RESUMO
OBJECTIVES: The objective of this study is to assess the accuracy of the vertical tube shift method in identifying the relationship between the mandibular canal (MC) and third molars. MATERIALS AND METHODS: Two examiners assessed image sets of 173 lower third molar roots (55 patients) using forced consensus. The image sets comprised two methods: PERI, two periapical radiographs (taken at 0° and -30°), and PAN, a panoramic radiograph (vertical angulation of -8°) and a periapical radiograph taken at a vertical angulation of -30°. Cone beam computed tomography (CBCT) was the reference standard in the study. The responses were recorded for position (buccal, in-line with apex and lingual) and contact (present or absent). The McNemar-Bowker and McNemar tests were used to determine if the PERI and PAN methods would disagree with the reference standard (α = 5 %). RESULTS: The PERI and PAN methods disagreed with the reference standard for both position and contact (p < 0.05). CONCLUSION: The vertical tube shift method was not accurate in determining the relationship between lower third molars and the MC. CLINICAL RELEVANCE: The vertical tube shift is not a reliable method for predicting the relationship between lower third molars and the MC.