated during the period April 2013-January 2017 with a digital cutting guide and endoscopically-assisted VRO. Clinical data collected included the occlusion, facial contour, and maximum mouth opening (MMO). Computed tomographic (CT) scans were taken before and after operation. Two patients also had additional shaping of the mandibular contour. The pathological diagnosis was confirmed to be osteochondroma in all cases. A mean (range) 19 (12-40) months of follow-up for all 11 cases showed stable postoperative occlusion and facial aesthetics. There were no functional disturbances, recurrence, or condylar absorption. VRO is an alternative to orthognathic surgery for patients with osteochondroma who do not have severe malocclusions. The digital cutting guide and endoscopically-assisted VRO make it possible to achieve precise resection of the tumour and maintain the occlusion with minimal invasion., (Copyright © 2018 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

To our knowledge this is only the second reported case of a cystadenoma that arose in the mandible. These are rare benign epithelial neoplasms of the salivary gland that comprise 0.8%-6.3% of all minor tumours of the salivary gland. Because cystadenoma of the mandible is so rare, there is little evidence or guidance about management, and enucleation remains the recommended treatment. Careful histological diagnosis is important for differentiation from other morphologically similar salivary gland tumours such as a mucoepidermoid carcinoma., (Copyright © 2018 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The aim of this study was to assess the management of the condyle during the restoration of mandibular defects following tumour resection. A total of 41 patients who underwent simultaneous tumour resection and reconstruction with vascularized iliac myocutaneous flaps for mandibular defects, from September 2010 to October 2014, were included. These patients were divided into three groups: group 1, condyle preserved; group 2, condyle sacrificed; group 3, condyle frozen. Patients were followed up at 1, 3, 6, and 12 months for the evaluation of appearance, occlusion, and speech. The TMJ disability index (DI) and craniomandibular index (CMI) differed significantly according to the method of management, as well as the position and morphology of the reconstructed condyle (P<0.01); however, no statistically significant difference in mandible movement was observed between the groups. The DI and CMI values were significantly lower in group 1 patients compared to group 2 and group 3 patients. The results showed that TMJ function in group 1 patients was superior to that in group 2 and group 3 patients, and that function in group 3 patients was better than that in group 2 patients. In conclusion, the condyle should be preserved when benign mandibular lesions are situated near the condyle, as preservation has a positive effect on TMJ function and mandible movement., (Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Desmoplastic fibromas are rare, benign, but aggressive lesions, affecting predominantly young people, with an affinity for the mandible. Four patients with desmoplastic fibromas of the mandible, seen between 1995 and 2015 with long-term follow-up, were identified. Three were treated by wide mandibular resection and immediate reconstruction with rib grafts, and one was treated with chemotherapy. In the three resected cases, there has been no recurrence and all rib grafts were successfully incorporated. The case treated by chemotherapy has persistence of the tumour, but it is not progressing. Desmoplastic fibromas in young children respond well to wide mandibular resection and immediate reconstruction with rib grafts. Chemotherapy may halt progression., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Surgical guides have been used widely in maxillofacial surgery. Details of the types of digital surgical guide used in mandibular resection and reconstruction with fibula flaps at the authors' institution are presented in this article. Three patients diagnosed with mandibular ameloblastoma underwent mandibular resection and reconstruction with fibula flaps using surgical guides for assistance. These digital surgical guides included a mandibular osteotomy guide, a fibular osteotomy guide, and a mandibular fixation guide. Surgical guides are helpful in improving the accuracy of operations and are appropriate for many types of mandibular resection and reconstruction., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Osteochondromas (OC) in the craniofacial region are very rare. Following on from a literature review published in 2011, further single case reports and case series are reviewed herein. To date, approximately 235 studies on OC of the mandibular condyle have been published in the English language literature. There is debate regarding the surgical techniques for treatment. Whereas the use of condylectomy has shown no recurrences, follow-up of conservative excision of the tumour has shown recurrence in three cases. One of these relates to the case presented here, which was first reported in 2002. The patient has declined any further surgery since that date. The tumour has shown no further growth and there is no functional impairment. This underlines Cottrell's claim that excision of the entire cartilage cap appears to stop the growth of the tumour and represents