(Press-News.org) BOSTON (April 3, 2013) — Researchers from Tufts University School of Dental Medicine have discovered a statistical association between the injection of local dental anesthesia given to children ages two to six and evidence of missing lower wisdom teeth. The results of this epidemiological study, published in the April issue of The Journal of the American Dental Association, suggest that injecting anesthesia into the gums of young children may interrupt the development of the lower wisdom tooth.
"It is intriguing to think that something as routine as local anesthesia could stop wisdom teeth from developing. This is the first study in humans showing an association between a routinely- administered, minimally-invasive clinical procedure and arrested third molar growth," said corresponding author, Anthony R. Silvestri, D.M.D., clinical professor in the department of prosthodontics and operative dentistry at Tufts University School of Dental Medicine.
Wisdom teeth are potentially vulnerable to injury because their development – unlike all other teeth – does not begin until well after birth. Between two and six years of age, wisdom tooth (third molar) buds begin to develop in the back four corners of the mouth, and typically emerge in the late teens or early adulthood. Not everyone develops wisdom teeth, but for those who do, the teeth often become impacted or problematic.
The American Association of Oral and Maxillofacial Surgeons reports that nine out of 10 people will have at least one impacted wisdom tooth, which can cause bad breath, pain, and/or infection. For this reason, many dentists recommend surgery to remove wisdom teeth to prevent disease or infection.
A developing wisdom tooth, called a bud, is vulnerable to injury for a relatively long time because it is tiny, not covered by bone, and only covered by a thin layer of soft tissue. When a tooth bud first forms, it is no bigger than the diameter of the dental needle itself. The soft tissue surrounding the budding tooth is close to where a needle penetrates when routine dental anesthesia is injected in the lower jaw, for example when treating cavities.
Using the Tufts digital dental record system, the researchers identified records of patients who had received treatment in the Tufts pediatric dental clinic between the ages of two and six and who also had a dental x-ray taken three or more years after initial treatment in the clinic. They eliminated records with confounding factors, such as delayed dental development, and analyzed a total of 439 sites where wisdom teeth could develop in the lower jaw, from 220 patient records.
Group one, the control group (376 sites), contained x-rays of patients who had not received anesthesia on the lower jaw where wisdom teeth could develop. Group two, the comparison group (63 sites), contained x-rays from patients who had received anesthesia.
In the control group, 1.9% of the sites did not have x-ray evidence of wisdom tooth buds. In contrast, 7.9% of the sites in the comparison group – those who had received anesthesia – did not have tooth buds. The comparison group was 4.35 times more likely to have missing wisdom tooth buds than the control group.
"The incidence of missing wisdom teeth was significantly higher in the group that had received dental anesthesia; statistical evidence suggests that this did not happen by chance alone. We hope our findings stimulate research using larger sample sizes and longer periods of observation to confirm our findings and help better understand how wisdom teeth can be stopped from developing," Silvestri continued. "Dentists have been giving local anesthesia to children for nearly 100 years and may have been preventing wisdom teeth from forming without even knowing it. Our findings give hope that a procedure preventing third molar growth can be developed."
Silvestri has previously published preliminary research on third molar tooth development, showing that third molars can be stopped from developing when non- or minimally-invasive techniques are applied to tooth buds.
###
Additional authors of the study are Gerald (Jerry) Swee, D.M.D., M.S., clinical instructor in the department of pediatric dentistry; Matthew Finkelman, Ph.D., assistant professor; Alfred Rich, D.M.D., M.D.S., clinical associate professor in the department of pediatric dentistry; Stanley Alexander, D.M.D., chair and professor of the department of pediatric dentistry; Cheen Loo, B.D.S., M.P.H., Ph.D., D.M.D., associate professor in the department of pediatric dentistry, all of Tufts University School of Dental Medicine.
No external funding supported this research.
Swee J, Silvestri AR, Finkelman MD, Rich AP, Alexander SA, Loo CY. 2013. Inferior Alveolar Nerve Block and Third-Molar Agenesis: A Retrospective Clinical Study. The Journal of the American Dental Association, 144(4), 389-395.
About Tufts University School of Dental Medicine
Founded in 1868, Tufts University School of Dental Medicine (TUSDM) is committed to leadership in education, patient care, research, and community service. Students obtain an interdisciplinary education, integrated with medicine, with access to training in dental specialties. Clinics managed at TUSDM provide quality comprehensive care to more than 18,000 diverse individuals annually, including those requiring special needs. Nationally and internationally, the School promotes health and educational programs and researches new procedures, materials and technologies to improve oral health.
If you are a member of the media interested in learning more about this topic, or speaking with a faculty member at Tufts University School of Dental Medicine or another Tufts health sciences researcher, please contact Siobhan Gallagher at 617-636-6586.
Dental anesthesia may interrupt development of wisdom teeth in children
2013-04-03
ELSE PRESS RELEASES FROM THIS DATE:
Urinary tract infections 29 times more likely in schizophrenia relapse
2013-04-03
AUGUSTA, Ga. – Schizophrenia patients experiencing relapse are 29 times more likely than healthy individuals to have a urinary tract infection, researchers report.
