Research Shows No Fluoride-Bone Fracture Link

For more than a half century, fluoridation of public water supplies has been a flash point for voluminous debate. Fluoride opponents have continued their passionate harangues even as scientific evidence has piled up in support of the chemical’s safety and efficacy.

Studies continue to be completed showing the hollow nature of shouted claims that fluoride causes all manner of harm. What those studies generally indicate is that fluoride helps ensure improved dental health and that it is especially important for children who do not have the benefit of access to dental care.

An argument currently in vogue with fluoride opponents is that people who ingest fluoridated drinking water are more susceptible to bone fractures as they age. And while they are pointing to studies as their evidence, those "studies" are not standing up to the standards of true science.

The most frequent finding of legitimate studies focusing on the relationship between ingestion of fluoridated water and bone fractures is that there is no connection.

For example, a case-control study’s results in England were reported comparing about 500 men and women aged 50 and older with hip fractures to a similar number without the fractures. The results, published in the Jan. 22 issue of The Lancet, showed the chance of fracturing a hip was the same for those who drank water containing fluoride at concentrations of about 1 part per million as for those whose water contained less fluoride.

In another study, 7,500 Chinese in 60 villages were followed for six years to determine the relationship between bone fracture prevalence and long-term natural fluoride exposure in a range of concentrations bracketing 1 part per million.

Barry P. Katz, PhD, director of Indiana University’s Division of Biostatistics in the Department of Medicine says he got involved in the middle of the study in 1997 to determine fluoride’s effect on bone fracture.

"The basic data show a public health benefit of the lowest fracture rate at between 1 and 1.06 parts per million, which coincides with the level of water fluoridation in the United States," Katz says. "We also looked specifically at hip fractures. We had fewer hip fractures than we had hoped for statistical analysis, but the results seem to support the other data in our study. The results of both parts of the study seem to support the study in England."

Katz says that the study in China was significant because it centered on elderly people who had lived their entire lives in rural farming towns, so the study involved lifelong fluoride exposure.

In a third recent study, more than 7,000 women in the United States were followed for seven years to compare bone fractures in those exposed to water fluoridation for the past 20 years compared to women with no water fluoridation exposure.

Kathy Phipps, who holds a doctorate in public health, was the principal investigator. She is an associate professor at Oregon Health Sciences University in Portland, and has been doing research on the impact of fluoride on osteoporosis and fracture rates for about 10 years.

"We found that there was no increase in hip or vertebral fractures in women exposed to fluoridated water," Phipps says. "In fact, fluoridation in this study had a slightly protective effect."

Phipps said her study was the largest on community water fluoridation and fractures to date. Her research paper was recently accepted for publication in the British Medical Journal.

Robert Selwitz, DDS, MPH, senior dental epidemiologist at the National Institute of Dental and Craniofacial Research Office of Science Policy and Analysis, says some studies that seem to support a link between fluoridation and bone fractures must be regarded skeptically.

"Many studies indicating a relationship between water fluoridation and bone fracture are referring to ecological studies that have inherent weaknesses, since fluoride histories for individuals involved were never obtained," Selwitz says.

Selwitz says there are also many confounders unaccounted for by ecological studies, such as individuals’ estrogen levels or use of estrogen and vitamin D supplements, smoking, occupational exposure, and dietary patterns that might influence differences in bone disease rates in fluoridated and nonfluoridated areas.

Phipps says she controlled for all of the confounding factors.

"And over the last 10 years, we’ve moved from ecologic studies to looking at more individual level studies, which allow for greater control," she says. "Based on our and others’ current high-quality research, community water fluoridation does not increase an individual’s risk of hip fractures."

Selwitz says there is little real evidence linking fluoride and broken bones.

"The sum of the evidence to date appears to indicate that water fluoridation does not increase the risk for bone fracture," he says. "But more research is needed."

Phipps says she believes that the three recent studies allow the scientific community to lay the issue to rest.

"The only population group we haven’t looked at in our country is elderly men, but there’s no reason to assume there would be a different effect on them compared with women," she says.

Protecting the State of Your Estate

By Marios P. Gregoriou

You’ve spent years growing your wealth and building your estate, so it is just good sense to plan to protect your assets and pass them on to your beneficiaries according to your wishes. Here’s how:

* Write a will. If you do not have a will when you die, the law of your state may determine what happens to your estate, your assets, and any minor children. In addition, the state process, usually governed by probate court, is often slow, sometimes expensive, and open to the public.

* Fund a living trust. Follow through if you set up a living trust. Until you transfer ownership of property or assets to it, the trust is not worth any more to you or your beneficiaries than the paper it’s printed on. Unfortunately, many revocable living trusts are set up but remain unfunded.

* Re-title joint-tenancy property. Joint-tenancy-with-right-of-survivorship titling of assets may result in estate planning headaches. Although probate is avoided at the first joint owner’s death, it is not avoided at the death of the survivor, thus only delaying estate taxes. Re-titling assets to a credit shelter trust can help avoid probate and provide estate tax savings.

