A rare case of Ewing sarcoma metastasis to the oral cavity.

Ewing sarcoma in the head and neck is rare, and metastasis from other bones to the mandible accounts for 0.7% of cases. This report presents a case of oral metastasis in a 24-year-old male patient diagnosed with Ewing sarcoma of the femur (p53 gene mutation and EWSR1-ERG fusion). The chief complaint was numbness in the mandible and pain for 1 month and a hardened, ulcerated exophytic lesion in the right retromolar region. Imaging exams revealed an unspecified thinning of the cortical bone of the inferior alveolar canal in the right mandibular ramus, associated with erosion of the alveolar bone. Histopathological analysis confirmed metastasis of Ewing sarcoma. The patient presented an aggressive disease progression and died 1 month after the oral diagnosis. It is important to recognize the signs and symptoms compatible with rare clinical outcomes, leading to an early diagnosis that can improve patients' quality of life and survival.

Neurofibrosarcoma of the mandible derived from neurofibromatosis

Neurofibrosarcoma is a rare malignant neoplasm of the head and neck region and accounts for 8% to 16% of all cases. Its origin is varied and may stem from cells of the peripheral nerves, develop de novo, or result from malignant transformation of preexisting neurofibromas. Because the features of neurofibrosarcomas are heterogeneous, the data retrieved during clinical examinations are of great aid for diagnosis. In this case, owing to clinical features and the fact that the patient had neurofibromatosis type 1, the hypothesis of neurofibrosarcoma was promptly established. The final diagnosis was confirmed by associating clinical, imaging, and pathological data. After the treatment, the patient has been followed up for 10 years, with no evidence of recurrence.

Neurofibrosarcoma of the mandible derived from neurofibromatosis.

Neurofibrosarcoma is a rare malignant neoplasm of the head and neck region and accounts for 8% to 16% of all cases. Its origin is varied and may stem from cells of the peripheral nerves, develop de novo, or result from malignant transformation of preexisting neurofibromas. Because the features of neurofibrosarcomas are heterogeneous, the data retrieved during clinical examinations are of great aid for diagnosis. In this case, owing to clinical features and the fact that the patient had neurofibromatosis type 1, the hypothesis of neurofibrosarcoma was promptly established. The final diagnosis was confirmed by associating clinical, imaging, and pathological data. After the treatment, the patient has been followed up for 10 years, with no evidence of recurrence.

Influence of bisphosphonates on clinical features of osteoradionecrosis of the maxilla and mandible.

BACKGROUND AND PURPOSE: Osteoradionecrosis (ORN) is one of the most severe adverse effects of radiotherapy (RT) to the head and neck region. Medication-induced osteonecrosis of the jaw has been reported among patients using bisphosphonates. However, the impact of RT on osteonecrosis in patients using bisphosphonates has not yet been described. Therefore, the aim of this study was to compare ORN characteristics between patients who use and do not use bisphosphonates. MATERIALS AND METHODS: This retrospective study evaluated 96 patients with ORN of the jaw. Patients were divided into group I (patients who did not receive bisphosphonates, n = 83) and group II (patients who did receive bisphosphonates, n = 13). Clinical data were obtained from medical charts. RESULTS: Osteoradionecrosis more often involved the mandibular jaw than the maxillary jaw for both patient groups. However, maxillary involvement was more common among patients who received bisphosphonates than those who did not (p = 0.014). There was also a trend toward earlier development of ORN in the group that received bisphosphonates (p = 0.21). CONCLUSIONS: Bisphosphonate use appears to contribute to earlier development of ORN. Long-term prospective studies are needed to understand the pathogenesis of ORN in patients treated with combined radiation and bisphosphonate therapy.

Gingival complex odontoma: a rare case report with a review of the literature.

Odontomas are odontogenic tumors composed of a mixture of dental tissues. They are very common hamartomas of the jaws. However, their peripheral or gingival counterparts are extremely uncommon. The objective of this article is to report a rare case of gingival complex odontoma in an 11-year-old patient, and also to review all published cases of this type of lesion.

Gingival complex odontoma: a rare case report with a review of the literature

Odontomas are odontogenic tumors composed of a mixture of dental tissues. They are very common hamartomas of the jaws. However, their peripheral or gingival counterparts are extremely uncommon. The objective of this article is to report a rare case of gingival complex odontoma in an 11-year-old patient, and also to review all published cases of this type of lesion.

