Yes, It Can Be a Jungle Out There

By David G. Jones

Endodontist W. Paul Brown, DDS, waits for the uncooperative patient to be anesthetized then performs a root canal on an abscessed tooth. After the procedure is finished, the patient gradually awakens, blinks his eyes a few times, then stands to his full 10-foot height.

The Kodiak bear, a San Francisco Zoo resident, is just one of the many animals Brown has worked on during a 17-year relationship with animal dentistry. General dentist Robert W. Turner, DDS, Brown's daughter Sarah de Sanz, DDS, and endodontist A. Scott Cohen, DDS, form the rest of the team which visits the zoo and Marine World Africa USA in Vallejo six to 10 times a year to work on assorted teeth, fangs, beaks and tusks.

Veterinarians are familiar with the anatomy of many different animals, but most are not trained in dentistry. In a chance encounter in the early years of his practice, one of Brown's patients was a San Francisco Zoo veterinarian.

"I asked him how the zoo managed animals with dental problems," Brown says. "The vet said they were paying a lot of money to have a dentist fly up from L.A. to perform this service. I told him that I would provide the treatment free of charge."

Brown then teamed with Turner, and together they've since worked on koalas, lions, tigers, bears, snow leopards, jaguars, African wild dogs, orangutans, chimpanzees, gorillas, spider and green monkeys, horses, camels, bobcats, elephants, sea lions, killer whales, seals, dolphins and walrus. They've even mended the beaks of a dove and a small turtle.

A second-year endodontics resident at the University of California, San Francisco, de Sanz has worked with her father on animals since she was a second-year dental student at UCSF in 1990. Cohen and de Sanz were classmates in dental school, and he joins the group when needed on endodontic cases.

"The basic anatomy of animal teeth is similar to that of humans, with enamel, dentin, pulp and cementum, but in different shapes and sizes," Cohen says. "We apply dentistry to animals, similar in many respects to human dentistry."

When Brown and Turner began, they had no knowledge of animal dentistry.

"We learned strictly from looking at animal skulls at the Berkeley Hall of Science," Turner recalls. "We took x-rays of teeth and skulls and tried to evaluate the anatomical differences that way. Paul then would work out the file system for root canals, and I'd work out post variations for the inside of the canal."

The large number of anatomical variations among various species required some ingenuity and trial-and-error to develop instruments for use on animals. Large cats and other carnivores, for instance, have specialized teeth, such as long, sharp canines which require special instruments. Most of the equipment is made by a surgical supply company in Burlingame, and a local lab makes the crowns.

"From a restorative standpoint, the most difficult challenge involves making posts that fit into long, curved canals, but are strong enough to withstand the forces large animals put on them," Turner says. "Earlier, I tried to use pre-cast posts, which in many cases either fell out or fractured. I experimented with different materials and wound up using an implant-grade surgical steel post."

Brown also had to go to some lengths to find suitable instruments.

"One of my patients, a Nobel Prize winner in physics, made me a special lentula spiral so I could work on a lion," Brown says. "I also asked for an endodontic file and an orthodontic wire to be precision machined together to make a long, flexible, narrow file for use in the elongated, curved canals in lion, tiger or gorilla canine teeth."

He describes another case where an elephant had cracked the tip of its tusks.

"The Stanford engineering department cast the crowns, and we installed them," Brown says.

Other differences between human and animal dentistry make treatment more difficult. For example, almost all animals undergoing dental treatment must be anesthetized, because they won't remain still for long periods. The roots of many animals' teeth often are deeply buried within thick bone, making extractions more difficult. And custom impression trays are necessary because of the variety of mouth sizes and shapes.

"We couldn't use a full arch impression tray because of the divergence of the teeth," Turner says. "I could put it in but couldn't get it back out after the impression was formed. We finally went to quadrant trays and pieced the arches together, and that worked well."

According to de Sanz, most dental problems animals encounter are trauma-related.

