Hello doctor, what is the earliest time at which healing can be seen on a radiograph?

A definite time cannot be given. Generally, we can say two to three months in children and six months in adults. Many factors affect this. It may vary with the position of the roots within the alveolar crest, whether the tooth is in the upper or lower jaw, bone density and lesion size. In some large lesions, healing may take up to four years.