Social networks are colonised by a culture of confession that turns teenager privacy into a commodity to achieve recognition and social acceptance. This display accelerates the porosity of the boundaries between the public and the private and feeds surveillance capitalism. The aim of this systematic review is to examine the empirical evidence on the public-private interaction of teenagers' contributions to social networks in the last 5 years in databases: Eric, Scopus and Web of Science. Based on the Prisma Statement, the initial search produced 1449 documents, of which 81 were included in the final analysis after the application of exclusion and inclusion criteria and the purging of duplicates. The results show a field of study developed with a decreasing trend in production in recent years, knowledge gaps and discordant findings. It is concluded the need to build solid knowledge and initiate new lines in the study of the issue in order to understand the exhibition of teenagers in social networks. It is points out the urgency of a training based on their own media practices and in digital literacy for a broad understanding of online privacy.