Dental calculus and dental pathologies of 40 adults from 4 archaeological sites from the coast and valley of northern Chile were studied: MO 1/6, PLM-4, AZ-8 and CAM-9, analyzing 10 individuals per site. In all of the dental calculus analyzed, phytolith and starches were found, except on the Late Archaic MO 1/6 site, which although did not present starch did present phytoliths. These results are consistent with the macroscopical observation, where individuals belonging to MO 1/6 site do not present dental cavities and generally have better dental health than those individuals from the Late Intermediate and Late Period, both valley and the coast associated with a mixed diet. Furthermore, a good concordance between grave goods plants and the identified varieties in the dental calculus was observed in individuals from Late Intermediate and Late period sites.