Comparing 3D & 2D Facial Photography to Clinical Facial Form Analysis for Orthodontic Diagnosis

The primary goal of orthodontic treatment is a functional dental occlusion as well as an aesthetic smile in harmony with the lower 1/3 facial soft tissue. A 3-dimensional analysis of the patient’s dentofacial relations is crucial for proper treatment planning and it is ultimately the soft tissue that dictates the direction of the orthodontic treatment plan. The purpose of this pilot study is to study the difference of three different medias (3D photography, 2D photography, clinical patient evaluation) for facial form analysis. Specifically, to determine which photographic method most closely mimics clinical analysis of facial form for the purpose of orthodontic facial form diagnosis. Two orthodontists analyzed twelve facial measurements on 54 patients (21 male) via 3D photographs, 2D photographs and clinical evaluations. In addition, twelve of these patients were randomly chosen for two extra evaluation sessions for intra-rater reliability testing. The twelve categories are the most commonly used measurements by orthodontists to evaluate lower 1/3 facial form for diagnosis and treatment planning purposes. Krippendorff’s Alpha reliability testing was used with values >0.6 deemed substantially reliable. Results showed poor intra-rater reliability for both evaluators across all three media (only 22 out of 72 total categories substantially reliable) demonstrating the examiners were not reliably consistent with their evaluations. Furthermore, results showed poor reliability testing between the three different medias making comparisons of 3D vs. 2D vs. clinical evaluation difficult. Lastly, results showed poor inter-rater reliability for the two evaluators across all three media (zero substantially reliable categories) demonstrating that the two examiners did not agree on any of the facial evaluations. In conclusion, the two orthodontist did not reliably diagnose most of the 12 facial categories using the three given media of clinical, 2D photography and 3D photography and they also did not agree with each other’s diagnosis; therefore, it is difficult to determine if 2D or 3D photography provides more diagnosis similarities to clinical evaluation of facial form diagnosis