The human body contains various types of cells, each with different functions to ensure a healthy life. Stem cells, which can transform into all cells within the organism and form the structure of all tissues and organs in the body, are defined as primary cells. These stem cells, which can renew and differentiate into specific cell types continuously, are present in every area of the body where needed. Due to their ability to transform and divide, stem cells play a crucial role in the regeneration of all tissues and organs that are diseased or damaged in the human body. Generally, there are two types of stem cells. One type is embryonic stem cells, whose acquisition and use involve legal and ethical issues. The other type is adult stem cells, including dental stem cells. Dental tissues are a rich source of mesenchymal stem cells (MSCs), adult stem cells found in connective tissue. Mesenchymal stem cells are of particular interest in cell-based therapies due to their characteristics and potential. With advances in technology and medical science, stem cell research in dentistry has become a promising field. This review provides an overview of MSC sources in dentistry.