羟磷灰石人工牙根对狒狒种植的评价

本文的目的是研究人工牙根种植能否成功地防止齿槽嵴吸收。材料和方法:以6只狒狒作为实验对象,拔除下颌骨侧切牙和第2双尖牙,立刻将羟磷灰石人工牙根种植到牙槽窝内。人工牙根为牙槽窝深度的1/2,一侧植入到底部,另一侧只堵住牙槽窝口。侧切牙处植入一个人工牙根,第2双尖牙处按近远中根分别植入(单根除外)。植入的人工牙根均要求在齿     

保留颊侧部分牙根对牙槽窝改建影响的动物研究

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。     

羟磷灰石牙根复制品植入后疗效现察

随着人们寿命增长,无牙颌人口逐渐增多,保持无牙颌者牙槽骨高度显得更重要。口腔医师制作一种既有组织相容性,又不引起吸收的羟磷灰石牙根复制品代替拔除牙根,在防止牙槽骨进一步吸收方面取得很大成就。本文作者主要观察羟磷灰石牙根复制品植入的位置与成功率关系。材料和方法作者对21名拔除下颌牙齿,并立即戴义齿患者进行了研究。治疗经过:仔细拔除下颌牙齿,尽量不损伤牙槽骨,骨尖磨平,不需邻近软组织瓣覆盖。拔牙后用牙槽尺测量牙槽窝高度,选择合适无菌的羟磷灰石牙报复制品植入,用木锤将牙根复制品牢固固定在牙槽窝内,使它位于牙槽嵴下2mm～3mm,缝合牙龈,将预成义齿立即戴上,进行咬合词整。术后嘱患者     

脱位牙再植的远期临床观察

脱位牙再植的远期临床观察兰州军区乌鲁木齐总医院口腔科（８３００００）刘金忠，李旭自体脱位牙再植术是指将因受外伤打击或外科手术时意外损伤造成的牙体牙根完整、牙周膜保存完好、牙槽窝损伤不大、骨壁良好、无严重骨折的患者的脱位牙齿重新植入原来牙槽窝内的一种手...     

牙撕脱性损伤延迟再植的根面处理

牙撕脱性损伤是指在外力的突然作用下,牙齿完全脱出牙槽骨,牙周膜和牙髓同时损伤,牙槽窝变得空虚或伴有牙槽突的骨折。对牙撕脱性损伤的理想治疗方案是将撕脱牙即刻再植入牙槽窝,以保持附着在牙根表面牙周组织的活性。根面处理是指用药物浸泡或覆盖牙根表面,     

前牙根折粘接再植短期效果观察

目的：评价前牙外伤牙根折断后再接再植术的短期临床效果。方法：用0．9mm或1．0mm钢丝作根管桩,以GCFuji Ⅱ玻璃离子为粘接剂和倒充剂,将17颗前牙牙根折断患牙断根再接,植入原牙槽窝内,钢丝固定1个月。结果：经过3年随访,1颗脱落,其余16颗生长稳固,随访期内未发现有牙根吸收。结论：断牙再接再植后在牙槽窝生长稳固,色泽美观,能发挥大部分咀嚼功能。     

自体牙移植改良术式临床分析

目的:分别比较自体前牙及后牙移植于经种植手术器械处理人工牙槽窝和已有牙槽窝的临床疗效。方法:选取下颌前牙缺失26例,残根30例;下颌第一磨牙缺失32例,残根、残冠38例。使用超声骨刀去骨拔出自体埋伏牙、异位牙和下颌第三磨牙,植入使用口腔种植器械规范预备好的牙槽窝内;使用直丝弓托槽及个性化弓形圆钢丝固定4周。前牙2周行根管治疗,后牙植入前完成根管治疗。结果:前牙除人工牙槽窝分组1例因松动拔除外,其余随访2年,均稳固且功能正常;后牙除已有牙槽窝分组1例松动脱落外,其余随访2年,均稳固且功能正常。结论:自体前牙及后牙移植于已有牙槽窝和人工牙槽窝均能获得良好稳固性和咀嚼功能,但在远期效果方面,自体下颌前牙移植于已有牙槽窝优于人工牙槽窝;自体下颌后牙移植于人工牙槽窝优于已有牙槽窝。     

