Radiographic and tomographic analysis of the relationship between inferior third molars and the mandibular canal
DOI:
https://doi.org/10.7308/aodontol/2016.52.4.03Keywords:
Radiography, Panoramic, Molar third, Cone-beam computed tomographyAbstract
Objetctive: This research aimed to evaluate the intimate relationship between impacted lower third molars and the mandibular canal in panoramic images and cone beam computed tomography (CBCT).
Methods: The sample consisted of 432 CBCTs and 713 panoramic radiographs. A sample of 13 pairs of exams (panoramic radiography and CBTC) were obtained, totaling 20 teeth from patients who received dental care at a private radiology unit in the city of Patos, PB, Brazil. Two different examiners carried out the analysis in two distinct moments. The panoramic radiographs were analyzed according to Winter, Félez-Gutierrez, and Koong classifications. The CBTC was considered the gold standard for the evaluation. Data were analyzed descriptively by using the Microsoft Excel 2013 program, through graphs, charts, and percentages.
Results: According to the Winter classification, the most frequent position of the lower third molars was Mesio Angular. The most prevalent radiographic signs were narrowed channel and islet-shaped apex in the Félez-Gutiérrez classification, while in the Koong classification, the signs of narrowed channel and superimposed apexes were the most frequent. In the CBCT scans, the most frequent relationship was the channel passing below the third molars. In the comparison of the radiographic signs with the gold standard, 45% of false positives were found in both the Félez-Gutiérrez and Koong classifications.
Conclusion: The CBTC is the best choice for the surgical plan, especially in the cases in which there is intimate contact between the lower third molars and the mandibular canal.
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