Fossil teeth are a primary source for inferring species development via evolutionary adaptation due to their linkage to feeding ecology and well perseverance. The main working tools in such studies are bite force analysis derived from jaw musculature and lever arms and morphogenetic based on enamel thickness and occlusal surface area. Despite progress made, quantitative correlation between predictions and behavior is still lacking. We studied histological sections in varieties of extracted premolar and molar human teeth. Sections corresponding to planes intersecting tips of primary cusps as well as more random planes were considered. The results revealed a unique, conclusive link between cuspal enamel thickness d_c and dentin horn angle φ, a developmental parameter which contribution to tooth functioning has been overlooked. Naturally led by design principles of corbel arches, we examined the bending stress at the horn apex due to axial cuspal loading. The results show that this d_c vs. φ relationship produces a constant force causing cusp fracture P_F, making the latter a viable measure of tooth resilience. A preliminary study on published sections of extinct hominin teeth showed that their d_c vs. φ behavior is consistent with modern humans albeit with varying P_F. Scaling BF with P_F enables direct estimate of bite force from measures of d_c and φ in fossil teeth, achievable nondestructively from micro-computed tomography scans.

Statement of Significance

The correspondence between cuspal enamel thickness and dentin horn angle in the postcanine is a natural design here revealed for the first time. This correspondence yields constant force causing fracture at the horn apex, P_F, making the latter a viable measure of tooth resilience. Scaling bite force (BF) with P_F enables direct estimate of BF. The proposed mechanistic link between bite force and anatomical parameters d_c and φ, expressed in a simple analytic form, offers direct, development-based expectation for examining evolutionary processes in hominins.

化石牙齿是通过进化适应来推断物种发育的主要来源，因为它们与进食生态和良好的毅力有联系。这些研究的主要工作工具是从下颌肌肉和杠杆臂得到的咬合力分析，并根据牙釉质厚度和咬合表​​面积进行形态发生分析。尽管取得了进展，但仍缺乏预测与行为之间的定量关联。我们研究了提取的前磨牙和磨牙人牙的组织学切片。考虑对应于与主尖的尖端相交的平面以及更多随机平面的截面。结果显示，骨牙釉质厚度d _c和牙本质角φ之间存在独特的结论性联系。，对牙齿功能有贡献的发育参数已被忽略。自然地以牛腿拱的设计原理为指导，我们研究了由于轴向骨载荷而在角顶点处产生的弯曲应力。结果表明，这种d _c与φ的关系会产生恒定的力，从而导致牙尖断裂P _F，从而使后者成为衡量牙齿弹性的可行方法。在绝种古人类牙齿的公布部分初步研究表明，他们d _Ç与φ的行为是与现代人类尽管有不同一致P _˚F。用P _F缩放BF可以根据化石牙齿中d _c和φ的测量值直接估算咬合力，这可以通过显微计算机断层扫描技术无损地实现。

重要声明

犬牙尖牙釉质厚度与牙本质角之间的对应关系是首次发现的自然设计。这种对应关系产生恒定的力，导致在角尖P _F处断裂，从而使后者成为牙齿弹性的可行度量。缩放咬力（BF）与P _˚F使BF的直接估计。咬合力与解剖参数d _c和φ之间的拟议机械联系以简单的分析形式表示，为检查人参的进化过程提供了直接的，基于发展的期望。