Skeletal Analysis with Smiling and Repose Profiles

Objectives: Determine if a lateral smiling profile or profile in repose image can be used to accurately assess skeletal jaw relationships. Methods: Profiles of 21 children, all 8 years of age, with varying degrees of facial prognathism or retrognathism were shown to a group of dental professionals and lay people. Raters were comprised of 17 dental professionals and 18 lay people who were shown the images and given 25 seconds to diagnose patient profile (convex, straight or concave), maxillary projection and mandibular projection with relation to the rest of the face. Correct profile and jaw positions were determined cephalometrically using the Andrew's analysis. Results were analyzed using a oneway ANOVA. Results: For dental professionals, profile in repose could significantly predict the correct profile of the patient (60.8%) than lateral smiling profile (52.4%), p= 0.0285. No significant differences were found between lateral smiling profile and profile in repose for assessing the accuracy of profile position of the maxilla (60.8%, 55.7%) or mandible (51.5%, 54.1%). For lay people, the lateral smiling profile could significantly predict maxillary projection with more accuracy (50.8%) than a repose profile (41.1%),p =0.0160. In addition, profile in repose could significantly predict mandibular projection (46.0%) with more accuracy than smiling profile (35.7%),p=0.0049. However, the accuracy in predicting all three categories correct was only 20% for the professionals and 8% for the lay people using either the lateral smiling profile or profile in repose. Conclusions: Profile images alone do not have sufficient accuracy in assessing the underlying skeletal structures. The addition of a lateral smiling profile helps in determining the position of the maxilla in trained professionals.