ORIGINAL ARTICLE Oral Pathology Correlation between clinical and histopathological diagnoses in periapical inflammatory lesions Liliane Lopes Diegues 1 , Carlos Roberto Colombo Robazza 1 , Joa ˜ o Adolfo Costa Hanemann 1 , Alessandro Anto ˆ nio Costa Pereira 2 & Cle ´ verson O. Silva 3,4 1 Department of Clinic and Surgery, Alfenas Federal University, Alfenas, Brazil 2 Department of Biomedical Sciences, Alfenas Federal University, Alfenas, Brazil 3 Department of Dentistry, State University of Maringa ´ , Maringa ´ , Brazil 4 Department of Dentistry, Inga ´ University, Maringa ´ , Brazil Introduction Apical periodontitis consists of an inflammation and destruction of the tissues around the root of the teeth caused by etiological agents of endodontic origin. 1 It is usually a sequel of an endodontic infection that turns the dental pulp into a necrotic tissue infected by autogenous oral bacteria. This infection usually occurs through dental hard tissue damage resulting from caries, clinical proce- dures, or trauma, 2 and it provokes an inflammatory pro- cess that stimulates the proliferation of the cell rests of Malassez in the periodontal ligament. 1,2 The development of apical periodontitis can occur due to different mecha- nisms, such as accumulation of osmotic fluid in the lumen, proliferation of epithelial cell rests of Malassez, or molecular mechanisms. 3,4 Apical periodontitis is one of the most common patho- logical conditions within alveolar bone. As a result, clini- cians often make clinical and radiographic diagnoses, and the removed periapical tissues are seldom submitted for histopathological analysis, 5 which is in disagreement with the guidelines of the American Association of Endodon- tists. 6 Moreover, clinical and radiological evaluations alone cannot properly predict the type of lesion in the apical area, 7,8 and there are many studies suggesting that periapical biopsies result in contributory findings in 0.7–5% of cases. 9–11 The most common periapical lesions of endodontic origins are periapical abscess, periapical granuloma, and periapical cysts. However, there is extensive literature documenting periapical pathoses, with different treat- ment and prognostic implications considered clinically Keywords apical periodontal cyst, periapical cyst, periapical granuloma, periapical inflammatory lesion, radicular cyst. Correspondence Prof. Joa ˜ o Adolfo Costa Hanemann, Department of Clinic and Surgery, Alfenas Federal University, 700, Gabriel Monteiro da Silva Street, Alfenas 37130-000, MG, Brazil. Tel: +55-35-3299-1420 Email: jachanemann@uol.com.br Received 25 September 2010; accepted 25 December 2010. doi: 10.1111/j.2041-1626.2011.00053.x Abstract Aim: The purpose of the present study was to evaluate the correlation between clinical and histopathological diagnoses of periapical inflammatory lesions, focusing mainly on cystic conditions. Methods: Files dating from 1998 to 2006 at the Oral Pathology Laboratory, School of Dentistry, Alfenas Federal University, Brazil, were reviewed to iden- tify cases with histopathological diagnoses of periapical inflammatory lesions. A total of 1788 files were analyzed, and 255 cases were identified with clinical diagnoses of periapical inflammatory lesions. Results: The most prevalent clinical diagnosis was apical periodontal cyst (59%), followed by periapical granuloma (20%), and dentoalveolar abscess (2%). After histopathological analysis, 53% of the cases represented apical peri- odontal cyst, 42% periapical granuloma, and 5% dentoalveolar abscess. Conclusions: The outcomes of the present study show a high prevalence of periapical cysts among periapical inflammatory lesions. Moreover, this study highlights the importance of histopathological evaluation for the correct diag- nosis of periapical inflammatory lesions. Journal of Investigative and Clinical Dentistry (2011), 2, 184–186 184 ª 2011 Blackwell Publishing Asia Pty Ltd