* Use both spouses’ applicable exclusion amount. Leaving all property and assets to a spouse may avoid estate taxed at the death of the first spouse, but this approach wastes the gift and estate tax credit of the first to die. A credit shelter trust can maximize each spouse’s credit, thus sheltering more assets from estate tax liabilities.

* Re-title ownership of life insurance policies. Most life insurance policies are owned by the insured, causing the policy’s face amount to be included in that person’s estate at his or her death. Policy owners may consider giving policies directly to the beneficiary or transferring the policies to an irrevocable life insurance trust. Either strategy could help reduce estate taxes.

* Choose an appropriate executor. Naming an inexperienced family member as executor could complicate the demanding task of settling your estate. This is especially true at a difficult and emotional time following a death. Look into the benefit of naming a professional organization to follow through with the duties of an executor.

* Organize your paperwork and files. If you do not provide your executors and beneficiaries with all the paperwork or files pertaining to your property, assets, and wishes, improper distribution and management of your estate may result.

* Update your estate plan. Updating your estate plan from time to time is important so that it is implemented exactly according to your wishes. You will want to update your estate plan when there are changes in your family (births, marriages, divorces, deaths, for example); when the value of your estate significantly increases or decreases; when tax laws change; if you move to another state; or if your profession or career changes.

Marios Gregoriou is associate vice president financial adviser with Morgan Stanley Dean Witter in Sacramento. He can be reached by calling (800) 755-8041. This article is published for information purposes and is not an offer or solicitation to sell or buy any securities or commodities. Any particular investment should be analyzed based on its terms and risks as they relate to your circumstances and objectives.

More Evidence Supports Perio-Preterm Birth Link

The more of the mouth affected with periodontal disease, the more likely a woman is to deliver a premature baby, according to an ongoing study of more than 2,000 pregnant women.

The results offer further indications that periodontal disease may be a significant risk factor for preterm births.

Past studies have shown that women with periodontal disease may be up to seven times more likely to deliver a preterm low-birth-weight baby. Preliminary research was recently presented at the American Academy of Periodontology’s Specialty Conference on Periodontal Medicine suggesting that the risk for women who have generalized periodontal disease (affecting at least 30 percent of their mouth) is even higher.

"We were amazed by these findings," said Marjorie Jeffcoat, DMD, the study’s lead researcher and chair of periodontics at the University of Alabama at Birmingham School of Dentistry. However, women with only a couple of sites in their mouths affected by periodontal disease aren’t in the clear. "While there is a definite dose response, the trend for preterm birth was observed in women with as few as two sites with attachment loss," Jeffcoat said.

The women in the study had no other major risk factors for preterm birth.

Doxycycline Enhances Effects of Root Planing on Gum Disease

A recent clinical trial found that subantimicrobial dose doxycycline significantly improved the results of scaling and root planing in the treatment of adult periodontitis.

The study was published in the May 2000 issue of the Journal of Periodontology.

"Data from this study suggest that [subantimicrobial dose doxycycline] may have an important role in the successful long-term management of adult periodontitis," says lead investigator Jack G. Caton, DDS, MS, professor of periodontology at the University of Rochester’s Eastman Dental Center. "These results demonstrate that effective nonsurgical treatment may require a two-pronged approach aimed at both reducing bacterial load through the use of [scaling and root planing] and suppressing the destructive enzymes that are produced in response to bacteria, utilizing [doxycycline]."

Caton and colleagues report that twice-daily adjunctive treatment with 20 mg capsules of doxycycline hyclate yielded a substantial improvement in clinical attachment levels and probing depths compared with scaling and root planing and a placebo capsule.

The multicenter, double-blind clinical trial was conducted at five dental schools: the State University of New York at Buffalo, West Virginia University Medical Center, the University of Florida at Gainesville, the University of Pennsylvania, and the Eastman Dental Center at the University of Rochester.

Study Cites Varied Reasons Children Cry in the Dental Office

A crying child in a dental office can make treatment next to impossible if the child is not calmed down and doesn’t cooperate with the treatment, but the child may not be crying out of fear or pain, write Dan Zadik, DMD, and Benjamin Peretz, DMD, in the January-February 2000 Journal of Dentistry for Children.

While it is easy for children to utilize fear in the dental office as a catchall reason for crying, there may be other explanations for the child’s behavior.

Since children cry for a variety of reasons, dentists should have a wide range of behavior management methods to meet the needs of individual children. The authors refer to H.G. Elsbach’s theory that crying is a mode of expression and should be used as a diagnostic tool. Elsbach classified four types of crying: fear-motivated crying accompanied by hysterical behavior, pain-motivated crying, compensatory-motivated crying, and steady-state siren-like crying.

The authors cite a study involving 104 parents who accompanied their children, ages 2 to 13, for dental treatment at the Department of Pediatric Dentistry at the Hebrew University-Hadassah Faculty of Dental Medicine in Jerusalem. Each child had at least one session for an operative procedure after an initial evaluation. All parents were present in the operatory during treatment.