"They fracture their teeth and expose the nerve, requiring endodontic treatment to prevent abscess formation," she says. "If they break their teeth, they would die in the wild as a result, because they can't eat their normal diet."

Sometimes routine, the work can also be exciting, dramatic and dangerous.

"We trust that the vets are doing a good job keeping the animals under anesthesia, but we did have a large male tiger wake up while we were getting a bite registration, and all the vets and technicians jumped on him and held him down until we finished," de Sanz says.

The team has worked on animals for movies, and once worked on the Exxon tiger's teeth. Later this month, the father-daughter team will gain even more attention. Brown and de Sanz will be featured on a National Geographic Explorer segment on exotic animal dentistry. It is scheduled for broadcast at 7 p.m. June 21 on TBS.

They Like You,

They Really Like You

Dentists are among the most trusted professionals in the United States, according to a poll conducted in the fall of 1997 by CNN, USA Today, and the Gallup Organization.

Dentists ranked fifth in the poll, which has been conducted annually since the early 1980s. The 1997 poll, which ranked 26 professions, showed that 54 percent of American consumers rated the honest and ethical standards of dentists as "high" or "very high."

Pharmacists ranked first with 69 percent of American consumers rating their honesty and ethical standards as "high" or "very high." Clergy ranked second with 59 percent; doctors were third with 56 percent; and college teachers were fourth with 55 percent.

Engineers and police officers tied for sixth with 49 percent; funeral directors had 36 percent; and bankers had 34 percent. Journalists completed the top 10 with 23 percent.

Dentists have finished in the top five every year but one since the poll was first conducted. The only time dentists did not finish in the top five was the year following the David Acer/Kimberly Bergalis case in which there was public concern that dentists could transmit HIV to patients. In that year, dentists finished sixth.

Women Continue to Gain Ground

In the past decade, the number of women joining the profession, enrolling in dental schools and joining the faculty of those institutions has dramatically increased, reports the April issue of AGD Impact.

In 1968, women made up just 1.2 percent of all dentists, and in 1983, just 3 percent. In 1997, 12 percent of all dentists were women; women now account for 36 percent of all dental school students. In fact, women outnumber men at the Dental College at Howard University in Washington, D.C., and make up half -- or nearly half -- of all students at several other dental schools. That trend may continue as more women who might have once chosen careers in dental hygiene now consider being a dentist a viable option.

"There is a place for women in every aspect of dentistry," says June Warren Lee, DDS, past president of the American Association of Women Dentists. "Years ago women were encouraged to go into pediatric dentistry rather than pursue traditionally male areas. That's not happening today."

But women still have a way to go. Some female dentists say they are not always judged solely on their abilities -- a problem not unique to dentistry. And some say a "glass ceiling exists relative to obtaining leadership positions -- the overwhelming majority of which are held by men. In California, 3,400 women practice dentistry, about 13 percent of all dentists. CDA has total membership of about 17,550, and of that number, 2,300 are women, also 13 percent. The association is lead by 43 trustees, none of whom is a woman. The association has 15 standing councils and committees, and two are chaired by women.

While most dentists are owners or share ownership of their practices, a greater proportion of owners is more likely to be men than women. Men are also more likely to be solo private practitioners, and women are likely to be in group practices. Studies have shown that women, on average, work slightly fewer weeks per year and slightly fewer hours per week, and that women have been shown to spend slightly more time with each patient.

Strings Can Tangle Research Gifts

University researchers think corporations often place restrictions on research gifts and expect returns that may pose problems for recipients and institutions, according to an article in the April 1 issue of the Journal of the American Medical Association.

Eric G. Campbell, PhD, of Massachusetts General Hospital and Partners Healthcare System, Inc., Boston, and colleagues, surveyed 3,394 life science researchers at the 50 universities that received the most research funding from the National Institutes of Health in 1993. The survey asked if the scientists had received any research-related corporate gifts over the past three years, and if so, how important the gifts were to their research. The authors also wanted to know what, if anything, the recipients thought donors expected in return for their gift.

