RESUMEN
Background: As current ethical codes preclude determining whether the clinical improvements obtained with the use of three-dimensional (3D)-printed scaffolds represent true periodontal regeneration, the histological proof of evidence for regeneration must be demonstrated in animal models. Thus, this systematic review investigated the regenerative potential of 3D-printed scaffolds in animal models of periodontal defects. Materials and Methods: A systematic search was performed in four databases (Medline, Embase, Web of Science, and Scopus) to identify preclinical controlled studies that investigated the use of 3D-printed scaffolds for periodontal regeneration. Studies limited to periodontal defects treated with 3D scaffolds were eligible for inclusion. The primary outcome was periodontal regeneration, assessed histologically as new bone, cementum, and periodontal ligament (PDL). This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Quality was assessed according to the SRYCLE score. Results: Six studies met the inclusion criteria. Scaffolds were designed using computer-aided design software. While the absence of a scaffold resulted in defects repaired mainly with fibrous connective tissue, the use of nonguiding 3D scaffolds promoted some bone formation. Notably, the regeneration of cementum and functional PDL fibers perpendicularly inserted into the root surface and the alveolar bone was limited to the defects treated with multi-compartment fiber-guiding or ion-containing 3D scaffolds. Nevertheless, the quality of the evidence was limited due to the unclear risk of bias. Conclusions: Despite the limitations of the available evidence, the current data suggest that the use of printed multi-compartment fiber-guiding or ion-containing 3D scaffolds improves periodontal regeneration in animal models.