The results of a new study in the Journal of Dental Research (September 2012, Vol. 91:9, 841-846) will help dentists identify which at-risk sites on teeth are likely to become carious if no preventive action is taken, according to the study authors.
Dentists could treat those at-risk sites to at least delay, if not stop, caries from developing, the authors wrote.
The four-year, $3.4 million study, conducted at the Indiana University (IU) School of Dentistry and the University of Puerto Rico and funded by the National Institutes of Health, is believed to be the first extended examination since 1966 of the natural history of dental caries using detailed criteria. A total of 565 children between the ages of 5 and 13 were recruited for the study in 2007. Of these, 338 children completed all examinations. The children were examined at regular intervals for 48 months.
While a lot is known about caries, little is known about the process that leads from early caries lesions to full decay, according to lead author Andrea Ferreira Zandona, DDS, PhD, director of the Graduate Preventive Dentistry Program and an associate professor in the department of preventive and community dentistry at the IU dental school.
Because some caries lesions progress and some don't, identification of at-risk sites is one of the biggest challenges faced by dentists, according to the study authors. To date, the practice has been to wait and watch lesions until they reach the point where the dentists believe a restoration is required, according to Dr. Zandona.
The purpose of the present study was to evaluate whether lesions could be evaluated using the International Caries Detection and Assessment System (ICDAS) to identify with greater predictability which ones were more likely to become cavities.
"What we were trying to see was if we could identify when lesions reach the point that they will become cavities," Dr. Zandona said in a university press release. "Are there some signs we see on teeth that signal when it is progressing towards cavitation? When we see a 1, does it become a 2 and progress to higher scores? What happens when we see a 2? If dentists knew that, they could target prevention at those lesions."
IU researchers developed the ICDAS exam with a small group of international scientists. In the study, examiners used the ICDAS to give lesions a score, ranging from 1 to 6 -- with 1 representing a lesion so small that it was difficult to see and scores greater than 5 indicating what is usually considered a cavity -- and judged whether a lesion was active or not. The lesions were tracked for 48 months, with some registering higher and higher scores until they progressed to cavities.
After analyzing data collected in the study, the researchers concluded that the higher the ICDAS score beyond 1, and after a determination that the caries lesion is active, the greater the probability the lesion will develop into a cavity.
"The study shows dentists can identify which teeth are likely to develop cavities," Dr. Zandona said. "They can then institute a preventive measure such as a sealant or a fluoride treatment instead of waiting for lesions to become cavities. We don't want dentists to wait for a lesion to become a cavity. In reality, if a dentist sees a lesion that is active and has an ICDAS score higher than 1, chances are it will become a cavity."
The study provides information that wasn't previously available, according to Dr. Zandona.
"Now dentists can have more certainty about what path to take because of what we learned," she said. "Now we are focusing on identifying the metabolic signals on the dental plaque overlaying these lesions that can help us determine if these lesions are active."