Avaliação das estruturas ósseas da articulação temporomandibular por meio de imagens de tomografia computadorizada espiral e ressonância magnética / Evaluation of the temporomandibular joint bone structures using spiral computed tomography and magnetic resonance imaging

A articulação temporomandibular apresenta uma complexidade morfofuncional de destaque no organismo humano. Muitas técnicas podem ser utilizadas para o exame das ATMs, no entanto, a ressonância magnética é considerada atualmente a modalidade de exame mais indicada para o estudo da ATM devido a possibilidade do estudo dos tecidos moles, sem a utilização de radiação ionizante. Entretanto, a TC destaca-se principalmente quando são necessários estudos das estruturas anatômicas e suas variações, bem como das afecções que a acometem, dentre os quais os processos degenerativos. Sendo assim, ambas as técnicas de imagem se tornaram padrão para o exame da ATM e se complementam. Diante do conceito de radioproteção do paciente, foi observada a necessidade de testar se as imagens por RM também podem ser úteis para o diagnóstico das alterações ósseas da ATM, com a vantagem de fornecer as imagens de tecidos moles e não ser ionizante. Foram avaliadas imagens de RM e TC de ATM de 56 pacientes sintomáticos (46 do gênero feminino e 10 do gênero masculino, nas faixas etárias entre 18 e 83 anos; média de 43 anos de idade). Foi definido um nível de significância de 0,05 (5%). Todos os intervalos de confiança foram construídos com 95% de confiança estatística. Encontramos relação estatisticamente significante entre os exames de RM e TC em diversas variáveis. Sendo que a acurácia, sensibilidade e especificidade da RM em detectar alterações ósseas se mostrou estatisticamente significante na maioria das variáveis estudadas, sugerindo que é um exame confiável quando se trata de tais alterações.

Mantle cell lymphoma: involvement of nodal and extranodal sites in the head and neck, with multifocal oral lesions.

Mantle cell lymphoma (MCL) is a malignant B-cell neoplasm, which comprises monomorphic and small- to medium-sized mantle zone-derived lymphoid cells. It is characterized by chromosomal translocation t(11;14)(q13;q32) and CCND1 truncation, resulting in cell cycle deregulation. It is an aggressive type of non-Hodgkin lymphoma with a propensity to present with extranodal involvement. This study shows the case of an 80-year-old Caucasian male who complained of a 2-month progressive swelling on the right side of his face. The magnetic resonance imaging exam showed multifocal involvement of the head and neck, including oral manifestations, bilateral parotid glands, palate, tongue, and floor of the mouth. An incisional biopsy of the tumor mass was performed. The morphological and immunophenotypic findings were consistent with the diagnosis of MCL. The patient died 4 months later, without any chance of undergoing a therapeutic approach. Although MCL is a rare condition, it should be subjected to a differential diagnosis when affecting the maxillofacial area. Imaging exams and both immunohistochemical and morphological analyses are needed to reach the correct diagnosis. Here, we present an unusual MCL with multifocal involvement of the head and neck.

Mantle cell lymphoma: involvement of nodal and extranodal sites in the head and neck, with multifocal oral lesions

Mantle cell lymphoma (MCL) is a malignant B-cell neoplasm, which comprises monomorphic and small- to medium-sized mantle zone-derived lymphoid cells. It is characterized by chromosomal translocation t(11;14)(q13;q32) and CCND1 truncation, resulting in cell cycle deregulation. It is an aggressive type of non-Hodgkin lymphoma with a propensity to present with extranodal involvement. This study shows the case of an 80-year-old Caucasian male who complained of a 2-month progressive swelling on the right side of his face. The magnetic resonance imaging exam showed multifocal involvement of the head and neck, including oral manifestations, bilateral parotid glands, palate, tongue, and floor of the mouth. An incisional biopsy of the tumor mass was performed. The morphological and immunophenotypic findings were consistent with the diagnosis of MCL. The patient died 4 months later, without any chance of undergoing a therapeutic approach. Although MCL is a rare condition, it should be subjected to a differential diagnosis when affecting the maxillofacial area. Imaging exams and both immunohistochemical and morphological analyses are needed to reach the correct diagnosis. Here, we present an unusual MCL with multifocal involvement of the head and neck.

