Apexification is a method of dental treatment to induce a calcific barrier in a root with incomplete formation or open apex of a tooth with necrotic pulp. Pulpal involvement usually occurs as a consequence of trauma or caries involvement of young or immature permanent teeth. As a sequelae of untreated pulp involvement, loss of pulp vitality or necrotic pulp took place for the involved teeth.

The main purpose of apexification includes restoring the original physiologic structures and functions of the pulp-dentin complex of the teeth. In addition to that, the elimination of the pulp tissue within a tooth, the disinfection of root canal system by using irrigants such as sodium hypochlorite and ethylenediaminetetraacetic acid are the necessary steps to ensure that the purpose of apexification is being met.

The apexification procedure will normally requires several monthly appointments or follow-ups to observe any calcific changes induced at the apex of tooth concerned. In these visits, a material known as calcium hydroxide ( Ca(OH)₂ ) will be placed inside the root canal systems to eliminate intracanal infection, stimulates calcification and achieves apical barrier seal at the apex of tooth root. The success rate of applying the traditionally used calcium hydroxide to induce calcific barrier is between 74%-100%. Nowadays, a newer material known as  mineral trioxide aggregate (MTA) is widely used as well.

Some difficulties are said to be a major clinical challenge when carrying out apexification, including difficulty in achieving appropriate apical seal with an open apex. Besides that, the termination of development of dentinal walls after pulpal pathologies occur will result in roots with thin dentinal wall and thus, producing a higher risk of tooth fracture.

Apexification is indicated for immature permanent teeth that are non-vital with incompletely formed roots. The objective of this procedure is to induce root end closure (apexification) at the apices of immature roots through the formation of mineralized tissue. Apical closure can take various forms but in most cases, it appears to be irregular and aberrant. Along with apical closure, root development may or may not continue.

There are different materials to be used in apexification such as Mineral trioxide aggregate (MTA), Bioceramics and Biodentine.

Mineral trioxide aggregate (MTA) is composed primarily of tricalcium silicate, tricalcium aluminate, tricalcium oxide, and silicate oxide. It has been used in endodontics as a root-end filling material, and sets in the presence of moisture. It presents in either grey or white form, the difference between the two being that white MTA lacks iron.

After numerous testing and analysis, MTA showed superior properties from its physical properties and biocompatibility. It is shown to have less marginal gap formation, less leakage  and better adaptation than other filling materials. Besides, root ends filled with MTA showed good healing with absence of periradicular inflammation over the root-end filling material, as compared to amalgam. The use of MTA as endodontic repair material stimulates bone formation as well as inhibits bone resorption.