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1.
目的研究牙槽窝内保留颊侧部分牙根,对牙槽窝颊侧骨板高度及牙槽窝骨愈合速度的影响。 方法选择4只成年Beagle犬双侧下颌及第二、三、四前磨牙的远中根作为实验位点。采用平行对照随机分为以下3组:(1)血液充盈组:拔除前磨牙远中根,血液充盈后关闭创口;(2)Bio-Oss Collagen组:拔除前磨牙远中根,牙槽窝内植入Bio-Oss Collagen,牙槽窝表面覆盖Bio-Gide,严密关闭创口;(3)部分牙根+血液充盈组:去除前磨牙远中根牙冠及牙根的舌侧部分,保留颊侧部分牙根,血液充盈牙槽窝后关闭创口。术后12周拍摄Beagle犬下颌锥形束CT(CBCT),比较颊侧骨板高度变化以及牙槽窝内的成骨情况。采用SPSS 21.0统计软件对颊侧骨板高度吸收量进行秩和检验,检验水准α = 0.05。 结果术后12周,血液充盈组颊侧骨板高度降低(1.63 ± 0.67)mm,Bio-Oss Collagen组颊侧骨板高度降低(0.77 ± 0.58)mm,部分牙根+血液充盈组颊侧骨板高度降低(0.06 ± 0.10)mm。Bio-Oss Collagen组牙槽窝颊侧骨板吸收量小于血液充盈组,差异具有统计学意义(Z=-2.205,P = 0.027),部分牙根+血液充盈组颊侧骨板吸收量小于血液充盈组,差异具有统计学意义(Z=-3.361,P= 0.001),部分牙根+血液充盈组颊侧骨板吸收量小于Bio-Oss Collagen组,差异具有统计学意义(Z=-2.260,P= 0.024)。术后12周血液充盈组牙槽窝中间区域显示低密影,Bio-Oss Collagen组牙槽窝高密影,形态与牙根轮廓相似,部分牙根+血液充盈组可见较多地松质骨影像。 结论牙槽窝内保留颊侧部分牙根,相比牙槽窝内植入Bio-Oss Collagen,能更好地保存颊侧骨板高度。保留颊侧部分牙根具有促进牙槽窝内骨生成,加快牙槽窝骨愈合速度的作用。  相似文献   
2.
BackgroundAlthough DNA of high quality can be easily prepared from cultured cells with commercially available kits, many studies involve a large number of samples which increases the cost drastically. We optimized two simple and inexpensive methods for preparing DNA suitable for digital PCR from a small number of cells directly from wells of 96‐well plates.MethodsCells (number: 103‐104) were lysed with a Direct PCR® lysis buffer or a 10% Chelex100® solution. The lysates were further purified and concentrated by means of DNA precipitation with a blue‐colored glycogen as a carrier. PCR and digital PCR were used to evaluate the efficiency of the two methods.ResultsFor 1000 cells from one primary culture and two tumor cell lines, DNA was reproducible and obtained with recovery rate (obtained/expected amount of DNA) in the range of 50%‐90% as measured by the fluorometer dyes instrument Qubit. Using 8 out of a total of 10 µL DNA solution for 1000 cells, both conventional PCR and digital PCR were successful. For digital PCR, more than 1600 positive droplets were obtained for DNA from 1000 cells using the Direct PCR® method, corresponding to a yield efficiency of approximately 80%. Further reducing the number of cells down to 100 would be possible with 160 positive droplets expected. Both reagents are inexpensive (0.08€/sample).ConclusionsTwo methods are efficient, especially the Direct PCR® reagent‐based method provides a simple and inexpensive method for preparing DNA suitable for digital PCR from small number of cells.  相似文献   
3.
