Background: The mucous membrane of the maxillary sinus is sensitivis susceptible to infection or inflammation adjacent to it, which may contribute to mucous membrane thickening (MMT). Residual alveolar bone quality (RABQ) is considered a quality of the remaining bone apical to periodontal defect adjoining to the floor of the maxillary sinus.
Objective: The current study aimed to analyze the minimum RABQ to prevent the extension of periodontal pathology from reaching maxillary sinus using cone-beam computed tomography (CBCT).