Core Matrisome Protein Signature During Periodontal Ligament Maturation From Pre-occlusal Eruption to Occlusal Function

Abstract

The pre-occlusal eruption brings the molars into functional occlusion and initiates tensional strains during mastication. We hypothesized that upon establishment of occlusal contact, the periodontal ligament (PDL) undergoes cell and extracellular matrix maturation to adapt to this mechanical function. The PDL of 12 Wistar male rats were laser microdissected to observe the proteomic changes between stages of preocclusal eruption, initial occlusal contact and 1-week after occlusion. The proteome was screened by mass spectrometry and confirmed by immunofluorescence. The PDL underwent maturation upon establishment of occlusion. Downregulation of alphafetoprotein stem cell marker and protein synthesis markers indicate cell differentiation. Upregulated proteins were components of the extracellular matrix (ECM) and were characterized with the matrisome project database. In particular, periostin, a major protein of the PDL, was induced following occlusal contact and localized around collagen α-1 (III) bundles. This co-localization coincided with organization of collagen fibers in direction of the occlusal forces. Establishment of occlusion coincides with cellular differentiation and the maturation of the PDL. Co-localization of periostin and collagen with subsequent fiber organization may help counteract tensional forces and reinforce the ECM structure. This may be a key mechanism of the PDL to adapt to occlusal forces and maintain structural integrity.

Nonuniformity in Periodontal Ligament: Mechanics and Matrix Composition

“…It is also associated with anchoring the basement membrane of blood vessels, nerves, and muscles to the ECM (Timpl and Chu 1994). A recent study found higher abundance for collagen VI in the cervical region of the PDL relative to more apical regions of the PDL, which further supports our findings (Denes et al 2020). The authors also found a high abundance of type XII collagen in the collar, similar to our nontargeted proteomics results.…”

Extracellular Matrix Derived From Dental Pulp Stem Cells Promotes Mineralization

“…On the other hand, 146 proteins were found in matrisome proteins of ECM derived from dentin and detected collagens, glycoprotein, affiliated proteins, regulator proteins, secreted protein, and proteoglycans, respectively (Reis et al, 2020). ECM of periodontal ligament (another oral tissue) is composed of 105 matrisome proteins, and highest detection was of regulator proteins, then glycoproteins, collagens, affiliated proteins, proteoglycans, and secreted proteins, respectively (Denes et al, 2020). Therefore, differences among ECM proteins in each matrisome component might be specific of a type of tissue and might lead to specific regulation and function from ECM proteins.…”

Decoronation - a treatment option of an ankylosed permanent tooth in children and adolescents

“…Normally during the growth of children, the forces of periodontal and gingival fibers allow bone apposition on top of the interdental septum [6]. In the area of an ankylosed tooth, with partly or completely resorbed periodontal fibers, the marginal bone development terminates and the tooth eruption arrests.…”