Since prognostic indicators are likely to take on increasing importance as a diagnostic tool for selection of patients for implant provision, this study investigated the influence of the shape and resiliency of the mandibular alveolar ridge on the retention and stability of conventional complete dentures. Ninety- three edentulous patients wearing both maxillary and mandibular conventional complete dentures composed the sample. Data were collected regarding shape and resiliencyof the mandibular residual ridge. Dentures were assessed for retention and stability using an objective and reproducible tool.The associations between the clinical characteristics of the mandibular alveolar ridge and denture retention and stability were analyzed using chi-square and Fisher exact tests (a = 0.05). A significant association between ridge shape and denture stability (p < 0.05) was found, while ridge resiliency was significantly associated to denture retention (p < 0.001). Based on the results, mandibular ridge shape and resiliency influenced the retention and stability of conventional complete dentures.