Urinary tract infections, which can cause painful and frequent urination, are common but patients hospitalized for schizophrenia are even more likely to have a UTI than healthy individuals or even others whose illness is under control, said Dr. Brian J. Miller, psychiatrist and schizophrenia expert at the Medical College of Georgia at Georgia Regents University.
The study comparing UTI rates in 57 relapsed ...
Choosing less a form of protection says new study on decision-making
2013-04-03
Toronto – Imagine you have a choice to make.
In one scenario, you'd get $8 and somebody else -- a stranger – would get $8 too. In the other, you'd get $10; the stranger would get $12.
Economists typically assume you'd go for the $10/$12 option because of the belief that people try to maximize their own gains. Choosing the other scenario would just be irrational.
But new research conducted in collaboration with a professor at the University of Toronto's Rotman School of Management shows that if a person is feeling threatened, or concerned with their status, they are ...
Smoking and depressive symptoms in adolescent girls are 'red flag' for postmenopausal osteoporosis
2013-04-03
Philadelphia, PA, April 3, 2013 – Depression, anxiety, and smoking are associated with lower bone mineral density (BMD) in adults, but these factors have not previously been studied during adolescence, when more than 50% of bone accrual occurs. This longitudinal preliminary study is the first to demonstrate that smoking and depressive symptoms in adolescent girls have a negative impact on adolescent bone accrual and may become a red flag for a future constrained by low bone mass or osteoporosis and higher fracture rates in postmenopausal years. The study is published in ...
Study finds ionic thrusters generate efficient propulsion in air
2013-04-03
CAMBRIDGE, MA -- When a current passes between two electrodes — one thinner than the other — it creates a wind in the air between. If enough voltage is applied, the resulting wind can produce a thrust without the help of motors or fuel.
This phenomenon, called electrohydrodynamic thrust — or, more colloquially, "ionic wind" — was first identified in the 1960s. Since then, ionic wind has largely been limited to science-fair projects and basement experiments; hobbyists have posted hundreds of how-to videos on building "ionocrafts" — lightweight vehicles made of balsa wood, ...
Diversity programs give illusion of corporate fairness, study shows
2013-04-03
Diversity training programs lead people to believe that work environments are fair even when given evidence of hiring, promotion or salary inequities, according to new findings by psychologists at the University of Washington and other universities.
The study also revealed that participants, all of whom were white, were less likely to take discrimination complaints seriously against companies who had diversity programs.
Workplace diversity programs are usually developed by human resource departments to foster a more inclusive environment for employees, but aren't typically ...
Invasive crabs help Cape Cod marshes
2013-04-03
PROVIDENCE, R.I. [Brown University] — Long vilified, invasive species can sometimes become an ecosystem asset. New Brown University research published online in the journal Ecology reports exactly such a situation in the distressed salt marshes of Cape Cod. There, the invasive green crab Carcinus maenas is helping to restore the marsh by driving away the Sesarma reticulatum crabs that have been depleting the marsh grasses.
The observations and experiments of the research show that the green crab has filled the void left by the decline of native predators of sesarma crabs, ...
New relief for gynecological disorders
2013-04-03
The creation of new blood vessels in the body, called "angiogenesis," is usually discussed in connection with healing wounds and tumors. But it's also an ongoing process in the female reproductive tract, where the growth and breaking of blood vessels is a normal part of the menstrual cycle. But abnormal growth of blood vessels can have painful consequences and resultant pathologies.
Now, Prof. Ruth Shalgi and research associate Dr. Dana Chuderland of Tel Aviv University's Sackler Faculty of Medicine have found a potential treatment for this abnormal growth in a potent ...
Gender bias found in how scholars review scientific studies
2013-04-03
COLUMBUS, Ohio – A scientist's gender can have a big impact on how other researchers perceive his or her work, according to a new study.
Young scholars rated publications supposedly written by male scientists as higher quality than identical work identified with female authors.
The research found that graduate students in communication -- both men and women -- showed significant bias against study abstracts they read whose authors had female names like "Brenda Collins" or "Melissa Jordan."
These students gave higher ratings to the exact same abstracts when the authors ...
Breakthrough cancer-killing treatment has no side-effects
2013-04-03
Cancer painfully ends more than 500,000 lives in the United States each year, according to the Centers for Disease Control and Prevention. The scientific crusade against cancer recently achieved a victory under the leadership of University of Missouri Curators' Professor M. Frederick Hawthorne. Hawthorne's team has developed a new form of radiation therapy that successfully put cancer into remission in mice. This innovative treatment produced none of the harmful side-effects of conventional chemo and radiation cancer therapies. Clinical trials in humans could begin soon ...
Study: Environmental policies matter for growing megacities
2013-04-03
WEST LAFAYETTE, Ind. – A new study shows clean-air regulations have dramatically reduced acid rain in the United States, Europe, Japan and South Korea over the past 30 years, but the opposite is true in fast-growing East Asian megacities, possibly due to lax antipollution rules or lack of enforcement.
The U.S. Clean Air Act began requiring regulatory controls for vehicle emissions in the 1970s, and 1990 amendments addressed issues including acid rain. Similar steps in the European Union, Japan and South Korea over the past three decades have reduced nitrate and sulfate ...