Long-term follow-up of regenerative endodontic therapy in immature permanent molars: a report of three cases

Background: Regenerative endodontic therapy (RET) is a biologically based treatment for immature permanent teeth with necrotic pulp that promotes root development through intracanal disinfection and the use of calcium silicate-based materials; however, long-term clinical and radiographic data for immature permanent molars remain limited. The purpose of this case report was to present the long-term clinical and radiographic outcomes of RET in immature mandibular first molars and to assess its clinical applicability. Cases: RET was performed in three immature mandibular first molars of 9-year-old patients with follow-up periods ranging from 5 to 10 years. RET was applied under varying clinical conditions, including pulp necrosis and irreversible pulpitis, with treatment selection influenced by immature root morphology and patient cooperation. Throughout the follow-up period, all treated teeth remained asymptomatic and showed continued root development with apical closure. Root maturation progressed more slowly than expected, with apical closure occurring approximately two years later than the typical developmental timeframe. Conclusions: These case reports describe long-term clinical and radiographic outcomes following RET in immature mandibular first molars. In our cases, root maturation and apical closure occurred later than expected in all treated teeth. However, this gradual development was not associated with adverse clinical findings during follow-up. Although limited by the small number of cases, these observations may support the possibility that RET is a viable treatment approach for some immature permanent molars.

Regenerative endodontic therapy; Immature permanent molars; Apical closure

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