Three types of human
odontogenic tumors histologically classified as compound composite
odontoma,
ossifying fibroma, and
Pindborg tumor were characterized using mid-infrared spectroscopy (mid-IR) and solid-state nuclear magnetic resonance (ssNMR). For comparison, human jawbone and dental mineralized tissues such as dentin, enamel, and
dental cement were also characterized. The studies focused on the structural properties and chemical composition of pathological tissues versus histochemically related tissues. All analyzed
tumors were composed of organic and
mineral parts and water.
Apatite was found to be the main constituent of the
mineral part. Various components (water, structural
hydroxyl groups,
carbonate ions (CO(3)(2-)), and
hydrogen phosphate ions (HPO(4)(2-))) and physicochemical parameters (index of
apatite maturity and crystallinity) were examined. The highest organic/
mineral ratio was observed in fibrocementoma, a finding that can be explained by the fibrous character of the
tumor. The lowest relative HPO(4)(2-) content was found in
odontoma. This
tumor is characterized by the highest
mineral crystallinity index and content of structural
hydroxyl groups. The
Pindborg tumor mineral portion was found to be poorly crystalline and rich in HPO(4)(2-). The relative CO(3)(2-) content was similar in all samples studied. The results of spectroscopic studies of
odontogenic tumors were consistent with the standard histochemical analysis. It was shown that the various techniques of ssNMR and elaborate analysis of the mid-IR spectra, applied together, provide valuable information about calcified benign
odontogenic tumors.