ارزیابی دقت تشخیصی رادیوگرافی دیجیتال Psp با پردازش معمولی و معکوس در ضایعات پری اپیکال

Background and objectives: periapical lesions in a clinical problem is that there are often difficulties in detecting it. since the diagnosis of periapical lesions in the periapical radiolucency on the observation area, so the diagnosis of periapical radiographic evaluation is important .the target of this study is to assess the diagnostic exactness of indirect digital radiography (psp) and the conventional processing in diagnosis of periapical lesions at invitro conditions. subjects and methods: in this experimental - laboratory research, 60 synthetic lesions were formed under the apex of teeth using of single-root premolar teeth placed in the dried mandible bone of sheep. these lesions were taken radiographs by two methods of digital and conventional. two oral and maxillofacial radiologists examined the presence or absent of lesions in psp pictures by conventional and reverse processing in each tooth.results: the average sensitiveness of observers in psp radiography with conventional processing in mm1, 0mm/5, mm%25 are 46%, 63.5%, and 93.3% respectively which were reduced to 45%, 60% and 86.6% with psp radiography of reverse processing. digital radiography with conventional processing has the characteristics of (66%) in comparison with the (63.3%) digital radiography of reverse processing.conclusion: there is no significant difference between the sensitiveness of digital radiography with conventional and reverse processing.