A significant number of respondents said they believe companies expected something in return for gifts:

* Thirty-two percent reported that the donor wanted pre-publication review of any articles or reports stemming from the use of the gift.
* Nineteen percent indicated a donor expected ownership of all patentable results from research for which a gift was used.
* Thirty percent indicated the company expected testing of their products.

Researchers also found that more than half the recipients reported that donors expected acknowledgment in publications (63 percent); that the gift not be passed to
a third party (60 percent); and that the gift be used only for the agreed-on purposes (59 percent).

The authors received responses from 2,167 faculty members, or 64 percent of those surveyed. They found that 43 percent of respondents received a research-related gift in the previous three years independent of a grant or contract. Of those who received a gift, 66 percent reported the gift was important to their research. They continue: "The most frequently received gifts were biomaterials (24 percent), discretionary funds (15 percent), research equipment and trips to meetings (11 percent each), support for students (9 percent), and other research-related gifts (3 percent)."

The authors suggest several general guidelines concerning corporate gifts. "First, faculty should become familiar, if they are not already, with their institutional policies that govern gifts vs. grants and contracts. Second, if existing policies regarding gifts are inadequate, academic institutions should develop through faculty new or revised policies that simultaneously encourage the sharing of resources and timely dissemination of results to the academic community and at the same time protect the legitimate interests of donors.

"Third, faculty should not accept any resources from a firm that expects ownership of intellectual property without an institutionally negotiated research grant or contract," the authors write. "Fourth, faculty bear the primary responsibility to avoid using the gift mechanism as a means to bypass existing institutional policies and administrative structures for exchanges that are more appropriately managed under the auspices of a research grant or contract."

The authors conclude that prohibiting or heavily regulating acceptance of gifts is not warranted. But they urge universities to monitor cases where expectations of return
clearly pose problems for the recipient or the institution. And they suggest: "At times it may be prudent for faculty members to 'look a gift horse in the mouth.' "

Radiation May Boost Stroke Risk

Patients with oral cancer who receive radiation therapy in the neck are five to six times more likely to have damaged carotid arteries that leave them more vulnerable to a stroke, according to a study published in the April issue of the Journal of Oral and Maxillofacial Surgery.

Each year, oral and maxillofacial surgeons, dentists and physicians diagnose more than 43,000 patients with oral cancer.

The X-rays of 61 male patients who had received radiation of the neck in the previous three years showed that 17 (nearly 30 percent) had calcified plaques obstructing at least one of their carotid arteries, with six showing artery blockage on both sides of the neck. In comparison, only three of the 61 patients in the control group had X-rays that revealed artery blockage.

Radiation oncologists often radiate the neck to kill oral cancer cells that have spread to lymph nodes. Patients receiving that therapy usually have other risk factors -- such as tobacco or alcohol abuse or hypertension -- that make them more susceptible to other health problems. All of the study group patients had already developed osteoradionecrosis of the mandible, which the study's authors contend should be considered a marker for potential artery complications.

"Our research shows that radiation can damage the carotid arteries lining each side of the neck and may induce atherosclerosis," says Dr. Arthur H. Friedlander, lead author of the study and chief of oral and maxillofacial surgery at the Veterans Affairs Medical Center, Sepulveda, Calif. "After enduring the trauma of fighting cancer, these irradiated patients are now at risk for stroke much earlier in life than those in the control group."

Atherosclerosis, a buildup of cholesterol and calcium in the inner layer of the arteries, kills more people in the United States than any other disease. Its first visible symptom is often a stroke, which affects 550,000 Americans each year and causes more than 150,000 deaths.

To identify whether they are at increased risk of stroke, oral cancer patients should ask their oral and maxillofacial surgeon or dentist to check their X-rays for calcium deposits in the neck. Many of those patients already see oral and maxillofacial surgeons for help in coping with dry mouth syndrome, an uncomfortable side effect of radiation.

