Purpose: The aim of this study was to compare the percentage of tissue types and assess the presence/absence of odontoblasts or preodontoblasts in granulation tissue harvested from lesions associated with teeth extracted due to endodontic and periodontal reasons. Materials and Methods: Histologic reports of cases with a confirmed diagnosis (ie, endodontic or periodontal diseases) were included. These should include a semiquantitative analysis of the percentage of tissue types per sample (ie, epithelium, subepithelial connective tissue, bone or chronic inflammation/ deep connective tissue). The overall percentage of tissue type per diagnosis was calculated. Quantitative variables were summarized with means and standard deviations. Normal distribution was tested by the D'Agostino-Pearson omnibus normality test. The level of P .05 was adopted for statistical significance. Finally, an analysis of the salient findings was summarized. Results: The reports from 19 patients were included, 9 of endodontic and 10 of periodontal origins. The granulomatous tissue of endodontic and periodontal disease origin was similar, and consisted mainly of chronic inflammation (endodontic 40%, periodontal 41.7%), followed by epithelium (endodontic 25.7%, periodontal 29.2%), subepithelial connective tissue (endodontic 18.6%, periodontal 20.8%), and bone (endodontic 15.7%, periodontal 8.3%). No significant differences were found when comparing the groups regarding the percentage of tissue types (P ≥ .05). No osteoblasts or preosteoblasts were reported. Conclusion: Within the limitations of the study, the granulomatous tissues associated with chronic infection of endodontic or periodontal origin are comparable and consist primarily of chronic inflammatory cells. Keywords: granuloma, healing, histology, osteoblasts, periapical periodontitis, periodontitis