Lose a Tooth? Stem Cell Technique May Restore It
Once people are past the tooth fairy stage of life, losing a tooth is often associated with gum disease and generally not a positive event. Researchers have now developed a stem cell technique that has successfully restored molars in rats and may someday lead to restoring teeth in humans.
Stem cell technique may restore teeth lost to gum disease
According to the US Department of Health and Human Services, the average American loses about eight teeth by the time he or she reaches age 50. One reason for tooth loss is gum (periodontal) disease.
Gum disease affects about 80 percent of adults in the United States. The disease can range from simple inflammation of the gums to a serious condition called periodontitis, in which the gums pull away from the teeth and infections form. Toxins break down the bone and connective tissue that hold the teeth in place. If not treated, the teeth may become loose and need to be removed.
Risk factors for gum disease, according to the National Institute of Dental and Craniofacial Research, include smoking, diabetes, hormonal changes in females, use of certain medications, illnesses such as cancer or AIDS, and genetics.
At the University of Illinois at Chicago, researchers used stem cells gathered from the molars in mice and prepared them for reinsertion into the tooth sockets of rats. After two and four months, the stem cells formed new attachments between the tooth and bone, firmly attaching the tooth into the animal’s mouth.
Smit Dangaria, a bioengineering doctoral candidate who conducted the study, noted that in the control group, in which molars were replanted without using stem/progenitor cells, the teeth were either lost or only loosely attached and resorbed.
Dangaria explained that “our research uncovered the code required to reattach teeth—a combination of natural tooth root surface structure together with periodontal progenitor cells.” Senior author Tom Diekwisch, director of the Brodie Laboratory, noted that their work was the first progenitor cell-based regeneration of a complete periodontal ligament that resulted in an attached, functional tooth.
In 2007, a Japanese team reported in Nature Methods that they had successfully regrown a tooth from cells taken from mouse embryos. The researchers transplanted the tooth into an adult mouse, and the tooth bud grew to full size.
Diekwisch pointed out that the approach used by the University of Illinois team “could be used for replanting teeth that were lost due to trauma or as a novel approach for tooth replacement using tooth-shaped replicas.” This pioneering work in stem cell technology may soon result in a new option for people who lose a tooth.
Chu J. Technology Review 2007 February
Nakao K et al. Nature Methods 2007 Mar; 4(3): 227-30
National Institute of Dental and Craniofacial Research
University of Illinois at Chicago