[Comparative study of measurement of posterior tooth crowding between the dental panoramic xray and dental scanner].

The purpose of this work was to compare measurements of the posterior crowding in the mandibular arcade between two types of radiographic examinations: the dental panoramic one and the dental scanner. Our sample is composed of 12 patients before treatment orthodontic, with an average age of 16 + 4 years. These patients presented an posterior crowding on dental panoramic radiography accepted the catch of a dental scanner to re-examine this crowding. To make this study, we measured on dental panoramic radiographies and the dental scanners of each patient posterior available space and posterior necessary space according to the technique of Merrifield and we calculated the posterior crowding for each case. The comparison of the two variables was carried out by using the Test T of Student. The results our study shows that: Dental panoramic radiography raises the posterior dental crowding when this compared to the dental scanner (Student, p < 0.05). The percentage of enlarging of this crowding varies enormously between 18 % and 73% with an average of 48.58 % +/- 15, 90.