title: Mechanoresponsive Properties of the Periodontal Ligament.
abstract: The periodontal ligament (PDL) functions as an enthesis, a connective tissue attachment that dissipates strains created by mechanical loading. Entheses are mechanoresponsive structures that rapidly adapt to changes in their mechanical loading; here we asked which features of the PDL are sensitive to such in vivo loading. We evaluated the PDL in 4 physiologically relevant mechanical environments, focusing on mitotic activity, cell density, collagen content, osteogenic protein expression, and organization of the tissue. In addition to examining PDLs that supported teeth under masticatory loading and eruptive forces, 2 additional mechanical conditions were created and analyzed: hypoloading and experimental tooth movement. Collectively, these data revealed that the adult PDL is a remarkably quiescent tissue and that only when it is subjected to increased loads--such as those associated with mastication, eruption, and orthodontic tooth movement-does the tissue increase its rate of cell proliferation and collagen production. These data have relevance in clinical scenarios where PDL acclimatization can be exploited to optimize tooth movement.
authors.affiliation: Orthodontic Department, Stomatology Hospital of Chongqing Medical University; Chongqing Key Laboratory of Oral Disease and Biomedical Sciences; Chongqing Municipal Key Laboratory, Chongqing, China Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: L
authors.initials: L
authors.lastname: Huang
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: J Y
authors.initials: JY
authors.lastname: Cha
authors.affiliation: Department of Orthodontics, Dalian Stomatological Hospital, Dalian Medical University, Dalian, China.
authors.forename: G
authors.initials: G
authors.lastname: Yuan
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: M
authors.initials: M
authors.lastname: Kelly
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: G
authors.initials: G
authors.lastname: Singh
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Hyman
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Brunski
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA jhelms@stanford.edu.
authors.forename: J A
authors.initials: JA
authors.lastname: Helms
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D003094:Collagen / Q000378:metabolism; D020342:Finite Element Analysis; D007150:Immunohistochemistry; D008409:Mastication / Q000502:physiology; D051379:Mice; D008855:Microscopy, Electron, Scanning; D008938:Mitosis / Q000502:physiology; D010513:Periodontal Ligament / Q000502:physiology*; D013314:Stress, Mechanical; D014078:Tooth Eruption / Q000502:physiology; D014087:Tooth Movement Techniques
chemical_list: D003094:Collagen
keywords: collagen; enthesis; mechanical; orthodontic; proliferation; tooth movement