The results of the 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.
Researchers from Tufts University School of Dental Medicine discovered the statistical association between the injection of local dental anesthesia given to children ages two to six and evidence of missing lower wisdom teeth.
Anthony R Silvestri, clinical professor in the department of prosthodontics and operative dentistry, said: ‘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.’
Using the Tufts digital dental record system, the researchers identified records of patients who had received treatment in the Tufts paediatric 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 analysed 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 anaesthesia – did not have tooth buds.
The comparison group was 4.35 times more likely to have missing wisdom tooth buds than the control group.
Professor Silvestri continued: ‘The incidence of missing wisdom teeth was significantly higher in the group that had received dental anaesthesia; 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.
‘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.’