Background: A full understanding of the dental anatomy of permanent teeth is essential for all treatment aspects of these teeth. Knowledge of the normal and abnormal architecture of permanent teeth is necessary for making diagnosis and treatment decisions in patients. To examine the adverse effects of the Pfizer-BioNTech vaccine among adolescents aged 12-18 years in Saudi Arabia. The aim of this study was to do a systematic review of the literature on root morphology and root canal configuration in permanent mandibular dentition. Methods: Between September 2020 and October 2021. The PROSPERO database was used to record this systematic review, which followed the PRISMA criteria. To find and gather published literature on the anatomy of the root and root canal configuration of all permanent mandibular teeth in the Saudi population. Results: A search of electronic databases showed up 268 studies that were relevant. Seven more studies were included after cross-referencing. 246 of the 275 articles were deleted after a full-text analysis and duplication reduction. There were four prospective clinical trials, seven in vitro studies, and twenty-one in vivo investigations discovered. Conclusion: The data for this comprehensive analysis comes from 9682 mandibular teeth that were examined in various Saudi Arabian regions. The findings of this study’s Saudi population are equivalent to those of morphological research conducted across the world. Any morphological changes in the anterior teeth were quite uncommon. The number of roots and canals in some teeth, on the other hand, varied greatly.