下前牙脱位7d再植成功1例

患者男 ,2 8岁 ,农民。因跌倒致牙外伤 7ｄ来诊。检查 :下唇擦伤处已结痂 ,42、41冠部缺失 ,残余根位于龈下 2ｍｍ ,31缺失 ,牙槽窝内见机化血凝块。 43、32未见异常。Ｘ线片示 :42、41残根部未见折痕 ,31牙槽窝空虚 ,未见牙槽骨骨折。嘱患者找回缺失的 31牙。见 31牙体干燥 ,根部残余牙周膜已失水坏死。将患牙置于生理盐水中 30ｍｉｎ ,轻轻刮除残余坏死的牙周膜 ,常规行根管治疗后置于庆大霉素和地塞米松液中 1ｈ ,无菌条件下局麻后刮除牙槽窝内的机化血凝块 ,用庆大霉素和地塞米松液冲洗牙槽窝 ,将脱位牙植入牙槽窝内 ,将 31～ 34用钢丝…     

Bio-oss/rhBMP-2复合体修复异种再植牙周围骨缺损的实验研究

目的:评价Bio-oss人工骨与重组人骨形成蛋白-2(rhBMP-2)复合体修复异种再植牙周围骨缺损的效果。方法:拔除3只普通狗下颌第3前磨牙,扩大牙槽窝,造成颊舌侧牙槽骨完全缺损,将临床拔除的锥形多生牙根、经Ca(OH)2根充并干燥植入后,在牙根周围缺损区植入Bio-oss/rhBMP-2复合体,术后2、3个月通过X线影像学、硬组织切片进行组织形态学定性分析。结果:2个月时,骨缺损区新骨逐渐开始替代Bio-oss并钙化,新骨与再植牙根面和基骨形成骨性结合;3个月时新生骨骨小梁的面积(B.Ar)增加,骨小梁周长(B.Pm)减小(P<0.05),骨小梁厚度增大,未完全降解的Bio-oss颗粒被逆根向转移。结论:Bio-oss/rhBMP-2复合体可有效促进再植牙周围骨缺损区骨组织再生,并促使牙根与牙槽骨形成根-骨结合。     

羟基磷灰石种植体的动物实验研究

分别在兔子左下切牙远端人工制备牙槽窝,植入羟基磷灰石生物陶瓷种植体,分别于1、3、6个月处死兔子,制成标本在光镜及电镜下观察。种植体与骨组织1个月时为纤维性结合;3个月时大部分为骨性结合,少部分为纤维性结合;6个月时为骨性结合,有较多骨组织长入种植体内。另再拔除兔子上前牙,即刻将种值体植入牙槽窝内,同法观察。1个月时大部分为纤维性结合,根尖为骨性结合;3个月时为骨性结合,有较多骨组织长入种植体(多孔型)内;6个月时为骨性结合。生理性牙槽窝有利于种植体与周围组织的结合与稳固;多孔型比致密型固位快,可能与表面微孔有关;种植体与骨组织的结合是一种正合关系。     

Periodontal healing after replantation and autotransplantation of incisors in monkeys

The effect of injury to the cemental or alveolar part of the periodontal ligament upon periodontal healing after replantation and autotransplantation of teeth was studied in green Vervet monkeys. Sixty-six maxillary central incisors were replanted or autotransplanted after extra-alveolar periods of 18 min. saline storage or 120 min. dry storage. The animals were sacrificed after 8 weeks and the teeth examined histometrically. Identical healing was found in the following experimental groups: replantation or autotransplantation after 18 min. and replantation with or without removal of periodontal ligament in the alveolus. A significant increase in replacement resorption (ankylosis) compared to the 18 min. replantation group was found in the following groups: replantation and autotransplantation after 120 min., replantation after removal of periodontal ligament on the root surface and autotransplantation after 120 min. to a socket where the tooth was extracted 18 min. earlier. Autotransplantation after 18 min. to a socket where a tooth had been extracted 120 min. earlier led to a significant increase in the amount of replacement resorption compared to transplantation to an 18 min. socket. Based on these findings, it is concluded that the presence of an intact and viable periodontal ligament on the root surface is the most important factor in assuring healing without root resorption. The length of the extra-alveolar period also seems to exert some influence upon the socket, enhancing the development of ankylosis.     

