ABSTRACT
Objective To evaluate the accuracy and reliability of cone-beam computed tomography (CBCT) in the diagnosis of periodontal bone defects in the elderly.Methods The 38 teeth of 27 cases were collected and scanned both with CBCT technology and periapical radiography (PA).Periodontal bony defects were identified and linear measurements were made for all defects.All cases were treated with periodontal flap surgery with the bony defects and their linear measurements detected during operation as the gold standard.Results All periodontal bony defects were identified with CBCT with its accuracy rate of 100.0％ (72/72),but the buccal and lingual defects could not be measured by PA with its accuracy rate of 62.5％ (45/72).Linear measurements for all defects revealed no statistical differences between CBCT and direct measurement [(5.516 ± 0.393) mm vs.(5.385± 0.415) mm,t=1.948,P＞0.05],but there was a significant difference in linear measurement between PA and direct measurement [(6.311±0.439) mm vs.(5.411±0.418) mm,t=9.956,P＜0.05].Conclusions CBCT can offer the diagnostic information for periodontal bone defect from three dimensional direction in the elderly,provide objective and accurate assessment of alveolar bone resorption,and has higher accuracy and reliability.
ABSTRACT
<p><b>OBJECTIVE</b>To establish a novel nude mice model which can be visualized in real time and detected in a continuous and dynamic way for the development and metastasis of adenoid cystic carcinoma.</p><p><b>METHODS</b>Human adenoid cystic carcinoma cells, ACCM cell line, were infected with retroviral vector of pLEGFP-N1 and then screened for a single colony of ACCM-GFP cells. Cell proliferation and morphological analysis were conducted for ACCM and ACCM-GFP cells. Nude mice lingual carcinoma model was set up with ACCM-GFP cells injection and real time observation with fluorescence imaging on ACCM-GFP tumors was performed subsequently. Histological assay was analyzed for ACCM and ACCM-GFP tumors as well.</p><p><b>RESULTS</b>ACCM-GFP cells were able to express GFP stably in the long term. ACCM and ACCM-GFP cells showed no significant difference in cell proliferation and morphology, and no significant difference of histological characteristics in vivo could be found between ACCM and ACCM-GFP tumors. Tumor development could be monitored in real time with fluorescence imaging system in vivo.</p><p><b>CONCLUSION</b>GFP-expressing ACCM tumor model can be applied to detect and observe its development in the long term in a noninvasive, real time and dynamic way. It is also a kind of ideal in vivo mouse model for adenoid cystic carcinoma research.</p>