Apexification: Review of the Literature

Author(s): Morse, D et al.
Journal: Quintessence International
Volume (number): 21:7
Month, Year: 1990, 593-597
Major topic: to review methods of apexification
Minor topic(s): to explore possible mechanisms of how apical closure occurs with apexification via Ca(OH)2
Type of Article: literature review
Main Purpose(s): to review 5 methods of apexification
Overview of method of research: Five methods of apexification were reviewed: 1) fill the root canal with the blunt end of the gutta-percha cone and sealer 2) fill the canal well short of the apex with gutta-percha & sealer or ZOE alone 3)filling the canal with gutta-percha and sealer as well as possible and then performing periapical surgery with or without reverse seal 4)forming an apical stop with Ca(OH)2 and then filling with gutta-percha and sealer 5) “one visit apexification”: placing tricalcium phosphate or dentinal chips in the apical portion of the canal to form an apical barrier and then filling with gutta-percha and sealer
Findings: The authors discourage against the first approach of apexification, stating it makes it difficult to assess root development; The authors also discourage against the second approach, stating it allows for remaining microbes in the apical portion of the canal; The third approach, (periapical surgery) is endorsed for cases in which a more conservative approach can not be done, since there is evidence of its clinical success; however, it is also discouraged by clinicians who argue that periapical surgery further reduces the crown-root ratio, it may be difficult for a young patient to experience and cooperate with, the apical walls could be fractured by the hall drill, the periapical tissue may not acclimate to the amalgam (retrograde seal), and the thin apical walls could make condensation difficult and thus create an inadequate seal. The authors found that the most widely used approach to treating these nonvital immature permanent teeth was apical closure induction. The aim of this approach is to stimulate and preserve the formative activity of the granulation tissue cells in the apical portion of the canal, which should then enhance formation of a calcification. There is debate as to whether stimulating the periapical tissues to create a blood clot helps or hurts apexification via apical closure. Ca(OH)2 has been successful in inducing apical closure, when mixed with a variety of other substances such as sterile saline, anesthetic solutions without a vasoconstrictor, methylcellulose, and idodoform. The authors discourage using ‘one-visit apexification’ on excessively short roots as it does not allow for continued root development, but merely creates a stop.
Key points/Summary: Apexification is defined as the formation of mineralized tissue in the apical pulp area of a non-vital tooth with an open apex. The apical closure is usually irregular in form, and often results in irregular root development. This is different from apexogenesis, which is done on a vital tooth and results in regular apical closure and normal-appearing root development. Ca(OH)2 is bactericidal and antiseptic, in vitro. Ca(OH)2 accelerates hard tissue bridging at the apex irrespective of the initially induced inflammatory state. The success of Ca(OH)2 during apexification is attributed to the pH, the calcium ion, the hydroxyl ion, and the antibacterial effect.
Assessment of article: good review