The anthropologists and odontologists at the Central Identification Laboratory work with ancient remains, which often lack comprehensive antemortem records, have the potential for fragmentation and commingling, and have been subjected to environmental exposure. Such conditions make the use of traditional forensic identification techniques difficult or impossible. Teeth are thus a primary source for identification because they are highly resistant to environmental degradation and are an excellent source of mitochondrial DNA (mtDNA). The described technique is a method of sampling dentin that does not result in the total destruction of the tooth sample, while still providing sufficient material to obtain usable mtDNA sequences. The methods and materials of the technique are first described, followed by the presentation of a case study that involved its use. The case involved the recent application of the technique to the identification of remains believed from material evidence to be those of nine individuals in a U.S. aircraft lost on a combat mission in Laos in January 1968. All of the nine missing individuals were identified through various combinations of their biological profiles, mtDNA, and dental remains. Remains for two of them consisted only of a single disarticulated tooth for each individual. These limited dental remains were traced to the individuals by mtDNA testing. If a more destructive technique for sampling dentin had been used, there would have been no remains available for turnover and subsequent burial by the surviving family members. The advantages of horizontally sectioning a tooth include its simplicity, ease of access, preservation of crown and root structure, and the ability to restore the tooth close to its presampled state. If an additional DNA source is required, the root surface may be used for resampling. 5 figures and 4 references