Regenerative Endodontic Therapy in Mature Teeth Using Human-Derived Composite Amnion-Chorion Membrane as a Bioactive Scaffold: A Pilot Animal Investigation

Abstract

Introduction: Human-derived composite amnion-chorion membrane (ACM) has been used for various regenerative treatments. The aim of this pilot study was to investigate the effectiveness of the ACM as a scaffold for pulp regeneration in mature canine teeth.

Methods: A total of 24 roots from mature premolars in dogs were included for regenerative procedures using blood clots (BC) (group 1, n = 8), collagen membrane (CM) (group 2, n = 8), and ACM (group 3, n = 8). Each tooth was left open through a buccal access to induce root canal infection and inflammation. The root canals were disinfected with 1.5% NaOCl and calcium hydroxide intracanal medicament. After 2 weeks, bleeding was evoked to induce blood clot formation (group 1) or before the placement of the membranes (groups 2 and 3). After 12 weeks, the animals were euthanized for histologic assessment. The histologic data including intracanal fibrous connective tissue, odontoblast-like cell lining, intracanal mineralized tissue, periapical inflammation, and apical closure were qualitatively and quantitively analyzed.

Results: Histologic analysis revealed that intracanal fibrous connective tissue was identified in all groups, but a higher volume of the fibrous tissues was formed in the ACM group. Odontoblast-like cells were only observed in the ACM group. The intracanal mineralized tissue was observed only in the BC and CM groups. The BC group showed more periapical inflammation than the ACM group (P < .05). Apical closure was more often found in the CM group than the BC group (P < .05).

Conclusions: More intracanal fibrous tissue and odontoblast-like cell lining, and less periapical inflammation were observed after regenerative endodontic treatment in mature teeth using the ACM than blood clot alone or blood clot with collagen membrane. The use of the ACM may be useful for a cell-homing-based pulp regeneration in mature teeth.

Keywords: Regenerative endodontic procedures; amnion-chorion membrane; mature teeth; pulp regeneration; scaffold.