Oral Sci Int. 2019;1–7. wileyonlinelibrary.com/journal/OSI | 1 © 2019 Japanese Stomatological Society 1 | INTRODUCTION Teeth are dental hard tissues that show very limited capability of re- generation. Enamel possesses no regenerative capacity while very limited regenerative capacity is seen in the dental pulp, dentin, and periodontium, thereby posing a substantial challenge toward their therapeutic treatment. 1 Many sophisticated dental materials can be used for partial tooth regeneration, whereas novel dental implants can be used for replacement of the tooth. 2 The primary drawback of using these dental materials and implants is the alteration in the physiological functioning of the tooth. For example, during classical endodontic therapy, the pulp is extirpated, increasing the chances of tooth fragility and fracture. In this process, the dental pulp is lost, which was a living, dynamic structure that provided strong me- chanical support and protection from the microbial-rich oral envi- ronment. 2,3 In this context, the concept of biological regeneration is an extremely useful option and supplement to customary surgical techniques for prosthetic replacement of tissues and organs. Several cell-based therapeutic approaches are already being successfully ap- plied in clinics. These studies involve in vitro manipulation of stem cells and their consequent administration to patients as living and dynamic biological agents. 4 This review is an attempt to better understand various aspects of biological regeneration of tooth structures. It gives a conceptual exploration of what we can expect from regeneration of a part of a tooth or a whole tooth and the various factors involved in achieving the ultimate goals of regeneration in which a fully restored and func- tional tooth is regenerated with the help of regenerative medicine using human stem cells. The ultimate goal is to regenerate anatom- ically correct, entire tooth organs with the enamel, dentin, cemen- tum, and dental pulp, as well as the periodontal ligament, using clinically compatible cell types and approaches. 5 1.1 | Understanding the concept of regeneration Humans possess a relatively poor regenerative ability compared to some invertebrates that possess an extraordinary capacity to regenerate even highly complex tissues. 6 As regards healing of in- jured tissues, the term “repair” is defined as the restoration of tissue architecture and function after an injury. This definition lacks the word “complete” and hence repair can be incomplete or refer to an altered restoration of original architecture and physiological func- tion. Repair can occur by two separate processes: regeneration and replacement. Regeneration refers to a type of healing in which new Received: 26 May 2018 | Revised: 3 November 2018 | Accepted: 5 December 2018 DOI: 10.1002/osi2.1017 REVIEW ARTICLE The ultimate goals of tooth regeneration: Where do we stand? Wasim Kamate | Nupura Vibhute | Rajendra Baad | Uzma Belgaumi | Vidya Kadashetti | Sushma Bommanvar Department of Oral Pathology and Microbiology, School of Dental Sciences, Krishna Institute of Medical Sciences Deemed University, Karad, India Correspondence Wasim Kamate, Department of Oral Pathology and Microbiology, School of Dental Sciences, Krishna Institute of Medical Sciences Deemed University, Karad-415110, India. Email: drwasimmds@outlook.com Abstract The concept of tooth regeneration has fascinated many researchers recently. Several studies have been conducted in an attempt to regenerate either parts of tooth or a whole tooth. Although teeth and its constituent parts have very limited or no capaci- ties of regeneration, several ex vivo and animal studies have exploited the use of stem cells to regenerate parts of a tooth or a whole tooth. This review is an attempt to better understand various aspects of biological regeneration of tooth structures. It gives a conceptual exploration of what we can expect from regeneration of a part of a tooth or a whole tooth and the various factors involved in achieving the ultimate goals of regeneration in which a fully restored and functional tooth is regenerated with the help of regenerative medicine using human stem cells. KEYWORDS regeneration, repair, stem cells, tooth