Researchers Close in on Cause of Cleft Palate

Scientists at the University of Southern California have identified a genetic circuit that when broken causes cleft palate in newborn mice, according to a story in Dentistry Today.

The critical points of the circuit represent genes and gene products that interact with each other to direct palate formation. The surge that caused the circuit to break in the mice was an environmental assault in the form of steroid hormones given to female mice during pregnancy.

According to the study, which was partly supported by the National Institute of Dental Research, this is the first time that a cause-and-effect scenario for cleft palate has been worked out at the molecular level.

The finding may help define the genetic components of cleft palate in humans and explain the link of risk factors such as stress, smoking and certain medications that are known to elevate the level of steroids in the body.

"Facial clefting disorders are among the most common human birth defects and occur in almost 1 in 2,000 live births," says Dr. Tina Jaskoll, one of the study's principal investigators. "The defects can range in severity from a relatively minor split uvula at the rear of the mouth to a cleft running the length of the hard and soft tissues forming the roof of the mouth."

The more severe forms require surgery and are often associated with psychological and physical problems, she added.

The investigators believe cleft palate results from a combination of genetic and environmental factors, but attempts to identify those components in human populations have proved inconclusive.

Lower Doses, Less Pain

In the not-too-distant future, patients in pain may be better treated with fewer side effects using lower morphine doses combined with new painkillers already under development, according to a study reported by researchers from the University of California, San Francisco, in the March 26 issue of the journal Nature.

Pain may be perceived by most people as a continuum ranging from irritating to unbearable, but a UCSF research team led by Allan Basbaum, PhD, has made the discovery that -- biologically -- mild pain and more intense pain are distinct and governed by different signaling molecules. Effective management of intense pain should take those distinctions into account, Basbaum said.

"Pain is not a single phenomenon that can always be attacked with one type of analgesic drug," according to Basbaum.

Yu Qing Cao, a graduate student in Basbaum's lab, conducted key experiments on mice that revealed that two different types of signaling molecules, called neurotransmitters, are involved in mild pain and more intense pain.

For several years, researchers have known that the neurotransmitter glutamate is important is signaling pain. But Cao, along with researchers in the lab of Charles Epstein, MD, developed a "knockout" strain of mice lacking a gene for substance P and neurokinin A, two members of a different class of neurotransmitters called the tachykinins.

By measuring how long it took mice to move away from applied mechanical pressure, or how many seconds they licked skin where hot pepper extract had been applied, Cao determined that the knockout mice were as sensitive to mild pain as normal mice, but that they were much less sensitive to moderate or more intense pain.

The research team concluded that substance P or neurokinin A -- or both -- are needed to transmit moderate or more intense pain signals in a variety of painful conditions. Although the mutant and normal mice needed the same amount of morphine to relieve mild pain, the mutant mice, which lacked the tachykinins, needed less morphine to experience pain relief under more intense pain conditions.

Pharmaceutical companies have been developing prototype painkillers to block the action of substance P and neurokinin A on receptors on the surfaces of pain-transmitting nerve cells. The recent rodent studies by Basbaum and others are defining and refining scientific understanding of the roles played by those and other molecules in specific pain syndromes. Their findings point to strategies that might be adopted to design more effective drugs to individually target the various molecules.

Embezzlement is Serious but Avoidable

Dentists are among those victimized by embezzlers, but potential victims can protect themselves, reports the April 1998 issue of AGD Impact.

Theft by employees will cost American business $60.8 billion or more in 1998, according to data from the U.S. Department of Justice. Dentists can reduce their losses by watching for danger signs and taking preventive action.

"Any dental office is prone to embezzlement," warns John Sullivan, DDS, JD, a practice management consultant in Wheaton, Ill. The usual target, he said, is a dentist-owner who is extremely busy, quite successful, and over-reliant on one trusted employee.

