The bioengineering aspect of this research originates from Wolff's law which explains bone adaptation due to mechanical loads at an organ-level. At a tissue- and a cell-level, local strains trigger mechanobiological events and are responsible for maintaining a uniform functional PDL-space. However, a uniform PDL-space can shift toward a nonuniform PDL-space due to aberrations in strains at the PDL-bone and PDL-cementum interfaces as a result of altered mechanobiology. We wil test cell- and tissue-level responses that could cause an increase or decrease in PDL-space and the accompanying gradients that result from a change in function. We will investigate:
Aim 1) that in situ the surfaces of bone and tooth are originally conforming and with application of mechanical load can induce localized compressive and tensile strains within the bone-tooth complex. Changes in PDL-space and resulting strains will be evaluated using a loading device coupled to a Micro X-ray computed tomography (?-XCT) followed by digital image correlation (DIC) of virtual sections taken at no load and loaded conditions;
Aim 2) that in vivo the mechanobiologically active compression and tension sites promote biochemical changes through expression of genes and matrix proteins, causing resorption and formation of bone and cementum resulting in a widened or a narrowed PDL-space. The spatiotemporal outcomes of mechanosensitive genes and protein expressions promoting mineral formation at the tension sites, resorption at the compression sites, and responsible for maintaining tissue and interface integrity will be mapped by using fluorescence based immunohistochemistry;
Aim 3) that biochemically altered regions identified in Aim 2 cause measurable changes in structure, chemical composition and mechanical properties of bone, cementum, PDL (e.g. tensile strains induce bone formation).
This aim i ncludes mapping the shifts in gradients of the PDL-bone and PDL-cementum interfaces. Spatiotemporal changes in local structure, chemical composition and mechanical properties of wet PDL-bone, PDL-cementum, cementum, bone, and PDL using state-of-the-art high resolution microscopy and spectroscopy equipment will be mapped;
Aim 4). the functionally adapted systems in situ have an altered response to mechanical loads. Load-displacement curves and correlating strains fields in adapted complexes of 2nd molar from freshly harvested experimental groups and controls (as in Aim 1) will be evaluated and compared. Studies will use in situ loading, ?-XCT, and DIC as in Aim 1.
The proposed translational research is based on our incomplete understanding of how PDL-space adapts to functional loads. Local functional adaptations can be unfavorable outcomes with an increased or a decreased range of tooth motion due to root and/or bone resorption or formation resulting in a widened (tooth loosening) or narrowed PDL-space (ankylosis). Such adapted sites could act as the local stress points inducing positive feedback when the complex is subjected to implants and/or periodontitis, normal or therapeutic loads (orthodontic braces) subsequently impairing function.
|Yang, Lynn; Kang, Misun; He, Rui et al. (2018) Microanatomical changes and biomolecular expression at the PDL-entheses during experimental tooth movement. J Periodontal Res :|
|Wiener, Scott V; Chen, Ling; Shimotake, Alex R et al. (2018) Novel insights into renal mineralization and stone formation through advanced imaging modalities. Connect Tissue Res 59:102-110|
|Wiener, Scott V; Ho, Sunita P; Stoller, Marshall L (2018) Beginnings of nephrolithiasis: insights into the past, present and future of Randall's plaque formation research. Curr Opin Nephrol Hypertens 27:236-242|
|Sherer, Benjamin A; Chen, Ling; Kang, Misun et al. (2018) A continuum of mineralization from human renal pyramid to stones on stems. Acta Biomater 71:72-85|
|Jang, A T; Chen, L; Shimotake, A R et al. (2018) A Force on the Crown and Tug of War in the Periodontal Complex. J Dent Res 97:241-250|
|Hsi, Ryan S; Ramaswamy, Krishna; Ho, Sunita P et al. (2017) The origins of urinary stone disease: upstream mineral formations initiate downstream Randall's plaque. BJU Int 119:177-184|
|Lin, Jeremy D; Jang, Andrew T; Kurylo, Michael P et al. (2017) Periodontal ligament entheses and their adaptive role in the context of dentoalveolar joint function. Dent Mater 33:650-666|
|Kurylo, Michael P; Grandfield, Kathryn; Marshall, Grayson W et al. (2016) Effect of proteoglycans at interfaces as related to location, architecture, and mechanical cues. Arch Oral Biol 63:82-92|
|Chien, Y-C; Burwell, A K; Saeki, K et al. (2016) Distinct decalcification process of dentin by different cariogenic organic acids: Kinetics, ultrastructure and mechanical properties. Arch Oral Biol 63:93-105|
|Cao, Zhengguo; Liu, Rubing; Zhang, Hua et al. (2015) Osterix controls cementoblast differentiation through downregulation of Wnt-signaling via enhancing DKK1 expression. Int J Biol Sci 11:335-44|
Showing the most recent 10 out of 28 publications