Cellular Crosstalk Between Periodontal Ligament Fibroblasts and Macrophages: Insights from 2D and 3D Culture Systems in External Inflammatory Root Resorption.

INTRODUCTION: Root resorption following traumatic dental injuries is a complex process involving the breakdown of root dentin and cementum by odontoclasts, which differentiate from precursor macrophages. This differentiation is regulated by periodontal ligament fibroblasts (PDLF). Macrophages can polarize into two types: proinflammatory (M1) and anti-inflammatory (M2), which can influence either disease progression or healing.

METHODS: This review considers experimental models that have been utilized to study the interactions between PDLF and macrophages under normal and inflammatory conditions, including bacterial exposure and hypoxia.

RESULTS: Under normal circumstances, PDLFmaintain the balance of periodontal tissues and the surrounding immune environment. However, during inflammatory conditions such as exposure to bacteria or hypoxia, injured PDLF interact with macrophages through signaling mechanisms that promote the differentiation of macrophages into odontoclasts. Various experimental models have been utilized to study the interactions between PDLF and macrophages. These interactions alter the balance of macrophage polarization, with M1 macrophages contributing to disease progression.

CONCLUSION: This review highlights recent insights into the dynamic relationship between PDLF and macrophages in the context of external inflammatory root resorption, emphasizing the importance of their crosstalk in determining disease outcome.