[Research progress in clinical prognosis of apical overfilling of root canal obturation]

Root canal obturation is conducted by using filling materials to tightly seal the root canal system after the procedure of preparation in order to control infection and promote periapical healing. The quality of root canal obturation is one of the essential factors affecting the prognosis of root canal treatment. Qualified root canal filling is defined as a homogeneous radiographic apical filling within the cemento-dentine junction with neither overfilling nor underfilling. This review elucidates the long-term outcome of root canal overfilling and its causes, the influence of apical overfilling on adjacent structures and the prevention and management of overfilling, so as to help the clinicians achieving a better outcome of root canal treatment and obtaining an optimal long-term prognosis.