Rosai-Dorfman disease affecting the maxilla

Rosai-Dorfman disease (RDD), formerly called sinus histiocytosis with massive lymphadenopathy, is a non-neoplastic proliferative histiocytic disorder with behavior ranging from highly aggressive to spontaneous remission. Although the lymph nodes are more commonly involved, any organ can be affected. This study aimed to describe the features and the follow-up of a case of extranodal RDD. Our patient was a 39-year-old woman who was referred with an 11-month history of pain in the right maxilla. On clinical examination, some upper right teeth presented full mobility with normal appearance of the surrounding gingiva. Radiographic exams showed an extensive bone reabsorption and maxillary sinus filled with homogeneous tissue, which sometimes showed polypoid formation. An incisional biopsy demonstrated a diffuse inflammatory infiltrate rich in foamy histiocytes displaying lymphocytes emperipolesis. Immunohistochemistry showed positivity for CD68 and S-100, and negativity for CD3, CD20, and CD30. Such features were consistent with the RDD diagnosis. The patient was referred to a hematologist and corticotherapy was administrated for 6 months. RDD is an uncommon disease that rarely affects the maxilla. In the present case, the treatment was conservative, and the patient is currently asymptomatic after 5 years of follow-up.

Extensive epidermoid cyst of the submental region.

Epidermoid cysts are malformations that are rarely observed in the submental region. Imaging has an important role in surgical planning according to the size and location of the cyst in relation to geniohyoid and mylohyoid muscles. This article reports the case of a 15-year-old female patient complaining of submental swelling. The differential diagnosis included infection, tumor, ranula, and abnormalities during embryonic development. The lesion was surgically excised using an extra-oral approach. The histopathological examination revealed a cyst wall lined with stratified squamous epithelium with the presence of several horny scales consistent with the diagnosis of an epidermoid cyst. No recurrences were found after 1 year of follow-up.

The relevance of clinical and radiographic features of jaw lesions: A prospective study.

The study was carried out in a Brazilian population and the aim was to describe the prevalence and the clinic-radiographical features of jaw lesions. In addition, a comparison between the main diagnosis hypothesis and final diagnosis was accessed. A prospective study which evaluated all patients with jaw lesions diagnosed in an Oral Diagnosis Center, between August 2013 and October 2014. A total of 450 patients were observed for the first time, and 130 had some type of jaw lesion. The mean age of the patients was 35.2 years ± 17.86. Among these, 71 were women (54.62%) and 87 were Caucasian (66.92%). The mandible was affected more frequently (71.43%) than the maxilla (28.57%). Swelling and pain were the most frequent clinical signs and symptoms and were observed in 60 (42.85%) and 38 (27.14%) cases, respectively. The panoramic x-ray was the main radiographic exam utilized (88.57%). Radiolucent lesions accounted for 89 cases (63.57%) and the unilocular form was present in 114 cases (81.43%). A total of 93 cases had histopathological analyses and the periapical cyst was the most frequent lesion. In the other 47 lesions, the diagnosis was conducted by clinical and radiographic management. Bone lesions were frequent, being noted on first visit in approximately 30% of patients; in 1/3 of the cases, the diagnoses were completed with a combination of clinical and radiographic exams.

Rosai-Dorfman disease affecting the maxilla.

Rosai-Dorfman disease (RDD), formerly called sinus histiocytosis with massive lymphadenopathy, is a non-neoplastic proliferative histiocytic disorder with behavior ranging from highly aggressive to spontaneous remission. Although the lymph nodes are more commonly involved, any organ can be affected. This study aimed to describe the features and the follow-up of a case of extranodal RDD. Our patient was a 39-year-old woman who was referred with an 11-month history of pain in the right maxilla. On clinical examination, some upper right teeth presented full mobility with normal appearance of the surrounding gingiva. Radiographic exams showed an extensive bone reabsorption and maxillary sinus filled with homogeneous tissue, which sometimes showed polypoid formation. An incisional biopsy demonstrated a diffuse inflammatory infiltrate rich in foamy histiocytes displaying lymphocytes emperipolesis. Immunohistochemistry showed positivity for CD68 and S-100, and negativity for CD3, CD20, and CD30. Such features were consistent with the RDD diagnosis. The patient was referred to a hematologist and corticotherapy was administrated for 6 months. RDD is an uncommon disease that rarely affects the maxilla. In the present case, the treatment was conservative, and the patient is currently asymptomatic after 5 years of follow-up.

