Evaluation of three imaging techniques for the detection of vertical root fractures in the absence and presence of gutta-percha root fillings.

AIM: To compare the accuracy of digital radiography (DR), multidetector computed tomography (MDCT) and cone beam computed tomography (CBCT) in detecting vertical root fractures (VRF) in the absence and presence of gutta-percha root filling. METHODOLOGY: The root canals of 100 extracted human single-rooted teeth were prepared and randomly divided into four groups: two experimental groups with artificially fractured root and two intact groups as controls. In one experimental and one control group, a size 40, 0.04 taper gutta-percha cone was inserted in the root canals. Then DR, MDCT and CBCT were performed and the images evaluated. Statistical analyses of sensitivity, specificity and accuracy of each imaging technique in the presence and absence of gutta-percha were calculated and compared. RESULTS: In the absence of gutta-percha, the specificity of DR, MDCT and CBCT was similar. CBCT was the most accurate and sensitive imaging technique (P < 0 .05). In the presence of gutta-percha, the accuracy of MDCT was higher than the other imaging techniques (P < 0.05). The sensitivity of CBCT and MDCT was significantly higher than that of DR (P < 0.05), whereas CBCT was the least specific technique. CONCLUSIONS: Under the conditions of this ex vivo study, CBCT was the most sensitive imaging technique in detecting vertical root fracture. The presence of gutta-percha reduced the accuracy, sensitivity and specificity of CBCT but not MDCT. The sensitivity of DR was reduced in the presence of gutta-percha. The use of MDCT as an alternative technique may be recommended when VRF are suspected in root filled teeth. However, as the radiation dose of MDCT is higher than CBCT, the technique could be considered at variance with the principles of ALARA.

Cyclooxygenase 2 plays a role in Emdogain-induced proliferation.

BACKGROUND AND OBJECTIVE: Enamel matrix proteins are involved in the development and regeneration of root cementum and in its attachment to dentin; however, the mechanisms through which this occurs have yet to be elucidated. The present study was therefore carried out to evaluate the mitogenic and proliferative responses of human periodontal fibroblast (HPLF) cells to Emdogain (EMD), and the potential role of cyclooxygenase 2 (COX-2) in this process. MATERIAL AND METHODS: We investigated the effects of EMD on 5-bromo-2'-deoxyuridine (BrdU) incorporation, colchicine freezing of mitosis, XTT [2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and Trypan Blue dye exclusion, with or without celecoxibe, a selective cyclooxygenase-2 (COX-2) inhibitor; we also evaluated the expression of COX-2 mRNA and COX-2 protein in response to EMD. RESULTS: EMD significantly enhanced mitosis in, and proliferation of, human periodontal ligament fibroblasts in a dose-dependent manner; however, there was a small increase of DNA synthesis only in response to a high dose of EMD (200 µg/mL). EMD (100 and 200 µg/mL) elicited an increase in COX-2 expression (p ≤ 0.05). Celecoxibe (20 µm) diminished the EMD-induced mitosis and proliferation of HPLF cells (p ≤ 0.05). CONCLUSION: Celecoxibe hampered EMD-induced mitosis and proliferation, which, in association with EMD-increased COX-2 expression, indicates that COX-2 may be involved in the proliferative response of HPLF cells to EMD.