Osteocytic Sclerostin Expression in Alveolar Bone in Rats With Diabetes Mellitus and Ligature‐Induced Periodontitis

Background: Osteocytic sclerostin inhibits bone formation, and its expression is stimulated by tumor necrosis factor (TNF)‐α. This study investigates sclerostin and TNF‐α expression in rats with diabetes mellitus (DM) and periodontitis. Methods: Rats were divided into control (C), periodontitis (P), and DM + periodontitis (DP) groups. After induction of DM by streptozotocin, periodontitis was induced by ligature. At day 0 (control) and at days 3 and 20 after induction of periodontitis, alveolar bone, osteoclasts, osteoid area, and TNF‐α and sclerostin expression were evaluated. Results: The distance between the cemento‐enamel junction and the alveolar bone crest of the DP group was longer than that of the P group at day 20 after induction of periodontitis, but the number of osteoclasts was not different. Osteoid area decreased in both the P and DP groups by day 3, but whereas sustained osteoid suppression was observed in the DP group at day 20, osteoid formation was increased in the P group. The number of sclerostin‐positive osteocytes increased in both groups at day 3, but the increased number of sclerostin‐positive osteocytes was maintained only in the DP group through day 20. The number of TNF‐α–positive cells increased more in the DP group than in the P group. Conclusions: Enhanced alveolar bone loss, suppressed bone formation, and prevalent TNF‐α expression were characteristic of the DP group compared with the P group. Suppressed bone formation in the DP group was observed simultaneously with increased sclerostin and TNF‐α expression. These results suggest that upregulated osteocytic sclerostin expression in periodontitis accompanied by DM may play a role in suppressed bone formation.     

Sensitivity and Specificity of Radiographic Methods for Predicting Insertion Torque of Dental Implants

Background: Subjective radiographic classifications of alveolar bone have been proposed and correlated with implant insertion torque (IT). The present diagnostic study aims to identify quantitative bone features influencing IT and to use these findings to develop an objective radiographic classification for predicting IT. Methods: Demographics, panoramic radiographs (taken at the beginning of dental treatment), and cone‐beam computed tomographic scans (taken for implant surgical planning) of 25 patients receiving 31 implants were analyzed. Bone samples retrieved from implant sites were assessed with dual x‐ray absorptiometry, microcomputed tomography, and histology. Odds ratio, sensitivity, and specificity of all variables to predict high peak IT were assessed. Results: A ridge cortical thickness >0.75 mm and a normal appearance of the inferior mandibular cortex were the most sensitive variables for predicting high peak IT (87.5% and 75%, respectively). A classification based on the combination of both variables presented high sensitivity (90.9%) and specificity (100%) for predicting IT. Conclusions: Within the limitations of this study, the results suggest that it is possible to predict IT accurately based on radiographic findings of the patient. This could be useful in the treatment plan of immediate loading cases.     

RANKL和OPG在不同骨移植材料拔牙位点保存区的表达

目的 通过观察破骨细胞核因子kB受体活化因子配体(receptor activator nuclear factor kappa B ligand,RANKL)和骨保护因子(osteoprotegerin,OPG)在不同骨移植材料拔牙位点保存时骨构建过程中表达变化,探讨破骨细胞对不同骨移植材料植入拔牙窝内在引导骨再生中的作用.方法 选取6只12月龄雄性beagle犬,微创拔除上下颌双侧第一侧切牙,将4个位点随机做不同处理,A组填人富血小板纤维蛋白(platelet-rich fibrin,PRF),B组填入骨诱导活性材料(osteoinduction active material,OAM),C组填入羟基磷灰石生物陶瓷(coralline hydroxyapatite,CHA),D组空置(对照).6只犬随机分别于术后4周和12周各处死3只,制作牙槽骨标本.免疫组化检测24个拔牙位点保存制作的犬牙槽骨标本中RANKL与OPG的表达变化.结果 术后4周骨组织中OPG的表达A组高于B组、C组和D组(P＜0.05),RANKL的表达D组高于C组、B组和A组(P＜0.05).术后12周骨组织中OPG的表达D组高于C组、B组和A组(P＜0.05),RANKL的表达C组高于B组、A组和D组(P＜0.05).结论 骨移植材料在骨改建过程中通过促进成骨细胞分化成熟而刺激OPG表达升高,抑制破骨细胞.提示骨移植材料通过调控RANKL和OPG在拔牙窝新骨形成过程中发挥作用.     

