Frequency of Anatomical Indicators Related to the Mental Foramen and Mandibular Canal of Edentulous Patients on Digital Panoramic Radiographs

Document Type : Original Article


1 Assistant Professor, Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

2 Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

3 Post-graduate Student, Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran


Background:Determining the location of mandibular canal and mental foramen in the implant treatment is important to prevent any damage to the mental foramen and mandibular canal. The interpretation of a radiographic image depends on the individual interpretation of the observer. The aim of this study was to assess the agreement between two radiologists on the identification of mental foramen and mandibular canal.
Methods: In this study, 95 digital panoramic images ofedentulous patients were evaluated by two radiologists to determine the type of mental foramen according to the Yosue and Brooks classification as well as the type of mandibular canal according to the classification of Angelopoulos. Data were analyzed using SPSS version 17.
Results: The most common appearance of mental foramen was continuous type. The intra-examiner agreement on the type of mental foramen on the right and left sides was as much as 0.60 and 0.72, respectively. The highest frequency was observed in the anterior and middle one-third of the superior border of the mandibular canal related to type zero and posterior one-third related to type three. Type three in the inferior border of mandibular canal was the most frequent type in all one thirds. There was also a significant difference in the anterior, middle, and posterior one-third of the superior and inferior borders of mandibular canal observations.
Conclusion: The most common appearance of mental foramen on panoramic images was continuous type. The posterior one-third of mandibular canal was more clearly in panoramic images.


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