Background: The third molars of the lower mandibular are the most teeth with impaction because of to lack of eruption site. The canal of mandibular variations in impacted mandibular third molars are associated with a risk of injury be increased to the inferior alveolar nerve at the time of extraction. Radiography of panoramic is the most commonly used radiographic technique to see variations in the location of impacted third molars of mandibular and their relationship to the mandibular canal.  It is done to estimate the risk of inferior alveolar nerve injury.
Objective: To determine the distribution of mandibular canal variations on impacted mandibular third molars with panoramic radiographs.
Methods: Study method consist of 60 samples used panoramic radiographic. The sample observers by on the Rood & Shehab classification. To analyze the data of this study using the Friedman test.
Results: The highest distribution of the first distribution was owned by the interruption of the third molar root by 77%, the second was owned by darkening of the root of the third molar by 11%, the third was owned by the narrowing of the of the root of third molar by 6%, and the canal of mandibular diversion was 6%.
Conclusion: The highest distribution of canal interruption of mandibular, followed by darkening of the third molar root of impacted, then narrowing of the third molar root and diversion the canal of mandibular.

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