The relevance of clinical and radiographic features of jaw lesions: A prospective study

Abstract The study was carried out in a Brazilian population and the aim was to describe the prevalence and the clinic-radiographical features of jaw lesions. In addition, a comparison between the main diagnosis hypothesis and final diagnosis was accessed. A prospective study which evaluated all patients with jaw lesions diagnosed in an Oral Diagnosis Center, between August 2013 and October 2014. A total of 450 patients were observed for the first time, and 130 had some type of jaw lesion. The mean age of the patients was 35.2 years ± 17.86. Among these, 71 were women (54.62%) and 87 were Caucasian (66.92%). The mandible was affected more frequently (71.43%) than the maxilla (28.57%). Swelling and pain were the most frequent clinical signs and symptoms and were observed in 60 (42.85%) and 38 (27.14%) cases, respectively. The panoramic x-ray was the main radiographic exam utilized (88.57%). Radiolucent lesions accounted for 89 cases (63.57%) and the unilocular form was present in 114 cases (81.43%). A total of 93 cases had histopathological analyses and the periapical cyst was the most frequent lesion. In the other 47 lesions, the diagnosis was conducted by clinical and radiographic management. Bone lesions were frequent, being noted on first visit in approximately 30% of patients; in 1/3 of the cases, the diagnoses were completed with a combination of clinical and radiographic exams.

Bilateral mandibular osteomyelitis mimicking periapical cysts in a patient with sickle cell anemia.

Sickle cell anemia (SCA) is a hemoglobin disorder that occurs more commonly among Afro-descendants. The authors report the case of a 28-year-old Afro-descendent male patient with the diagnosis of homozygotic sickle cell disease (SCD) referred for evaluation of mandibular lesions. The patient's main complaints included pain and bilateral teeth mobility. An intraoral examination revealed gingiva recession affecting the lower molars with extensive root exposure. A panoramic x-ray showed two radiolucent symmetrical periapical lesions evolving both the first and the second lower molars, bilaterally. The diagnostic hypotheses comprised odontogenic infection, among others. Besides antimicrobial therapy, the two molars of both sides were extracted and bone was collected for histopathological and microbiological analyses. Osteomyelitis was diagnosed, and Streptococcus viridans was recovered from the culture media. Mandibular osteomyelitis should be considered as a diagnosis in patients with SCD. The present case offers an alert to clinicians about the importance of knowing jaw lesions related to SCA.

Osteonecrosis related to once-yearly zoledronic acid treatment in an osteoporotic patient after dental implant.

This paper presents a case of osteonecrosis of the jaw related to zoledronic acid (5 mg) administered once yearly to treat osteoporosis. A 79-year-old woman who has been treated for osteoporosis for 5 years with 5 applications of zoledronic acid was referred for evaluation. The patient had been submitted to dental implant placement and there was no osseointegration. On clinical examination, suppuration and exposed bone on the alveolar ridge were observed. Radiographic examination revealed an osteolytic area and bone sequestration. Both clinical and radiological features were suggestive of osteonecrosis. The treatment consisted of surgery to remove the affected bone completely. The patient is asymptomatic at 9 months after surgery. Dentists and oral surgeons should be alert to the possibility of osteonecrosis related to the use of once-yearly injections of zoledronic acid for the treatment of postmenopausal osteoporosis.

Osteonecrosis Related to Once-Yearly Zoledronic Acid Treatment in an Osteoporotic Patient after Dental Implant

This paper presents a case of osteonecrosis of the jaw related to zoledronic acid (5 mg) administered once yearly to treat osteoporosis. A 79-year-old woman who has been treated for osteoporosis for 5 years with 5 applications of zoledronic acid was referred for evaluation. The patient had been submitted to dental implant placement and there was no osseointegration. On clinical examination, suppuration and exposed bone on the alveolar ridge were observed. Radiographic examination revealed an osteolytic area and bone sequestration. Both clinical and radiological features were suggestive of osteonecrosis. The treatment consisted of surgery to remove the affected bone completely. The patient is asymptomatic at 9 months after surgery. Dentists and oral surgeons should be alert to the possibility of osteonecrosis related to the use of once-yearly injections of zoledronic acid for the treatment of postmenopausal osteoporosis.

