Evaluation of horizontal magnification on panoramic images

Abstract

This study evaluated the horizontal magnification of images taken from adults and pediatrics with PM 2002 CC Planmeca analogue machine. A series of 120 panoramic radiographs were obtained of 60 adults and 60 pediatrics. For all patients, negative impressions were used to make positive casts of the teeth. A caliper was used to measure the maximum mesiodistal length of the buccal surface of all teeth except canines on both casts and radiographs. The horizontal magnification factor was calculated for incisor, premolar, and molar regions by dividing the values obtained from the casts by the values obtained from the radiographs. Independent t-test and one-way analysis of variance (ANOVA) were used. The results indicated that with regard to adults, maxillary and mandibular incisor regions, unlike the other two sessions, didn't show significant difference of the mean magnification of horizontal dimension (P = 0.5). In pediatrics, the comparison between mean magnification factors of all subgroups showed significant difference (P < 0.0001). Despite the adults' radiographs, the results of pediatrics' radiographs showed significantly higher magnification than the index listed by the manufacturer of the radiographic machine used. The present study results point to the fact that PM 2002 CC Proline panoramic machine makes possible precise measurements on radiographs of adults' jaws in the horizontal dimension.