Background: Modern penitentiary systems attach great importance, at least in the area of formal and codified arrangements, to providing inmates with access to health care and rehabilitation. The aim of our study was to analyze the Web of Science (WoS) and SCOPUS medical databases in order to search for and evaluate the available literature discussing the oral status and dental treatment needs of adult male prisoners. Methods: The following terms were used: prisoners or inmates; oral health, oral status; periodontal status, periodontal disease; oral hygiene; caries; mucosa; and saliva. The studies were screened based on their title and abstract according to the PICO (population, intervention, control, and outcome) criteria. The research protocol was prepared on the basis of the 2020 PRISMA guidelines and was not registered. The available literature discussing the oral status and dental treatment needs of adult imprisoned patients was analyzed. The inclusion criteria were as follows: articles published in English between 1 January 2012 and 2022; articles discussing the oral cavity status of adult inmates over 18 years old (hard tissues, periodontal status, saliva, mucosa condition, or oral hygiene); articles with a full text available; and articles that were assessed as satisfactory according to the Newcastle–Ottawa Scale. Results: A total of 934 articles were identified, out of which 9 were included in the systematic review. Two articles discussed the oral condition of prisoners in Europe (Russia and Finland), four examined prisoners in Asia (three in India and one in Saudi Arabia), two examined prisoners in Africa (Nigeria), and one examined prisoners in the Americas (Brazil). Conclusions: The oral status of prisoners has been widely discussed in the available literature. Among inmates, a higher frequency of both caries and periodontal disease along with poorer oral hygiene were observed. It can be concluded that inmates should have access to specialized treatment from periodontists and endodontists.