Inconsistencies in the differential diagnosis of open bite.

OBJECTIVE

To examine inconsistencies in the differential diagnosis of open bite.

MATERIALS AND

METHODS

Using visual judgments, a total of 77 anterior open-bite cases in the postpubertal growth period were grouped as either morphogenetic, functional, or combination. The same sample was also grouped as either hyperdivergent, normodivergent, or hypodivergent using mandibular-plane angle and conventional cephalometry. Kappa analysis was used to test the agreement between the 2 methods of evaluation, and chi2 tests were used to analyze the distribution of cephalometrically grouped hyperdivergent, normodivergent, and hypodivergent cases among the visually assessed morphogenetic, functional and combination groups and vice versa. A kappa score of 0.343 indicated a weak agreement between visual judgment and cephalometric methods of evaluation (P < .001).

RESULTS

Despite the expectation that cases evaluated as hyperdivergent using cephalometry would be visually evaluated as morphogenetic, more than half of the cases assessed as hyperdivergent were in fact classified as functional.

CONCLUSIONS

These findings highlight the inadequacy of relying solely on cephalometric evaluation to classify open bite.