Role of Masticatory Force in Modulating Jawbone Immunity and Bone Homeostasis: A Review

Abstract

Mastication exerts a significant influence on both the structural and immunological environment of the jawbone. The mechanical stress generated during chewing initiates bone remodeling through the coordinated activities of osteoclasts and osteoblasts, with these processes being modulated by immune cell responses. This review summarizes the interaction between masticatory forces and jawbone immunity, focusing on key mechanisms such as mechanotransduction in osteocytes, macrophage polarization, and the activation of T cells. The review also delves into the role of the receptor activator of nuclear factor κ-B ligand (RANKL), receptor activator of nuclear factor κ-B (RANK), and osteoprotegerin (OPG) signaling pathway, highlighting its critical function in bone resorption and immune regulation. Additionally, the review summarizes how masticatory forces modulate the immune response through changes in immune cells, particularly focusing on cytokines, and the involvement of hormonal and molecular pathways. These findings provide valuable insights into the complex interplay between mechanical forces and immune cells, with implications for bone health.

Keywords: jawbone immunity; masticatory force; mechanotransduction.

Figure 1

The mandibular immune system and bone cells exhibit a coordinated response under the impact of masticatory forces. Fibroblasts, osteoblasts, and osteocytes secrete IL-6, which leads to subsequent effects. Mechanical forces, such as pressure and stretching, regulate the transition between M1 and M2 macrophages, influencing angiogenesis and osteogenesis. T cells modulate osteoclast activity by regulating the secretion of Rankl. Additionally, the secretions of bone cells affect the differentiation of MSCs and the production of preosteoclasts. M1: M1 macrophages, M2: M2 macrophages, MSC: mesenchymal stem cell, HSC: hematopoietic stem cell.

Figure 2

Masticatory forces influence jawbone immunity and bone balance through other pathways. Masticatory forces can influence jawbone immunity and bone balance by (a) regulating hormone levels, (b) affecting non-coding RNA, and (c) modulating muscle-bone interaction.