Comparison of periapical radiography, panoramic radiography, and cone‑beam computed tomography for detecting implant‑related injuries to the inferior alveolar canal: An ex vivo study

Abstract

Background: The aim of this study was to evaluate the diagnostic potential of periapical radiograph,
panoramic radiograph, and cone‑beam computed tomography (CBCT) in detecting implant‑related
perforation of the inferior alveolar canals.
Materials and Methods: In this ex vivo study, a total of 45 dental implants were placed in 15 sheep
hemimandibles simulating two types of injuries to the inferior alveolar canal: pilot drill injury and
implant penetration into the canal. Fifteen implants were placed as the control group with 1 mm
distance from the inferior alveolar nerve (IAN) canal roof. An imaging phantom was prepared by
placing implant‑containing blocks in the posterior mandibular area on both sides of an artificial model
of the cranium. Panoramic and periapical radiographs as well as CBCT scans were obtained from
the imaging phantom. Two independent observers repeated image analysis over two sessions. The
area under the receiver operating characteristic curve (AUC) was used to determine diagnostic
accuracy. Interobserver and intraobserver agreements were obtained using Cohen’s kappa (α = 0.05).
Results: For detection of pilot drill injuries by observer 1, CBCT (AUC = 1) and
periapical radiograph (AUC = 0.889) were significantly better than using panoramic
radiographs (AUC = 0.694) (P < 0.001 and P = 0.014, respectively). For observer 2,
CBCT (AUC = 0.897) was also superior to panoramic radiography (AUC = 0.683) for this
purpose (P = 0.018). For detection of penetrative injuries to the IAN canal, periapical radiography
had an AUC of 0.995 and 0.986 for observers 1 and 2, respectively, while the AUC for panoramic
radiography was 0.990 and 0.948 for observers 1 and 2, respectively. The corresponding values
using CBCT were 1.000 and 0.995, respectively. No significant difference was observed between
the three modalities for detection of penetrative injuries (P > 0.05).
Conclusion: CBCT was better in detecting pilot drill injuries to the IAN canal compared to panoramic
radiograph. Therefore, in cases where clinical presentations suggest IAN disturbances, CBCT scan 

should be preferred. However, the diagnostic potential of periapical radiograph, panoramic radiograph,
and CBCT was not significantly different for detection of penetrative injuries to the IAN canal.
Key Words: Cone‑beam computed tomography, dental implants, mandibular canal, panoramic radiograph, periapical radiograph

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 Maryam Hosseini: Pubmed,Google Scholar