Effect on periodontal healing of saline irrigation of the tooth socket before replantation

Abstract The following investigation was designed to study the healing of replanted teeth when the formation of a blood coagulum in the alveolar socket is avoided as much as possible before replantation. Eighteen maxillary incisors from 4 beagle dogs were used. The teeth were extracted and stored dry for 30 min in order to induce a standardized damage to the periodontal ligament cells, and were then replanted and splinted. Nine of the sockets were continuously irrigated with saline to achieve hemostasis before replantation. In 9 sockets a coagulum was allowed to form. After 2 wk the root canals were cleansed and filled with Ca(OH)₂ and the splints were removed. Three months later the dogs were sacrified and the premaxillas were removed and processed according to routine histologic methods. Transverse sections were cut and one section at every 500 μm interval was analyzed using light microscopy. Ankylosis was found in 3 teeth replanted in saline-irrigated sockets, while 8 teeth replanted in untreated sockets were ankylosed. Resorption without ankylosis was found in all teeth, irrespective of type of treatment of the alveolar sockets, but a tendency toward less extensive resorption areas was noted in the teeth replanted in saline-irrigated sockets. Thus, the present study indicates that continuous irrigation of the alveolar socket with saline before replantation promotes the normal healing of experimentally exarticulated teeth in dogs.     

Dynamics of dentoalveolar ankylosis and associated root resorption

Abstract The present experimental studies in monkeys were undertaken to study the initiation and progression of dentoalveolar ankylosis of replanted teeth and associated root resorption. Maxillary and mandibular lateral incisors were extracted and replanted after an extraoral period of 15 min or 1 h. Teeth with an extraoral period of 1 h were endodontically treated. Half the number of monkeys were given antibiotics at the time of replantation. The observation periods varied from 2 days to 40 weeks. Irrespective of the length of the extraoral period, initial root resorption and minor areas of ankylosis were found 1 week after replantation. The initial ankylosis was not preceded by root resorption. In teeth replanted after an extraoral period of 15 min the ankylotic area did not increase with increasing time after replantation. Instead the periodontal membrane was re-established, separating the root surface from the alveolar bone. In teeth replanted after an extraoral period of 1 h, the initial ankylotic area increased with increasing time after replantation. Eight weeks and more after replantation, most of the periodontal membrane was replaced by bone covered by osteoblasts and occasional osteoblasts that were in continuity with the endosteal cells outlining the marrow spaces of the alveolar bone. The cementum and dentin were then gradually resorbed with increasing time after replantation. Antibiotics given at the time of replantation reduced the initial inflammation in the periodontal membrane and the inflammatory root resorption after all observation periods and it also seemed to some extent to prevent bacteria from entering the necrotic pulp tissue. Based on the present results it is suggested that root resorption associated with dentoalveolar ankylosis is initiated by endosteal osteoblasts and is thus a hormonally regulated process. This is in contrast to inflammatory root resorption, which seems to be triggered by inflammatory cells.     

