In this case series, radiographic images of healing lesions resulting from non-surgical root canal treatments and follow-up of periapical lesions caused by traumatic occlusion, untreated trauma injuries, inadequate root canal treatment, and pulp necrosis with deep caries and internal resorption are presented. The treatment of four cases consisting of mandibular and maxillary incisors, molars, and premolars with a lesion was completed by filling the root canals after opening the access cavity, applying bio-mechanical preparation, and canal medication with calcium hydroxide. The symptoms of the patients were evaluated with control examinations; lesion healing was followed by periapical radiographs taken from the patients. As a result of clinical and radiographic evaluations, it was observed that the lesions were greatly reduced, and bone formation occurred. Periapical lesions can be healed by performing conservative root canal treatment in line with correct procedures, even without surgical procedures.
Keywords: Calcium hydroxide, periapical lesion, root canal treatment, trauma.