Background and aim:
Entrapment of foreign-bodies is a common phenomenon in traumatic events occurring in the maxillofacial region. The purpose of this study was to evaluate the efficiency of panoramic, CT, Cone-beam CT, MRI and ultrasonography in detecting different foreign-bodies in the maxillofacial region.

Methods:
Four different materials were used as foreign-body including metal, glass, rubber and wood. These particles were prepared in four different sizes from 2*2*2 mm to 5*5*5 millimeters. The foreign-bodies were then implanted into a sheep’s head in the infraorbital part of maxilla and mandibular buccal region. The panoramic, CT, Cone-beam CT, MRI and ultrasonography were obtained from the model and the images were blindly observed and analyzed by two radiologists. A four-point scale was used to interpret the visibility of found foreign-bodies.

Results:
CT had the best efficiency in detecting different foreign-bodies. Cone-Beam CT was the next useful technique. The ability of differentiating the foreign-bodies from the adjacent structures were poor in MRI and ultrasonography. As expected, the panoramic was only efficient in detecting metallic bodies.

Conclusion:
CT-scan can be introduced as the best imaging modality in detecting different foreign-bodies especially non-metallic ones. CBCT is also acceptable for metal, glass and rubber particles.