目的探讨利用碘化钾制备碘涂层钛板的可行性,并验证其抗菌性能。方法以碘化钾作为电解液,使用电泳沉积法将碘负载到钛板表面,制备出碘涂层钛板。通过扫描电镜与能谱分析,观察碘涂层钛板的表面征象和成分结构。实验分组:对照组是经过预处理但未行载碘的钛板,共10块;实验组是经过预处理后再行载碘的碘涂层钛板,根据电解液浓度的不同分为3组:1000 mg/L、2000 mg/L、4000 mg/L组,每组各10块。使用1×106 CFU/mL的金黄色葡萄球菌(ATCC25923)进行体外抗菌实验,并对其抗菌性能进行研究。结果碘涂层钛板外观呈灰色,表面可均匀覆盖一层平整、无塌陷的涂层,电镜下见其表面可形成碘涂层,局部散在分布大小不等的不规则陷凹。对照组、1000 mg/L组、2000 mg/L组、4000 mg/L组的钛板碘含量分别为0、5.10、10.32、15.05 mass%;其体外抗菌菌落计数分别为56.00±5.09、21.40±2.76、9.10±2.51和2.00±1.88,4组之间菌落计数比较差异均有统计学意义(P<0.05)。结论碘化钾作为电解液,使用电泳沉积法可成功制备出碘含量稳定、涂层分布均匀的碘涂层钛板。体外抗菌实验证明碘涂层钛板的抗菌性能强于未载碘钛板。  相似文献   
4.
Segmental mandibular defects require reconstruction. The fibula flap serves as a versatile flap in restoring mandibular contour and bony height. With the advances in computer-aided design and additive manufacturing technology, an innovative “one-piece” patient-specific reconstruction plate to facilitate double-barrel fibula flap shaping and bone securing was developed; the plate is described in this study. The “one-piece” plate is fabricated with individualized specifications and is mainly composed of three components: the long-bar reconstruction plate, a short-bar plate, and connecting bars. Our initial experiences showed that mandibular reconstructive surgery was greatly facilitated by the “one-piece” reconstruction plate for double-barrel fibula flap reconstruction and achieved satisfactory outcomes. A well-designed clinical trial is required to confirm the superiority of the “one-piece” reconstruction plate in the future. ClinicalTrials.gov registration: NCT03057223.  相似文献   
5.
The aim of this retrospective study was to use computer-aided design and manufacturing (CAD/CAM) patient-specific plates and cutting guides for the waferless positioning and fixation of the maxilla after bimaxillary osteotomies in cases of hemifacial microsomia with condylar dysplasia or absence of the temporomandibular joint (TMJ), and to compare the results with the CAD/CAM fabricated surgical wafer by 3-dimensional analysis. Eighteen patients were selected from the hospital database, preoperative surgical planning and simulation were done on 3-dimensional computed tomographic models for all patients, and they were divided into Group I – in which CAD/CAM patient-specific cutting guides and plates were used; and Group II – in which CAD/CAM fabricated surgical wafers were used. Finally, the outcome was evaluated by comparing planned with postoperative outcomes. The largest discrepancies of the Le Fort I segment were 0.50 (0.18) mm in the anteroposterior direction and 0.82 (0.60)° in the yaw orientation with Group I. The largest discrepancies of the Le Fort I segment were 1.32 (1.40) mm in superioinferior direction and 8.48 (7.73)° in the yaw orientation with Group II. The CAD/CAM patient-specific cutting guides and plates proved to be reliable and have great value in improving the accuracy in repositioning the Le Fort I segment and in the efficacy of orthognathic treatment of hemifacial microsomia with condylar dysplasia or no TMJ. The CAD/CAM patient-specific cutting guides and plates are therefore a useful alternative to the wafer technique.  相似文献   
6.
