Background In the contemporary era, where science and technology know no boundaries, this in vivo study explores the impact of growth modulation therapy using Twin Block, Forsus Fatigue Resistant, and Clear Block appliances on alkaline phosphatase (ALP) levels in gingival crevicular fluid (GCF). Bone physiology involves modeling and remodeling, with orthodontics applying forces to teeth, influencing tissue reactivity and bone modeling. ALP, a marker of osteoblast function, plays a crucial role in bone growth. GCF reflects immunological and inflammatory responses during orthodontic force application, making it a valuable medium for studying ongoing metabolic processes related to bone turnover. Aim The study aims to comparatively analyze ALP levels in GCF during growth modulation therapy, assessing the efficacy of Twin Block, Forsus Fatigue Resistant, and Clear Block appliances. The research involves 30 experimental samples divided into three study groups and a control group. The samples are collected at various time intervals, and ALP levels are analyzed using a spectrophotometer. Statistical analysis includes paired and unpaired t-tests, one-way analysis of variance (ANOVA), and multiple comparisons. Results Results demonstrate a significant increase in ALP levels during the growth modulation therapy, indicating a positive correlation with bone remodeling. Twin Block appears to be the most effective appliance, exhibiting higher ALP activity compared to Clear Block and Forsus groups. Conclusion In conclusion, this study provides valuable insights into the biochemical responses during growth modulation therapy, emphasizing the potential of GCF analysis in understanding orthodontic treatment effects.