A simplified hypoplasia index

A simplified hypoplasia index for deciduous teeth has been developed. The index utilizes a two-digit system to signify the type and severity of the hypoplastic lesion. The types of lesions recorded are primary canine hypoplasia (PCH) and linear enamel hypoplasia (LEH). The severity ranges from minimal to severe and accounts for the presence of dental caries, dental restorations, and recurrent caries. To determine the reliability of the index, two tests were conducted. The first measure was a repeat reliability coefficient (test-retest) to calculate the stability of the instrument. This measure was calculated for two populations by two examiners under the same examination conditions and exams were conducted seven weeks apart. The second measure calculated the interrater reliability (standardization). Test results were analyzed by employing the Pearson product moment correlation. The repeat reliability coefficients were .75 (P less than or equal to .0001) and .74 (P less than or equal to .0001). The interrater reliability coefficient was .87 (P less than or equal to .0001). These data seem to indicate that the index is reliable over time and between examiners.