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目的:比较不同性别12~16岁青少年上气道、舌骨及牙颌软硬组织差异及其相关性,为临床制定具有性别差异的诊疗参考。方法:选择70例骨性Ⅱ类青少年患者,男女比例为1∶1,年龄、垂直骨面型严格匹配。用Invivo 5进行三维重建并测上气道、舌骨及牙颌软硬组织指标,进行独立样本 t检验及Pearson相关性分析。 结果:男、女性患者舌咽体积分别为[(6.68±2.71) cm 3、(5.36±1.73) cm 3, P=0.019],男、女性患者舌骨垂直距离分别为[(101.56±16.72) mm、(92.44±19.11) mm, P=0.037],具有统计学意义。男、女性Y轴角、NP-FH、RH、PFH、AFH、FHR、OP-SN、IOB、U1-E、Sn-G均有统计学意义。男性上气道与颌骨有显著相关性,女性上气道与牙齿角度及软组织有显著相关性。 结论:男性舌咽体积更大,牙颌软硬组织趋向于 平面平整且上唇及颏部靠前的水平生长型。临床上制定不同性别的诊疗方案时,男性趋向于着重考虑颌骨指标对上气道及舌骨的影响,女性着重考虑牙性指标对上气道及舌骨的影响,旨在逐步建立反映不同性别患者特征的颌骨及牙性指标,为预判不同性别患者治疗后上气道形态及舌骨位置的改变提供一定参考依据。  相似文献   
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PurposeTo retrospectively assess immediate and 1-year success rate of type 2 endoleak (T2E) treatment with ethylene-vinyl-alcohol-polymer using three-dimensional (3D) image fusion guidance with cone beam computed tomography via trans-arterial embolization (TAE) or direct percutaneous sac injection (DPSI).Materials and methodsA total of 37 patients with T2E who were treated either using TAE (34/37; 92%) or DPSI (9/37; 8%) were included. There were 34 men and 3 women with a mean age of 86 ± 9 (SD) years (range: 67–104 years). Mean aneurysm diameter was 67 ± 14 (SD) mm (range: 42–101 mm) at pre-procedure evaluation. Immediate success was complete embolization of the sac and feeding artery. 1-year success was reduction or stability of the aneurysmal sac diameter based on pre-procedure and 12-month follow-up examinations. Safety (treatment-related complications), patient demographics, duration of procedure and contrast volume were reported.ResultsImmediate and 1-year successful outcomes were reported in 94% (n = 32) and 88% (n = 28) of patients after TAE and 100% (n = 9) and 89% (n = 8) after DPSI. T2E treatments were immediately successful for 95% of the procedures (41/43) and for 88% (36/41) at 1 year. Overall, T2E treatment was effective in 33 patients (89%). No major complications occurred. Mean procedure time and contrast volume were significantly different between the 2 techniques with respectively 87 ± 16 (SD) min (range: 65–120 min) and 75 ± 26 (SD) mL (range: 40–130 mL) for TAE and 32 ± 10 (SD) min (range: 20–50 min) (P < 0.01) and 6 ± 6 (SD) mL (range: 2–22 mL) (P < 0.01) for DPSI. Mean aneurysm diameter at 1-year was 68 ± 17 (SD) mm (range: 43–101 mm). No significant differences in the pre-procedure sac diameter were found at long-term follow-up between patients without T2E and those with persistent T2E (P = 0.1) in the successful embolization group (n = 33).ConclusionTAE or DPSI treatments of T2E with ethylene-vinyl-alcohol-polymer using 3D-image fusion guidance were immediately successful for 95% of the procedures and remained effective for 88%. Longer follow-up is necessary to assess sac stability in the case of persistent endoleak.  相似文献   
45.
