Tuesday, August 30, 2011

Implant Prosthesis Offers an Improvement Over Dentures



As the number of older adults increases, more people are facing a reduced quality of life because of tooth loss. Edentulism is common among the elderly, and one survey estimates that 37 million Americans will need dentures by 2020. With this increasing demand comes an increasing need to offer a better solution.

An article in the current issue of the Journal of Oral Implantology reports on an alternative treatment to dentures. The “All-on-Four” therapy uses four implants to support a fixed prosthesis, and the patient’s new teeth can be put in place the day of surgery.

When compared with patients who have received implant therapy, those with dentures have shown only a marginal improvement in quality of life, according to clinical studies. These patients report pain, discomfort, poor stability, and difficulty eating. Dental clinicians see the need to offer replacements for natural teeth that allow greater satisfaction and improved quality of life for their patients.

The All-on-Four treatment maximizes the use of available bone and allows immediate functionality. Four implants are placed—two near the front and two near the back of the dental area. These support a fixed, full-arch prosthesis that is put in place the same day as the surgery. The success of this therapy is judged not only by its comfort and usability for the patient, but also by its longevity.

The authors evaluated the survival of the All-in-Four treatment for a 29-month period using the NobelActive implant from Sweden’s Nobel Biocare. This implant features a tapered body and variable thread design. Other All-on-Four implant designs have reported high survival rates between 92 percent and 100 percent.

In this study, 165 patients, with a mean age of 59 years, received 708 implants. No significant difference was found between the survival rates of implants in the maxilla and mandible jaws. Overall, the survival rate was 99.6 percent, with only three implants failing.

Full text of the article,
“The All-on-Four Immediate Function Treatment Concept With NobelActive Implants: A Retrospective Study,”
Journal of Oral Implantology, Vol. 37, No. 5, 2011, is available at http://allenpress.com/publications/journals/orim

About Journal of Oral Implantology
The Journal of Oral Implantology is the official publication of the American Academy of Implant Dentistry and of the American Academy of Implant Prosthodontics. It is dedicated to providing valuable information to general dentists, oral surgeons, prosthodontists, periodontists, scientists, clinicians, laboratory owners and technicians, manufacturers, and educators. The JOI distinguishes itself as the first and oldest journal in the world devoted exclusively to implant dentistry. For more information about the journal or society, please visit: http://www.joionline.org


Tuesday, August 23, 2011

Filling without drilling



Researchers at the University of Leeds have discovered a pain-free way of tackling dental decay that reverses the damage of acid attack and re-builds teeth as new.

The pioneering treatment promises to transform the approach to filling teeth forever.

Tooth decay begins when acid produced by bacteria in plaque dissolves the mineral in the teeth, causing microscopic holes or 'pores' to form. As the decay process progresses these micro-pores increase in size and number. Eventually the damaged tooth may have to be drilled and filled to prevent toothache, or even removed.

The very thought of drilling puts many people off going to see their dentist, whether or not they actually need treatment. This tendency to miss check-ups and ignore niggling aches and pains means that existing problems get worse and early signs of decay in other teeth are overlooked.

It's a vicious cycle, but one that can be broken, according to researchers at the University of Leeds who have developed a revolutionary new way to treat the first signs of tooth decay. Their solution is to arm dentists with a peptide-based fluid that is literally painted onto the tooth's surface. The peptide technology is based on knowledge of how the tooth forms in the first place and stimulates regeneration of the tooth defect.

"This may sound too good to be true, but we are essentially helping acid-damaged teeth to regenerate themselves. It is a totally natural non-surgical repair process and is entirely pain-free too," said Professor Jennifer Kirkham, from the University of Leeds Dental Institute, who has led development of the new technique.

The 'magic' fluid was designed by researchers in the University of Leeds' School of Chemistry, led by Dr Amalia Aggeli. It contains a peptide known as P 11-4 that - under certain conditions - will assemble together into fibres. In practice, this means that when applied to the tooth, the fluid seeps into the micro-pores caused by acid attack and then spontaneously forms a gel. This gel then provides a 'scaffold' or framework that attracts calcium and regenerates the tooth's mineral from within, providing a natural and pain-free repair.

The technique was recently taken out of the laboratory and tested on a small group of adults whose dentist had spotted the initial signs of tooth decay. The results from this small trial have shown that P 11-4 can indeed reverse the damage and regenerate the tooth tissue.