the most important focus of surgical treatment., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Ewing sarcoma (ES) of the jaw bones comprises a small fraction of ES at all sites. Due to their rarity, a specific policy for local treatment is lacking. The aim of this study was to evaluate the local therapy for ES and recommend measures to individualize treatment options. Patients with primary non-metastatic ES of the jaw bones treated between August 2005 and February 2015 were analyzed. All patients received primary induction chemotherapy, following which lesions amenable to resection based on specific radiological criteria were resected; those with unresectable lesions were offered definitive radiotherapy. The maxilla was the primary site in 13 patients and the mandible in eight. The median age of patients was 11.6 years (range 5-17 years). Overall, surgery was performed in 17 patients and definitive radiotherapy was used in four patients. Postoperative radiotherapy was administered to 12 patients and was avoided in five patients with 100% tumour necrosis. The 3-year overall survival, event-free survival, and local control were 68.1%, 63.6%, and 80.2%, respectively. Mandible primary and a histological response to chemotherapy were significant prognostic factors. The stratification of patients based on radiological criteria aids in selecting local therapy. In eligible patients, surgery with contemporary reconstruction results in optimal oncological and functional outcomes. Surgery also has the added advantage of identifying patients who may not need radiotherapy., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Resecting neoplasms involving the infratemporal space has a high risk of damaging critical nerves and vessels, in addition to joint form and function. The purpose of this study was to introduce a novel approach to lesions medial to the condyle, which comprises a condylectomy with anterior displacement of the condyle. The indications evaluated using digital surgical simulation, the critical surgical technique, and the preliminary clinical effects are presented here. Five cases underwent this approach between January 2006 and December 2014. The common characteristics of the five masses were (1) that they were non-malignant neoplasms involving the posterior-medial region of the condyle; (2) the upper and lower borders were between the skull base and the lingula, while the anterior border did not exceed the coronoid process. All masses were resected successfully with no damage to any critical nerves or vessels. The average follow-up period was 29.8 months (range 6-56 months). There was no recurrence, secondary deformity, or facial paralysis. The average mouth opening improved from an original 27 mm to 34 mm after surgery. The condyles were well fixed, with no resorption, as shown on computed tomography scans., (Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The purpose of this study was to sequentially evaluate bone union of fibular grafts in mandibular reconstruction. Patients who underwent routine follow-up computed tomography (CT) and panoramic X-ray imaging during a period of ≥2 years were enrolled. On panoramic X-ray images, bone union was scored as 0 (absent callus formation) or 1 (complete callus formation). On CT images, a scale of 0 to 2 was used (0, absent callus formation; 1, complete callus formation only on the labial side; 2, complete callus formation on both the labial and lingual side). A total of 56 bone junctions were evaluated in 20 patients. Five of 56 junctions (9%) in four of 20 patients (20%) showed radiological non-union (panoramic X-ray score=0, CT score=0 or 1) at 2 years after surgery. All bone junctions with radiological non-union were located at the mandibular angle. No categorical values, including diabetes mellitus and radiation therapy, were significantly associated with radiological non-union. In conclusion, assessing at least two sides (i.e. labial and lingual sides) on CT images is adequate to evaluate bone union in transferred fibula flaps. Careful fixation at the mandibular angle may improve the rate of bone union., (Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Ameloblastoma is a benign, slow-growing neoplasm of the jaw that arises from odontogenic epithelium. We present the case of a 7-year-old girl with a unicystic ameloblastoma of the mandible, and describe our approach to treatment., (Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Clear cell odontogenic carcinoma (CCOC) is a rare neoplasm; only 75 cases have been reported in the English language literature. They have a tendency for recurrence and a capacity to metastasize. There is very little known regarding the metabolic features of this tumour or the utility of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scans in the staging and follow-up of these tumours. We present two cases of CCOC with their relevant FDG-PET/CT scan findings. The first patient had primary CCOC of the mandible that was FDG-avid, and the other had recurrence of CCOC of the anterior mandible and superomedial orbit that was not FDG-avid. FDG uptake in CCOC appears to be variable. Although FDG-PET/CT is useful in other head and neck cancers and has benefits compared to other imaging modalities, further studies are needed to investigate the sensitivity of FDG-PET/CT in CCOC., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)