67名正常青年人上前牙区唇、腭侧骨厚度测量分析

目的:对汉族正常青年人上前牙区不同位点的唇、腭侧牙槽骨厚度进行测量,为术前评估、治疗方案制定及预后评估提供参考。方法:通过锥形束CT(CBCT)对67名符合条件的汉族青年志愿者进行上颌骨扫描。三维重建后,对前牙区唇、腭侧骨厚度进行测量。利用SPSS17.0软件包对测量数据进行配对t检验、独立样本t检验、方差分析及χ2检验。结果:1唇侧骨板除所有前牙L5处及上颌尖牙L1处厚度均数>1.00 mm外,其余测量位点唇侧骨板厚度均数均<1.00mm,而腭侧骨板厚度均数均>1.00 mm;2唇侧骨板厚度均小于腭侧骨板厚度(P<0.001);33种前牙唇侧骨板厚度在参考线L3与L4处厚度最小(P<0.001),腭侧骨板厚度自L1至L5逐渐增大(P<0.05);4仅在上颌尖牙L2处及所有前牙L5处唇侧骨板厚度<1.00 mm的频率<50%,男性上颌侧切牙L3、L4处及上颌尖牙L4处唇侧骨板缺如所占频率>50%;5男性切牙区唇侧骨板凹陷角度较尖牙小(P<0.05),唇侧骨板最凹点与根尖点之间的距离在男性上颌中切牙最大(P<0.05),女性牙位间无显著差异。结论:正常青年人上前牙牙槽骨骨板菲薄甚至缺如,且唇、腭侧骨厚度和形态存在差异。     

LISS钢板与髁钢板置入修复股骨远端骨折:骨愈合及膝关节功能预后差异性

背景：近年来随着对股骨远端骨折的深入研究,治疗方式已经从传统的保守治疗转变为积极的手术治疗。目前关于股骨远端骨折的各种内固定方案报道很多,但是系统的预后比较研究报道较少。
　　目的：对比股骨远端骨折患者分别采取LISS钢板与髁钢板置入内固定对其预后康复影响的差异,并为这类患者内固定方案的选择积累经验。
　　方法：选取2009年3月至2013年1月收治的78例股骨远端骨折患者,按随机数字表法分为两组,每组39例。LISS钢板组采用LISS钢板置入内固定方案,髁钢板组采用髁钢板置入内固定方案。记录两组患者术中及术后相关指标、出院后第12个月末Evanich评分及随访期间不良事件发生率。
　　结果与结论：LISS钢板组切口长度及骨折愈合时间短于髁钢板组(P <0.05)。出院后第12个月末,两组疼痛及稳定性评分差异无显著性意义(P >0.05);而LISS钢板组活动度、股四头肌力量评分及Evanich总分均高于髁钢板组(P <0.05),减分项目少于髁钢板组(P <0.05)。LISS钢板组随访期间不良事件发生率为5%(2/39),髁钢板组不良事件发生率为21%(8/39),两组差异有显著性意义(P <0.05)。提示相较于髁钢板,LISS钢板置入内固定修复股骨远端骨折能有效促进骨折愈合及膝关节功能恢复,并发症较少,是一种较为理想的骨科内固定方式。     

