C Degradation and Elimination of the Organic Component

The second major characteristic thermal phenomenon of bone tissue is associated with the degradation, combustion and elimination of the organic component. It is assumed 

The influence of the mineral phase on the thermal stability of the organic phase is confirmed by the comparative analysis of the demineralized bone and dried bone samples, in which a new endothermic process is found in the range 245-290 °C [37]. 

Moreover, the comparison of human bone tissue and a type I collagen reference material showed that the bone organic phase has a lower thermal stability with respect to pure collagen, which can be explained by the fact that the proteins denaturation leads to the formation of new bonds in the collagen (i.e. amorphous polymer formation). Within the osseous tissue these bonds occur at the interface between the organic and mineral components of bone, having a critical role in their interaction [9,40], 

In most of the studies performed on various bone tissues, the thermal event associated to collagen degradation is identified at a temperature situated between 250-500 °C, being strongly influenced by the analysis environment (e.g. decomposition is much faster in air) [6, 7, 13, 33,41]. 

Some variations of the organic component amount in the bone tissue of different species were identified [7, 13] dissimilar contents have been signaled also between the compact and cancellous bone tissue of the same species (a reduced organic phase is present in the cancellous bone) [30]. These variations are explained by the different reticular profiles adopted by each type of tissue. 

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