The purpose of this study was to assess the pre- and postoperative position and dimensions of the inferior alveolar canal (IAC) following sagittal split osteotomy (SSO) and identify any association with postoperative neurosensory deficit (NSD) at 1 year. This retrospective cohort study enrolled consecutive patients who had SSO performed to correct skeletal malocclusion. The pre- and postoperative cone beam computed tomography data were superimposed to visualize differences in IAC position and dimensions. Subjective and objective neurosensory tests were used to determine NSD in the inferior alveolar nerve distribution. A total of 20 subjects were included. The preoperative distance from the lateral cortex of the IAC to the inner aspect of the lateral cortex of the mandible was significantly greater in sides with NSD when compared to sides without NSD (P = 0.01). A significantly greater reduction in the postoperative distance measurement was seen in sides with NSD when compared to sides without NSD (P = 0.01). The magnitude of mandibular movement was significantly increased in sides with NSD (P = 0.02). The preoperative location of the IAC, as well as certain changes in the mediolateral and vertical positions as a result of SSO, are risk factors for postoperative NSD.  相似文献   
46.
There is a paucity of guidelines for the dental profession to assess failure of endodontic therapy. While a successful treatment can be well defined by the absence of apical periodontitis and clinical symptoms after a period of observation, failed treatment has escaped a distinct standing over the years. This article highlights aspects of significance and concludes that research ought to better explore the general health properties of persistent apical periodontitis on root‐filled teeth and finally confirm the extent there is an association between apical periodontitis and adverse systemic health effects. Clearing this condition will determine whether clinicians should take a serious or relaxed attitude to persistent apical periodontitis subsequent to endodontic treatment.  相似文献   
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When a brass compensator is set in a treatment beam, beam hardening may take place. This variation of the energy spectrum may affect the accuracy of dose calculation by a treatment planning system and the results of dose measurement of brass compensator intensity modulated radiation therapy (IMRT). In addition, when X-rays pass the compensator, scattered photons are generated within the compensator. Scattered photons may affect the monitor unit (MU) calculation. In this study, to evaluate the variation of dose distribution by the compensator, dose distribution was measured and energy spectrum was simulated using the Monte Carlo method. To investigate the influence of beam hardening for dose measurement using an ionization chamber, the beam quality correction factor was determined. Moreover, to clarify the effect of scattered photons generated within the compensator for the MU calculation, the head scatter factor was measured and energy spectrum analyses were performed. As a result, when X-rays passed the brass compensator, beam hardening occurred and dose distribution was varied. The variation of dose distribution and energy spectrum was larger with decreasing field size. This means that energy spectrum should be reproduced correctly to obtain high accuracy of dose calculation for the compensator IMRT. On the other hand, the influence of beam hardening on kQ was insignificant. Furthermore, scattered photons were generated within the compensator, and scattered photons affect the head scatter factor. These results show that scattered photons must be taken into account for MU calculation for brass compensator IMRT.  相似文献   
50.
《Brachytherapy》2018,17(5):734-741
PurposeTo determine the long-term results of a Phase II trial of perioperative high-dose-rate brachytherapy (PHDRB) in primary advanced or recurrent gynecological cancer.Methods and MaterialsFifty patients with locally advanced and recurrent gynecological cancer suitable for salvage surgery were included. Unirradiated patients (n = 25) received preoperative chemoradiation followed by surgery and PHDRB (16–24 Gy). Previously irradiated patients (n = 25) received surgery and PHDRB alone (32–40 Gy).ResultsMedian followup was 11.5 years. Eight unirradiated patients (32%) developed Grade ≥3 toxic events including two fatal events. Local and locoregional control rates at 16 years were 87.3% and 78.9%, respectively. Sixteen-year disease-free and overall survival rates were 42.9% and 46.4%, respectively. Ten previously irradiated patients (40.0%) developed Grade ≥3 adverse events, including four fatal events. Local and locoregional control rates at 14 years were 59.6% and 42.6%, respectively. Fourteen-year disease-free and overall survival rates were 16.0% and 19.2%, respectively.ConclusionsPHDRB allows effective salvage of a subset of unfavorable gynecological tumors with high-risk surgical margins. Toxicity was unacceptable at the initial dose levels but deescalation resulted in the absence of severe toxicity without a negative impact on locoregional control. A substantial percentage of patients remain alive and controlled at >10 years including a few previously irradiated cases with positive margins.  相似文献   
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