骨内型垂直向牙槽骨牵张器的研制

目的:研制骨内型牙槽骨牵张器,并在动物实验中检验其效果。方法:实验动物为成年杂种犬6只,实验材料为自行设计,纯钛制成的骨内型垂直向牙槽骨牵张器,直径3.75 mm,长5 mm。螺纹状钛种植体,直径3.75 mm,长度10 mm。先拔除犬的双侧下颌前磨牙,形成牙槽嵴萎缩模型。3月后随机选择一侧行骨切开术,植入两个牵张器。1周后开始牵张;2月后拆除牵张器,植入两枚螺纹钛种植体。3月后处死动物,取带种植体标本进行临床检查、放射学检查和扫描电镜检查。结果:骨内型垂直牙槽骨牵张器组织相容性良好,未发现有免疫排斥反应。牙槽骨高度平均增加(4.80±0.50)mm。植入后3月检查发现种植体和周围组织愈合良好,并与周围骨组织形成骨结合。结论:自行研制的骨内型牙槽骨牵张器取得良好的实验效果,为该器材的国产化和推广牙槽骨牵张成骨技术打下基础。     

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种植体与骨形成良好的骨结合界面是种植义齿修复成功的重要标志之一,而动物实验是评价种植体与骨结合界面的重要手段,其中犬牙槽骨是研究牙种植体植入的理想部位之一。本文就犬牙槽骨内植入种植体的实验方法及种植体与骨结合情况的评价方法做一综述。     

加载微种植体支抗对幼犬下颌骨生长发育的影响

目的:探讨加载微型种植体支抗对幼犬下颌骨生长发育的影响,为儿童正畸支抗的选择及设计提供参考.方法:拔除幼犬两侧下颌第一前磨牙,在下颌尖牙远中颊侧牙槽骨植入微种植体,采用200 g水平力加载于下颌尖牙及微型种植体间,对侧作为对照,采用相同大小的力加载于下颌尖牙与第一磨牙之间.在X线头颅侧位片上测量3个月后幼犬两侧牙槽骨垂直高度和下颌骨长度的变化.结果:暂时性加载的微种植体支抗牵尖牙向远中3个月后,幼犬牙槽骨高度的变化(p＞0.5)及下颌骨长度的变化(0.1＜p＜0.2),在统计学上都没有显著性差异.结论:暂时性加载的微型钛钉种植体对幼犬牙槽骨高度及下颌骨长度的发育基本无影响.提示青少年儿童应用微型种植体作支抗具有可行性.     

正畸微型种植体支抗稳定性的临床研究

目的：研究微型纯钛种植体承受正畸力后的稳定性。方法：16例安氏Ⅱ类上颌前突的女性成年患者,以植入于上领第二前磨牙与第一磨牙牙根之间牙槽骨的微型种植体作为支抗内收上前牙。种植体植入2周后加力,加力前及加力后9个月分别摄X线头颅定位侧位片,将加力前后的头颅定位侧位片进行重叠,测量微型种植体的移位变化。结果：16例中5例患者的微型种植体伸长并移位（-1．0～1．5mm）。所有微型种植体头部平均向前位移0．4mm,具有统计学意义（P〈0．05）。结论：微型种植体是一种稳定的支抗,但在承受正畸力后并不保持绝对的稳定,某些微型种植体在正畸力作用下会移位。为了防止其移位伤及邻近的重要组织,建议将微型种植体植入在无主要血管和神经通过的区域或植入在牙槽间隔区,必需使种植体与牙根之间保持2mm以上的安全距离。     

微型种植体在无牙颌患者覆盖义齿修复中的初步应用

目的探讨微型种植体在无牙颌患者修复中的临床初步应用。方法2002年5至8月，为4例全身健康情况不良伴牙槽骨重度吸收的无牙颌患者植入14枚微型种植体，磁性固位体覆盖义齿修复。术前、术后即刻、术后每年评估种植体周围皮质骨高度及周围牙龈健康状况，检查修复体戴用情况，评估患者满意度。结果14枚种植体至今全部存留，未发生种植体周围炎，X线片检查显示：种植体周围皮质骨高度稳定。除1枚下颌种植体磁性基台折断，余无异常。全部患者对修复体满意。结论利用微型种植体为无牙颌且伴有牙槽骨吸收的患者行覆盖义齿修复是可行的。本组随访3年的临床效果满意，长期效果尚待进一步观察。     

非潜入式植入法对平台转换连接种植体颈部牙槽骨吸收的影响

目的：评价非潜入式植入法对平台转换连接种植体颈部牙槽骨吸收有无影响。方法：23例共33颗后牙缺失患者按要求植入ankylos种植体,取出覆盖螺丝并上愈合基台。植入当天和二期修复时拍牙片并进行前后对比。结果：1枚种植体植入一周时出现异常予以拔除,其余种植体均能形成良好的骨结合。经牙片对比,植入当天与二期修复时种植体颈部牙槽骨无明显变化。结论：非潜入式植入法对平台转换连接种植体颈部牙槽骨吸收无明显影响。     

