成骨诱导剂对拔牙创愈合的影响

目的 探讨以明胶海绵为载体,地塞米松、维生素C和β-甘油磷酸钠组成的成骨诱导剂对拔牙创愈合和牙槽嵴形态改建的影响。方法选用50只家兔,拔除双侧上颌第一前磨牙,右侧拔牙创内填入载有成骨诱导剂的明胶海绵,作为实验侧;左侧填入空载明胶海绵,作为对照侧。拔牙后第1、2、4、8、12周各处死10只动物,取双侧牙槽骨标本,拍摄X线片,并测量骨缺损区新骨密度;用组织学方法评价拔牙创愈合情况;并于12周时,测量拔牙区牙槽嵴高度吸收值。结果X线片骨密度测量显示：术后2、4、8、12周,实验侧骨密度值均高于对照侧,差异有统计学意义（P<0.01）。组织学检查显示：实验侧拔牙创内成骨现象较对照侧早,成骨细胞分化和增殖更活跃。
12周时实验侧牙槽嵴高度吸收值小于对照侧,差异有统计学意义（P<0.01）。结论 由地塞米松、β-甘油磷酸钠和维生素C组成的成骨诱导剂能促进拔牙创愈合,加速成骨和骨改建。     

小型猪拔牙创愈合的组织学研究

目的了解小型猪拔牙窝愈合的基本特征,观察愈合过程中成骨细胞及破骨细胞的分布规律。方法拔除小型猪相邻的两颗前磨牙,分别于拔除后即刻、4、7、14、30及60天处死动物,获取标本后脱钙,制作组织切片,HE染色,光镜观察不同时间点的拔牙窝组织学变化。采用Image-ProAnalyzer 7.0图像分析系统对颊、舌侧骨板的成骨、破骨细胞进行计数分析。结果拔牙后第4天拔牙窝底部可见较多的破骨细胞;拔牙后第7天骨板内外侧已经有类骨质形成,破骨细胞向方迁移;拔牙后第14天成骨活动十分活跃,仅舌侧骨板还可观察到少量破骨细胞;拔牙后30天拔牙窝内已充满板层骨,哈弗氏系统丰富;60天后拔牙窝内组织学形态接近正常牙槽骨。结论小型猪拔牙窝愈合过程中组织学特征与人类及其它种属相似,但愈合速度更接近人类,小型猪是研究拔牙窝愈合及牙槽突改建较理想的动物模型。     

高植入扭力对微型种植体-骨界面愈合的组织学影响

目的:探讨高植入扭力对种植体-骨界面组织愈合的影响。方法:将36枚微型种植体以(14±1)Ncm及(11±1)Ncm的扭力植入4只Beagle犬的下颌牙槽骨,观察7 d及28 d的组织学、组织形态测量学及扫描电镜变化。结果:14 Ncm组植入后7 d界面密骨质有重度微损伤,28 d骨界面仍有许多碎骨屑。而11 Ncm组7 d骨质轻度微损伤,28 d骨愈合良好。2组种植体-骨结合率(BIC)无显著差异(P0.05),7 d时,2组种植体-骨密度(BD)值差异无统计学意义(P0.05),但28 d时,11 Ncm组BD值明显高于14 Ncm组(P0.05)。结论:适度扭力植入种植体的骨界面损伤小、愈合快,而过高植入扭力可造成骨界面严重微损伤,影响骨组织愈合。     

种植体骨结合与拔牙创愈合时间的相关性实验研究

目的：研究拔牙后创口愈合时间对种植体骨结合的影响,探讨拔牙后最佳种植体植入时间。方法：在拔除家犬的下颌双侧第二三前磨牙后不同时间植入种植体,3个月后处死动物观察种植体与拔牙窝之间新骨生成情况及密度并测量骨接触率。结果：0周组与3周组、6周组、9周组比较,差异有统计学意义（P〈0.05）,0周组的骨接触率明显低于3周组、6周组和9周组。3周组与9周组、6周组与9周组之间亦有非常显著性差异（P〈0.05）。6周组的骨接触率略高于3周组,但统计学分析无显著性差异（P〉0.05）。结论：在种植手术3个月时,即刻种植的骨接触率最低,拔牙3周、6周时种植的骨接触率无明显差异,拔牙后3周种植即能在短期内达理想骨结合。     

