The purpose of this paper is to present the horizontal sectioning technique used by odontologists at the Central Identification Laboratory to sample dentin for mtDNA analysis. From the perspective of DNA testing, anthropologists and odontologists at the Central Identification Laboratory work with ancient remains. In many instances, the lack of comprehensive antemortem records, the potential for fragmentation and commingling, and environmental exposure makes the use of traditional forensic identification techniques difficult or impossible. Teeth are highly resistant to environmental degradation and are an excellent source of mitochondrial DNA (mtDNA). This technique is simple, quick, and relatively conservative, allowing for preservation of the majority of the external portion of the tooth structure.