The plastic nature of the human bone-periodontal ligament-tooth fibrous joint. Academic Article uri icon


  • This study investigates bony protrusions within a narrowed periodontal ligament space (PDL-space) of a human bone-PDL-tooth fibrous joint by mapping structural, biochemical, and mechanical heterogeneity. Higher resolution structural characterization was achieved via complementary atomic force microscopy (AFM), nano-transmission X-ray microscopy (nano-TXM), and microtomography (MicroXCT). Structural heterogeneity was correlated to biochemical and elemental composition, illustrated via histochemistry and microprobe X-ray fluorescence analysis (-XRF), and mechanical heterogeneity evaluated by AFM-based nanoindentation. Results demonstrated that the narrowed PDL-space was due to invasion of bundle bone (BB) into PDL-space. Protruded BB had a wider range with higher elastic modulus values (2-8GPa) compared to lamellar bone (0.8-6GPa), and increased quantities of Ca, P and Zn as revealed by -XRF. Interestingly, the hygroscopic 10-30m interface between protruded BB and lamellar bone exhibited higher X-ray attenuation similar to cement lines and lamellae within bone. Localization of the small leucine rich proteoglycan biglycan (BGN) responsible for mineralization was observed at the PDL-bone interface and around the osteocyte lacunae. Based on these results, it can be argued that the LB-BB interface was the original site of PDL attachment, and that the genesis of protruded BB identified as protrusions occurred as a result of shift in strain. We emphasize the importance of bony protrusions within the context of organ function and that additional study is warranted.

published proceedings

  • Bone

author list (cited authors)

  • Ho, S. P., Kurylo, M. P., Grandfield, K., Hurng, J., Herber, R., Ryder, M. I., ... Pianetta, P.

citation count

  • 26

complete list of authors

  • Ho, Sunita P||Kurylo, Michael P||Grandfield, Kathryn||Hurng, Jonathan||Herber, Ralf-Peter||Ryder, Mark I||Altoe, Virginia||Aloni, Shaul||Feng, Jian Q||Webb, Samuel||Marshall, Grayson W||Curtis, Donald||Andrews, Joy C||Pianetta, Piero

publication date

  • December 2013

published in