Reverse Intra-oral Periapical Radiography For Mandibular Posterior Teeth


Aims: To satisfy the newly reverse modified intra-oral periapical projection, in order to reduce the pa-tient discomfort and eliminate gagging reflex during periapical radiography of the lower posterior teeth. Materials and methods: Twenty voluntaries patients have been used in this research aged between 20-25 years, each patient subjected for two intra-oral periapical radiographic examinations for lower posterior teeth (premolars and molars). The first radiographic exami-nation has been made with ordinary principles of intra-oral periapical radiographic projec-tion, while the second radiograph has been made with reverse modified principles of intra-oral periapical radiographic projection. Five independent examiners (two oral radiographer, oral surgeon, oral diagnosis and oral medicine), rated the two radiographic images obtained from both radiographic examination methods. Image quality was assessed by rating the visi-bility of five anatomical landmarks: tooth structures identification (enamel, dentin and root can-al system), bone trabiculation, mental foramen borders, inferior dental canal borders and lamina du-ra. Results: The data collected from the evaluation of the radiographic images obtained from both radiographic projections were analyzed by paired samples chi-square test, which shown no significant difference (P>0.05) in image quality obtained from both techniques for five selected structures. The bone trabeculae and the lamina dura given higher rating of total score with ordinary technique (54, 49 points respectively) when compared with reverse radi-ographic technique (47, 41 points respectively). The highest percentage of unrecognized shadow of mental foramen and the inferior dental canal with use of ordinary radiographic technique (40%, 30% respectively), while the other examined anatomic structures (tooth structure, bone trabeculae and lamina dura) can be identified clearly with both radiographic techniques. Higher percentage of gag reflex and pain discomfort was observed with ordinary technique projection (45%, 40% respectively) in comparison with reverse technique projec-tion (0%, 5% respectively). Conclusion: the reverse intra-oral periapical radiographic technique can be used accurately in the radiographic projection of the mandibular posterior teeth; with minimal pain discomforted and with eliminated gagging reflex initiation.