Dento-Alveolar Infectious Diseases Among Hunter-Gatherers From Northeast and Central Chubut Province (Argentina) During the Late Holocene

Hunter-gatherers are often assumed to be less affected by dento-alveolar infections due to limited carbohydrate intake. Many studies, however, used outdated methods, suggesting that data from these societies need revision. This paper aims to assess whether late Holocene hunter-gatherers from Chubut Province (Argentina) exhibited a high frequency of caries and periapical lesions (PL) despite their reduced carbohydrate intake; explore whether different diets and environments between coastal and valley populations produced differences in oral infections; and investigate whether European contact negatively impacted oral health. The sample included 38 adults (638 teeth and 1031 alveoli). Caries and PL (granulomas, cysts, and chronic abscesses) were recorded and compared across sex, age, subregions (coast and valley), and temporal periods (precontact and postcontact). Dento-alveolar infections affected 71.1% of individuals (caries: 47.4%; PL: 36.8%) and correlated with dental wear and AMTL, suggesting underestimation of lesions. Caries were more frequent in young (60%) than in middle (52.6%) or old adults (22.2%), whereas PL mainly affected old (77.7%) compared to young (10%) and middle adults (31.6%). Caries were similar in both sexes (47.4%), whereas males had a higher frequency of PL (52.6%). No significant differences were found between coastal (caries 57.1%, PL: 38.1%) and valley populations (caries: 35.3%, PL: 35.3%). Periapical lesions were restricted to precontact period (61.1%), whereas caries were more frequent postcontact (66.7%). Hunter-gatherers from central Patagonia had a higher frequency of dento-alveolar infections than expected. Cysts were more common PL, likely due to lack of treatment before antibiotics. With respect to dietary groups, results suggest that environmental factors, cultural practices, or oral hygiene played a key role. A higher frequency of caries was recorded during postcontact, possibly linked to processed food consumption, whereas the abrasive precontact diet and higher dental wear may explain the increased PL frequency. This study enhances understanding of pathological diversity among past hunter-gatherers, considering diet, environment, and chronology. It also offers insights into the evolution of oral infectious diseases and their impact on human societies.