Relationship between autofluoresecence, elemental composition and mechanical properties
The regions of the teeth appearing green under CLSM (i.e., emitted a strong signal after excitement with the 488 nm laser) contained high proportions of Si and Ca. The sides of the stylus and the bases appeared red- to yellow-brown (i.e., emitted a strong signal after excitement with the lasers of 555 and 639 nm wavelength); here no high content of Ca and Si were detected. The bulges appeared blue (i.e., emitted a strong signal after excitement with the lasers of 405 nm wavelength); these regions contained no high content of the targeted elements and were the softest and most flexible tooth parts. We could not determine relationships between the elemental content of the inner tooth structure and the mechanical property values.