纳米羟磷灰石/聚酰胺-66牙种植体的动物试验

目的 探讨纳米羟磷灰石,聚酰胺-66(nHA/PA-66)复合牙种植体的动物试验结果及临床可行性.方法 将 nHA/PA-66复合牙种植体随机植入5只成年杂种犬前牙区新鲜拔牙创内,定期处死动物,获取其上下颌骨标本,进行局部X线和苏木精-伊红染色检查.结果 术中共拔除前牙23颗,植入种植体13枚,术后除1枚于8周时脱落外,其余种植体良好存在.种植体与牙槽骨间间隙无明显增宽或变窄,间隙内有结缔组织形成且随时间延长逐渐增多、排列方向发生改变.结论 nHA/PA-66种植体植入犬新鲜拔牙创后,在种植体与牙槽骨间可 形成随时间推移数量增多、排列改变的结缔组织.这些结缔组织到底是种植体周围的纤维包裹还是来源于拔牙创内的健康牙周膜,有待进一步研究.     

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。     

种植体植入后牙槽骨破骨细胞的活性变化

目的:动态观察种植体植入后不同时间段周围牙槽骨破骨细胞的数目、活性的表达变化规律.方法:选用6只成年雄性Beagle犬作为实验动物,随机选择双侧下颌第二前磨牙及第四前磨牙共计24个牙位,分别以12个牙位作为实验组和对照组,检侧种植体植入后3、7、15、30、60和90 d种植体周围牙槽骨破骨细胞的活性变化.取犬下颌骨进行大体标本观察,拍摄X线片,取种植体周围骨组织进行HE染色,观察破骨细胞的形态学变化,并进行定量组织学分析,对照组拔牙窝的检测方法相同.采用SPSS13.0软件包对数据进行统计学分析.结果:破骨细胞的表达活性在种植体植入后第7天达到高峰,而后随时间延长逐渐降低,实验组破骨细胞的活性表达显著活跃于对照组.结论:破骨细胞性骨吸收最为活跃的时间在种植体植入后的第7天左右.     

微型支抗种植体即刻加载的组织学研究

目的研究微型支抗种植体即刻加载的界面愈合情况。方法微型支抗种植体植入犬下颌骨,施以200 g水平力,定期注射荧光标志物,73 d后处死动物,制作种植体-骨标本切片,进行光镜、荧光镜、偏光镜、软X线片、扫描电镜等观察及X线能谱分析。结果种植体周围形成良好的骨性结合,动态荧光标记显示植入6周时有板层骨形成,9周时板层骨显著。结论微型种植体植入后即刻可承载200 g正畸力而不影响其骨性愈合过程。     

含氟羟基磷灰石涂层对正畸微种植体骨结合及周围炎的影响

目的:探讨含氟羟基磷灰石涂层(FHA)钛合金及钛合金正畸微种植体对骨结合及种植体周围炎的影响.方法:将微种植体植入兔下颌前磨牙区颊侧牙槽骨,扫描电镜观察骨结合状态,ELISA检测龈沟液中肿瘤坏死因子-α(TNF-α)含量.结果:FHA涂层组比钛合金组骨密度更致密,骨髓腔更小.炎症诱发前后钛合金组TNF-α水平较高,持续时间较长(P＜0.05).结论:FHA涂层钛合金微种植体的骨组织相容性较好,对种植体周围炎起到一定的抑制作用.     

Effect of tetracycline on gingival inflammation and alveolar bone resorption n beagles: An individual tooth by tooth analysis

Abstract The effect of systemic tetracycline on gingival inflammation and alveolar bone resorption was studied in beagle dogs. Seventeen dogs were divided into three groups receiving either no treatment, 250 mg tetracycline HO, or 500 mg tetracycline HC1 daily. The severity of gingival inflammation and activity of alveolar bone resorption during a 6-month pretreatment period was compared to a 24-month treatment period for each individual tooth studied. In the first 12 months of treatment there was a significant decrease in the severity of gingival inflammation and the activity of alveolar bone loss in the tetracycline treated dogs. By 24 months of treatment increased gingival inflammation and rate of bone loss was evident in the treated dogs. In the untreated control dogs there was a statistically significant association between the severity of gingival inflammation and activity of alveolar bone resorption about the teeth studied. In the tetracycline treated dogs, no such association existed.     