"The results of our tests so far are extremely promising," said Professor Paul Brunton, who is overseeing the patient testing at the University of Leeds Dental Institute. "If these results can be repeated on a larger patient group, then I have no doubt whatsoever that in two to three years time this technique will be available for dentists to use in their daily practice."

"The main reason that people don't go to the dentist regularly is fear. If we can offer a treatment that is completely non-invasive, that doesn't involve a mechanical drill, then we can change that perceived link between dental treatment and pain. This really is more than filling without drilling, this is a novel approach that enables the patients to keep their natural teeth!"

Sports Dental Injuries Are No Laughing Matter


Ω

The crunch of helmets as players tangle for a loose football, the swoosh of the net as an outside jumper is made and the crack of the bat as a guaranteed double sails into right center field are awesome sounds to sports fans but for dentists, they’re reminders that a player is just one misstep away from a dental injury.

“Basketball and baseball are the two biggest mouth-injuring sports,” says Stephen Mitchell, D.M.D., associate professor in the UAB Department of Pediatric Dentistry. “And the most common injuries we see are broken, displaced or knocked out teeth, and broken jaws.”

According to a report by the U.S. Surgeon General, craniofacial injuries sustained during sporting activities are a major source of nonfatal injury and disability in children and adults, accounting for up to one-third of all sports injuries. The National Youth Sports Safety Foundation estimates that more than 3 million teeth will be knocked out in youth sporting activities this year.

The increasing participation of girls and young women in competitive sports means that they, just like their male counterparts, should know the risks of dental injuries and use additional protective gear as appropriate, Mitchell says.
Mitchell says mouth guards and helmets with face protectors are the best way for kids to avoid dental injuries while playing sports.

“If the child has a full set of permanent teeth then a custom guard can be made that will provide protection but be small enough to make it easy to communicate with teammates,” Mitchell says. “But if they still have some of their baby teeth, a custom guard is a waste of money. Parents will be better off going to the store and buying one of the guards that can be boiled and molded to their child’s mouth.”

So what should you do if despite your best preventive efforts your child still hurts his or her teeth or jaw?

If a tooth is broken or cracked, see a dentist within 24 hours, Mitchell says. If a tooth or teeth have been displaced or knocked out, Mitchell says, take the child immediately to the emergency room and to try to preserve the tooth.

“A tooth that has been knocked out needs to be back in the mouth within 30 minutes for the best chance of long-term survival,” Mitchell says. He offers these tips for preserving the tooth, which can even help past the ideal 30-minute window:
• Avoid touching the root because it can be damaged easily.
• If the tooth is dirty, hold it by the upper part and rinse it off with milk until most of the dirt is washed away. If you don't have milk, don’t clean it. Wiping it off may cause more damage.
• If your child is old enough not to swallow it, try to gently put the tooth back in its socket for the best chance of preservation.
• If you can’t get it back in the socket, put it in a cup of milk and head for the dentist or emergency room.
“We tell people to put the tooth in milk because the cells around the root are still alive after it is knocked out and milk can provide nutrients to the cells to help keep them alive,” Mitchell adds. “Do not put the tooth in water. It can cause the cells to burst and makes saving the tooth much less likely.”
Jaw injuries may be much less obvious than a broken or knocked-out tooth but they are no less serious, Mitchell says. If a child falls hard enough to cut their chin, or takes an especially hard hit, it could easily cause breaks in the jaw. In an injury such as this, a child should be seen by a doctor within 24 hours.
No matter the injury, Mitchell says caring properly for the mouth afterward is key to successful healing.
“Following an injury a child’s mouth will be sore and they will want to do everything they can to make it not hurt. But, continuing to brush their teeth and practice good oral hygiene is extremely important,” he says. “It is the same as keeping any other wound clean, the cleaner the mouth is kept, the better it heals.”Home
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Sports Dental Injuries Are No Laughing Matter
Released: 8/22/2011 5:30 PM EDT
Source: University of Alabama at Birmingham
Newswise — BIRMINGHAM, Ala. – The crunch of helmets as players tangle for a loose football, the swoosh of the net as an outside jumper is made and the crack of the bat as a guaranteed double sails into right center field are awesome sounds to sports fans but for dentists, they’re reminders that a player is just one misstep away from a dental injury.
“Basketball and baseball are the two biggest mouth-injuring sports,” says Stephen Mitchell, D.M.D., associate professor in the UAB Department of Pediatric Dentistry. “And the most common injuries we see are broken, displaced or knocked out teeth, and broken jaws.”
According to a report by the U.S. Surgeon General, craniofacial injuries sustained during sporting activities are a major source of nonfatal injury and disability in children and adults, accounting for up to one-third of all sports injuries. The National Youth Sports Safety Foundation estimates that more than 3 million teeth will be knocked out in youth sporting activities this year.
The increasing participation of girls and young women in competitive sports means that they, just like their male counterparts, should know the risks of dental injuries and use additional protective gear as appropriate, Mitchell says.
Mitchell says mouth guards and helmets with face protectors are the best way for kids to avoid dental injuries while playing sports.
“If the child has a full set of permanent teeth then a custom guard can be made that will provide protection but be small enough to make it easy to communicate with teammates,” Mitchell says. “But if they still have some of their baby teeth, a custom guard is a waste of money. Parents will be better off going to the store and buying one of the guards that can be boiled and molded to their child’s mouth.”
So what should you do if despite your best preventive efforts your child still hurts his or her teeth or jaw?
If a tooth is broken or cracked, see a dentist within 24 hours, Mitchell says. If a tooth or teeth have been displaced or knocked out, Mitchell says, take the child immediately to the emergency room and to try to preserve the tooth.
“A tooth that has been knocked out needs to be back in the mouth within 30 minutes for the best chance of long-term survival,” Mitchell says. He offers these tips for preserving the tooth, which can even help past the ideal 30-minute window:
• Avoid touching the root because it can be damaged easily.
• If the tooth is dirty, hold it by the upper part and rinse it off with milk until most of the dirt is washed away. If you don't have milk, don’t clean it. Wiping it off may cause more damage.
• If your child is old enough not to swallow it, try to gently put the tooth back in its socket for the best chance of preservation.
• If you can’t get it back in the socket, put it in a cup of milk and head for the dentist or emergency room.

