Krueger Kristin L, Towle Ian, Matthews Gregory J, Fernández Ana Álvarez, Hlusko Leslea J
Department of Anthropology, Loyola University Chicago, Chicago, Illinois, USA.
Centro Nacional de Investigación Sobre la Evolución Humana (CENIEH), Burgos, Spain.
Am J Biol Anthropol. 2025 Sep;188(1):e70126. doi: 10.1002/ajpa.70126.
This study evaluates molar wear progression in a captive baboon population under controlled dietary and environmental conditions. By comparing the dentin exposure ratio (DER) with a newly developed quadrant-based modification of Scott's dental wear scoring system (Krueger-Scott method), we evaluate how wear patterns vary by age, sex, and occlusal region.
Mandibular second molars (M) were assessed at two timepoints, during life and postmortem, in 201 captive baboons from the Southwest National Primate Research Center. Krueger-Scott and DER data were collected from 3D intraoral scans processed in MEDIT Link software. The Krueger-Scott scores assigned ordinal scores (1-10) to four equal quadrants of each M based on enamel facet development and dentin exposure. Statistical analyses tested relationships between wear progression, quadrant location, sex, and age.
Krueger-Scott scores and DER values increased significantly between timepoints, indicating wear progression. However, Krueger-Scott scores revealed strong functional patterning: buccal and lingual cusps showed high within-group correlations and weaker cross-group correlations. Males showed significantly higher wear than females, despite being younger on average. The relationship between age and wear progression differed by sex.
The Krueger-Scott method provided a more anatomically informative and efficient approach to tracking occlusal wear than DER. It captured regional wear variation and functional asymmetries that DER could not detect. Even under controlled conditions, sex-based differences in wear emerged, likely reflecting behavioral, morphological, or enamel structural variation. These findings offer a comparative baseline and demonstrate the utility of quadrant-level scoring for interpreting wear in extant and extinct taxa.
本研究评估在可控饮食和环境条件下圈养狒狒群体中磨牙磨损的进展情况。通过将牙本质暴露率（DER）与新开发的基于象限的斯科特牙齿磨损评分系统（克鲁格 - 斯科特方法）进行比较，我们评估磨损模式如何随年龄、性别和咬合区域而变化。
对来自西南国家灵长类动物研究中心的201只圈养狒狒的下颌第二磨牙（M）在生前和死后两个时间点进行评估。克鲁格 - 斯科特和DER数据从在MEDIT Link软件中处理的3D口腔内扫描中收集。克鲁格 - 斯科特评分根据牙釉质小面发育和牙本质暴露情况为每个M的四个相等象限分配序数分数（1 - 10）。统计分析测试了磨损进展、象限位置、性别和年龄之间的关系。
在两个时间点之间，克鲁格 - 斯科特评分和DER值显著增加，表明磨损在进展。然而，克鲁格 - 斯科特评分显示出强烈的功能模式：颊尖和舌尖在组内相关性高，而组间相关性较弱。尽管平均年龄较小，但雄性的磨损明显高于雌性。年龄与磨损进展之间的关系因性别而异。
与DER相比，克鲁格 - 斯科特方法为追踪咬合磨损提供了一种更具解剖学信息且更有效的方法。它捕捉到了DER无法检测到的区域磨损变化和功能不对称性。即使在可控条件下，磨损的性别差异也会出现，这可能反映了行为、形态或牙釉质结构的差异。这些发现提供了一个比较基线，并证明了象限水平评分在解释现存和已灭绝分类群磨损方面的实用性。
