The assessment of antero-posterior dental base relationships.

The reliability and validity of four methods of assessing skeletal pattern (Reidel's method, Eastman correction, Ballard's method, and 'Wits' analysis) from cephalometric tracings have been examined, and the levels of agreement between them investigated. The possibility of the Y-axis length and SN-Y-axis angle having a bearing on the skeletal pattern was also examined. Strong correlation was found between the four methods considered.

Resorption of the crown of an unerupted permanent molar.

This case report describes an unusual phenomenon where resorption occurred in the crown of an unerupted permanent molar. It was an incidental radiological finding. After eruption the tooth was extracted.

The effect of beam collimation in lateral radiographic cephalometry.

A study was carried out to compare the image contrast of lateral cephalometric radiographs taken with and without the modified beam collimation and to evaluate the effect of this on the reliability of cephalometric measurements. The findings indicated that the cephalographs taken with modified beam collimation consistently showed a higher image contrast than the cephalographs taken with standard beam collimation. Despite this, however, there was no significant difference in the reliability of cephalometric measurements between the two groups of films.