Marsupialisation, by which a surgical window is created in the cavity of a cystic lesion, has been recommended to avoid the formation of a bony defect in the jaw and a reduction in a patient's quality of life. However, information about the factors that affect the reduction in the size of a cyst after marsupialisation is limited. We have studied the effects of the patient's age and the size of the primary lesion on the speed of shrinkage after marsupialisation of keratocystic odontogenic tumours (KCOTs), dentigerous cysts, and radicular cysts. The speed of shrinkage (mm(2)/month) was evaluated by measuring the radiolucent area on panoramic radiographs taken before and after marsupialisation for KCOT (n=28), dentigerous cysts (n=26), and radicular cysts (n=18) in the mandibular molar regions. The mean duration of marsupialisation for each type of cyst was 11 (5), 8 (5), and 5 (2) months, respectively. The radiolucent area decreased linearly in the 3 types depending on the time after marsupialisation: r=-0.86 (p<0.01), r=-0.73 (p<0.01), and r=-0.72 (p<0.01), respectively. The relative speed of shrinkage did not correlate with the age of the patients, though it did correlate with the size of the radiolucent area before marsupialisation in KCOT (r=0.69, p<0.01) and radicular cysts (r=0.73, p<0.01). These results suggest that the size of a cyst before marsupialisation may affect the speed of shrinkage in KCOT and radicular cysts, while the age of the patient does not., (Copyright © 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Osteoid osteoma is a rare benign osseous neoplasm which rarely affects the jaws. It is more common in long bones which can lead to postural scoliosis. The clinical characteristic feature of this tumour is the unexplained pain that is relieved by the intake of analgesics. Histologically it is characterized by the formation of central nidus with surrounding sclerotic bone. The diagnostic dilemma in this case report is aggravated by its unusual association with the teeth. The use of CT scanning is advised to distinguish from other odontogenic tumours. Treatment for this tumour is surgical removal or excisional biopsy to avoid recurrence and progression to malignant changes., (Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

A 73-year-old man presented with a painful swelling of the left temporomandibular joint with no other symptoms. Panoramic radiography showed an osteolytic lesion in the left mandibular body, while magnetic resonance imaging provided the most accurate view of an osteolytic lesion in the left condyle. Skeletal scintigraphy showed increased uptake in the mandibular anatomical area. A diagnosis of metastatic breast adenocarcinoma was made from mandibular biopsies which proved to be ductal carcinoma, with no evidence of any other metastases. Clinicopathologic features of this case are reviewed., (Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The purpose of this study was to determine how keratocystic odontogenic tumours (KCOTs) in the mandible are reduced during marsupialisation, and to predict the best time for secondary enucleation by analysing computed tomography (CT) images. 15 patients with KCOTs were treated with marsupialisation surgery, and 42 series of CT data taken during the marsupialisation process were analysed. CT data were reconstructed in three-dimensional (3D) images. The 3D images were used to measure the diameter and volume, and to analyse the changes that occurred after marsupialisation. Marsupialised KCOTs tended to be reduced equally towards the window in the tumour. The amount of volume reduction per day (V(r)) was reduced in proportion to the volume (V) with the formula V(r)=-0.0029×V. The formula manipulation for V was V=V(0)×e(-0.0029t) (t=duration after marsupialisaton (day)). The volume of marsupialised KCOTs was reduced by half over a 239 day cycle. These results demonstrate that the future shape of marsupialised mandibular KCOTs, under good control, could be predicted with significant accuracy using CT data. This prediction could decrease the prolonged marsupialisation state in patients with KCOTs., (Copyright © 2011 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

