All stages of Early Childhood Caries require treatment, including:
American Academy of Pediatric Dentistry. Policy on early childhood caries (ECC): Unique challenges and treatment options. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023: 92-3.
Weyant, Robert J. et al. Topical Fluoride For Caries Prevention. JADA, Nov 2013, Volume 144 (11): 1279–1291.