Regenerative Dentistry: Animal Model for Regenerative Endodontology

Abstract

Background: Ectopic tissue has been observed frequently in human root canal specimens when cell homing studies were performed at the dorsum of rodents. In contrast, pulp-like tissue formed when immature teeth were implanted on top of the rat calvaria. It was surmised, yet not tested, that the implantation site might affect tissue ingrowth. Methods: Four root sections from human immature molars cleaned with 5% sodium hypochlorite (NaOCl) followed by 17% ethylenediaminetetraacetic acid (EDTA) were implanted per rat (n = 5). Two specimens were placed at the dorsum (control), while the other two specimens were implanted at the calvaria. After 6 weeks, the specimens were investigated for histological structure, immunoreactivity to dentine sialoprotein (DSP) and bone sialoprotein (BSP), per-area percentage of tissue ingrowth, and gene expression (DSPP, COL1, NGF and VEGF). Data were statistically compared. Results: Tooth specimens placed at the calvaria generally showed pulp-like tissue and odontoblast-like cells at the dentinal wall where DSP and BSP immunoreactivity were intense. The area of tissue ingrowth was significantly larger in the specimens placed at the calvaria compared to those placed at the dorsum. DSPP was the only gene that was upregulated significantly when specimens were implanted at the calvaria. Conclusion: Our findings suggest that the calvarial site is superior to the dorsum to study pulp regeneration in human teeth in the rat.

Dental pulp regeneration via cell homing

“…Unlike previous studies, Ruangsawasdi et al . () investigated the effects of the implantation site in an animal model for pulp regeneration. Pulp‐like tissue formation in teeth placed at the calvaria of rats was compared to that obtained at the dorsal area.…”

Cytokine expression in response to root repair agents

“…Animal models, and more specifically rodent models, have been used extensively and have contributed greatly to the development and establishment of a wide range of translational approaches aiming to regenerate bone tissue. In this regard, the calvarial model has found great application in basic and applied research (Gomes & Fernandes 2011, Alquhali et al 2015, Ruangsawasdi et al 2016. The modified animal model used in this study allowed for assaying the effects of repairing agents on bone cells by determining the expression of important mediators involved in bone metabolism.…”

“…, Ruangsawasdi et al . ). The modified animal model used in this study allowed for assaying the effects of repairing agents on bone cells by determining the expression of important mediators involved in bone metabolism.…”

Immunohistological study of the effect of vascular Endothelial Growth Factor on the angiogenesis of mature root canals in rat molars

“…However, studies confirming this information were performed on culture cells or subcutaneous implantation. Ruangsawasdi, et al 25 (2016) demonstrated that the site can affect pulp regeneration. Considering that there are no in loco studies evaluating the angiogenesis on mature root canals, this study aimed to analyse the effect of VEGF on the angiogenesis of mature root canals in rat molars.…”