This preliminary retrospective study evaluates the diagnostic value of cone-beam computed tomography (CBCT), as a potential standard preoperative procedure, in assessing mandibular invasion by oral squamous cell carcinoma (OSCC) compared with conventional preoperative panoramic radiography (PR), magnetic resonance imaging (MRI) and histological examination of the resection specimen (the golden standard). Between September 2006 and September 2009, 23 patients with histology proven primary OSCC, adjacent to or fixed to the mandible were included. The tumours were classified into four groups, ranging from no bone invasion to evident bone invasion. Sensitivity and specificity for PR were 55% (95% CI [0.350;0.619]) and 92% (95% CI 0.737;0.984]), respectively, both were significantly lower than the 91% (95% CI [0.740;0.909]) and 100% (95% CI [0.845;1]), respectively, for CBCT. MRI showed 82% sensitivity (95% CI [0.608;0.941]) and 67% specificity (95% CI [0.474;0.779]). CBCT has the potential to become a new diagnostic tool in the OSCC screening procedure to predict mandibular invasion or erosion, but its value may be limited by its relatively low sensitivity. A prospective study will start on 64 patients (alpha=0.05; power 0.8; effect size 0.5) to improve these results statistically., (Copyright 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Central mucoepidermoid carcinoma is a rare mandibular neoplasm. The objective of this paper was to report two cases.

A 48-year-old man was referred for investigation of an asymptomatic radiolucent lesion in the mandible. The margin was partly irregular, and there was no peripheral sclerosis. The tumour was composed of histiocytic cells, spindle cells, and fibrous tissue. Immunohistochemical analysis showed that the tumour cells stained for CD68 and vimentin, and not for cytokeratin, smooth muscle actin, S-100 protein, or CD34. The tumour was therefore diagnosed as a benign fibrous histiocytoma.

A new guide for mandibular resection in the management of oral squamous cell carcinoma based on the Cawood and Howell classification of the jaws is suggested. This was a retrospective review of case records and pre-operative orthopantomograms (OPG), bone scintigraphy and magnetic resonance imaging (MRI). The classification of the mandible was based on the residual bone height as measured in the molar region of the OPG to be equivalent to the Cawood and Howell classification of the mandible (Class I-II dentate or immediate post-extraction), Class III-IV >20mm well-rounded or knife-edge ridge, and Class V-VI <20mm (flat or depressed ridge form). Of the 77 patients, 58% (22/38) of Class I-II, 43% (9/23) of Class III-IV and 6% (1/16) of Class V-VI were treated with a marginal (rim) resection of the mandible. The predictability of the pre-operative investigations was more accurate in the edentulous mandible (Class III-VI). A simple guide is suggested for mandibular resection taking into account the pre-operative investigations, the estimation of invasion clinically, and the Cawood and Howell classification of ridge resorption.

Osteomas are benign bone neoplasms, classified as either peripheral or central. The peripheral variant is rare, with only six cases reported involving the mandibular condyle, that are not related to Gardner syndrome. The seventh case of peripheral osteoma involving the mandibular condyle is reported in this paper.

We present a case of haemangioma of the mandible in a 46-year-old woman. The radiological appearance was of a unilocular radiolucency that looked similar to other more common lesions of the mandible. This case shows that a potentially life-threatening haemangioma can present as an apparently benign cyst-like unilocular radiolucency, and highlights the need to include haemangioma in many differential diagnoses, and the importance of taking all radiological features into account.

The method of conservative (rim) resection of the mandible is now well established and provides good control of disease in the primary site. There are few audits of this technique in terms of margins of resection for both rim and segmental resection of the mandible. Consecutive previously untreated patients managed with resection of the mandible as part of their treatment for oral and oropharyngeal squamous cell carcinoma were recruited for the study. The presence and extent of tumour invasion of the mandible was recorded and a retrospective analysis made to establish the incidence of unnecessary segmental resections. The invasion rate was 33% (8/35) for rims and 83% (54/65) in segmental resections of the mandible, which compares favourably with previous studies and indicates a reasonable accuracy of resection. In between 6 and 11 of the 62 cases (10-17%) a rim resection could have achieved a satisfactory resection margin and retained a functioning lower border of the mandible. The accuracy of resection in terms of margins was greater for mandibular resections (94% clear margins) than soft tissues (62% clear margins). The number of compromised margins was significantly greater in the invaded rim resection group (P=0.018). This study indicates that a more conservative mandibular resection was possible in a few cases. This is unlikely to have an adverse effect on the close or involved margin rate, which depends mainly on the accuracy of the soft tissue resection. Angling the horizontal rim resection to take into account tumour entry at the point of contact will help to ensure a clear bone margin if a conservative approach to mandibular resection is an option.

