1.IgG4-related sialadenitis.
Chinese Journal of Stomatology 2013;48(2):65-67
2.Giant cell lesions of jaw.
Chinese Journal of Stomatology 2006;41(2):126-128
6.Mobi-C cervical disc replacement:a five-year follow-up report in 19 cases
Da BAO ; Yuanzheng MA ; Xing CHEN
Chinese Journal of Tissue Engineering Research 2015;(39):6291-6295
BACKGROUND:Anterior cervical discectomy and intervertebral disc replacement have been extensively used in treatment of cervical degenerative disease. Its short-term therapeutic effects are encouraging, but it lacks of long-term and comprehensive evaluation.
OBJECTIVE:To observe the folow-up results of a group of cases of anterior cervical discectomy and Mobi-C intervertebral disc replacement for more than 5 years.
METHODS:A total of 25 cases of cervical spondylosis were treated in the 309 Hospital of Chinese PLA from January to September 2009. 19 of them were folowed up. Al patients received anterior cervical discectomy and Mobi-C intervertebral disc replacement. Twenty-three Mobi-C intervertebral disc prostheses were implanted. The range of motion was measured using lateral X-ray films during extension and flexion. Ectopic ossification was assessed by McAfee method. According to the cervical vertebra MRI images, the degeneration of adjacent segments was determined using Pearce classification. NDI score was used to evaluate the function of cervical spine. Pain improvement was evaluated using visual analogue scale score.
RESULTS AND CONCLUSION: A total of 19 patients were folowed up for 59-65 months, averagely 62 months. No significant difference in range of motion was detected before surgery and during final folow-up (P > 0.05). Ectopic ossification in two cases and the degeneration of adjacent segments in one case were found during final folow-up. No prosthesis loosening or displacement appeared. Visual analogue scale score and NDI score were significantly lower during final folow-up compared with that before surgery (P < 0.05). These results indicate that under the premise of reasonable choice of indications, the therapeutic effect of Mobi-C intervertebral disc replacement for degenerative cervical spondylosis was satisfactory in five-year folow-up. The range of motion was good, and the incidences of ectopic ossification and the degeneration of adjacent segments were low.
8.Feasibility of computer-aided nodule detection system in digital chest radiographs
Yan XU ; Da-Qing MA ; Wen HE ;
Chinese Journal of Radiology 2000;0(11):-
Objective To assess the usefulness of a computer-aided detection(CAD)system on detecting the pulmonary nodules in digital chest radiography.Methods Three hundred and twenty-eight digital chest radiographies along with corresponding chest computed tomography were selected for this study. Two senior chest radiologists interpreted these cases using the CAD system and marked the locations and sizes of all nodules with consensus,which were stored in a computer system as Gold Standard to evaluate the performance of the CAD system.Eight radiologists of various experience read these selected cases without and with the aid of CAD system and their results were stored in a computer system.The radiologists' performance was evaluated by using the receiver operating characteristic analysis.Comparison is made regarding the difference in Az values when CAD was not used versus when CAD was used by using the paired-samples t test.Results For small nodules,the sensitivity of this computer system used by the two senior chest radiologists in 100 digital radiographs was 78.1%(118.0/151).Without and with the assistance of CAD system,the nodule detection sensitivity of the radiology residents was 62.4% (94.2/151),77.4%(116.8/151)respectively,and the area under the curve of radiology residents was 0.769,0.836 respectively.Statistical analysis showed there was statistically significant difference between interpretation without and with the CAD system(P0.05).Conclusions This CAD system can help to enhance the radiologists' ability to detect small pulmonary nodules.This is especially helpful for radiology residents.
9.Dynamic analysis of the periodontal ligament
Yanhuan PAN ; Da MA ; Fan WANG
Journal of Practical Stomatology 2000;0(06):-
Objective:To investigate the influences of material properties and damping effect on the dynamic response analysis of human periodontal ligament. Methods: A 3-D finite element model of human teeth and periodontal tissue was built from graphic information obtained by CT scanning. Dynamic analysis was performed to investigate the influence of different damping effects on the stresses of periodontal ligament by the finite element method. Results: (a) No significant difference of stress between small and large deformation assumption was found, the variation was no more than 1.4%.(b) Dynamic response was obtained under ? varies from 0 to 1.2. After one mastication period, the residual stress at interior surface was larger than that at exterior surface, with a maximum value of ? r = 0.34 MPa at labial cervical area. Conclusion: Appropriate assumptions on material properties may reduce the cost of analysis. After one mastication period, some levels of residual stresses are in periodontal ligament and influenced by material damp.
10.Stress analysis of the periodontal ligament by submodel method
Yanhuan PAN ; Liang TANG ; Da MA
Journal of Practical Stomatology 1995;0(04):-
Objective:To improve stress analysis in stress-intensive regions of human periodontal tissue. Methods:Based on coarse analysis on the finite element(FE) model including human teeth and periodontal tissue, the submodel method was introduced to analyze the stresses in interested region such as apical. Results:Submodel analysis showed same stress distribution as FE model while more precision of stress value was obtained by submodel because refined mesh was used.Conclusion:More accurate stresses measurements in local regions can be obtained by submodel method.