Dynamics of dentoalveolar ankylosis and associated root resorption

The present experimental studies in monkeys were undertaken to study the initiation and progression of dentoalveolar ankylosis of replanted teeth and associated root resorption. Maxillary and mandibular lateral incisors were extracted and replanted after an extraoral period of 15 min or 1 h. Teeth with an extraoral period of 1 h were endodontically treated. Half the number of monkeys were given antibiotics at the time of replantation. The observation periods varied from 2 days to 40 weeks. Irrespective of the length of the extraoral period, initial root resorption and minor areas of ankylosis were found 1 week after replantation. The initial ankylosis was not preceded by root resorption. In teeth replanted after an extraoral period of 15 min the ankylotic area did not increase with increasing time after replantation. Instead the periodontal membrane was re-established, separating the root surface from the alveolar bone. In teeth replanted after an extraoral period of 1 h, the initial ankylotic area increased with increasing time after replantation. Eight weeks and more after replantation, most of the periodontal membrane was replaced by bone covered by osteoblasts and occasional osteoblasts that were in continuity with the endosteal cells outlining the marrow spaces of the alveolar bone. The cementum and dentin were then gradually resorbed with increasing time after replantation. Antibiotics given at the time of replantation reduced the initial inflammation in the periodontal membrane and the inflammatory root resorption after all observation periods and it also seemed to some extent to prevent bacteria from entering the necrotic pulp tissue. Based on the present results it is suggested that root resorption associated with dentoalveolar ankylosis is initiated by endosteal osteoblasts and is thus a hormonally regulated process. This is in contrast to inflammatory root resorption, which seems to be triggered by inflammatory cells.     

A histological and micro-CT investigation in to the effect of NGF and EGF on the periodontal,alveolar bone,root and pulpal healing of replanted molars in a rat model - a pilot study

Background

This study aims to investigate, utilising micro-computed tomography (micro-CT) and histology, whether the topical application of nerve growth factor (NGF) and/or epidermal growth factor (EGF) can enhance periodontal, alveolar bone, root and pulpal tissue regeneration while minimising the risk of pulpal necrosis, root resorption and ankylosis of replanted molars in a rat model.

Methods

Twelve four-week-old male Sprague-Dawley rats were divided into four groups: sham, collagen, EGF and NGF. The maxillary right first molar was elevated and replanted with or without a collagen membrane impregnated with either the growth factors EGF or NGF, or a saline solution. Four weeks after replantation, the animals were sacrificed and the posterior maxilla was assessed using histological and micro-CT analysis. The maxillary left first molar served as the control for the corresponding right first molar.

Results

Micro-CT analysis revealed a tendency for all replanted molars to have reduced root length, root volume, alveolar bone height and inter-radicular alveolar bone volume. It appears that the use of the collagen membrane had a negative effect while no positive effect was noted with the incorporation of EGF or NGF. Histologically, the incorporation of the collagen membrane was found to negatively affect pulpal, root, periodontal and alveolar bone healing with pulpal inflammation and hard tissue formation, extensive root resorption and alveolar bone fragmentation. The incorporation of EGF and NGF did not improve root, periodontal or alveolar bone healing. However, EGF was found to improve pulp vascularisation while NGF-improved pulpal architecture and cell organisation, although not to the level of the control group.

Conclusions

Results indicate a possible benefit on pulpal vascularisation and pulpal cell organisation following the incorporation of EGF and NGF, respectively, into the alveolar socket of replanted molars in the rat model. No potential benefit of EGF and NGF was detected in periodontal or root healing, while the use of a collagen membrane carrier was found to have a negative effect on the healing response.     

牙周膜细胞松质骨基质支架复合移植促进牙周组织再生的研究

目的观察牙周膜细胞（PDLCs）接种松质骨基质（CBM）支架复合移植对牙周组织再生修复的影响和意义。方法将体外培养的狗自体PDLCs接种到CBM三维支架上,体外进行细胞计数和扫描电镜观察,并植人狗人工牙周组织缺损处,表面覆盖聚四氟乙烯膜（e-PTFE）,以单纯翻瓣组和只覆盖e-PTFE组作为对照。术后8周对动物组织标本进行组织学观察和测量,分析比较各组牙周组织的再生情况。结果PDLCs在CBM支架材料上形成良好的贴附并增殖,扫描电镜可见CBM具有良好的多孔网状结构,细胞在CBM上生长旺盛,伸展充分。自体PDLCs／CBM／e-PTFE膜复合植入组较单纯翻瓣组和e—PTFE组有更多的新生牙槽骨、新生牙周膜和新生牙骨质生成,且未见上皮长入。结论PDLCs接种松质骨基质支架复合移植能更有效地促进牙周组织再生和重建,CBM有望用作牙周组织工程的支架材料。     

