RANK/RANKL – OPG Pathway System
Poster Number
29
Introduction/Abstract
Orthodontic tooth movement is based on site-specific bone remodeling that is induced by therapeutic mechanical stresses applied to teeth. Bone resorption occurs on the compressed side, whereas bone formation occurs on the stretched side of the periodontal ligament space and alveolar bone.
Purpose
It is the aim of this literature review to give the reader an overview of cellular and molecular mechanisms involved in orthodontic tooth movement.
Method
Relevant recent articles were reviewed and the new information was combined with the previous knowledge.
Results
The mechanical force loaded onto a tooth affects the periodontal ligament first. The cells within the periodontal ligament respond to the mechanical stress by secretion of molecules that can induce resorption or formation of bone. Osteoclasts accumulate on the compressed side of an orthodontically moving tooth and resorb the alveolar bone. Receptor activator of nuclear factor kappa B (RANK) is a membrane bound protein, expressed on surface of cells belonging to the monocyte-macrophage lineage. Osteoclastogenesis is mainly regulated by two cytokines, receptor activator of nuclear factor kappa B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). RANKL is produced by osteoblasts. Binding of RANKL to RANK starts differentiation of monocytic progenitors into functional osteoclasts in the bone tissue. Osteoprotegerin (OPG) is a decoy receptor for RANKL. It is also secreted by osteoblasts and competes for RANKL. A proper balance between RANKL and OPG determines, if bone is resorbed or formed. Current exploration of this system has led to an increased understanding of a potential of various therapeutic modes. Locally administered bioactive molecules were shown to stimulate or inhibit tooth movement via manipulation of the RANK/RANKL- OPG pathway system. A potential of gene therapy targeting this system was studied in respect to improving results of bone grafting and of treatment of bone metabolic diseases, such as osteoporosis and arthritis. Finally, research on low-energy laser irradiation suggested that it may enhance velocity of tooth movement via induction of RANK and RANKL.
Significance
The knowledge of how the RANK/RANKL–OPG pathway system works can have a significant impact on current and future treatment modalities within the fields of dentistry, especially benefiting orthodontic patients.
Location
DeRosa University Center, Stockton campus, University of the Pacific
Format
Poster Presentation
RANK/RANKL – OPG Pathway System
DeRosa University Center, Stockton campus, University of the Pacific
Orthodontic tooth movement is based on site-specific bone remodeling that is induced by therapeutic mechanical stresses applied to teeth. Bone resorption occurs on the compressed side, whereas bone formation occurs on the stretched side of the periodontal ligament space and alveolar bone.