PTH and dental fluorosis: Bone-specific alkaline phosphatase (BALP) is a stable indicator of osteoblast activity; Osteocalcin (OC) is involved in dentin formation and alveolar bone remodeling and has the highest contribution to the risk of dental fluorosis; Parathyroid hormone (PTH) regulates blood calcium concentration, participates in tooth development, and may be affected by fluoride exposure; Matrix metalloproteinase-2 (MMP-2) and MMP-9 play a key role in extracellular matrix degradation, promoting bone formation and participating in bone resorption and reconstruction, respectively.