阿仑膦酸钠联合四环素局部应用对延期再植干燥狗牙愈合的影响

目的:探讨阿仑膦酸钠(alendronate,ALN)联合四环素(tetracycline,TET)局部应用对延期再植干燥狗牙愈合的影响。方法:采用成年杂种狗3条,选择上颌双侧第1、2、5牙和下颌双侧第2、3、5牙为受试牙,共18对同名受试牙。随机将每对中的2颗同名受试牙分入实验组或对照组。所有受试牙均先接受根管处理。7d后拔牙,随即自然干燥60min;再植前实验组牙先被置于1mmol/L浓度的ALN溶液中浸泡5min,接着再被置于10ml/L TET溶液中浸泡5min;对照组牙仅被置于1mmol/L浓度的ALN溶液中浸泡5min。植后12周后取出含牙骨块,进行脱钙、制片、HE染色,对牙根的愈合情况进行组织形态学评价。结果:实验组牙骨质愈合的百分比均值高于对照组者,差异无显著性(P>0.05);实验组牙根炎症性吸收的百分比均值低于对照组者,差异有显著性(P<0.05)。结论:与单纯ALN局部应用比较,ALN联合TET局部应用不能增加延期再植干燥牙的牙骨质愈合,但能减少牙根炎症性吸收,有利于延长牙的使用寿命,具有一定的临床价值。     

成熟狗牙深低温保存延期再植的实验研究

目的 研究被长期冻存的成熟狗牙在再植后的牙根愈合情况。方法 成熟狗牙在根管充填后被拔除,采用Schwatz的下周膜冻存法,分别保存1周、3月、牙被再植8周后取出标本,用5％甲酸脱钙,横断切片,HE染色,参照Andreasen的方法进行组织学评价。结果 冻存1周组牙周膜愈合的百分比为64．53％,低于即刻再植组者（85％）,无显著性差异（P＞0．05）;冻存3月组者为50．3％,与即刻再植组者差异有显著性（P＜0．05）。结论 同人体角膜、牙肤、胰岛等组织一样,人体牙周膜也可以被长期冻存,并且再植后获得愈合;但新制备的牙槽窝一定程度上影响牙周膜愈合。     

Replantation with intentional rotation of a complete vertically fractured root using adhesive resin cement

Abstract  – This case describes intentional replantation with rotation of a complete vertically fractured root using adhesive resin cement. The fractured root was fixed with adhesive resin cement extra-orally. The tooth was replanted into the socket with rotation in order to avoid contact with the area where the periodontal ligament of the root surface was lost and the area where the alveola bone was lost along the fracture line. At follow-up 18 months later, the tooth was asymptomatic and radiographically showed an increase in the density of the alveolar bone, and the periodontal pockets were improved.     

完全脱位牙即刻与延迟再植根吸收的动态观察

目的：动态观察实验大鼠再植牙牙根吸收及愈合过程,辅助临床治疗及预防再植牙牙根吸收。方法：30只6周龄SPF级Wistar雄性大鼠,分为6组,每组5只,其中一组为空白对照组。实验组大鼠双侧上颌第一磨牙脱位后再植,每只大鼠随机选取一侧脱位牙齿即刻再植,对侧同名牙则于体外干燥保存30min后再植回牙槽窝。分别于术后1、3、7、14、21d处死,分离上颌骨,拍摄x线片,应用IPP软件测量上颌第一磨牙近中根根周透影面积。标本脱钙后制作切片、HE染色,进行组织学观察。结果：再植牙根尖周透影面积随时间延长而增大,干燥组表现尤其明显;组织学上表现为初期炎症反应较明显,随着炎症发展,牙根表面吸收陷窝逐渐增多、增大,后期即刻组牙髓及牙周膜修复反应明显,干燥组牙槽骨修复反应强烈,牙根、牙周膜逐渐被类骨质样组织替代。结论：再植牙初期以炎症反应为主,后期主要表现为修复反应,即刻与延迟再植导致牙周膜细胞活性不同决定了再植牙根吸收的进展。