Made available in DSpace on 2014-12-17T15:32:29Z (GMT). No. of bitstreams: 1 KaruzaMAP_Tese.pdf: 829792 bytes, checksum: 60cd145c0f060b54f7dfbb5463648200 (MD5) Previous issue date: 2010-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Giant Cell Lesions, both the Central Giant Cells Lesions (CGCL) as the Peripheral Giant Cells Lesions (PGCL), correspond to a group of oral lesions that are histologically similar entities; however they show a variable clinical behaviour. The purpose of this study was to compare the immunohistochemical expression of bone resorption factors RANK (Receptor Activator of Nuclear Factor kappa B), RANKL (Receptor Activator of Nuclear Factor kappa B Ligand) and OPG (Osteoprotegerin) between CGCL and PGCL. Additionally, these bone resorption factors were examined in terms of aggressiveness of these lesions. The sample consisted of 61 cases, 30 cases of PGCL and 31 CGCL (16 non-aggressive and 15 aggressive). The analysis was performed by quantification of mononuclear cells (MO) and giant multinucleated cells (CG) immunopositive to anti-RANK, anti-RANKL and anti-OPG antibodies in 10 fields. Moreover, according to the proportion between the amount of cells positive for RANKL and OPG, the cases were categorized into: RANKL>OPG, OPG>RANKL e RANKL=OPG. CGCL showed a higher amount of MO (p=0.002) and total cells (p=0.003) both positives to RANKL compared with the PGCL. Additionally, the CGCL revealed a significant association with the ratio of RANKL>OPG (p=0.001). Analysis of the bone resorption factors revealed no significant differences between aggressive and non-aggressive CGCL (p>0.05). It was observed a positive correlation between the markers themselves, and a negative correlation between lesion size and quantity of OPG positive MO cells (p=0,004) and total cells (p=0,009). Through these results, we suggest that the greatest CGCL resorptive potential compared to the PGCL, may have occurred to the high expression of RANKL. Furthermore differences in the biological behavior of aggressive and non-aggressive CGCL appear to be related to the expression of these bone resorption factors / As Les?es de C?lulas Gigantes, tanto as Les?es Centrais (LCCG) quanto as Perif?ricas (LPCG), correspondem a um grupo de les?es orais que apresentam-se histologicamente semelhantes, por?m demonstram um comportamento cl?nico vari?vel. O prop?sito deste estudo foi comparar a express?o imuno-histoqu?mica dos fatores de reabsor??o ?ssea RANK (Receptor Ativador do Fator Nuclear kappa B), RANKL (Ligante do Receptor Ativador do Fator Nuclear kappa B) e OPG (Osteoprotegerina) entre LCCG e LPCG. Adicionalmente, esses fatores foram analisados nas LCCG quanto ? agressividade destas. A amostra consistiu de 61 casos, sendo 30 casos de LPCG e 31 de LCCG (16 n?o-agressivos e 15 agressivos). A an?lise foi realizada por meio da quantifica??o das c?lulas mononucleadas (MO) e c?lulas gigantes multinucleadas (CG) imunopositivas aos anticorpos anti-RANK, anti-RANKL e anti-OPG, em 10 campos. Al?m disso, de acordo com a propor??o entre quantidade total de c?lulas positivas para RANKL e para OPG, os casos foram categorizados em: RANKL>OPG, OPG>RANKL e RANKL=OPG. As LCCG apresentaram maior quantidade de MO (p=0,002) e c?lulas totais (p=0,003) positivas para RANKL, em compara??o com as LPCG. As LCCG ainda revelaram uma associa??o significativa com a propor??o de RANKL>OPG (p=0,001). A an?lise dos fatores de reabsor??o ?ssea n?o revelou diferen?as significativas entre LCCG agressivas e n?o-agressivas (p>0,05). Foi constatada correla??o positiva dos marcadores entre si, bem como uma correla??o negativa entre o tamanho das les?es e a quantidade de MO (p=0,004) e c?lulas totais (p=0,009) positivas para OPG. Diante desses resultados, concluise que o maior potencial reabsortivo das LCCG frente ?s LPCG pode ser decorrente da elevada express?o de RANKL. Al?m disso, as diferen?as nos comportamentos biol?gicos de LCCG agressivas e n?o-agressivas parecem n?o estar relacionadas com a express?o desses fatores de reabsor??o ?ssea.