Case Report Cholesterol Granuloma in the Maxillary Sinus: Are Endodontically Treated Teeth Involved in Its Etiopathogenesis? Silas Antonio Juvencio de Freitas Filho, 1 Gilberto Gallo Esteves, 2 and Denise Tostes Oliveira 1 1 Department of Surgery, Stomatology, Pathology and Radiology, Area of Pathology, Bauru School of Dentistry, University of S˜ ao Paulo, Bauru, SP, Brazil 2 Private Practice, Mar´ılia, SP, Brazil Correspondence should be addressed to Denise Tostes Oliveira; denisetostes@usp.br Received 9 August 2017; Accepted 19 September 2017; Published 19 October 2017 Academic Editor: Mark Li-Cheng Wu Copyright © 2017 Silas Antonio Juvencio de Freitas Filho et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Cholesterol granuloma (CG) is a tissue reaction in response to the accumulation of cholesterol crystals rarely found in the maxillary sinus. e etiopathogenesis of maxillary sinus CG remains unclear. We reviewed the literature and added two new reports of cholesterol granuloma in maxillary sinus related to endodontically treated maxillary posterior teeth. e first report refers to a 45-year-old woman diagnosed with rhinitis, who was submitted to endodontic retreatment of maxillary molar, and subsequently showed maxillary sinus opacity with cystic appearance. e second case describes a young adult woman, who presented a cystic mass in maxillary sinus aſter endodontic treatment, in close association with the apex of the maxillary right second premolar. Both patients were treated by a classic Caldwell-Luc surgery and the microscopic analyses revealed maxillary sinus CG. In the following, the authors discuss the probable involvement of endodontically treated maxillary posterior teeth in the etiopathogenesis of maxillary sinus CG. 1. Introduction Cholesterol granuloma (CG) is considered rare in maxillary sinus and approximately 50 cases were reported in English literature, with 12 of them being described from 2005 to 2016 [1–10]. e clinical features of CG in the maxillary sinus are nonspecific mimicking other cystic or inflammatory diseases [3]. It is oſten associated with a history of rhinitis, sinusitis, trauma, and paranasal sinus surgery [6, 9, 10] and can be accompanied by symptoms, such as facial pain, headache, otalgia, rhinorrhea, and nasal obstruction, commonly show- ing a cystic appearance and sinus opacification in radiological examinations [2, 3]. Diagnosis of maxillary sinus CG is based on microscopic analysis of a foreign body reaction characterized by foreign body giant cells and longitudinal cholesterol cleſts, granulo- cytes, foam cells, and macrophages filled with hemosiderin [2, 3]. Completing the findings, it is possible to observe fibrin deposition and local bleeding [3, 7]. Here we intend to report two cases of cholesterol granu- loma in the maxillary sinus and to discuss the involvement of endodontically treated maxillary posterior teeth in their probable pathogenesis. 2. Case Report 2.1. Case 1. A 45-year-old woman was attended in dental clinic, seeking oral rehabilitation. Clinical and radiographic examination revealed that the patient had undergone unsat- isfactory endodontic treatment in the maxillary right first primary molar and experienced painful symptomatology in this tooth which was then submitted to endodontic retreatment. Aſter this dental procedure, the patient reported pain, swelling, and nasal congestion, and a medication for rhinitis was prescribed. Radiographic evaluation revealed opacity and cystic appearance in the right maxillary sinus associated with the roots of the maxillary right first molar (Figure 1(a)). An excisional biopsy was performed in the Hindawi Case Reports in Pathology Volume 2017, Article ID 5249161, 5 pages https://doi.org/10.1155/2017/5249161