Periapical radiography and cone beam computed tomography for assessment of the periapical bone defect 1 week and 12 months after root-end resection.

OBJECTIVES: Our aim was to compare periapical radiography and cone beam CT (CBCT) for assessment of the periapical bone defect 1 week and 12 months after root-end resection. METHODS: 50 patients (58 teeth) with a persisting apical periodontitis in a root-filled tooth (incisor, canine or premolar) were treated with root-end resection. 1 week and 12 months post-operatively, a CBCT scan (NewTom 3G) and a periapical radiograph (Digora) were obtained. Three observers detected and measured the periapical bone defects on periapical radiographs and CBCT images (coronal and sagittal sections). RESULTS: 1 week post-operatively, a periapical bone defect area was measured in all teeth by all observers. The defect was 10% smaller on periapical radiographs (mean = 12.4 mm2, SD = 8.2) than on the CBCT images measured in the coronal plane (mean = 13.0 mm2, SD = 7.8), a difference which was not statistically significant (P = 0.58). 12 months post-operatively (n = 52), there was considerable variation between the observers' detection of a remaining defect on the periapical radiographs and the CBCT images. The average agreement between the periapical radiograph and the CBCT images in the coronal sections was 67%, and more defects were detected on CBCT than on periapical radiographs. CONCLUSIONS: On average, the periapical bone defect measured on periapical radiographs was approximately 10% smaller than on coronally sectioned CBCT images 1 week post-operatively. More remaining defects were detected 1 year after periapical surgery on CBCT images than on periapical radiographs, but it is uncertain how this information is related to success or failure after root-end resection.

Healing assessment of osseous defects of periapical lesions associated with failed endodontically treated teeth with use of freeze-dried bone allograft.

Freeze-dried bone allograft (FDBA) has been used extensively in periodontal surgery and in the treatment of pocket osseous defects resulting from inflammatory periodontal disease. No other endodontic investigation has used this type of graft material in the treatment of bony resorptive defects of the periapical lesions associated with failed endodontic therapy. Therefore this study was conducted with the use of FDBA, to assess healing ability of osseous defects after removal of periapical lesions associated with failed endodontically treated teeth. In all patients periapical lesions were surgically removed with retrograde amalgam seal and the graft material was then carefully packed without pressure into the bony defect. The lesions were fixed in 10% neutral buffered formalin and prepared for histologic examination. Long-term recall demonstrated bone regeneration and good tolerance of allograft material by the periapical tissues. The periapical lesions were either periapical granulomas or apical periodontal cysts. We conclude that FDBA is a biocompatible material of osteogenic potential and can be used effectively in treating osseous defects of periapical lesions associated with failed endodontically treated teeth.