RESUMEN
AIMS: To study the stromal variation and role of stromal-tumour cell interaction in impaired bone formation as well as enhanced bone resorption in ameloblastoma. METHODS AND RESULTS: Four types of stroma were observed histologically; fibrous, desmoplastic, myxoid and myxoid with hyalinization. Osteoblast and osteoclast were counted using haematoxylin and eosin sections and immunohistochemistry with CD68. After histomorphometric analysis, only fibrous and myxoid types of stroma were distinctly identified. Secreted frizzled-related peptide (sFRP)-2, transforming growth factor-beta 1 and receptor activator of nuclear factor-kappaB ligand (RANKL) revealed strong expression in myxoid type compared with the normal stroma. Bone morphogenetic protein (BMP)-2 was negative in myxoid type, but positive in normal stroma. Fibrous-type stroma showed weak expression of all antigens except RANKL compared with myxoid type. CONCLUSIONS: The results suggest that stroma does not act only in bone resorption, but also in the suppression of new bone formation. sFRP-2 is the main factor for impaired bone formation. The expression of markers related to osteoclastogenesis and suppression of osteoblast formation is higher in myxoid-type than in fibrous-type stroma. Tumour cells create a favourable environment for impaired bone formation by secreting sFRP-2 as well as bone resorption by secreting RANKL and interleukin-6.
Asunto(s)
Ameloblastoma/patología , Huesos/metabolismo , Neoplasias Maxilomandibulares/patología , Osteogénesis/fisiología , Células del Estroma/metabolismo , Adulto , Ameloblastoma/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Resorción Ósea/metabolismo , Resorción Ósea/patología , Huesos/patología , Femenino , Humanos , Interleucina-6/metabolismo , Neoplasias Maxilomandibulares/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patología , Ligando RANK/metabolismo , Células del Estroma/patología , Células Tumorales CultivadasRESUMEN
PURPOSE: This study evaluated a modified sagittal split ramus osteotomy designed to minimize displacement of the proximal segmentation asymmetric cases. PATIENTS AND METHODS: Nine patients with facial asymmetry were corrected with modified bilateral sagittal split ramus osteotomy from November 1992 to February 1999. Preoperative and 3-month postoperative anteroposterior (AP) radiographs were traced and compared. The angle of mandibular rotation of the proximal segments was obtained by measuring the intersection of lines passing through the upper rim of the orbit and the lateral border of the proximal segment. The condition of the temporomandibular joint (TMJ) was evaluated clinically by measuring the interincisal distance and looking for any untoward symptoms. RESULTS: The data showed an average 1.94 degrees +/- 1.18 degrees difference between the preoperative and postoperative condition and no clinical signs of TMJ symptoms. These findings support the use of this procedure for treating asymmetric mandibles.
