Lack of periradicular healing and gradually increasing swelling two years after intentional extrusion of calcium hydroxide into periapical lesion: report of a case Konstantinos Ioannidis, DDS, a Vasilios Thomaidis, DDS, MD, PhD, b Aliki Fiska, MD, PhD, b and Theodore Lambrianidis, DDS, PhD, a Thessaloniki and Alexandroupoli, Greece ARISTOTLE UNIVERSITY OF THESSALONIKI AND DEMOCRITUS UNIVERSITY OF THRACE A 40-year-old female patient with noncontributory medical history presented to the postgraduate clinic of the Department of Endodontology, Aristotle University of Thessaloniki, Greece. Her chief complaint was a gradually increasing swelling in the left side of her maxilla, during the preceding 2 months. After clinical examination, the radiologic and computerized tomographic scan examinations revealed the presence of a radiopaque foreign material in contact with the apex of tooth #22, confined within the limits of a radiolucent area. On dental anamnesis and after communication with her dentist, it was concluded that calcium hydroxide was deliberately extruded for the healing of the large lesion. The patient was scheduled for periapical surgery. The histopathologic features of the lesion revealed the presence of a periapical cyst and the absence of foreign body giant cells. After an observation period of 1 year, healing was uneventful. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e86-e91) Calcium hydroxide has been used in dentistry for al- most a century. 1 In endodontics, the application of calcium hydroxide as an interappointment intracanal medicament has become a common therapeutic mea- sure for the elimination of remaining bacteria after chemomechanical preparation 2,3 and the promotion of healing of apical periodontitis. 4,5 The bactericidal ef- fect of calcium hydroxide is attributed to its high alka- linity; however, the overall mechanism of this action is not yet fully understood. 6 The deliberate extrusion of calcium hydroxide in the periradicular tissues, in cases of large lesions or peria- pical cysts, has been advocated in the literature. 7 At the same time, it has been shown by several studies that any extrusion of intracanal medicaments in the perira- dicular tissues or anatomic regions during root canal treatment may cause adverse reactions. Gingiva and mucosa necrosis have been reported when a surplus amount of calcium hydroxide was dis- placed through a buccal root perforation 8 and through a severe external root resorption of the cervical and mid- dle third. 9 Facial ischemia that led to scalp, skin, and mucosa necrosis were described when it was extruded within the mandibular canal 10 or the greater palatine artery. 11 Experimental studies have shown that the exposure of nerve tissue in direct contact with calcium hydrox- ide, for 1 hour, causes irreversible damage leading to reduced nerve activity. 12-14 Several case reports showed that direct contact of the calcium hydroxide with neurovascular bundles induced hypesthesia and paresthesia of the inferior alveolar, trigeminal, and in- fraorbital nerves. 10,11,15-17 In the current literature, there is 1 available experi- mental study that evaluated the effect of injected cal- cium hydroxide into the maxillary sinus cavity of monkeys. 18 Sinusitis was described as the initial in- flammatory response of the sinus mucosa, but later the calcified mass acted as a foreign body. 18 There are few reports that describe the accidental displacement of calcium hydroxide into the maxillary sinus, with favor- able healing process that did not require surgical inter- vention. 19-22 In the present case report, a gradually increasing, symptomatic swelling during a 2-month period result- ing from intentional extrusion of calcium hydroxide, during root canal treatment performed 2 years before, is presented. CASE REPORT A 40-year-old female patient presented to the postgraduate clinic of the Department of Endodontology, Aristotle Univer- sity of Thessaloniki, Greece, complaining about the presence of a gradually increasing swelling in the left side of her maxilla, during the preceding 2 months. The patient’s medical history was noncontributory. a Department of Endodontology, School of Dentistry, Aristotle Uni- versity of Thessaloniki. b Department of Anatomy, Medical School, Democritus University of Thrace. Received for publication Jan 25, 2010; returned for revision Feb 2, 2010; accepted for publication Feb 5, 2010. 1079-2104/$ - see front matter © 2010 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2010.02.006 e86