α-玉米赤霉醇对小鼠骨髓间充质干细胞向成骨细胞分化过程中OPG和RANKL蛋白表达的影响

目的 探讨α-玉米赤霉醇(α-zearalanol,α-ZAL)对小鼠骨髓间充质干细胞(Bone marrow-derived mesenchymal stem cells, BMSCs)向成骨细胞增殖、分化的影响。方法 采用全骨髓培养差速贴壁法体外分离培养小鼠骨髓间充质干细胞,取第3代细胞分为空白对照组、雌二醇阳性对照组、低浓度α-ZAL组、中浓度α-ZAL组,高浓度α-ZAL组。镜下每天观察细胞形态变化,碱性磷酸酶染色鉴定成骨细胞纯度,MTT实验测定细胞增殖活性绘制细胞生长曲线,采用酶联免疫吸附法(ELISΑ)测定碱性磷酸酶(alkaline phosphatase,ALP)、骨形态发生蛋白2( Bone morphogenetic protein-2,BMP-2),运用蛋白免疫印迹法（Western blotting,WB）检测护钙素（Osteoprotegerin,OPG）和NF-KB受体活化配体（Receptor actiator of nuclear factor-KB ligand, RANKL）的蛋白水平表达变化。结果 不同浓度的α-玉米赤霉醇可显著的促进小鼠骨髓间充质干细胞向成骨细胞增殖、分化,增加细胞活性（P<0.05）,明显提高小鼠骨髓间充质干细胞向成骨细胞分化后ALP和BMP-2的表达（P<0.05）,并且显著的上调了成骨细胞内OPG/ RANKL的表达率（P<0.05）。结论 不同浓度的α-玉米赤霉醇可以促进骨髓间充质干细胞向成骨细胞增殖、分化,并且通过上调OPG/ RANKL的表达率抑制成骨细胞细胞向破骨细胞分化,有望成为临床骨折疏松症治疗的激素替代药物。     

提踵运动对中老年人骨质改善程度的研究

目的 研究提踵运动对中老年人骨密度的改善情况。方法 以中老年人为研究对象,采用提踵运动对受试者的足跟给予应力剌激干预,以跟骨骨密度为主要参考指标,结合受试者的主观感受,经过3个周期的训练,对提踵试验组与对照组受试者的跟骨骨密度测试结果进行对比分析。结果 应力剌激对改善中老年男性的跟骨骨密度有一定帮助,提踵运动对于中老年男性跟骨骨密度的改善有较好的效果。女性对于应力剌激的阈值低于男性。结论 适宜负荷强度和频率的应力剌激,对改善处于骨质疏松情况下的中老年人跟骨骨密度有显著效果。     

特殊人群骨质疏松症研究进展

骨质疏松症是老年人常见的一种疾病,其最大的危害是增加了骨折的风险。随着人口的老龄化,骨质疏松性骨折的发病率也显著增高,引起了医学研究者的普遍关注。近年来许多研究表明骨质疏松的发生常与一些慢性疾病相关。本文通过分析强直性脊柱炎、慢性炎症、肾病综合征、精神分裂症及智力障碍这几类人群中骨质疏松症的研究进展,探讨骨质疏松症与这些疾病的关系。在以上几种疾病中,引起骨质疏松的因素包括：①TNF-a 和IL-6等炎症因子可通过抑制Wnt/β-catenin信号通路、引起OPG/RANKL/RANK系统平衡失调等途径产生一系列反应从而影响骨代谢,抑制成骨活动,促进破骨活动,加重骨质流失。②由于其他疾病引起的器官功能障碍影响导致钙、维生素D、雌激素等一些骨代谢相关因子的不足,使得成骨活动受到抑制,导致骨质疏松。③糖皮质激素、抗癫痫药物等影响了骨的代谢。④不良生活习惯、缺乏光照、缺少劳动锻炼、营养不良、体质指数下降等因素在骨质疏松的发生中同样扮演了重要的角色。综上所述,骨质疏松症的发生与多种因素相关,对于老年人,尤其是合并其他慢性疾病的老年人,应当加强骨密度的监测,早诊断,早治疗。