The aim of the study was to evaluate the presence and characteristics of dental modifications in pre-Columbian populations from three archaeological sites in the Costa Rican territory (Nacascolo, Jícaro and La Cascabel) in order to describe them according to previous classification. Specimens were obtained from the collections of  the National Museum of Costa Rica. All specimens were macroscopically analyzed and the pieces were classified. Photographic records were taken to each piece and a full description was done. Sixty one pieces with dental modifications were found. The types of dental modifications found were classified as A1, C2/C6, A2, C2, C1, E1 and A3 in order of prevalence. In conclusion, dental modifications were found in most of specimens. Particularly, C2/C6 modification was not reported by previous classifications.