Structure and Composition of Abnormal Nodular Growth in Maxilla

Aim: The aim was to characterize the structure and composition of abnormal nodules observed in the maxilla of a 50year old male patient. He suffered severe jaw injuries when he was twenty. Methods: Tissue blocks containing these nodules were surgically removed and examined by histology, scanning electron microscopy (SEM), electron probe microanalysis (EPMA), and x-ray diffraction (XRD). Results: The calcific nodules, globular and less than 1 mm in diameter, were scattered in a noncalcified fibrous matrix. Each nodule consisted of a dense core firmly attached to the matrix through a less dense intermediate layer. The fiber strands radiated from this layer. The core exhibited a polyhedral grain structure.Each grain, ~ 1 micron, comprised of multitude of nanocrystals. Similar crystals were seen on fibers in proximity to the intermediate layer. The core and the intermediate layer were found to be rich in Ca and P. The XRD pattern of the core matched that of hydroxyapatite (HA) in dental enamel but with a higher degree of crystallinity. The intermediate layer was also found to be apatitic resembling the structure of dental cementum with lesser crystallinity. Conclusion: We suggest that the abnormal nodular maxillary growth studied is the result of trauma (stress) that induced localized calcification. The intermediate layer appears to be the advancing front of that mineralization process which began with the nucleation of HA within the extracellular fiber matrix.