Practice management experts list six warnings of embezzlement:

* Patients frequently complain about billing errors.
* One or more employees are living beyond their means.
* The office manager is overly protective of day sheets, ledgers, or computer records.
* An employee is volunteering too eagerly to open mail and go to the bank.
* Checking account statements continually fail to balance.

A few precautions can help dentists avoid becoming victims, says William Nicrosi, CPA, of the accounting firm of Williams, Taylor & Associates, PC, in Birmingham, Ala. He recommends keeping the staff in the picture.

"But it has to be done in a positive manner," he says. "Let the staff know you will be changing some procedures to make everyone feel better, to improve the practice, and to strengthen the dental team."

Nicrosi and the ADA offer seven anti-embezzlement tips:

* Pay attention to what's going on in your practice. Review collection records weekly; review financial statements and patient receivables monthly.
* Split up responsibilities. Have one person write deposit slips for checks, but have someone else take checks and deposit slips to the bank.
* Sign your checks personally. A signature stamp invites theft.
* Insist that employees take vacations. Embezzlers, fearing discovery, can't afford to be away from the office.
* Ask an expert. Hire an outside accountant to check your financial management system for weaknesses and suggest solutions.
* If you think someone is embezzling, see an accountant and attorney before you confront the employee. If you confront the person, do it privately and write down what is said.
* Finally, lead by example. Avoid using company checks or petty cash for personal items. Encourage your employees' honesty by your own honest performance.

Honors

Dr. Craig S. Yarborough has been named assistant dean for student services at the University of the Pacific School of Dentistry.

UOP has bestowed its 1998 Medallion of Distinction awards upon Dr. Ronald Borer, professor of endodontics and associate dean of clinical services; Dr. Louis Geissberger, immediate past president of the UOP Alumni Association; Arlene Burbank, former director of public relations; and Katherine Dugoni, wife of Arthur Dugoni, DDS, dean of UOP's School of Dentistry.

Upcoming Meetings

1998
May 6-10 American Association of Endodontists Annual Session, New York City (312) 266-7255, Ext. 3006
June 18-21 Infection Control in the Information Age: Access and Integration, Providence, R.I. (800) 298-6727
July 11-17 National Wellness Conference, Stevens Point, Wis. (800) 243-8694
Sept. 11-13 Oral Health 2000 Consortium, San Diego (312) 836-9900
Sept. 13-16 American Academy of Periodontology's Annual Meeting, Boston (312) 573-3210
Sept. 16-19 American College of Prosthodontists Annual Session, San Diego (800) 378-1260
Oct. 1-3 Annual Scientific Session of the Academy of Surgical Research, Nashville, Tenn. (612) 927-6707
Oct. 2-3 Society for Advanced Dentistry Inaugural Meeting, New Orleans (317) 290-2613
Oct. 8-12 World Dental Congress, Barcelona, Spain +44 171 935 7852
Oct. 8-10 American Society for Dental Aesthetics International Conference on Aesthetic Dentistry, Chicago (800) 454-2732
Oct. 24-28 ADA Annual Session, San Francisco (312) 440-2500
Oct. 31-Nov. 3 Pacific Coast Society of Orthodontists Annual Session, Palm Springs, Calif. (415) 441-2410
Nov. 19-21 International Dental Showcase, NEC Birmingham, U.K. 01722 335599

1999
April 8-11 CDA Scientific Session, Anaheim (916) 443-3382, Ext. 4470
April 13-17 International Dental Show, Cologne, Germany, http://www.koelnmesse.de/ids
Aug. 20-22 CDA Scientific Session, San Francisco (916) 443-3382, Ext. 4470
Sept. 17-18 Society for Advanced Dentistry Annual Meeting, New Orleans (317) 290-2613
To have a meeting included on this list, please send the information to Upcoming Meetings, CDA Journal, P.O. Box 13749, Sacramento, CA 95853 or fax the information to (916) 443-3382.