By Dr. Joseph D. Lim
It’s a process that has nothing to do with Taal and Kanlaon, both recently exhibiting signs of restlessness.
It’s called an eruption, the early stage in our lives baby teeth is lost. It sets the opening for stronger permanent teeth.
Trivia: Rabbits never stop regrowing their teeth, a process not available to humans — except for that first set of baby teeth. Indeed, is it possible at all to regrow our teeth?
It’s not for lack of trying. Therapeutics, stem cells, gene-editing — all are being tried in the effort to regrow teeth.
Bioengineering may have the answer. Scientists are now toying with the idea of using stem cells inside the tooth to regrow tooth.
“If we can learn how other animals are able to regrow their teeth from stem cells, we could actually really grow a full, new tooth in vitro,” Dr. Ophir Klein, a professor of orofacial sciences and pediatrics at the University of California, San Francisco, tells Harri Elizabeth Weber of Popular Science.
“The tooth, by itself, is one challenge, getting it to become part of bone, integrating into your jaw, is another aspect of regeneration,” Dr. Salvador Nares, a professor in the periodontics department at the University of Illinois, Chicago’s College of Dentistry, tells the magazine. “Ultimately, the vision would be to seed, if you will, some sort of capsule or something within the gum tissue, and then let it grow out into a tooth.”
Then again, the tooth has to stop growing “because if it keeps growing, then that’s called cancer,” says Dr. Nares.
His colleague, Dr. Afsar Naqvi, an associate professor, says gene editing is very promising. That is, he says, using patients’ own cell types, guiding them into the desired cell type, and using it for repair and regeneration.
Then there’s an antibody drug that targets a gene (USAG-1) which is not specific to the dental tissues. Dr. Naqvi, however, raises the question: What if beyond tooth growth, “it affects our bone growth in a positive, negative or whatever manner? It has to be controlled.”
Regrown tooth may still be far away as things stand now, what with safety issues, safety trials on humans, regulatory rules and more research and development that need to be conducted.
Be satisfied with what you have. Our unique teeth has grown through millennia of evolution, and its suitable as it is for that perfect smile, not to say of being able to bite and chew through our nutrition needs.
Just be sure to brush after every meal, at least twice a day — and floss. And don’t forget to visit the dentist for cleaning.
Remember, keep all the germs away — they cause tooth decay, cavities and gum disease and loosen teeth in the long run.
As it is, dentures and implants are our best alternative to lost tooth.
You have to give it to the Japanese when it comes to innovation.
Toregem Biopharma, a Japanese company, is trying how best to regrow teeth with a new drug that stimulates the human body to replace lost teeth.
Dr. Katsu Takahashi, an oral and maxillofacial surgeon at Kyoto University, developed the antibody drug for tooth regeneration.
The method uses the antibody drug to interact with the USAG-1 gene found in the undeveloped tooth buds of some adults. Normally, the gene stops the tooth buds from forming into teeth. Dr. Takahashi believes that by preventing the gene to stop tooth buds forming into teeth, they mature into teeth.
For the first time this year, Toregem Biopharma will attempt to experiment the drug among children with anodontia, a condition when they cannot develop adult teeth.
The method has never been tried among humans before. However, a 2018 study of ferrets showed that they developed new teeth when given the drug.
“The idea of growing new teeth is every dentist’s dream,” Dr. Takahashi, who co-founded the company, told The Mainichi newspaper.
In the future, perhaps as early as 2030 according to Toregem Biopharma, replacing teeth would be as simple as injecting the antibody medicine.
The first breakthrough came in 2007 when a model mouse with supernumerary teeth (more teeth than usual) was discovered. The USAG-1 gene deficiency was found to be the cause for supernumerary teeth in the model mouse.
Additional teeth were found to grow from the surviving tooth buds, which normally degenerate and disappear. Until then, some gene-deficient mice with fewer teeth were known, but mice with more teeth were very rare.
Based on the mouse findings, Toregem Biopharma researchers though whether teeth could be regenerated in humans with congenital and/or acquired tooth defects by inactivating USAG-1 protein with a drug.
To test the hypothesis they used mouse anti-USAG-1 antibodies to check the biological activity of antibodies. Currently, they are humanizing three antibodies that are effective in growing teeth when administered to mice and dogs with less number of teeth.
Based on the gene status, the aim is to inject a one shot antibody to treat congenital or partial anodontia patients for tooth regeneration.
That is good news in Japan where more than 43 million 60 years or older have lost one or more teeth due to decay or gum disease. Indeed, about one in 10 patients with hereditary congenital tooth defect and partial tooth loss happen to be diagnosed when the patients visit a pediatric dentist for treatment of tooth loss.
Toregem Bio Pharma Co., Ltd. is a startup venture from Kyoto University that was founded in May 2020 for the purpose of research and development and launch of tooth regeneration antibody drug based on the research results of Dr. Takahashi.
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Dr. Joseph D. Lim, Ed. D., is the former Associate Dean of the College of Dentistry, University of the East; former Dean, College of Dentistry, National University; Past President and Honorary Fellow of the Asian Oral Implant Academy; Honorary Fellow of the Japan College of Oral Implantologists; Honorary Life Member of the Thai Association of Dental Implantology; and Founding Chairman of the Philippine College of Oral Implantologists. For questions on dental health, e-mail jdlim2008@gmail.com or text 0917-8591515.
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Dr. Kenneth Lester Lim, BS-MMG, DDM, MSc-OI, graduated Doctor of Dental Medicine, University of the Philippines, College of Dentistry, Manila, 2011; Bachelor of Science in Marketing Management, De La Salle University, Manila, 2002; and Master of Science (MSc.) in Oral Implantology, Goethe University, Frankfurt, Germany, 2019. He is an Associate Professor; Fellow, International Congress of Oral Implantologists; and Fellow, Philippine College of Oral Implantologists. For questions on dental health, e-mail limdentalcenter@gmail.com/WDJ