An in vitro approach for the study of dentinogenesis by organ culture of the dentine–pulp complex from rat incisor teeth

Culture of the developing dental tissues has contributed to understanding of developmental processes during early odontogenesis. However, to understand fully the mechanisms involved during dentinogenesis and tissue repair there is a need to develop culture models for the dentine–pulp complex from more mature dental tissues. This study describes the development of a system for the organ culture of mature rodent teeth. Slices of incisors from 28-day-old rats were embedded in a semisolid, agar-based medium and cultured on floating Millipore filters at the liquid–gas interface for up to 14 days. Preservation of cell and tissue morphology was observed throughout the entire dentine–pulp complex after each culture period and autoradiographic studies showed that the odontoblasts were actively synthesizing and secreting extracellular matrix during culture. Transmission electron microscopy confirmed that the phenotypic morphology of the odontoblasts had been maintained during culture. These results demonstrate that the dentine–pulp complex from mature rodent tissues can be cultured successfully for substantial periods of time and will provide a useful model for the study of dentinogenesis and tissue repair.