Prediction of mesio distal width of unerupted permanent canines and premolars in panoramic radiographs

Prediction of mesiodistal width of unerupted permanent canines and premolars in mixed dentition period is necessary for space analysis. Use of panoramic radiographs instead of periapical radiographs in space analysis decreases the cost and X-ray exposure. The aim of this study was prediction of mesiodistal width of unerupted permanent canine and premolars by panoramic radiographs. Panoramic radiographs and dental casts of 60 orthodontic patients were selected. The largest mesiodistal width of dental crown of upper and lower canines and premolars on the panoramic and dental cast and also mesiodistal width of lower incisors on dental cast were measured, SPSS was used and data were analyzed by Pearson's coefficient correlation between panoramic, cast and linear regression analysis and paired sample T-test. R for predication of total unilateral mesiodistal width of permanent canine and premolars from cast and panoramic in upper jaw was 0.589 and in lower jaw was 0.69l. R for prediction of mesiodistal width for unerupted canine and premolars by use of lower incisors width from dental cast and radiographic width of upper permanent canine for upper jaw and lower second premolar far lower jaw were respectively 0.664 and 0.999. Based on introduced linear equation for prediction of mesiodistal width of canine and premolars, the best equation resulted from use of lower incisor width from dental cast and one radiographic agent which is canine in upper arch and second premolar in lower arch.