Teeth where the original diagnosis has been sterile necrosis, e.g. after trauma, are controlled usually 3 and 6 months after root filling, depending on the type and time of the trauma. The prognosis of the treatment of sterile necrosis is equally good as in pulpitis, between 85 and 95 %. Absence of microbes in the root canal when the treatment is started is a major factor for good prognosis.