Condylar guidance: correlation between articular morphology and panoramic radiographic images in dry human skulls

Statement of problem. Several studies have shown the unreliability of recording and reproducing the condylar guidance in semiadjustable articulators. Purpose. The purpose of this study was to determine the correlation between the anatomic shape of the articular eminence and the corresponding panoramic radiographic image in dry skulls. Material and methods. Two metal wires were adapted and fixed to the inner and outer surfaces of the articular eminences In 25 human skulls. The Inner (thicker) wire was fixed to the middle of the most concave aspect of the articular eminence in an anterior-posterior direction. The outer (thinner) wire was attached to the inferior aspect of the zygomatic arch adjacent to the articular eminence. Panoramic radiographic images were recorded by the same operator at the same time and with the same panoramic radiographic unit (Orthoralix SD). Impressions were made of the condylar fossae in 25 human dry skulls. Tracings of the incline of the articular eminence on the panoramic radiographs and the impression sections were compared. Each measurement was repeated twice by 2 operators. The results were subjected to the Pearson correlation statistical analysis (alpha=.05). Results. The outline of the articular eminence in a panoramic radiographic image was identified as a thinner superior radio-opaque line above a thicker radio-opaque outline of the inferior-lateral aspect of the zygomatic arch. A significant correlation was found between the sagittal inclination of the anatomic articular eminence outline and the corresponding panoramic radiographic image for both right (R=0.802; P=.001) and left (R=0.561; P=.004) sides. A significant correlation was found between articular eminences on left and right sides in the same skull (P=.025). Conclusions. The panoramic radiographic image of the sagittal inclination of the articular eminence consistently replicated the eminence inclinations in the 25 human skulls evaluated.