all dental medicine stories

Treasures of Dental School’s old museum opened wide at exhibit

50443248 — Tue, 02 Oct 2007 13:21:28 -0400

The Harvard Dental Museum once held 14,000 specimens, everything from Ralph Waldo Emerson’s dentures to a prehistoric mastodon’s tusk measuring 11 feet in length and weighing 300 pounds.

Emerson’s dentures, which were manufactured around 1870 and are made of porcelain and set in vulcanized rubber, are still extant. But the mastodon’s tusk is nowhere to be found. Only an article from a 1929 issue of the Boston Globe remains, describing how the 50,000-year-old tusk was found near the Arctic Circle and transported by dogsled and boat to Boston.

Key to dental enamel formation found

50443248 — Wed, 25 Jul 2007 14:59:57 -0400

Scientists at Harvard-affiliated Forsyth Institute have found and replicated a key aspect of the mechanism by which dental enamel is formed.
The findings, published in the Feb. 14 Journal of Structural Biology, may lead, one day, to new, biological methods for repairing teeth and other mineralized tissues as well as to new, very hard ceramic materials.

Lead author Elia Beniash, staff scientist at Forsyth, explains that enamel, the hardest tissue in the human body, is composed mainly of calcium phosphate mineral crystals. "It is well known that enamel's strength and durability derive from the unique way in which those crystals are organized into parallel bundles called 'rods.'

"In the current research, carried out in test tubes, we demonstrated that the protein amelogenin plays a key role in regulating the organization and growth of these crystals and how it works. We also determined that newly forming enamel structure emerges as a result of cooperative interactions between forming crystals and assembling proteins, rather than sequentially, as in the formation of other mineralized tissues such as bone and dentin [the bony material found under enamel, in teeth]." The scientists worked with mouse amelogenin, which is very similar to the form of the protein found in human teeth.

Henry Margolis, chair of the Forsyth Department of Biomineralization and a co-author of the article, said, "The current findings are a crucial step toward understanding the process of enamel formation. We hope this work will one day lead to an ability to repair damaged tooth enamel."

Another long-term goal is the development of biomimetic, nanostructured materials with properties similar to those of dental enamel. Biomimetic materials or devices are those whose design, organization, and functional properties are modeled on biological systems. Nanostructured materials are those in which the organization is regulated at the submicron level during fabrication. "Such advances will rely on future collaborative studies involving chemists, biophysicists, biologists, and materials scientists," Margolis said.

In addition to his Forsyth appointment, Margolis is associate professor in the Department of Oral and Developmental Biology at the Harvard School of Dental Medicine. The team also included James P. Simmer, associate professor of biologic and materials sciences in the Division of Prosthodontics at the University of Michigan. The research was funded by a grant from the National Institute of Dental and Craniofacial Research and through support provided by The Forsyth Institute.

Regrowing missing teeth may someday be possibility

70652986 — Mon, 26 Mar 2007 05:25:51 -0400

Regrowing missing teeth may someday be a possibility, based on work by a team of scientists at the Forsyth Institute, an independent, Harvard-affiliated research organization specializing in oral and craniofacial biology. Pamela Yelick, an assistant staff member at the Forsyth Institute and an instructor in oral and developmental biology at the Harvard School of Dental Medicine, says that the research she and her colleagues have carried out should result in a clinical product in about 15 years. "Or maybe sooner. That's probably a pretty conservative estimate," Yelick said. The successful tissue engineering experiment was reported in an article by Yelick and her colleagues in the Oct. 1, 2002, issue of the Journal of Dental Research.

Mammalian teeth regrown in lab

70652986 — Mon, 26 Mar 2007 05:24:27 -0400

A study involved seeding cells from the immature teeth of six-month old pigs onto biodegradable polymer scaffolds. The researchers then placed these structures into rat hosts. Within 30 weeks, small, recognizable tooth crowns had formed. These contained dentin; odontoblasts, cells that secrete dentin-forming protein; a well-defined pulp chamber; Hertwig's root sheath epithelia; cementoblasts, which form a mineralized tissue that covers the roots; and a morphologically correct enamel organ. The results, demonstrated in some two dozen experiments, represent the first successful generation of mature tooth crowns containing both dentin and enamel. They also suggest that it may be possible to grow teeth of a particular size and shape, according to principal investigator Pamela Yelick, Harvard School of Dental Medicine instructor in oral and developmental biology at the Forsyth Institute and an assistant member of the Forsyth staff. The research was reported in the Oct. 1, 2002, Journal of Dental Research.

Bad dental health could affect military readiness

70652986 — Mon, 26 Mar 2007 05:22:17 -0400

Phillip Dexter Woods is a dentist and an Army reservist. Until he graduated in June 2002, Woods was also a student in a master's program at the Harvard School of Public Health. As a student, Woods was particularly interested in studying the dental health of Army recruits and their resulting availability for deployment. What he found troubled him. An oral health survey of military recruits conducted by the Department of Defense in 2000 indicated that an increasing number of recruits were coming to the service with oral health problems, while the number of practicing military dentists was decreasing. From that perspective, oral health can be seen as a national security issue, Woods said.

Will vaccine defense help polish off tooth decay?

70652986 — Mon, 26 Mar 2007 05:14:47 -0400

The key to preventing cavities in teeth lies in controlling an acid-secreting bacterium known as Streptococcus mutans that lives in the mouth. Researchers at the Harvard School of Dental Medicine believe they can prevent cavities for life by vaccinating babies against S. mutans. "If we can get the babies immunized before the bacteria have had a chance to colonize, then we can offer protection for perhaps the rest of their lives," said Daniel Smith, HSDM associate clinical professor of oral biology and pathophysiology. Smith and Martin Taubman, professor of oral biology at HSDM, have worked to develop a vaccine that is effective and easily administered.