Molecular factors resulting in tooth agenesis and contemporary approaches for regeneration: a review.

AIM: This review discusses the complex epithelial-mesenchymal interactions that occur during tooth development and systemic anomalies that may result in hypodontia. Emphasis is placed on four interacting signaling families (Shh, FGF, BMP, and Wnt) that have been identified for their integral role in complete tooth development and on several genetic mutations in the MSX1, PAX9, EDA, and AXIN2 genes that arrest tooth development. Proposed treatment options are presented, including signaling factor supplementation and stem cell isolation for bioengineering new teeth.