芹黄素对拔牙创早期骨愈合影响的实验研究

目的 芹黄素是一种广泛分布的植物类黄酮,本研究通过动物实验,探讨芹黄素对于拔牙创早期骨愈合的影响。方法 选取24只8周Wistar雄性大鼠,将其随机分为低剂量组、高剂量组、对照组3组,拔除右上颌第一磨牙,腹腔注射芹黄素溶液（10mg/kg、50mg/kg、0mg/kg）,每两天注射一次。在拔牙后28天处死全部大鼠,分离右上颌骨,进行Micro CT扫描及制作石蜡切片。切片行HE染色和OPG、RANKL免疫组织化学染色。采用Prism 7.0软件包对数据进行统计学分析。结果 HE染色及Micro CT扫描显示加药组拔牙创愈合程度优于对照组。芹黄素可以促进OPG的表达(P<0.05）,同时降低RANKL的表达（P<0.05）。结论 芹黄素对于大鼠拔牙创早期的骨愈合具有促进作用。     

骨形成蛋白复合骨拔牙创种植的实验研究

本实验用骨形成蛋白（BMP）复合陶瓷化牛骨（CeramicBovineBone，CBB）种植于狗的拔牙创内，通过大体观察、组织学切片及X线显微分析等方法，对比观察了BMP复合骨和单纯陶瓷化骨在拔牙创愈合过程中的作用。实验结果表明BMP复合骨的骨诱导性、成骨效率及骨成熟程度明显优于单纯陶瓷化骨，起到了促进拔牙创愈合，防止牙槽骨吸收萎缩的作用。     

锂盐对大鼠拔牙创愈合的影响

目的:观察锂盐对大鼠拔牙创愈合过程中新骨形成的影响。方法:取20只Wistar大鼠,拔除左侧上颌第二磨牙,随机分为2组。实验组从拔牙前7d起至拔牙后第3天每天腹腔注射LiCl,对照组给予相同剂量NaCl。拔牙后3d、7d处死大鼠。通过HE染色定量分析新骨的形成,BrdU标记增殖细胞。采用Image-Pro Plus生物图像分析系统对增殖细胞及新骨量作半定量分析,应用SPSS 13.0软件包对数据进行统计学分析。结果:拔牙后3d,拔牙创内间充质细胞增殖,实验组细胞增殖明显,BrdU阳性细胞数为对照组的1.8倍,两者有显著差异(P<0.05)。拔牙后7d,拔牙创底部新生骨小梁生成,相对新骨量实验组为27.0%±6.5%,对照组为12.7%±5.1%,实验组与对照组有显著差异(P<0.01)。结论:在大鼠拔牙创愈合中,前期给予锂盐可促进间充质细胞增殖,使新骨形成增加。     

药物对拔牙创愈合的影响

拔牙后的组织学改变包括早期拔牙创的愈合及随后牙槽嵴的改建,这一过程受到一系列全身和局部因素的影响。本文将就近年来有关局部或全身用药对拔牙创愈合和牙槽嵴改建的研究作综述,这将帮助我们预计不同患者拔牙创的愈合情况,也将对将来运用药物主动干预这一过程有所帮助。     

BMP复合陶瓷化骨促进拔牙创愈合的实验研究

ＢＭＰ复合陶瓷化骨促进拔牙创愈合的实验研究周建中１刘宝林２任昭魁１（１国防科工委五一四医院口腔科２第四军医大学口腔医学院）～～～～～～～～～～～～～～～～～～～～本实验将具有高效骨诱导作用的骨形成蛋白（ＢｏｎｅｍｏｒｐｈｏｇｅｎｅｔｉｃＰｒｏｔｅｉｎ...     

内源性甲状旁腺激素对于小鼠拔牙创骨愈合影响的研究

目的 探讨内源性甲状旁腺激素(parathyroid hormone,PTH)对小鼠拔牙创骨愈合的影响。方法 选用PTH基因敲除小鼠(PTH-/-)和野生型小鼠(PTH+/+)各18只,拔除小鼠双侧上颌第一磨牙,拔牙后第7、14、21天分3批处死小鼠,并通过苏木精-伊红染色、骨总胶原染色、耐酒石酸酸性磷酸酶染色方法进行组织学观察。结果 组织学结果显示,与野生型小鼠相比,PTH基因敲除的小鼠拔牙创骨小梁纤细,排列不规则,骨量少,拔牙创愈合延迟,骨面上破骨细胞总长度占骨面长度的百分比降低。结论 内源性PTH缺少可以影响小鼠拔牙创愈合。?     

