An In Vivo Model for Short-Term Evaluation of the Implantation Effects of Biomolecules or Stem Cells in the Dental Pulp

Abstract

The continuously growing rodent incisor is a widely used model to investigate odontogenesis and mineralized tissue formation. This study focused on evaluating the mouse mandibular incisor as an experimental biological tool for analyzing in vivo the capacity of odontoblast-like progenitors or bioactive molecules to contribute to reparative dentinogenesis. We describe here a surgical procedure allowing direct access to the forming part of the incisor dental pulp Amelogenin peptide A+4 adsorbed on agarose beads, or dental pulp progenitor cells were implanted in the pulp following this procedure. After 10 days A+4 induced the formation of an osteodentin occluding almost the totality of the pulp compartment. Implantation of progenitor cells leads to formation of islets of osteodentin-like structures located centrally in the pulp. These pilot studies validate the incisor as an experimental model to test the capacity of progenitor cells or bioactive molecules to induce the formation of reparative dentin.

Concomitant multipotent and unipotent dental pulp progenitors and their respective contribution to mineralised tissue formation

“…Ten-week-old mice C57Bl-6 male (25 g) (Charles Rivers, l'Arbresle, France) (n = 6 for each group) were anaesthetised by intraperitoneal administration of ketamine (100 mg/kg of body weight)/xylazine (10 mg/kg of body weight). Cell implantations in the incisor were performed as described (Lacerda-Pinheiro et al, 2008).…”

“…Mandibles were subjected to micro-scanner analyses with a 1072 Skyscan® micro-CT (Skyscan®, Kontich, Belgium) as described in (Lacerda-Pinheiro et al, 2008). For immunohistochemical analyses, mandibles and calvaria were fixed in PFA 4 % at 4 °C overnight, and demineralised for 2 months in buffered EDTA 4.13 %.…”