Updated project metadata. Dental calculus is becoming a crucial material in the study of past populations, with increasing interest in its proteomic and genomic content. Here we suggest further development of protocol for analysis of ancient proteins and a combined approach for subsequent ancient DNA extraction. We tested the protocol on recent teeth. We then applied the optimised protocol to ancient teeth to limit the destruction of calculus, as it is a precious and irreplaceable source of dietary, microbiological, and ecological information in the archaeological context. Finally, the applicability of the protocol was proven on samples of ancient calculus.