“We tell people to put the tooth in milk because the cells around the root are still alive after it is knocked out and milk can provide nutrients to the cells to help keep them alive,” Mitchell adds. “Do not put the tooth in water. It can cause the cells to burst and makes saving the tooth much less likely.”

Jaw injuries may be much less obvious than a broken or knocked-out tooth but they are no less serious, Mitchell says. If a child falls hard enough to cut their chin, or takes an especially hard hit, it could easily cause breaks in the jaw. In an injury such as this, a child should be seen by a doctor within 24 hours.
No matter the injury, Mitchell says caring properly for the mouth afterward is key to successful healing.

“Following an injury a child’s mouth will be sore and they will want to do everything they can to make it not hurt. But, continuing to brush their teeth and practice good oral hygiene is extremely important,” he says. “It is the same as keeping any other wound clean, the cleaner the mouth is kept, the better it heals.”

Thursday, August 18, 2011

Gaps in dental care coverage among retirees may lead to their delaying or stopping use of dental care


Retirees may be at risk for sporadic dental care or even stopping use due to dental coverage transitions and status of insurance, reports a new study released today in the American Journal of Public Health.


Researchers examined dental care utilization transition dynamics in the context of changing dental coverage status among a population around the age of retirement. They used data from the Health and Retirement Study (HRS) to assess the characteristics of persons aged 51 years and older based on whether they had maintained or changed their dental care use status between the 2004 and 2006 waves of HRS. They were particularly concerned with discovering how changes in dental coverage and changes in retirement status affected the relative likelihood of having irregular dental care utilization patterns.

The sample consisted of 16,345 individuals interviewed in both the 2004 and 2006 HRS, representing 74,047,165 members of the community-based population who were aged 51 years and older at the time of the 2004 interview. They found that Americans aged 51 years and older who lost dental coverage between the 2004 and 2006 survey periods were more likely to stop dental care use between periods, than those without coverage in both periods. Those who gained coverage were more likely to start dental care use between periods, than those without coverage in both periods.

The study’s authors said, “Although we were only able to look at a short time horizon with the HRS data and therefore do not know the longer-term use patterns of those who lose coverage around retirement age, even short-term lapses in preventive coverage can result in more invasive and costly procedures in the future. For retirees on fixed incomes, the high cost of dental procedures could have important financial consequences, and the delay of care could lead to worse overall health status and affect more than only dental costs.”

[From: “The Influence of Changes in Dental Care Coverage on Dental Care Utilization Among Retirees and Near-Retirees in the United States, 2004—2006.” ]

Monday, August 15, 2011

Can oral care for babies prevent future cavities?


