Assessment of dental anomalies on panoramic radiographs: inter- and intraexaminer agreement

The presence of dental anomalies has been rated radiographically in a number of studies. However, since the reliability of the assessment of these anomalies has rarely been investigated, the aim of this study was to examine inter- and intraexaminer agreement in identifying morphological dental anomalies, such as tooth agenesis, dilacerated, pipette-shaped, blunt, pointed, and short roots. Pre-treatment panoramic radiographs of 40 patients (13 males and 27 females; mean age 27.7 ± 10.8 years) treated between 1983 and 2008 were selected. Four examiners independently assessed the radiographs twice. For a dilacerated root and agenesis, a definition was given. For pipette-shaped, blunt, or pointed roots, a drawing was shown, and for a short root, a ratio was used to identify the anomaly. Intraexaminer agreement of the assessments of the dental anomalies was presented by Cohen's Kappa and varied between -0.01 for short roots and 1.00 for agenesis. With respect to short roots, three of the examiners did not rate them to be present on at least one measurement occasion. This implies that intraexaminer agreement could not be calculated for these three examiners. Interexaminer agreement for dilacerated roots varied between 0.14 and 0.50, for pipette-shaped roots between -0.01 and 0.33, for blunt roots between 0.05 and 0.32, and for pointed roots between 0.17 and 0.37. All values for agenesis were 1.00. It can be concluded that assessing agenesis on panoramic radiographs is reliable. Rating the presence of dilacerated, pipette-shaped, blunt, pointed, and short roots on panoramic radiographs, however, does not result in a reliable assessment.