非甾体类抗炎药对种植体周围骨愈合和骨改建的影响

牙种植的成功首先取决于种植体的骨整合,而良好的骨整合受诸多因素的影响。非甾体类抗炎药(NSAID)除用来治疗骨关节系统的慢性炎症性疾病之外,还常用于控制种植手术后的疼痛不适。NSAID通过抑制环加氧酶的活性来减少地诺前列酮的合成,进而影响种植体骨整合和骨改建过程中新骨的形成。本文就NSAID对成骨细胞、骨愈合和种植体周围成骨的作用等研究进展作一综述。     

TM种植体-骨结合界面的显微CT观察

目的 研究TM种植体-骨结合界面及其上 1/3倒楔形间隙的成骨情况.方法 用医用钝钛钛棒加工成两组种植体,实验组为锥度5.44°、表面进行喷砂酸蚀处理的TM种植体,锥度从种植体上1/3处开始变化;对照组为仿straumann的表面喷砂酸蚀(sandblast large grit and acid-etching,SLA)圆柱状螺纹种植体.建立Beagle犬下颌骨种植模型,3只犬每只植入实验组TM种植体和对照组仿straumann -SLA圆柱状螺纹种植体各4枚,3只实验犬分别于4周、8周和12周处死,截取下颌骨行显微CT三维重建,观察种植体-骨结合界面及上1/3间隙的成骨情况.结果 8周时实验组TM种植体上1/3倒楔形间隙开始有骨修复,12周时对照组仿straumann-SLA种植体颈部骨质有吸收迹象,实验组TM种植体颈部骨质仍得到良好保存.结论 TM种植体能形成良好骨结合界面,体部上1/3的锥度设计可保存颈部皮质骨.     

种植体骨界面组织形态学研究方法探讨

目的:探讨利用Leitz-1600型锯割切片机及骨磨片技术进行种植体骨结合状况的组织学研究方法.方法:选取植入种植体的颌骨或其他部位的骨组织,经过X线定位、塑料包埋、锯割切片机分切、手工磨片及特殊染色等组织学手段,考察种植体骨结合情况,以及植入骨再生材料的成骨情况.结果:植入种植体的骨组织经过完善的组织学处理后,采用手工磨片可以磨制30μm～50μm的骨种植体磨片,并能清楚地观察到种植体骨结合的状况,以及骨再生材料成骨的变化过程.结论:塑料包埋,手工磨片,以及特殊染色等组织学方法,可以成为研究种植体骨结合及其他与种植体相关研究的重要手段.     

Bone tissue formation adjacent to implants placed in fresh extraction sockets: an experimental study in dogs

OBJECTIVE: To study the healing of marginal defects that occurred at implants placed in a healed ridge or in fresh extraction sockets. MATERIAL AND METHODS: Six dogs were used. The right side of the mandible was used in the first part of the study. The first, second premolars and first molars were extracted. After 3 months of healing the bone was prepared for implant installation in these premolar and molar sites. The marginal 5 mm of each recipient site was widened with a conical drill. Following implant installation a gap of varying dimension occurred around the titanium rod (artificial defect (A) sites). At this interval the third and fourth premolars were extracted and implants were installed in the distal socket of the two teeth (natural defect (N) sites). The flaps were sutured to allow non-submerged healing. After 2 months, the procedures were repeated in the left side. Two months later the animals were euthanized, and biopsies were obtained and prepared for histological examination. RESULTS: The length of the zone of de novo'bone-to-implant contact' in the defect region was longer at the A sites than at the N sites both at the 2- and the 4-month interval. Further, while after 4 months of healing the marginal bone crest at the A sites was located close to the abutment/fixture junction, at the N sites a marked reduction of the height of the bone crest was documented. Hence, most A site defects became completely resolved whereas healing of the N site defects was incomplete. CONCLUSION: The process of bone modeling and remodeling at an implant placed in a fresh extraction socket differs from the resolution of marginal defects that may occur following implant installation in a healed ridge.     

Influence of a microgrooved collar design on soft and hard tissue healing of immediate implantation in fresh extraction sites in dogs