Ω

New parents have one more reason to pay attention to the oral health of their toothless babies. A recent University of Illinois study confirms the presence of bacteria associated with early childhood caries (ECC) in infant saliva.

ECC is a virulent form of caries, more commonly known as tooth decay or a cavity. Cavities are the most prevalent infectious disease in U.S. children, according to the Centers for Disease Control and Prevention.

"By the time a child reaches kindergarten, 40 percent have dental cavities," said Kelly Swanson, lead researcher and U of I professor of animal science. "In addition, populations who are of low socioeconomic status, who consume a diet high in sugar, and whose mothers have low education levels are 32 times more likely to have this disease."

Swanson's novel study focused on infants before teeth erupted, compared to most studies focused on children already in preschool or kindergarten – after many children already have dental cavities.

"We now recognize that the "window of infectivity," which was thought to occur between 19 and 33 months of age years ago, really occurs at a much younger age," he said. "Minimizing snacks and drinks with fermentable sugars and wiping the gums of babies without teeth, as suggested by the American Academy of Pediatric Dentistry, are important practices for new parents to follow to help prevent future cavities."

In addition, his team used high-throughput molecular techniques to characterize the entire community of oral microbiota, rather than focusing on identification of a few individual bacteria.

"Improved DNA technologies allow us to examine the whole population of bacteria, which gives us a more holistic perspective," Swanson said. "Like many other diseases, dental cavities are a result of many bacteria in a community, not just one pathogen."

Through 454 pyrosequencing, researchers learned that the oral bacterial community in infants without teeth was much more diverse than expected and identified hundreds of species. This demonstration that many members of the bacterial community that cause biofilm formation or are associated with ECC are already present in infant saliva justifies more research on the evolution of the infant oral bacterial community, Swanson said.

Could manipulating the bacterial community in infants before tooth eruption help prevent this disease in the future?

"The soft tissues in the mouth appear to serve as reservoirs for potential pathogens prior to tooth eruption," he said. "We want to characterize the microbial evolution that occurs in the oral cavity between birth and tooth eruption, as teeth erupt, and as dietary changes occur such as breastfeeding vs. formula feeding, liquid to solid food, and changes in nutrient profile."

Swanson said educating parents-to-be on oral hygiene and dietary habits is the most important strategy for prevention of dental cavities.

Thursday, August 11, 2011

Dentists, Pharmacists Raise Awareness of Medication-Induced Dry Mouth



Leading dental and pharmacy organizations are teaming up to promote oral health and raise public awareness of dry mouth, a side effect commonly caused by taking prescription and over-the-counter medications. More than 500 medications can contribute to oral dryness, including antihistamines (for allergy or asthma), antihypertensive medications (for blood pressure), decongestants, pain medications, diuretics and antidepressants. In its most severe form, dry mouth can lead to extensive tooth decay, mouth sores and oral infections, particularly among the elderly.

Nearly half of all Americans regularly take at least one prescription medication daily, including many that produce dry mouth, and more than 90 percent of adults over age 65 do the same. Because older adults frequently use one or more of these medications, they are considered at significantly higher risk of experiencing dry mouth.

The American Dental Association (ADA), Academy of General Dentistry (AGD), American Academy of Periodontology (AAP) and the American Pharmacists Association (APhA) are collaborating to expand awareness of the impact of medications on dry mouth, a condition known to health professionals as xerostomia.

With regular saliva production, your teeth are constantly bathed in a mineral-rich solution that helps keep your teeth strong and resistant to decay. While saliva is essential for maintaining oral health and quality of life, at least 25 million Americans have inadequate salivary flow or composition, and lack the cleansing and protective functions provided by this important fluid.

“Each day, a healthy adult normally produces around one-and-a-half liters of saliva, making it easier to talk, swallow, taste, digest food and perform other important functions that often go unnoticed,” notes Dr. Fares Elias, president, Academy of General Dentistry. “Those not producing adequate saliva may experience some common symptoms of dry mouth.”

Signs and symptoms

At some point, most people will experience the short-term sensation of oral dryness because of nervousness, stress or just being upset. This is normal and does not have any long-term consequences. But chronic cases of dry mouth persist for longer periods of time. Common symptoms include trouble eating, speaking and chewing, burning sensations, or a frequent need to sip water while eating.

