OOOO ABSTRACTS

Volume 117, Number 2 Abstracts e147

PIDORODESKI NAGANO, ANDRÉ CAROLI ROCHA,SUZANA CANTANHEDE ORSINI MACHADO DE SOUSA,DÉCIO DOS SANTOS PINTO JÚNIOR. DENTALSCHOOL. UNIVERSITY OF SAO PAULO.

Osteosarcoma, a rare mesenchymal neoplasm, is character-ized by osteoid production by the neoplastic cells. Man, 30, had apainful swelling in the right posterior maxilla associated withmobility of teeth #17 and #18. Imaging showed bone rarefaction.An incisional biopsy was performed, and histopathological ex-amination revealed a proliferation of mesenchymal spindle-sha-ped cells in a loose stroma interspersed with irregular, immature,and basophilic cartilaginous tissue of variable chondrocyticmorphology, many of which were binucleate. At this time noosteoid tissue was found and S100 protein was diffusely positive.A provisional diagnosis of chondrosarcoma was rendered.However, after surgical excision, osteoid tissue was seen, leadingto a diagnosis of chondroblastic osteosarcoma. Differentiatingbetween chondrosarcoma and chondroblastic osteosarcoma inincisional biopsies may be difficult when the specimen is insuf-ficient, leading to further biopsy. Correct diagnosis is essential,since chondrosarcoma and osteosarcoma are treated differently.

PE-076 - CHONDROSARCOMA IN PAROTID GLAND:CASE REPORT. BÁRBARA VANESSA DE BRITOMONTEIRO, THÂMARA MANOELA MARINHO BEZERRA,JOABE DOS SANTOS PEREIRA, JOSÉ NAZARENOMOREIRA DE AGUIAR JÚNIOR, ASSIS FELIPEMEDEIROS ALBUQUERQUE, ADRIANO ROCHAGERMANO, MÁRCIA CRISTINA DA COSTA MIGUEL.FEDERAL UNIVERSITY OF RIO GRANDE DO NORTE.

Chondrosarcomas are uncommon malignant tumors in thehead and neck region, representing 0.1% of head and neck can-cers and 10% of all chondrosarcomas. Man, 53, had a tumor-likeswelling on the right preauricular region that had been presentfor10 years of evolution. Mild pain was elicited on palpation.Computed tomography revealed a tumor-like lesion near the pa-rotid gland and extending to the skull base. An incisional biopsywas performed. Histopathological evaluation found a prolifera-tion of malignant chondrocytes with intense nuclear and cellularpleomorfism, large hypercromatic nuclei, distinct nucleoli, andbinucleated cells arranged in lobules separated by thin septa ofconnective tissue. Furthermore, there was an intense deposition ofstrongly basophilic granular material of cartilage matrix separatedfrom the salivary glandular parenchyma. The preliminary hy-pothesis was salivary carcinosarcoma, but the definitive diagnosiswas chondrosarcoma. The patient was referred for surgicalresection and postoperative treatment.

PE-077 - CHRONIC OSTEOMYELITIS WITH PROLIFER-ATIVE PERIOSTITIS IN A CHILD: CASE REPORT. RAVENADE MORAES ALVES, MARIANA PAULA DE ARAÚJOMIRANDA, LUMA MACHADO DIAS, HANNAH MENEZESLIRA, FLÁVIA CALÓ AQUINO XAVIER, ANTÔNIOFERNANDO PEREIRA FALCÃO, PATRÍCIA LEITERIBEIRO LAMBERTI. UNIVERSIDADE FEDERAL DABAHIA.

Proliferative periostitis is a distinctive chronic osteomyelitischaracterized by an inflammatory process that lifts new bone offthe cortex. Girl, 12, had a progressive and painless facial asym-metry of 5-month’s duration. Clinical examination showed a hardswelling on the left side of the jaw, carious lesions in the firstmolar, and no general signs of inflammation. Periodontal

pathologies were not found. Plain radiographic findings showedfocal overgrowth of bone in the outer surface of the cortex,resulting in a laminated appearance resembling cortical onionskinning. The adjacent jawbone appeared normal. Based on theclinicoradiographic features, the diagnosis of chronic osteomye-litis with proliferative periostitis was established. Bone remod-eling after endodontic treatment without antibiotic therapy wasdetected by radiography after 2 years of follow-up. Since thedifferential diagnosis includes a variety of benign and malignantlesions, it is crucial to identify the true cause and treatment ofproliferative periostitis.

PE-078 - CLEIDOCRANIAL DYSPLASIA: CASE REPORTOF TWO SIBLINGS. LAIRA RENATA LEMOS SANTOS,SÍNTIQUE PRISCILA ALVES LUZ, PATRÍCIA LEITERIBEIRO LAMBERTI, JÉSSICA OLIVEIRA MELO DASILVA, ADRIANA BORGES OLIVEIRA, ANTÔNIO PEREIRAFALCÃO, VIVIANE ALMEIDA SARMENTO. UFBA.

Cleidocranial dysplasia (CCD) is a rare genetic congenitalautosomal dominant syndrome characterized by generalizedskeletal dysplasia. The objective of this study is to present a casereport of two siblings suffering from cleidocranial dysplasia. Bothpatients had clinical and radiographic features consistent with thedisease, such as hypoplasia of the clavicle, midface hypoplasia,narrow and deep palate, delayed eruption of permanent teeth, andthe presence of supernumerary teeth. There is a relative lack ofmedical complications in CCD in relation to other skeletal dys-plasias, and the dentist is often the first professional sought.Therefore dentists must have adequate knowledge of develop-mental disorders involving the maxillofacial structures becausethe earlier the diagnosis is made, the better will be the functionaladaptation of the individual and, consequently, its quality of life.

PE-079 - CLINICAL AND HISTOPATHOLOGICAL FEA-TURES OF JUVENILE OSSIFYNG FIBROMA: REPORT OFTHREE CASES. CAMILLA BORGES FERREIRA GOMES,FELIPE PAIVA FONSECA, PABLO AGUSTIN VARGAS,OSLEI PAES DE ALMEIDA, FLÁVIA SIROTHEAUCORRÊA PONTES, HÉLDER ANTÔNIO REBELOPONTES. FACULDADE DE ODONTOLOGIA DE PIRACI-CABA - FOP/UNICAMP.

Juvenile ossifying fibroma (JOF) is a controversial benigntumor that belongs to the group of fibro-osseous lesions from themaxillofacial region. JOF is considered a rare and uncommonbone-forming neoplasm with aggressive local growth recurrent,representing around 2% of the oral tumors in children andadolescence that have a preference for involving the maxilla.Symptoms can vary and include pain, swelling, nasal obstruction,and sinusitis. The World Health Organization proposed two his-topathological variations of conventional ossifying fibroma for thisbenign neoplasm: trabecular JOF and psammomatoid JOF. Thediagnosis of this lesion is based on a correlation of clinical, im-aging, and histopathological findings. We describe the clinico-pathological and radiographic features of three uncommon cases ofJOF in the mandible of female patients. Clinicians should be awareof this rare manifestation to make a correct diagnosis and excludemalignant lesions to ensure the right conservative treatment.

PE-080 - CLINICAL APPROACH TO OSSEOUS FLORIDDYSPLASIA IN A MEDICALLY COMPROMISEDPATIENT. MORGANA MARIA ROCHA PONTE,GLAUCIANY FONTELES VASCONCELOS, MANUELA