Can anteroposterior skeletal pattern be determined from a silhouetted profile photograph? A cross-sectional study

Abstract

Objective:

To determine the degree to which the anteroposterior (AP) skeletal jaw relation can accurately be determined from a silhouetted clinical profile photograph and whether the level of agreement is influenced by patient vertical proportions.

Design:

Cross-sectional study.

Setting:

University Dental Hospital of Manchester, United Kingdom.

Participants:

Specialist orthodontists

Method:

Eight specialist orthodontists assessed 37 silhouetted profile photographs of individuals aged 11–19 years and determined the class and severity of AP skeletal pattern. These assessments were compared to corresponding lateral cephalometric radiographs, where ANB values, supplemented by an Eastman Correction and a Wits Appraisal, where appropriate, were used for sagittal skeletal classification.

Results:

The agreement between silhouette and cephalometric AP determination yielded a weighted kappa score of 0.207 (95% confidence interval [CI] 0.135–0.278), which indicates only a fair level of agreement. The silhouetted sagittal skeletal pattern classification, along with severity, agreed with the lateral cephalometric radiograph in 29% of instances. Class III individuals were identified correctly 19.2% of the time. There was a statistically significant difference in kappa scores between the high angle (K= 0.439; 95% CI 0.310–0.568) and low angle (K = 0.068; 95% CI 0.007–0.130) patients (P < 0.001), as well as the high and average angle (K= 0.151; 95% CI 0.031–0.270) patients (P < 0.05).

Conclusion:

AP skeletal pattern, as determined from a lateral cephalometric radiograph, has only a fair level of agreement to that from a silhouetted profile photograph. Vertical proportions were shown to have a significant effect on the determination of the sagittal skeletal pattern and class III skeletal patterns were shown to be the most difficult to identify from profile silhouettes.