Titanium osteosynthesis is currently the fixation system of choice in maxillofacial traumatology. Biodegradable osteosynthesis systems have the ability to degrade in the human body. The aim of this study was to conduct a systematic review, with meta- and trial sequential analyses, to assess the efficacy and morbidity of biodegradable versus titanium osteosynthesis after maxillofacial trauma. MEDLINE, Embase, and CENTRAL were searched for randomized controlled trials and prospective and retrospective controlled studies. Five time periods were studied: perioperative, short-term (0–4 weeks), intermediate (6–12 weeks), long-term (>12 weeks), and overall follow-up. After screening 3542 records, 24 were included. All had a high risk of performance and detection bias due to the nature of the interventions. Meta-analysis showed no differences in efficacy or morbidity between biodegradable and titanium osteosynthesis. The risk of perioperative screw breakage was significantly higher (risk ratio 17.13, 95% confidence interval 2.19–34.18) and the symptomatic plate removal rate lower in the biodegradable group (risk ratio 0.11, 95% confidence interval 0.02–0.57), which was confirmed by the trial sequential analysis. The quality of evidence ranged from very low to moderate. Based on the narrative review and meta-analyses, current evidence shows that biodegradable osteosynthesis is a viable alternative to titanium osteosynthesis when applied in the treatment of maxillofacial trauma, with similar efficacy but significantly lower symptomatic plate removal rates. Perioperative screw breakage occurred significantly more often in the biodegradable group compared to the titanium group.  相似文献   
7.
目的比较3种内固定方式治疗股骨远端Müller分型C2、C3型骨折的疗效。方法回顾性分析2013年2月至2017年2月期间宁波市第六医院创伤骨科收治的58例股骨远端Müller分型C2、C3型骨折患者资料。根据内固定方式不同分为3组:单切口锁定钢板组(A组)21例,男13例,女8例;年龄为(50.6±12.9)岁。双切口锁定钢板联合重建钢板组(B组)18例,男11例,女7例;年龄为(53.5±13.0)岁。单切口锁定钢板联合重建钢板组(C组)19例,男10例,女9例;年龄为(48.1±12.2)岁。比较3组患者的手术时间、术中出血量、术中C型臂透视次数、骨折愈合时间、术后并发症发生率、膝关节活动度及膝关节功能等。结果3组患者术前一般资料比较差异均无统计学意义(P>0.05),具有可比性。3组患者术中C型臂透视次数、随访时间及术后并发症发生率比较差异均无统计学意义(P>0.05)。但A组、C组患者的手术时间[(96.7±16.4)、(101.9±16.5)min]和术中出血量[(237.8±47.5)、(253.6±46.6)mL]显著少于B组患者[(114.9±20.1)min、(290.1±60.9)mL],差异均有统计学意义(P<0.05)。B组、C组患者的骨折愈合时间[(6.9±1.6)、(6.6±1.7)个月]显著短于A组患者[(8.4±1.9)个月],术后12个月膝关节活动度(91.7°±16.7°、90.9°±14.4°)显著大于A组患者(78.8°±14.4°),术后12个月膝关节功能恢复优良率[77.8%(14/18)、73.7%(14/19)]显著高于A组患者[57.1%(12/21)],差异均有统计学意义(P<0.05)。结论采用股骨远端前外侧切口外侧应用锁定钢板、前侧附加重建钢板固定治疗股骨远端Müller分型C2、C3型骨折,固定坚强、对周围软组织损伤相对较小,兼具单切口锁定钢板和双切口内外侧锁定钢板固定的优点,术后患者膝关节功能恢复良好。  相似文献   
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10.
目的探讨锁定钢板治疗复杂胫骨平台骨折患者的临床疗效,分析并发症发生的原因并提出预防处理方法。 方法回顾性分析2016年1月至2019年1月采用胫骨锁定钢板内固定治疗56例复杂胫骨平台骨折患者的临床资料,根据Rasmussen膝关节功能评分评估手术疗效,观察术后并发症发生情况。 结果平均随访时间(12±6)个月。末次随访时根据Rasmussen膝关节功能评分标准,优25例、良26例、中5例,优良率91%。术后出现1例伤口感染,2例膝关节轻度内翻,1例膝关节不稳定。 结论胫骨锁定钢板治疗复杂胫骨平台骨折患者手术时间短、损伤小,患者术后膝关节功能恢复满意,但仍存在一定并发症,要术者做好充分的术前评估,熟练掌握手术技巧,尽可能减少术后并发症的发生。  相似文献   
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