O presente estudo teve como objetivo apresentar um caso de osteonecrose dos maxilares associada ao uso de ácido zoledrônico (5 mg) administrado uma vez ao ano para tratar a osteoporose. Uma mulher de 79 anos de idade estava em tratamento de osteoporose por 5 anos com 5 aplicações do ácido zoledrônico foi encaminhada para nossa avaliação. A paciente tinha sido submetida à colocação de implante dental e não houve osseointegração. Ao exame clínico, supuração e osso exposto no rebordo alveolar foram observados. Os exames radiográficos revelaram uma área osteolítica e sequestro ósseo. Ambos os aspectos clínicos e radiográficos eram sugestivos de osteonecrose. O tratamento consistiu de cirurgia para remover todo o osso afetado. A paciente está assintomática há 9 meses (desde a cirurgia). Cirurgiões-dentistas e cirurgiões orais devem estar atentos para a possibilidade de osteonecrose relacionada ao uso de injeções anuais de ácido zoledrônico para tratamento da osteoporose pós-menopausa.

Syphilis related to atypical oral lesions affecting an elderly man. a case report.

OBJECTIVE: To present a case of oral syphilis in an old patient. BACKGROUND: Syphilis seems to be resurging mainly in the young. However, in the last twenty years, the elderly have become more susceptive to infectious diseases due to a more frequent use of sildenafil. CLINICAL REPORT: An 83-year-old man was referred to our clinic complaining of burning mouth. His medical history revealed papular lesions on chest and penis glans, which had been diagnosed and treated as scabiosis 2 months prior to our assessment. The intra-oral examination showed erosive and patch lesions on the bilateral lip commissures, the palate and the border of the tongue. Initially, oral herpes was suspected. However, both the serological test and the cytology were negative. Therefore, syphilis was hypothesised. Non-treponemic (VDRL) and treponemic tests (FTA-ABS) were reagent and secondary syphilis was confirmed. The treatment consisted of penicillin G benzathine 2.4 million IU/IM for 4 weeks. Both oral and skin lesions had complete remission. CONCLUSION: The present case illustrates that syphilis should be suspected in old patients with oral atypical lesions.

Estudo epidemiológico, clínico e imaginológico das lesões ósseas dos maxilares / Epidemiological, clinical and imaginologic study of bone lesions of the jaws

Introdução. O cirurgião-dentista é na maioria das vezes, o responsável pelo diagnóstico e tratamento das lesões ósseas dos maxilares. O diagnóstico é decisivo na conduta terapêutica a ser seguida. Na literatura, análises retrospectivas são vistas com maior frequência, onde foram coletados resultados de exames histopatológicos. Contudo, para algumas lesões, o diagnóstico é clínico e radiográfico, não sendo indicada a realização de biópsia. Objetivo. O objetivo deste estudo foi descrever a prevalência das lesões ósseas dos maxilares, assim como avaliar suas características clínicas e radiográficas. Correlacionar a principal hipótese diagnóstica com o diagnóstico final. Pacientes e Métodos. Estudo com 130 pacientes com lesões ósseas dos maxilares diagnosticadas no Centro de Diagnóstico Oral da Disciplina de Estomatologia Clínica da Faculdade de Odontologia da Universidade de São Paulo (CDO-FOUSP), entre Agosto de 2013 e Outubro de 2014. Os pacientes foram divididos em 4 grupos: 1: Tumores benignos odontogênicos e não odontogênicos. 2: Cistos odontogênicos e não odontogênicos. 3: Tumores malignos. 4: Outras lesões. Análise estatística foi realizada buscando estabelecer informações relevantes quanto aos dados epidemiológicos, clínicos e radiográficos destas lesões. Resultados. A idade média foi de 35,2 anos ±17,86, (variou entre 8 e 77 anos). Dos 130 pacientes, 71 eram mulheres (54,62%) e 87 leucodermas (66,92%). A mandíbula foi mais acometida (71,43%), do que a maxila (28,57%). As características clínicas mais observadas foram: aumento de volume em 60 casos (42,85%), dor em 38 (27,14%) e 16 casos (11,43%) apresentaram drenagem de secreção purulenta. O exame complementar de imagem mais utilizado foi a radiografia panorâmica, 124 exames (88,57%).