Objective: This study compared the alveolar bone reduction after immediate implantation using microgrooved and smooth collar implants in fresh extracted sockets. Material and methods: Four mongrel dogs were used in this study. The full buccal and lingual mucoperiosteal flaps were elevated and the third and fourth premolars of the mandible were removed. The implants were installed in the fresh extracted sockets. The animals were sacrificed after a 3‐month healing period. The mandibles were dissected and each implant site was removed and processed for a histological examination. Results: During healing, the marginal gaps in both groups, which were present between the implant and the socket walls at implantation, disappeared as a result of bone filling and resorption of the bone crest. The buccal bone crests were located apical of its lingual counterparts. At the 12‐week interval, the mean bone–implant contact in the microgrooved group was significantly higher than that of the turned surface group. From the observations in some of the microgrooved groups, we have found bone attachment to the 12 μm microgrooved surface and collagen fibers perpendicular to the long axis of the implants over the 8 μm microgrooved surface. Conclusion: Within the limitations of this study, microgrooved implants may provide more favorable conditions for the attachment of hard and soft tissues and reduce the level of marginal bone resorption and soft tissue recession. To cite this article:
Shin S‐Y., Han D‐H. Influence of microgrooved collar design on soft and hard tissue healing of immediate implantation in fresh extraction sites in dogs.
Clin. Oral Impl. Res. 21 , 2010; 804–814.
doi: 10.1111/j.1600‐0501.2010.01917.x     

Load-related bone modelling at the interface of orthodontic micro-implants

Abstract: The purpose of this study was to determine the interface reaction of two different titanium micro‐implant systems activated with different load regimens. A total of 200 micro‐implants (100 Abso Anchor^® and 100 Dual Top^®) were placed in the mandible of eight Göttinger minipigs. Two implants each were immediately loaded in the opposite direction by various forces (100, 300 or 500 cN) through tension coils. Three different distances between the neck of the implant and the bone rim (1, 2, 3 mm) were used. The loads provided by superelastic tension coils (which are known to develop a virtually constant force) led to a range of tip moments 0–900 cN mm at the neck of implants. Non‐loaded implants were used as a reference. Bone tissue responses were evaluated by histology, histomorphometry and scanning electron microscopy after 22 and 70 days of loading. Implant loosening was present in the groups where the load reached 900 cN mm. No movement of implants through the bone was found in the experimental groups, for any of the applied loads. A direct bone‐to‐implant contact to various extents was observed at differently loaded implants. Ultrastructural analysis confirmed the clinical and histological finding that implants (except when loaded at 900 cN mm) were well osseointegrated after 22 days. An increase in the bone‐to‐implant contact ratio was observed during the experimental period in the coronal part of the implants in most experimental groups. The difference reached a level of statistical significance at 500 cN mm (Abso Anchor^®) and 600 cN mm (Dual Top^®). We conclude that micro‐implants can not only be loaded immediately without impairment of implant stability but many enhance bone formation at the interface when the load‐related biomechanics do not exceed an upper limit of tip moment at the bone rim.     

皮质骨厚度对支抗种植体-骨界面应力分布的影响

目的：研究皮质骨厚度改变对支抗种植体-骨界面应力分布的影响，供临床参考。方法：用三维有限元方法，对分别种植于皮质骨厚度为0．5mm、1．0mm、2．0mm颌骨模型中的种植体施加150g近远中方向的载荷，分析支抗种植体-骨界面应力分布情况：结果：三者种植体颈部的Von-Mises应力值分别为0．6040MPa、0．5330MPa、0．5380MPa；位移值分别为0．2110μm、0．1630μm、0．1250μm：结论：皮质骨在一定厚度内，植入体颈部皮质骨越薄，骨界面应力值就越大：但皮质骨超过一定厚度后，骨界面应力并不随其厚度的增加而做相应递减。皮质骨的厚度与界面骨的位移成反比.     

Early healing of implants placed into fresh extraction sockets: an experimental study in the beagle dog. De novo bone formation

Objectives: Describe the early phases of tissue integration in implants placed into fresh extraction sockets and test whether a new implant surface nano‐topography (DCD nano‐particles, Nanotite^?) promotes early osseointegration when compared with minimally rough surface implants (DAE, Osseotite^®). Material and Methods: Sixteen beagle dogs received 64 test and control implants randomly installed into the distal socket of ₃P₃ and ₄P₄. Histomorphometric analysis of bone to implant contact (BIC) and bone area was performed at 4 h, 1, 2, 4 and 8 weeks. Results: Wound healing initiated with a coagulum that was substituted by a provisional matrix at 1 week. Bone formation started concomitant to a marked bone resorption. At 2 weeks, woven bone formation was evident and gradually remodelled into lamellar bone at 4 and 8 weeks. BIC increased similarly throughout the study in both groups with a tendency to higher percentages for the test devices at 2 and 4 weeks. The influence of the DCD nano‐particles was more evident at the fourth premolar site. Conclusion: Osseointegration occurred similarly at both implant groups, although the socket dimension appeared to influence bone healing. It is suggested that the enhanced nano‐topography has a limited effect in the immediate implant surgical protocol.