My research explores the intricate transcriptional regulatory forces that guide dental epithelial cells to commit to the ameloblast lineage—master architects of the hardest tissue in the human body. Once their enamel-secreting mission is complete, these cells undergo a remarkable transformation into junctional epithelial cells, forming a critical barrier that safeguards the health of the gingival sulcus. I also aim to clarify the roles of the junctional epithelium in innate immunity to effectively combat periodontal pathogens.