Introduction: Occlusal alterations are report by many patients submitted to the removal of third molars, postoperatively. Thus, it is interesting to assess whether this possible movement to the distal of lower second molars, following the removal of third molars, really exists.

Objective: The purpose of this study was to evaluate if there is an angle variation of the second molar’s long axis, in relation to that of the first molar, in digital periapical radiographic images, through the Digora ^® system.

Materials and methods: The present study included 40 digital periapical images of the lower molars region of 20 patients, between 15 and 25 years old, who presented non-erupted lower third molars, bilaterally, symmetric in their positioning, referred to extraction. The images were obtained after the extraction of the third molars. The Adobe Photoshop 7.0 ^® software was utilized to interpret the images and tracings of the long axes of the first and second lower molars and the intersection among them. The ImageJ 1.41 ^® software was utilized to obtain the angular values. All these measurements were accomplished in the images obtained in the immediate postoperative control of 2, 6 and 24 months, for the two groups studied.

Results and conclusion: The results showed no statistically significant difference between the experimental and control groups, in relation to the long axes of the first and second molars, not even after 2, 6 and 24 months, suggesting no movement to the distal of lower second molars, following the extraction of third molars.

Conflict of interest: None declared.