“Dry mouth becomes a problem when symptoms occur all or most of the time and can cause serious problems for your oral health,” explains Dr. Matthew Messina, ADA consumer advisor. “Drying irritates the soft tissues in the mouth, which can make them inflamed and more susceptible to infection.”

According to Dr. Messina, who practices general dentistry in the Cleveland area, without the cleansing and shielding effects of adequate saliva flow, tooth decay and periodontal (gum) disease become much more common. “Constant dryness and the lack of protection provided by saliva may contribute to bad breath. Dry mouth can make full dentures become less comfortable to wear because there is no thin film of saliva to help them adhere properly to oral tissues,” he adds. “Insufficient saliva can also result in painful denture sores, dry and cracked lips, and increased risks of oral infection.”

Common causes


Once considered an inevitable part of aging, dry mouth is now commonly associated with certain medications and autoimmune conditions such as Sjogren’s syndrome. Both of these can reduce salivary production or alter its composition, but experts agree that the primary cause of dry mouth is the use of medications.
Radiation treatment for head and neck cancer is also an important cause of severe dry mouth. The treatment can produce significant damage to the salivary glands, resulting in diminished saliva production and extreme dry mouth in many cases.
“Saliva plays an important role in maintaining oral health,” says Dr. Donald Clem, president of the American Academy of Periodontology. “With decreased saliva flow, we can see an increase in plaque accumulation and the incidence and severity of periodontal diseases.”

How to relieve dry mouth

Individuals with dry mouth should have regular dental checkups for evaluation and treatment. “Be sure to carry an up-to-date medication list at all times, and tell your dentist what medications you are taking and other information about your health at each appointment," advises Mr. Thomas Menighan, executive vice president and Chief Executive Officer, American Pharmacists Association. "In some cases, a different medication can be provided or your dosage modified to alleviate dry mouth symptoms. Talk to your pharmacist if you have any questions regarding your medication.”

Increasing fluid intake, chewing sugarless gum, taking frequent sips of water or sucking on ice chips can also help relieve dry mouth symptoms. Avoiding tobacco and intake of caffeine, alcohol and carbonated beverages may also help those with the condition. Your dentist may recommend using saliva substitutes or oral moisturizers to keep your mouth wet. Your local pharmacist is also a helpful source for information on products to help you manage dry mouth.

Tuesday, August 9, 2011

Ultraviolet-B and Vitamin D Reduce Risk of Dental Caries

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Large geographical variations in dental health and tooth loss among U.S. adolescents and young adults have been reported since the mid-1800s. The first study finding a north-south gradient in dental caries was a report of men rejected from the draft for the Civil War for lost teeth, from 8 per 1000 men in Kentucky to 25 in New England.

Studies by Clarence Mills and Bion East in the 1930s first linked the geographical variation in prevalence to sunlight exposure. They used data for adolescent males aged between 12 and 14 years from a cross-sectional survey in 1933–1934. East later found that dental caries were inversely related to mean hours of sunlight/year, with those living in the sunny west (3000 hours of sunlight/year) having half as many carious lesions as those in the much less sunny northeast (<2200 hours of sunlight/year).
Several studies conducted in Oregon in the 1950s noted that dental caries prevalence was lower in the sunnier regions of the state than in the cloudy regions, a finding that persisted after considering other factors that affect dental caries rates. The mechanism was attributed to vitamin D through its effects on calcium metabolism.

There were also several studies reported on vitamin D and dental caries in the 1920s and 1930s. May Mellanby and coworkers in Sheffield, England, did studies on the role of vitamin D on teeth in the 1920s. The first experiments were with dogs, where it was found that vitamin D stimulated the calcification of teeth. Subsequently, they studied the effect of vitamin D on dental caries in children, finding a beneficial effect. Additional studies were conducted on children in New York regarding dental caries with respect to season, artificial ultraviolet-B (UVB) irradiance, and oral intake of vitamin D with the finding that it took 800 IU/d to prevent caries effectively.
The mechanism whereby UVB reduces risk of dental caries is through production of vitamin D, followed by induction of cathelicidin, which attacks oral bacteria linked to dental caries. Cathelicidin is well known to fight bacterial infections, with findings reported for several bacterial infections including pneumonia, sepsis, and tuberculosis. Several recent papers reported that cathelicidin reduces the risk of caries, but did not link cathelicidin to vitamin D.

