Medicine to regrow teeth? Here’s what we know about the experimental medicine advanced to clinical trials in Japan

The trial will focus on patients affected by anodontia, a genetic condition resulting in the absence of teeth, or partial anodontia, where individuals are missing some teeth, as described by the National Organization for Rare Disorders (NORD).

Scheduled to commence in July 2024, the clinical trials will take place in Japan. Should the results prove successful, regulatory approval for the medicine is anticipated by 2030, offering potential revolutionary advancements in the field of dentistry.

‘Every dentist’s dream’

Dr. Katsu Takahashi, the head of the dentistry and oral surgery department at the Medical Research Institute Kitano Hospital, expressed his enthusiasm for the concept of growing new teeth. “The idea of growing new teeth is every dentist’s dream,” Dr. Takahashi stated in an interview with Mainichi.

Dr. Takahashi’s pursuit of this dream began during his graduate student years and has continued ever since. Following his dental education, he embarked on graduate studies in molecular biology at Kyoto University in Kyoto, Japan, in 1991. During this time, research in the United States was exploring genes that could influence tooth growth in mice, and Dr. Takahashi was drawn to this field.

His journey took him to the United States, where he joined the research community exploring the potential of these genes and their impact on tooth development. Dr. Takahashi’s dedication and passion have been instrumental in bringing him closer to turning his dream into a reality.

What is the research behind experimental medicine to regrow teeth?

Upon discovering that a single gene mutation could influence the number of teeth, Dr. Takahashi embarked on further investigations to target specific genes capable of promoting tooth growth.

Around 2005, Dr. Takahashi returned to Kyoto University, where he collaborated with researchers who had identified a gene responsible for producing a protein called USAG-1. This protein was found to limit the number of teeth that could develop.

Recognizing the potential implications, Dr. Takahashi’s research team focused on developing an antibody that could bind to the USAG-1 protein, effectively blocking its function. The hypothesis was that inhibiting this protein could potentially stimulate the growth of additional teeth.

It is important to note that the concept of utilizing neutralizing antibody therapy for tooth tissue regeneration is relatively new, as reportedly observed by Kennedy, an independent expert not involved in the study.

In laboratory experiments conducted in 2018, mice with a naturally limited number of teeth exhibited the growth of new teeth after receiving the antibody-based medicine. This outcome provided promising evidence for the potential effectiveness of the treatment approach.

FAQs:

1. Which animals can regrow teeth?
   Several animal species possess the remarkable ability to regrow teeth. Among them are sharks, lizards, geckos, horseshoe crabs, and axolotls. Sharks, for instance, possess multiple rows of teeth, allowing them to continuously replace lost teeth. Within a span of a few weeks, a new tooth can grow to replace the one that was shed. In the case of lizards, their teeth are anchored to their jaws by a single root. When a tooth is lost, the root will naturally detach, leading to the growth of a new tooth in its position. This natural mechanism enables these animals to maintain their dental structure and functionality, presenting an intriguing phenomenon within the animal kingdom.
2. How many teeth do humans have?
   In the human dental structure, there are a total of 28 permanent teeth, or 32 if one includes the wisdom teeth. The initial set of teeth, commonly referred to as baby teeth, milk teeth, or primary teeth, consists of 20 teeth. These teeth start to emerge around the age of 6 months. As children grow, the transition to permanent teeth begins at around 6 years old and continues until approximately 12 or 13 years old. Each jaw contains 8 incisors, 4 canines, 8 premolars, and 4 molars. Wisdom teeth, which are the fourth set of molars, generally erupt between the ages of 17 and 25. However, it is important to note that not everyone develops wisdom teeth, and in cases where there is insufficient space in the jaw, their removal may be necessary.