ovoid to round nuclei, immersed in a collagenous stroma. Between those granular cells, islands of odontogenic epithelium were present. In addition, cementum-like bodies and dystrophic calcification were seen, like in previous reports. 4,5,13,14 Immunohistochemical staining is a valuable tool in elucidating the possible origin and nature of the granular cells. 13 In the case reported, the vimentin positivity and S-100 protein and cytokeratin negativ- ity, by the granular cells, confirmed the mesenchymal origin while mitigating against epithelial or Schwann cell origin. Nevertheless, the literature reveals inconsistent findings regarding the expression of S-100 by the granular cells, with some authors reporting slight positivity. 15Y17 Yet, a histiocytic differentiation of the granular cells is proposed by the strong expression of the CD68, previously reported 4,5,7,12,18 and confirmed in the current case. However, it is suggested that the expression of CD68 by the tumor cells does not necessarily imply histiocytic origin because other studies have shown that CD68 is also expressed by nonYmacrophage-derived cells. 19,20 In addition, the epithelial islands had strong positive staining for CK14 and AE1/AE3, as previously reported. 5,7,18 Moreover, our study agrees with the hypothesis of mesenchymal origin owing to the in- tense immunoreactivity to CD68 and vimentin and absent immunos- taining for CK14 and AE1/AE3 by the granular cells. The first malignant case related by Piatelli et al 7 revealed similar immunohistochemical findings to the present case, suggesting that the distinction between a benign and a malignant lesion should be based on the clinical and histopathologic features. The treatment of GCOT consists of conservative surgical pro- cedures, most often enucleation or curettage. Clinical, radiographic, and the follow-up data led to the conclusion that this lesion has a benign biologic behavior. 5 However, long-term follow-up is recom- mended because a malignant counterpart of the CGCOT has already been reported, 7 and 1 case that was treated with curettage recurred 13 years after it was initially removed. 5 In conclusion, the immunohistochemical profile of CGCOT in this study and in other publications showed that the granular cells are mesenchymal in origin, with a possible histiocytic cell lineage. Yet, the present case shows a particular feature of large extension with perforation of the maxillary cortical plates, resembling a ma- lignancy, which was excluded according to microscopy findings. However, this feature highlights the possibility of aggressive be- havior by these lesions. In this sense, the clinical and imaging fea- tures of the lesion, associated to the histopathologic aspects, should be carefully evaluated to perform the correct diagnosis of CGCOT and exclude its various differential diagnoses. REFERENCES 1. Werthemann A. Uber spongiocytares adamantinoma [in German]. Oncologia 1950;3:193Y207 2. Couch RD, Morris EE, Vellios F. Granular cell ameloblastic fibroma. Report of 2 cases in adults, with observations of its similarity to congenital epulis. Am J Clin Pathol 1962;37:398Y404 3. Vincent SD, Hammond HL, Ellis GL, et al. Central granular cell odontogenic fibroma. Oral Surg Oral Med Oral Pathol 1987;63:715Y721 4. Gomes CC, NavesMD, Pereira MV, et al. Granular cell odontogenic tumour: case report and review of literature. Oral Oncol 2006;42:277Y280 5. Brannon RB, Goode RK, Eversole LR, et al. The central granular cell odontogenic tumor: report of 5 new cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:641Y621 6. Brannon RB. Central odontogenic fibroma, myxoma (odontogenic myxoma, fibromyxoma), and central odontogenic granular cell tumor. Oral Maxillofacial