Serum 25-hydroxyvitamin D concentrations around 30-40 ng/ml (75-100 nmol/L) should significantly reduce the formation of dental caries. (The average white American has a level near 25 ng/ml, while the average black American has a level near 16 ng/ml.) To obtain these levels, oral intake of 1000-4000 IU/d of vitamin D3 or 15-20 minutes in the sun near solar noon in summer with 20-30% body surface area exposed is suggested.
Good dental health also involves a healthy diet low in sugar, regular tooth brushing, and regular dental checkups.

Use of vitamin D appears to be a better option for reducing dental caries than fluoridation of community water supplies as there are many additional health benefits of vitamin D and a number of adverse effects of water fluoridation such as fluorosis (mottling) of teeth and bones.

The paper is published online with open access:
Grant WB. A review of the role of solar ultraviolet-B irradiance and vitamin D in reducing risk of dental caries. Dermato-Endocrinology, 3:3, 1-6; July/August/September 2011; epub

Wednesday, August 3, 2011

Gum Disease Can Increase the Time It Takes to Become Pregnant

Ω

Professor Roger Hart told the annual meeting of the European Society of Human Reproduction and Embryology that the negative effect of gum disease on conception was of the same order of magnitude as the effect of obesity.

Periodontal (gum) disease is a chronic, infectious and inflammatory disease of the gums and supporting tissues. It is caused by the normal bacteria that exist in everyone's mouths, which, if unchecked, can create inflammation around the tooth; the gum starts to pull away from the tooth, creating spaces (periodontal pockets) that become infected. The inflammation sets off a cascade of tissue-destructive events that can pass into the circulation. As a result, periodontal disease has been associated with heart disease, type 2 diabetes, respiratory and kidney disease, and problems in pregnancy such as miscarriage and premature birth. Around 10% of the population is believed to have severe periodontal disease. Regular brushing and flossing of teeth is the best way of preventing it.

Prof Hart, who is Professor of Reproductive Medicine at the University of Western Australia (Perth, Australia) and Medical Director of Fertility Specialists of Western Australia, said: "Until now, there have been no published studies that investigate whether gum disease can affect a woman's chance of conceiving, so this is the first report to suggest that gum disease might be one of several factors that could be modified to improve the chances of a pregnancy."

The researchers followed a group 3737 pregnant women, who were taking part in a Western Australian study called the SMILE study, and they analysed information on pregnancy planning and pregnancy outcomes for 3416 of them.

They found that women with gum disease took an average of just over seven months to become pregnant -- two months longer than the average of five months that it took women without gum disease to conceive.

In addition, non-Caucasian women with gum disease were more likely to take over a year to become pregnant compared to those without gum disease: their increased risk of later conception was 13.9% compared to 6.2% for women without gum disease. Caucasian women with gum disease also tended to take longer to conceive than those who were disease-free but the difference was not statistically significant (8.6% of Caucasian women with gum disease took over one year to conceive and 6.2% of women with gum disease).

Information on time to conception was available for 1,956 women, and of, these, 146 women took longer than 12 months to conceive -- an indicator of impaired fertility. They were more likely to be older, non-Caucasian, to smoke and to have a body mass index over 25 kg/m2. Out of the 3416 women, 1014 (26%) had periodontal disease.

Prof Hart said: "Our data suggest that the presence of periodontal disease is a modifiable risk factor, which can increase a woman's time to conception, particularly for non-Caucasians. It exerts a negative influence on fertility that is of the same order of magnitude as obesity. This study also confirms other, known negative influences upon time to conception for a woman; these include being over 35 years of age, being overweight or obese, and being a smoker. There was no correlation between the time it took to become pregnant and the socio-economic status of the woman.

"All women about to plan for a family should be encouraged to see their general practitioner to ensure that they are as healthy as possible before trying to conceive and so that they can be given appropriate lifestyle advice with respect to weight loss, diet and assistance with stopping smoking and drinking, plus the commencement of folic acid supplements. Additionally, it now appears that all women should also be encouraged to see their dentist to have any gum disease treated before trying to conceive. It is easily treated, usually involving no more than four dental visits.

"The SMILE study was one of the three largest randomised controlled trials performed in Western Australia. It showed conclusively that although treatment of periodontal disease does not prevent pre-term birth in any ethnic group, the treatment itself does not have any harmful effect on the mother or fetus during pregnancy."

Prof Hart said that the reason why pregnancies in non-Caucasian women were more affected by gum disease could be because these women appeared to have a higher level of inflammatory response to the condition.