Tetracycline treatment of periodontal disease in the beagle dog

Seventeen adult beagle dogs with moderate to severe periodontitis were examined at time zero and after a 6 month pretreatment period for plaque accumulation, gingival inflammation, and rate of alveolar bone loss. The dogs were then divided into three groups. One group was the untreated controls, one group received tetracycline HCl 250 mg daily, and one group received tetracycline HCl 500 mg daily. Plaque accumulation, gingival inflammation, and rate of alveolar bone loss in each group over a 12 month treatment period was compared to the pretreatment baseline values in each group.
There was no significant difference in either the mean plaque accumulation or gingival inflammation over the 12 month treatment period in the untreated control dogs or the tetracycline treated dogs. The untreated control dogs lost alveolar bone in the treatment period at a rate similar to the pretreatment period. In the dogs treated with 250 and with 500 mg tetracycline HCl there was a statistically significant decrease in the rate of alveolar bone loss in the treatment period when compared to the pretreatment period.
The findings suggest that daily tetracycline in either a 250 or 500 mg dose does not affect accumulation of bacterial plaque or severity of gingival inflammation in the beagle dogs studied. Tetracycline administration does significantly decrease the rate of alveolar bone loss in the treated animals for a 12 month period. An additional report will detail the subsequent 12 months of treatment in which tetracycline loses its ability to reduce the rate of alveolar bone loss.     

Location of proliferating gingival cells following toothbrushing stimulation

OBJECTIVES: Mechanical stimulation by toothbrushing promotes healing of gingivitis through accelerating cell proliferation. Junctional epithelium proliferates at periodontal pocket formation. A question is arisen whether toothbrushing contributes to the repair of gingival inflammation or deterioration of pocket formation. The location of proliferating cells in gingiva stimulated mechanically by toothbrushing was investigated. MATERIALS AND METHODS: A total of 24 teeth of dogs underwent daily plaque removal with a curette (plaque removal) or both plaque removal and toothbrushing (toothbrushing). Proliferative activity of gingival cells in six individual zones was evaluated by assaying expression of proliferating cell nuclear antigen (PCNA). RESULTS: Toothbrushing increased densities of PCNA-positive basal cells in the junctional epithelium, connective tissues adjacent to the junctional epithelium, the alveolar bone of the oral epithelial side and the oral epithelium. However, the densities of PCNA-positive cells at the apical portion of the junctional epithelium, connective tissues adjacent to the cementum and the alveolar bone of the periodontal ligament side did not increase following toothbrushing. CONCLUSIONS: Toothbrushing promotes proliferation of gingival cells other than fibroblasts in periodontium and basal cells in the apical portion of the junctional epithelium. The repair of periodontal tissues might be promoted by toothbrushing within the limit of the direct mechanical stimulation.     

Inhibitory effects of YM175, a bisphosphonate,on the progression of experimental periodontitis in beagle dogs

This study examined the efficacy of YM175 [disodium dihydrogen (cycloheptylamino) methylene-1,1-bisphosphonate] in reducing alveolar bone loss caused by experimental periodontitis in beagle dogs. Thirty-six dogs were used and divided into 6 groups. Periodontitis was induced in 30 dogs (groups 2-6) by ligating the bilateral mandibular third and fourth premolar teeth with silk ligatures and by feeding a soft diet. Six dogs were sham-operated (group 1). Saline (placebo), flurbiprofen (0.02mg/kg) and YM175 (0.01, 0.1 and 1.0 mg/kg) were administered to the dogs (groups 2-6) 5 d/wk for 25 wk. Radiographic and morphometric analyses were performed. In placebo-treated animals (group 2), the ligation caused a significant decrease in the alveolar bone height by 0.57 and 1.91 mm at 2 and 25 wk, respectively. YM175 (1.0 mg/kg) prevented the decrease in bone height by 47 and 31% at 2 and 25 wk. YM175 (0.1 mg/kg) and flurbiprofen tended to prevent bone loss after 15 wk. Although the ligation elicited no significant change in bone mineral density, it significantly decreased bone volume. YM175 (1.0 mg/kg) and flurbiprofen tended to increase the bone volume. The number of formative or resorptive Haversian canals and the bone turnover through the periosteal bone surface were increased by the ligation, indicating the increased turnover of the cortical bone. YM175 (1.0 mg/kg) reduced the increased bone turnover. The gingival index was maximally increased at 2 wk and was suppressed by YM175. These results suggest that YM175 prevents alveolar bone loss by reducing the increased alveolar bone turnover in dogs with periodontitis.     

