This study summarizes the recent cutting-edge approaches for dentin regeneration that still do not offer adequate solutions. Tertiary dentin is formed when odontoblasts are directly affected by various stimuli. Recent preclinical studies have reported that stimulation of the Wnt/β-catenin signaling pathway could facilitate the formation of reparative dentin and thereby aid in the structural and functional development of the tertiary dentin. A range of signaling pathways, including the Wnt/β-catenin pathway, is activated when dental tissues are damaged and the pulp is exposed. The application of small molecules for dentin regeneration has been suggested as a drug repositioning approach. This study reviews the role of Wnt signaling in tooth formation, particularly dentin formation and dentin regeneration. In addition, the application of the drug repositioning strategy to facilitate the development of new drugs for dentin regeneration has been discussed in this study.

It is well understood that developing new drugs is one of the highest value-added businesses in a country; however, the current governments' spending in pharmaceutical research and development(R&D) is minimal in Korea. This paper suggests that different governmental bodies should take in charge of different stages of the R&D process in order to maximize the use of limited government research funding. First, during the initial phase of the drug development, including clinical trials, the Ministry of Education, Science and Technology is the most appropriate governmental organization to support the research. For later procedures such as supporting the industries for exporting developed drugs, legislative approvals, and building infrastructure for future clinical trials should be supported by the Ministry of Knowledge and Economy and the Ministry of Health and Welfare along with the Korea Food and Drug Administration(KFDA). The KFDA, which is the main governmental agency approving newly developed drugs in the market, will need to take a crucial responsibility in the initial phase of the pharmaceutical R&D by guiding the industries with timely and proper information. As a first step, it is recommended to set up and operate a center for supporting new drugs, so that the industries can facilitate the development of marketable drugs which meet customers' needs. Later, in order to expedite the process of exporting and getting approvals of the newly developed drugs from foreign countries, it is necessary to develop new approval system, which includes introduction of the Good Manufacturing Practice (GMP), mandatory validation system, and education program for supporting expertise. Lastly, the KFDA needs to take an active role in developing Korean pharmaceutical industries by communicating with other foreign governments with regards to the globalization of the Korean pharmaceutical industries. For example, as a follow up after the Free Trade Agreement(FTA), active discussion on GLP of Mutual Recognition Agreement(MRA) with the United States of America, should be seriously considered.