Em 47 lesões (33,57%), o diagnóstico foi realizado através do exame clínico, radiográfico e conduta cirúrgica (displasias ósseas, cistos ósseos simples, escleroses ósseas, dentre outras). Lesões com imagens radiolúcidas representaram 89 casos (63,57%), a forma unilocular esteve presente em 114 casos (81,43%) e 101 lesões (72,14%) apresentaram relação com o ápice dental. Dos casos que houve análise histopatológica (93 casos), o cisto periapical foi a lesão mais frequente totalizando 38 casos, 12 cistos dentígeros, 9 odontomas (7 compostos e 2 complexos), 8 TOQ, 6 cistos residuais, 5 ameloblastomas, e outras lesões. Houve 3 casos de tumores malignos, sendo 1 osteossarcoma, 1 carcinoma mucoepidermóide e 1 mieloma múltiplo. O percentual de acerto entre a principal hipótese diagnóstica com o diagnóstico final foi de 76,82%. Conclusões. Lesões ósseas foram frequentes e representaram aproximadamente 30% das primeiras consultas. Lesões com características radiográficas radiolúcidas e uniloculares foram as mais frequentes. Em um terço dos casos, não foi indicado (necessário) o exame histopatológico para a conclusão do diagnóstico. Sendo utilizadas as informações clínicas, radiográficas e abordagem cirúrgica (casos de cisto ósseo simples).

Introduction. The dentist is the main professional responsible for the diagnosis and treatment of bone lesions of the jaws. The diagnosis is crucial to therapeutic decision. In the literature, retrospective analyzes are more frequents, and the data are collected from histopathological exams. However, for some lesions, the diagnosis is clinical and radiographic, and the biopsy is not indicated. Objective. The aim of this study was to describe the prevalence of bone lesions of the jaws, and evaluate its clinical and radiographic features. In addition, the correlation between the main diagnosis and the final diagnosis was performed. Patients and Methods. A study which evaluated a total of 130 patients with bone lesions of the jaws. All cases were diagnosed in Oral Diagnosis Center of the Stomatology Discipline, School of Dentistry, University of São Paulo (CDO-FOUSP), between August 2013 and October 2014. Patients were divided into 4 groups: 1: Benign odontogenic and non odontogenic tumors. 2: Odontogenic and non odontogenic cysts. 3: Malignant tumors. 4: Other lesions. Statistical analysis was performed to establish relevant information on the epidemiological, clinical and radiographic data of these lesions. Results. The mean age of the patients was 35,2 years ± 17.86 (range, 8 to 77 years). Among 130 patients, 71 were women (54.62%) and 87 were Caucasians (66.92%).

The mandible was more affected (71.43%) than the maxilla (28.57%). The most frequent clinical signs were swelling in 60 cases (42.85%), pain in 38 (27.14%) and 16 cases (11.43%) showed purulent drainage. The panoramic radiograph was the most used imaging exam, 124 exams (88.57%). In 47 lesions (33.57%), the diagnosis was done by clinical examination, radiographic and surgical management (bone dysplasia, simple bone cysts, bone sclerosis, and others). Radiolucent lesions accounted for 89 cases (63.57%), the unilocular form was present in 114 cases (81.43%) and 101 lesions (72.14%) were related to the dental apex. A total of 93 cases had histopathological analyses; periapical cyst was the most frequent lesion, representing 38 cases, 12 dentigerous cysts, 9 odontomas (7 compounds and 2 complexes), 8 OKT, 6 residual cysts, 5 ameloblastomas and other lesions. There were 3 malignant tumors, 1 osteosarcoma, 1 mucoepidermoid carcinoma and 1 multiple myeloma. The correlation between the main diagnosis hypotheses with a final diagnosis showed a success rate of 76.82%. Conclusions. Bone lesions were frequent and represented approximately 30% of the first visit patients. Lesions that presented radiolucent and unilocular radiograph pattern were the most frequent. In one third of cases, it was not indicated (necessary) the histopathological examination to conclude the diagnosis. Being used data of clinical, radiographic and surgical approach (cases of simple bone cyst).

Malignant transformation of an odontogenic cyst in a period of 10 years.

Primary intraosseous carcinoma of the jaws (PIOSCC) might arise from odontogenic epithelium, more commonly from a previous odontogenic cyst. The aim of this case is to illustrate that the clinician should consider that an apparent benign dentigerous cyst can suffer malignant transformation and that all material removed from a patient must be evaluated histologically. A 44-year-old man presented in a routine periapical X-ray an impacted lower left third molar with radiolucency over its crown. Ten years later, the patient complained of pain in the same region and the tooth was extracted. After one month, the patient still complained of pain and suffered a fracture of the mandible. A biopsy was performed and carcinoma was diagnosed. The patient was treated surgically with adjuvant radio- and chemotherapy and after 8 years, he is well without signs of recurrences. This report describes a central mandibular carcinoma probably developed from a previous dentigerous cyst.