Inhibitory effects of YM175, a bisphosphonate, on the progression of experimental periodontitis in beagle dogs

This study examined the efficacy of YM175 [disodium dihydrogen (cycloheptylamino) methylene-1,1 -bisphosphonate] in reducing alveolar bone loss caused by experimental periodontitis in beagle dogs. Thirty-six dogs were used and divided into 6 groups. Periodontitis was induced in 30 dogs (groups 2–6) by ligating the bilateral mandibular third and fourth premolar teeth with silk ligatures and by feeding a soft diet. Six dogs were sham-operated (group 1). Saline (placebo), flurbiprofen (0.02mg/kg) and YM175 (0.01, 0.1 and 1.0 mg/kg) were administered to the dogs (groups 2–6) 5 d/wk for 25 wk. Radiographic and morphometric analyses were performed. In placebo-treated animals (group 2), the ligation caused a significant decrease in the alveolar bone height by 0.57 and 1.91 mm at 2 and 25 wk, respectively. YM175 (1.0 mg/kg) prevented the decrease in bone height by 47 and 31% at 2 and 25 wk. YM175 (0.1 mg/kg) and flurbiprofen tended to prevent bone loss after 15 wk. Although the ligation elicited no significant change in bone mineral density, it significantly decreased bone volume. YM175 (1.0 mg/kg) and flurbiprofen tended to increase the bone volume. The number of formative or resorptive Haversian canals and the bone turnover through the periosteal bone surface were increased by the ligation, indicating the increased turnover of the cortical bone. YM175 (1.0 mg/kg) reduced the increased bone turnover. The gingival index was maximally increased at 2 wk and was suppressed by YM175. These results suggest that YM175 prevents alveolar bone loss by reducing the increased alveolar bone turnover in dogs with periodontitis.     

微型种植体-牙联合支抗牵张成骨在牙槽突裂治疗中的应用

目的：探讨微型种植体-牙联合支抗牵张成骨治疗牙槽突裂的可行性,以及微型种植体对支抗牙的影响。方法：成年杂种犬14只,随机分为A、B、C3组,A、B每组6只,C组2只为对照组。首先形成牙槽突裂外科模型,2周后手术截骨,形成一含牙的骨输送盘。A组采用单纯牙支抗的方法,B组采用微型种植体-牙联合支抗的方法,C组骨切开后原位固定。1周后开始牵引,牵张完成后固定1个月,处死全部动物,取标本作大体观察、组织学检查,应用SPSS10.0软件包对2组数据分别作Fisher准确性检验和t检验。结果：2种方法均能关闭牙槽突裂隙。2组犬的阳性数比较有显著性差异（P〈0.05）。A、B2组支抗牙在骨输送盘中的移动量具有显著性差异（P〈0.01）。结论：微型种植体-牙联合支抗牵张成骨治疗牙槽突裂是可行性的,使用微型种植体,可以减轻支抗牙牙周-牙髓组织的损伤,减少支抗牙的倾斜移位。     

Formation of new periodontal attachment apparatus after experimental root isolation with collagen membranes in the dog.

This study evaluated the ability of collagen membranes to act as biodegradable barriers that interfere with colonization of the root surface by gingival cells and allow selective repopulation of the denuded root surface by periodontal ligament-derived tissue. Over a 3-year period, experimental and control surgical procedures were performed on canine teeth in six beagle dogs and on premolars in three beagle dogs. Results showed that the membranes partially prevented apical migration of epithelium during healing. Regeneration of new cementum, alveolar bone, and periodontal ligament-like tissue was found in the studied premolars but notably absent on the canines.     

壳聚糖修饰的羟基磷灰石-磷酸三钙修复犬牙槽骨缺损的实验研究

目的：研究经壳聚糖（Chitosan,CS）修饰的羟基磷灰石-磷酸三钙（hydroxyapatite-tricalcium,HA-TCP）复合材料修复犬牙槽骨缺损。方法：制备CS溶液修饰HA-TCP。以CS修饰的HA-TCP复合材料修复犬牙槽骨缺损,选取3只成年犬876︱678作为受试牙,在受试牙根分歧处制备长宽高均为5mm的箱型骨缺损,分成两组,左侧作为实验组：将CS修饰的HA-TCP复合材料植入犬牙槽骨缺损部位;右侧作为对照组：将HA-TCP植入犬牙槽骨缺损部位;植入8周后将实验动物处死,组织学观察并图像分析新生骨组织的形成状态。结果：实验组新生骨组织占缺损的百分比明显高于对照组,有统计学意义（P〈0.01）;实验组剩余材料占缺损的百分比小于对照组,有统计学意义（P〈0.01）。结论：CS修饰后的HA-TCP复合材料修复犬牙槽骨缺损效果优于单纯HA-TCP修复牙槽骨缺损。     

Cem-Ostetic修复牙种植体颊侧骨缺损的初步实验观察

目的:探讨Cem-Ostetic(骨速刚)修复牙种植体颊侧骨缺损的可行性.方法:拔除3只犬双侧下颌第二、三、四前磨牙,每侧即刻植入3颗种植体,并在种植体颊侧骨壁制造3 mm×3 mm×2 mm缺损.暴露种植体,由近中向远中依次植入Bio-Oss骨粉、磷酸钙骨水泥、Cem-Ostetic骨浆.种植术后4、8、12周各处死...