Iatrogenic molar borings in 18th and early 19th century Native American dentitions.

Six iatrogenic dental borings were identified in four individuals of a Native American skeletal collection from an 18th and early 19th century Middle Columbia River burial site. The borings, all in maxillary first molars with severe dental attrition and secondary dentin, demonstrate striated walls and associated periapical alveolar lesions. An ethnographic review of the subsistence pattern during the burial period indicates a diet that is consistent in dental attrition with other riverine fisher-hunter-gathers. Histological changes of dental pulp tissue during the process of attrition may result in dental necrosis. Access into the pulp chamber is a technique used to drain necrotic fluid. A common Euro-American therapeutic dental practice of the 18th and 19th centuries for diseases of the pulp was dental extraction. Multiple dental borings indicate that the practice of molar drilling into the pulp chamber was an effective and independent technique used by the Wishram and Wasco people.