About 48 percent of the children fully cooperated in previous dental procedures, while 24 percent exhibited limited cooperation and 28 percent were totally uncooperative. The mother accompanied most children (61 percent), while 36 percent came with the father. Four children came with a grandparent.

Findings showed that when a child cried with no evidence of pain, most parents preferred stopping treatment and calming the child before resuming treatment. Most parents also felt they had to assist the operator in calming the child.

One aspect of the study showed that at least some of the children were not fearful or even excited, but either cried to avoid the treatment or had a general tendency to cry. Stopping treatment for these children may serve as a reinforcement to continue crying, and for these children a "matter of fact" approach is the method of choice, the authors write.

Zadik and Peretz stress that dentists should acquire a repertoire of behavioral and cognitive skills to regulate patients who cry. With effective guidance by the dentist, a child can learn to collaborate during the dental experience, they note. The successful completion of treatment, they say, is viewed as a partnership between the dentist and parent. It is, however, important that the dentist inform the parent about the method to be used and receive the parent’s consent.

Family History Leads to Gene Disorder Discovery

The study of a family’s unusual history of missing teeth dating back to 1645 has led researchers at the University of Texas-Houston to identify the responsible gene, reports Lisa Garvin of the University of Texas-Houston Health Science Center Department of Public Affairs

According to an article in the January/February 2000 American Association of Orthodontists Bulletin, a mutation of the gene known as PAX9 is the cause of a rare form of oligodontia in a Houston family.

Study co-author Dr. Monica Goldenberg, an orthodontic resident, noticed a 13-year-old patient was missing 14 permanent teeth. After questioning the mother, Goldenberg learned the patient’s father and two brothers had the same condition. In 43 family members, 21 were found to have missing molars.

DNA samples from affected family members revealed an extra nucleic acid on the PAX9 gene, which disrupted the normal protein sequence and caused the defect. The mutation is dominant, meaning offspring of an affected parent have a 50 percent chance of inheriting the missing-tooth trait, and it appears in every generation.

The study marks the first time a human disorder has been linked to a mutation on PAX9, which is one of a family of nine master genes that regulate organ development.

Others involved in the study and gene analysis were Drs. Rena D’Souza, Marion Messersmith, Parimal Das, David Stockton, and Pragna Patel.

Details of the study are in the Jan. 1, 2000, issue of Nature Genetics magazine, and more details on the description of the family will be published in the Journal of Dental Research.

D’Souza is interested in identifying other families with multiple congenitally missing teeth and can be contacted at (713) 500-4218 or by e-mail at rdsouza@mail.db.uth.tmc.edu .

Disabled Dentists Sought for Study

The Oregon Health Sciences University is conducting a qualitative investigation on the education and practice of dentists with disabilities. OHSU invites such dentists to share the aspects of their education and profession that have been positive and/or negative in relation to their disability.

To participate, contact Jared Schultz, project coordinator, at (503) 232-9154, Ext. 128.

Honors

The American Association of Dental Schools has named Arthur A. Dugoni, DDS, as the third recipient of the AADS Distinguished Service Award. Dugoni is dean of the University of the Pacific School of Dentistry.

Upcoming Meetings

2000

July 26-28 Pacific Northwest Dental Conference, Seattle, www.wsda.org

July 30-Aug. 2 Congress of the International Society for Lasers in Dentistry, Brussels, Belgium, +32 2 648 80 59.

Aug. 14-16 Association of Philippine Orthodontists National Congress, Manila, Philippines, (632) 890-2824

Aug. 30-Sept. 2 Surfaces in Biomaterials 2000, Scottsdale, Ariz., (612) 512-9103, http://www.surfaces.org/00pp.htm

Sept. 15-17 CDA Scientific Session, San Francisco, (916) 443-3382, Ext. 4470

Sept. 17-20 American Academy of Periodontology Annual Meeting, Honolulu, www.perio.org

Oct. 14-18 ADA Annual Session, Chicago, (312) 440-2500

Oct. 19-21 Academy of Surgical Research Annual Meeting (612) 545-1919, http://www.surgicalresearch.org/00sess.htm

Oct. 26-28 American Society for Dental Aesthetics, Millennium International Conference, San Francisco, (800) 454-2732, www.asdatoday.com

Nov. 15-18 American College of Prosthodontics annual session, (312) 573-1260, Ext. 15.

Nov. 29-Dec. 2 FDI World Dental Congress, Paris, http://www.fdi.org.uk/congress/index.htm

2001

April 19-22 CDA Scientific Session, Anaheim, (916) 443-3382, Ext. 4470

May 4-8 Australian Dental Congress, Brisbane, +61 (0) 7 3369 0477

Sept. 14-16 CDA Scientific Session, San Francisco, (916) 443-3382, Ext. 4470

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) 443-2943.