Identification of cephalometric landmarks in unilateral cleft lip and palate patients: are there alternatives for point A, ANS, and PNS?

OBJECTIVE To test the reliability of some cephalometric measurements in unilateral cleft lip and palate patients. Measurements with A, ANS, and PNS, were compared to measurements performed with alternatives for point A, ANS, and PNS: A1, A2, ANS1, ANS2, and PNS1. PATIENTS One hundred sixty-four children with complete unilateral cleft lip and palate (UCLP), with a lateral head film taken at age 4 to 6 years. MEAN OUTCOME MEASURES Intraobserver and interobserver reliability for cephalometric measurements including A, ANS, PNS or their alternatives: Dahlberg errors, systematic errors, and Pearson correlation coefficients were calculated. RESULTS The measurements using ANS and PNS or their alternatives, were comparable. The systematic error between observers for measurements using A2 was less than for measurements using A or A1. The scatterplot of point A showed a slightly better distribution of the points than the plots of A1 and A2. CONCLUSIONS Although the landmarks A, ANS, and PNS are hard to trace in UCLP patients with tooth germs in the anterior maxilla, no better landmarks were found in this study. Cephalometric studies using A, ANS, and PNS in UCLP patients should be interpreted with caution.