Letters From Our Readers
To: Editor, The Angle Orthodontist
Response to: Accuracy of panoramic radiography in diagnosing maxillary sinus-root relationship: A systematic review and meta-analysis. Wentian Sun, Kai Xia, Li Tang, Chenlu Liu, Ling Zou, Jun Liu. The Angle Orthodontist. 2018;88:819–829.
Thank you very much for your interest in our article. We appreciate your insightful question and valuable suggestions.
In the study, to evaluate the robustness of the synthesized results, we investigated potential sources of heterogeneity through meta-regression analysis. Among the six factors investigated, only tooth type was statistically significant in affecting the diagnostic efficacy for type I sinus-root relationship (SRR) (P = .0081). To explain the statistical significance of the tooth type, the anatomical explanation as you mentioned, that the incidence of roots protruding into the maxillary sinus varied among different tooth types should be the best answer.1–6 The reason we did not discuss the tooth type matter further is that, together with the results of the sensitivity analysis and publication bias test, the robustness of the study was considerable.
This study was a diagnostic systematic review.7 Panoramic radiography and cone-beam computed tomography (CBCT)/computed tomography (CT) (the gold standard) were used to examine the same anatomical structures (the same teeth and the same maxillary sinuses), and the consistency of the two tests accounted for the accuracy of panoramic radiography. As we have disclosed in the “Results” section, especially the sections titled “Classification Change Between Index and Reference Test” and “Distance From Root Tips to the MSF,” there were obviously different diagnostic results between panoramic radiography and CBCT/CT, particularly for SRR type II, III, and IV. Since the same structures were examined, the difference in diagnostic accuracy must be explained by the characteristics of the two radiologic methods themselves, that is, superimposition, magnification, and so on.8,9 The diagnostic accuracy of panoramic radiography for different tooth types was not investigated in the present review, and we would like to see future studies addressing this interesting topic.