Overview
Dental fluorosis is a developmental defect of enamel caused by excessive systemic fluoride ingestion during the critical period of tooth development — primarily from birth to age 8 for permanent teeth.
Fluoride inhibits the proteolytic enzymes (matrix metalloproteinases and kallikrein-4) responsible for removing enamel matrix proteins during the maturation stage of amelogenesis, resulting in retention of protein and hypomineralization.
The condition spans from barely detectable white lines on enamel to severe pitting, brown staining, and significant aesthetic compromise, depending on the degree and timing of fluoride exposure.