Updated comparison of the caries susceptibility of various morphological types of permanent teeth

In 1941, Klein and Palmer published a landmark study that ranked the relative susceptibility to dental caries of various morphological tooth types. Specifically, Klein and Palmer used-a four-step approach, which included derivation of., (1) an eruption schedule; (2) posteruptive tooth age; (3) cumulative number of decayed, missing, and-filled teeth and cumulative posteruptive tooth age; and (4) relative susceptibility values. Their study was conducted when dental caries prevalence and severity were generally high in the United States, prior to the introduction of preventive measures such as fluoride and dental sealants. This investigation used more recent data to assess whether declines in dental caries prevalence over time have been accompanied by changes in the relative susceptibility of permanent tooth types. Methods: The data source for this investigation was the oral examination component of the Third National Health and Nutrition Examination Survey. This investigation used analytical methods to derive the relative susceptibility values that were identical with those used during the Klein and Palmer study. Full sample weights were used with SUDAAN so that the descriptive estimates would be representative of the US population. Analysis was limited to children aged 4 through 20 years. Results: The investigation found six categories of Susceptibility, with molars being more susceptible than incisors, canines, or premolars. In general, susceptibility values declined since the Klein and Palmer study, providing additional evidence for a caries decline in the United States. First and second molar susceptibility values from the NHANES III data, however, intersected with those of Klein and Palmer, suggesting that factors specific to the molars, such as the selective use of dental sealants on these teeth, might be playing an additional role. Conclusions: Future research should explore factors that might explain the changes in relative susceptibility values over time.