polymers Review Hydrogels and Dentin–Pulp Complex Regeneration: From the Benchtop to Clinical Translation Marwa M. S. Abbass 1,2 , Aiah A. El-Rashidy 2,3 , Khadiga M. Sadek 2,3 , Sara El Moshy 1,2, Israa Ahmed Radwan 1,2 , Dina Rady 1,2 , Christof E. Dörfer 4 and Karim M. Fawzy El-Sayed 2,4,5,* 1 Oral Biology Department, Faculty of Dentistry, Cairo University, Cairo 11562, Egypt;
[email protected] (M.M.S.A.);
[email protected] (S.E.M.);
[email protected] (I.A.R.);
[email protected] (D.R.) 2 Stem Cells and Tissue Engineering Research Group, Faculty of Dentistry, Cairo University, Cairo 11562, Egypt;
[email protected] (A.A.E.-R.);
[email protected] (K.M.S.) 3 Biomaterials Department, Faculty of Dentistry, Cairo University, Cairo 11562, Egypt 4 Clinic for Conservative Dentistry and Periodontology, School of Dental Medicine, Christian Albrechts University, 24105 Kiel, Germany;
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[email protected] Received: 22 October 2020; Accepted: 10 November 2020; Published: 9 December 2020 Abstract: Dentin–pulp complex is a term which refers to the dental pulp (DP) surrounded by dentin along its peripheries. Dentin and dental pulp are highly specialized tissues, which can be affected by various insults, primarily by dental caries. Regeneration of the dentin–pulp complex is of paramount importance to regain tooth vitality. The regenerative endodontic procedure (REP) is a relatively current approach, which aims to regenerate the dentin–pulp complex through stimulating the differentiation of resident or transplanted stem/progenitor cells.