Animal Research in Pulp Biology: A Missing Link in the Translation of Regenerative Endodontics Innovations

Major advances in pulp biology, biomaterials, and tissue engineering have fuelled the development of regenerative strategies aimed at preserving or restoring pulp vitality. Despite this progress, the clinical translation of these discoveries remains limited or absent.

Although there is a global agenda to reduce and replace animal use in medical research, we believe that a critical missing link in the translational pipeline of regenerative endodontics innovations is the lack of rigorously validated, clinically relevant preclinical models to use in advancing promising in vitro findings through regulatory processes to human application.

While novel alternative methodologies (NAMs), including microfluidics, organoids, and organ-on-chip systems, offer human-relevant in vitro models and are rapidly transforming early-stage screening and mechanistic studies, they are currently insufficient to replicate the complex systemic elements provided by animal models, which are essential for demonstrating in vivo efficacy of regenerative therapies. Regulatory approval of devices, drugs, and biologics continues to require robust preclinical evidence generated in whole-organism systems, particularly when complex interactions involving immunity, vascularisation, innervation, and aging are central to therapeutic success.

In this perspective article, we discuss key scientific, methodological, and logistical considerations for the systematic development and validation of orthotopic animal models in regenerative endodontics research. We place particular emphasis on vital pulp treatment as a biologically and clinically relevant framework for studying pulp repair and in demonstrating the efficacy of novel therapies. We highlight the challenges that have hindered consensus in model selection and standardisation, and emphasise the need for coordinated transdisciplinary efforts to overcome these barriers.

We argue that prioritising standardised orthotopic vital pulp treatment models, in combination with evolving NAMs, represents a critical step to bridge the gap between mechanistic discoveries and clinical translation in regenerative endodontics.