Surg Clin North Am 2004;16:359Y374 7. Piatelli A, Rubini C, Goteri G, et al. Central granular cell odontogenic tumour: report of the first malignant case and review of the literature. Oral Oncol 2003;39:78Y82 8. Martı ´nez-Mata G, Mosqueda-Taylor A, Carlos-Bregni R, et al. Odontogenic myxoma: clinico-pathological, immunohistochemical and ultrastructural findings of a multicentric series. Oral Oncol 2008;44:601Y607 9. Toro C, Millesi W, Zerman N, et al. A case of aggressive ossifying fibroma with massive involvement of the mandible: differential diagnosis and management options. Int J Pediatr Otorhinolaryngol Extra 2006;1:167Y172 10. Sopta J, Draºi( R, Tuli( G, et al. Cemento-ossifying fibroma of jawsVcorrelation of clinical and pathological findings. Clin Oral Investig 2011;15:201Y207 11. Lotay HS, Kalmar J, DeLeeuw K. Central odontogenic fibroma with features of central granular cell odontogenic tumor. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:63Y66 12. Calvo N, Alonso D, Prieto M, et al. Central odontogenic fibroma granular cell variant: a case report and review of literature. J Oral Maxillofac Surg 2002;60:1192Y1194 13. Yih WY, Thompson C, Meshul CK, et al. Central odontogenic granular cell tumor of the jaw: report of case and immunohistochemical and electron microscopy study. J Oral Maxillofac Surg 1995;53:453Y459 14. Gesek DJ Jr, Adrian JC, Reid EN. Central granular cell odontogenic tumor: a case report including light microscopy, immunohistochemistry, and literature review. J Oral Maxillofac Surg 1995;53:945Y949 15. Regezi JA, Kerr DA, Courtney RM. Odontogenic tumors: analysis of 706 cases. J Oral Surg 1978;36:771Y778 16. Shiro BC, Jacoway JR, Mirmiran SA, et al. Central odontogenic fibroma, granular cell variant. A case report with S-100 immunohistochemistry and a review of the literature. Oral Surg Oral Med Oral Pathol 1989;67:725Y730 17. Mirchandani R, Sciubba JJ, Mir R. Granular cell lesions of the jaws and oral cavity: a clinicopathologic, immunohistochemical, and ultrastructural study. J Oral Maxillofac Surg 1989;47:1248Y1255 18. de Sousa SO, de Arau´jo NS, Melhado RM, et al. Central odontogenic granular cell tumor: immunohistochemical study of two cases. J Oral Maxillofac Surg 1998;56:787Y791 19. Facchetti F, Bertalot G, Grigolato PG. KPl (CD68) staining of malignant melanomas. Histopathology 1991;19:141Y145 20. Doussis IA, Gatter KC, Mason DY. CD68 reactivity of nonmacrophage derived tumors in cytological specimens. J Clin Pathol 1993;46:334Y336 Foreign Body Ingestion During Dental Implant Procedures Thiago de Santana Santos, DDS, Msc,* Antonio Azoubel Antunes, DDS,* Andre´ Vajgel, DDS, Msc,Þ Thames Bruno Barbosa Cavalcanti, DDS,þ Luiz Ricardo Gomes de Caldas Nogueira, DDS,§ Jose´ Rodrigues Laureano Filho, DDS, Msc, PhDÞ From the *Oral and Maxillofacial Surgery Program, Faculdade de Odonto- logia de Ribeira˜o Preto, Universidade de Sa˜o Paulo, Sa˜o Paulo; †Oral and Maxillofacial Surgery Program, ‡Faculdade de Odontologia de Per- nambuco, Universidade de Pernambuco; and §Associa0a˜o Brasileira de Odontologia de Pernambuco, Pernambuco, Brazil. Received July 21, 2011. Accepted for publication October 9, 2011. Address correspondence and reprint requests to Thiago de Santana Santos, DDS, Msc, Faculdade de Odontologia de Pernambuco, Av General Newton Cavalcanti, 1650, 54.753-220. Camaragibe, Pernambuco, Brazil; E-mail: thiago.ctbmf@yahoo.com.br The authors report no conflicts of interest. Copyright * 2012 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0b013e31824cda32 The Journal of Craniofacial Surgery & Volume 23, Number 2, March 2012 Brief Clinical Studies * 2012 Mutaz B. Habal, MD e119 Copyright © 2012 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.