A case of osteochondroma of the right mandibular condyle in a 47-year-old woman is presented. Instead of condylectomy, surgical resection was performed, resulting in fewer functional changes and less dysfunction of the temporomandibular joint but recurrence within 12 months after surgery.

The accuracy of clinical examination, peroperative periosteal stripping and imaging techniques in predicting tumour invasion of the mandible in oral cancer so far reported have been compared according to their specificity and sensitivity. Clinical examination alone was not shown to be accurate, but periosteal stripping at the time of resection was extremely accurate although so far only one study has investigated it. No single imaging technique will accurately predict the invasion of tumour into the mandible, but a combination of an orthopantomogram and bone scintigraphy is recommended in early invasion. Magnetic resonance imaging is more sensitive than computed tomography and therefore may be more useful if mandibular invasion requires consideration. The decision to resect the mandible as part of the management of oral cancer should be taken on the evidence of clinical examination, periosteal stripping and at least two imaging techniques that complement each other in terms of specificity and sensitivity., (Copyright 2001 The British Association of Oral and Maxillofacial Surgeons.)

The spread pattern of a tumour and its extent in the mandible are important in the management of gingival cancer. Sixteen patients with gingival squamous cell carcinoma (SCC) involving the mandible in the molar region were included in this study. Resection specimens of the mandibular bone and adjacent cancer were histologically analysed to identify the type and characteristics of invasion and were compared with the radiological features. Our results showed that the actual width of invasion was underestimated to a greater extent than the actual depth of invasion. For horizontal aspects, four dentate cases had horizontal intramedullary spread underneath intact mucosa or cortical bone extended from the main foci of tumour that infiltrated through the occlusal surface. For vertical aspects, nerve invasion took place in only one of 16 specimens, while five cases showed downward infiltration beyond the inferior alveolar canal without nerve involvement, so that the pattern of tumour spread was mostly transmedullary rather than perineural in previously non-irradiated cases. These cases with deep infiltration showed the infiltrative type of invasion in the dentate mandible. And when the tumour was related with previous dental extractions or curettage, it tended to be more extensive than what was predicted from an imaging point of view. These pathological and clinical features affecting the tumour spread should be considered in the management of gingival SCC in the molar region.

The calcifying epithelial odontogenic (Pindborg) tumour is a rare primary tumour of the jaw with a characteristic histological appearance. We describe here its appearance on computed tomography (an expanding, multilocular lesion that is thinning both plates of the mandible, is well-defined and contains scattered radio-opaque areas) and magnetic resonance imaging (predominantly hypointense on T1-weighted images and of mixed hyperintensity on T2-weighted images; the extent of the tumour including involvement of the mandibular canal was clear)., (Copyright 2000)

Burkitt's lymphoma in a 4-year-old Chinese boy presented with acute mandibular swelling but no associated systemic disturbance. A review of published reports shows that the diagnosis should be suspected in jaw lesions with no obvious cause.

A 52-year-old woman presented with pain on the right temporal region, restricted mandibular movement and a gradually developing malocclusion. Osteochondroma of the mandibular condyle was suspected based on diagnostic imaging. Local resection with preservation of the condylar head resulted in complete resolution of symptoms.

The term 'fibromatosis' is used to denote two main pathological entities: juvenile fibromatosis and adult fibromatosis. It is also possible to distinguish between superficial fibromatosis of the aponeurosis and deep fibromatosis of the muscle-aponeurosis. Histopathological findings have indicated that fibromatosis is an invasive neoformation of fibromatous connective tissue involving adjacent structures. It does not metastasize, though recurrence rates vary. Treatment is based on either excision of the mass, or radiotherapy and chemotherapy if the condition is inoperable. We describe a case of fibromatosis of the mandible in a young girl. The growth was excised completely and she was still disease-free four years later.

