Radiographic prediction of inferior alveolar nerve injury in third molar surgery

Abstract

Data sources

Medline, Embase, relevant dental journals, reference lists of included studies and the World Health Organisation International Clinical Trials Registry.

Study selection

Studies evaluating the predictive accuracy of panoramic radiography for postoperative inferior alveolar nerve (IAN) injury reporting on at least one of the seven signs of IAN injury and providing data to calculate false-positive (FP), true-positive (TP), false-negative (FN) and true-negative (TN) proportions were included.

Data extraction and synthesis

Data were abstracted independently by two reviewers. Positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity were extracted or calculated. Overall pooled estimates of sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR) (LR-) and diagnostic odds ratio (DOR), with 95% confidence intervals (CIs) were calculated using a random effects model. Summary receiver operating characteristic (SROC) curves were also generated. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool (http://www.bristol.ac.uk/social-community-medicine/projects/quadas/quadas-2/).

Results

Eight studies were included. Only one study was considered to be at low risk of bias, one at low risk and the remainder at unclear risk. A summary of the pooled sensitivity, specificity and diagnostic odds ratios are shown in the table.

Conclusions

For all seven signs, the added value of panoramic radiography is too low to consider it appropriate for ruling out postoperative IAN in the decision-making before MM3 surgery. The added value of panoramic radiography for determining the presence of diversion of the canal, interruption of the white line of the canal and darkening of the root can be considered sufficient for ruling in the risk of postoperative IAN injury in the decision-making before MM3 surgery.