Dentigerous cysts may be of developmental or inflammatory origin. The latter occur in unerupted permanent teeth as a result of inflammation from a preceding non-vital primary tooth or from another source spreading to involve the tooth follicle. This report presents two clinical cases of children with dentigerous cysts of inflammatory origin. Case 1 is a healthy boy (7 years 11 months) referred for a large cystic cavity in the right mandibular premolar region. Extraction of 84 and 85 and marsupialization of the cyst were performed under nitrous sedation. A removable appliance with an acrylic piece fitted into the socket was applied on the same occasion. The in-socket piece was progressively reduced as the cystic cavity was shrinking. After a 20-month follow-up, 44 and 45 are sound and correctly erupted and 46 remains unaffected. Case 2 is an autistic girl (10 years 9 months) with bilateral large odontogenic cysts enclosing the crowns of 35 and 45. Extractions of 75, 85 were performed under general anesthesia, leaving large bone defects. Given the limited compliance of the patient under common dental office circumstances, no appliance was used. Thirteen months after extraction, 35 and 45 are sound, fully erupted and no visible mesial drifting of 36 and 46 occurred. In conclusion, conservative treatment of large inflammatory dentigerous cysts in children gives good results with minimal intervention, ensures physiologic development of teeth and proper bone healing. The general condition of the patient can influence treatment choice. Patients must be followed up until eruption of the displaced permanent teeth and bony consolidation of the cyst.