A study was performed of 32 oral carcinomas that were diagnosed after recent dental extraction with particular reference to metastasis and survival. Eighty-four per cent of the patients complained of local swelling and/or pain. Infection had been suspected in 74% of the patients by the referring doctors. The involved teeth had been extracted in all patients. Ulceration and granulomatous tissue suggestive of carcinoma were found in the extraction sites in 24 patients when they were referred to us. Radiographs at presentation, available in 26 patients, showed diffuse radiolucencies with irregular borders around the extraction sites. Tumor or carcinoma were the clinical diagnoses in 27 patients. All patients underwent chemotherapy, irradiation and/or surgery, or a combination of these with curative intent after the diagnosis was confirmed histologically. Compared to a group of patients in whom dental extraction was not performed, the incidence of pathologically positive lymph nodes was significantly higher in the extraction group (52% vs 26%). The five-year survival in the extraction group was also lower (35% vs 48%).

In a 12-month period, metastatic cancer was diagnosed in eight patients. Six of them presented with pain mimicking toothache, temporomandibular joint disorders or trigeminal neuralgia, while two showed osteopenic bone lesions in the panoramic radiography, and perimandibular swelling. Anesthesia of the lower lip was the only common clinical feature. In seven of the eight patients, a whole body bone scintigraphy and single photon emission computed tomography (SPECT) of the skull in combination with a whole body and SPECT anti-granulocyte (Tc-99m MAK 250/183) bone marrow scintigraphy was performed. One patient did not have combined scintigraphy performed secondary to severe systemic illness. In six of the seven, the results were conclusive for a metastatic bone lesion. Biopsies confirmed three patients to have a previously unrecognized primary cancer, one patient to have previously unrecognized recurrent cancer, and three patients to exhibit new metastatic spread of an already diagnosed cancer. Histology revealed breast, lung, renal cancer and a malignancy of inconclusive origin. In the remaining patient, combined scintigraphy suggested osteomyelitis, yet biopsy revealed a prostate cancer metastasis with acute inflammatory cell infiltration. Thus, the scintigraphy pattern of a hot spot in the bone scan and a cold lesion in the bone marrow scintigraphy is highly suggestive of a mandibular metastasis, if accompanied by anesthesia of the lower lip.

Osteosarcoma of the jaw bone is comparatively rare and accounts for about 6.5% of all osteosarcomas. We treated eight cases of osteosarcoma of the jaw bone involving the mandible and maxilla in equal proportions between 1986-1992. The median age was 31 years and male: female ratio was 5:3. Swelling and bony expansion were the most common presentations. Radiologically six patients had lytic lesions, and histopathologically they were osteoblastic (n = 4), chondroblastic (n = 3) and fibroblastic (n = 1). Three patients, two with mandibular and one with maxillary osteosarcoma underwent radical surgery and six courses of cisplatinum-based chemotherapy. All were alive and disease free 24, 30, and 54 months after treatment. Histologically all three were chondroblastic. Five patients had incomplete or palliative treatment. All patients died of progressive or locally recurrent disease within 2 years.

The detection in the mandible of early local spreading of adjacent primary malignancies poses a difficult problem. A survey of 60 patients suspected of carcinomatous mandibular infiltration was undertaken, and the most important clinical and imaging data were studied. Tumor localization and bone scintigraphy proved to offer the most important predictive power. A decision tree and a logistic regression model which determines a score function combining these characteristics were designed. This decision tree improves the sensitivity and specificity of the preoperative assessment and provides the surgeon with an algorithm for the accurate estimation of early mandibular invasion.

Osteochondroma of the mandibular condyle is extremely rare and may cause signs and symptoms like those seen in patients with temporomandibular joint dysfunction. Differentiation between osteochondroma and condylar hyperplasia is not possible on histologic grounds alone, but the radiographic and intraoperative findings together are usually sufficient to establish a definite diagnosis.