儿童50 颗恒牙再植后的回顾性研究

目的:分析再植牙的预后及影响预后的相关因素,观察再植后牙根吸收出现时间及影响因素.方法:对2000～2006 年于北京大学口腔医学院儿童口腔科注册的系统病历中,观察期≥6 个月的全脱位牙再植病历进行回顾性研究,记录患者及再植牙信息.应用卡方检验和生存分析(cox regression)进行统计学分析.结果:符合纳入标准的外伤病历39 份,涉及再植牙50 颗.牙周膜愈合的发生率为18%,牙根吸收发生率为82%,替代性吸收是最常见的牙周组织预后形式(64%).牙根发育情况和保存方式与牙周组织预后具有显著相关性;牙根发育情况、牙髓治疗时机可以影响牙根吸收出现的时间(P<0.05).结论:替代性吸收是再植牙最常见的牙周组织预后形式.再植牙牙根发育情况和保存方式与牙周组织预后具有显著相关性.牙根发育情况、牙髓治疗时机可以影响牙根吸收出现的时间.     

年轻恒牙震荡和移位后牙髓与牙根变化的临床研究

年轻恒牙外伤后,牙髓坏死和牙根吸收在牙齿震荡和牙齿移位中的发生率及发生的时间;牙根的表浅性吸收,置换性吸收,炎症性吸与外伤类型的关系。方法从１９８４－１９９６年在北京医科大学附属口腔医院儿科就诊的２０１例前牙外伤发生牙震荡和牙移位患者的病历资料中选择７９例１５７颗无冠折根折的外伤牙,并且如果有牙松动者使用全牙Ｈｅ     

牙齿再植的临床治疗探讨

牙齿再植的临床治疗探讨张旭光由于外伤等原因导致的牙齿脱落病例逐年增多，但大多数脱落的牙齿可以借助再植的方法得以保留，而且牙齿再植在口腔医学其它领域也可应用。近二、三十年来，以Ａｎｄｒ－ｅａｓｅｎ等学者对再植牙牙根吸收的病因和病理过程，牙髓和牙周膜创伤...     

促进撕脱性损伤牙延期再植后牙周愈合的研究进展#br#

牙撕脱性损伤是牙外伤中预后较差的一种,目前对于恒牙撕脱性损伤的治疗一般采用牙再植术,再植时根面牙周组织活性对其预后至关重要。临床调查显示,撕脱性损伤牙再植多为延期再植,离体牙根面牙周膜在干燥状态下脱水坏死是导致术后病理性牙根吸收的主要原因。国际牙外伤协会建议在延期再植时采取适当措施,促进再植牙的牙周愈合再生,减少病理性吸收,延长再植牙使用寿命。文章结合2020版国际牙外伤协会撕脱性损伤牙治疗指南对现有促进撕脱性损伤牙延期再植后牙周愈合相关研究做一综述,包括根面处理、药物及干细胞治疗在牙再植术中的应用。     

再植牙牙根替代性吸收的发生与防治

近年来由于交通事故不断上升 ,使外伤脱位牙的发生率逐渐上升。据报道 ,在所有外伤中 ,造成恒牙脱位的占 0 .5 %～ 1 6 % [1] 。牙外伤脱位最常用的治疗方法是牙再植术。在临床上 ,牙根替代性吸收是再植牙常见的一个并发症。本文进一步阐明牙根替代性吸收发生的机制以及相应的防治措施综述如下。1　牙根替代性吸收的发生机制　　造成牙再植失败的原因很多 ,其中炎症性吸收和替代性吸收是造成牙再植失败的主要原因。根骨粘连也叫替代性吸收。根骨粘连的过程是在牙糟壁上形成的骨小梁 ,逐渐生长 ,越过牙周膜间隙 ,与牙根表面融合。然后这些骨…     

氢氧化钙在脱位再植牙牙髓坏死治疗中的应用

目的：观察氢氧化钙（calcium hydroxide,CH)及其制剂作为根管内封药和根管充填糊剂在外伤脱位牙牙髓坏死根管治疗术（root canal therapy,RCT)中的应用效果。方法：对使用不同药物根管内封药和不同根管糊剂充填根管治疗外伤脱位再植牙牙髓坏死的疗效进行对比。结果：CMCP、FC、IPI、CH组根管治疗期间的急症发生率差异非常明显，疼痛指数亦以CH组最低；1年后牙根吸收情况和2年失牙率、牙再植成功率CH组与其它组有非常显著差异。结论：CH可以预防其急症的发生和减少牙根吸收，提高牙再植的成功率。     

牙齿保存液的研究进展

牙脱位在儿童和青少年中的发生率呈逐渐上升趋势,牙齿离体后应尽快保存于合适储存介质中以备再植。理想的保存液应能保持牙周膜细胞的形态与活性,减少牙再植后牙根发生置换性吸收,提高牙再植成功率。笔者对牙齿保存液的研究进展作一综述。     

阿仑膦酸钠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)溶液浸泡对延期再植干燥狗牙愈合的影响。方法选用成年杂种狗2条,以上颌双侧第1、2、5牙和下颌双侧第2、3、5牙为受试牙,右侧受试牙归入实验组,左侧受试牙归入对照组。所有受试牙均先做根管处理。7d后拔牙,自然干燥60min;实验组牙再植前被置于1mmol/L的阿仑膦酸钠溶液中浸泡5min;对照组牙再植前不被作其他任何处理。再植12周后取出含牙骨块。经脱钙、切片、HE染色后,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明显高于对照组者(P<0.01);实验组牙根炎症性吸收与替代性吸收的百分比均值分别低于对照组者(P<0.05)。结论ALN能有效地改善延期再植干燥牙的愈合,增加牙骨质愈合,减少牙根炎症性吸收与替代性吸收。     

根管治疗牙正畸加力后根吸收的相关因素研究

目的研究固定正畸治疗对根管治疗牙牙根吸收的影响和相关因素分析。方法选择正畸治疗前口腔内已完善根管治疗牙45例,利用治疗前后的全口曲面断层片,以改良根吸收分级法评估患者治疗前后牙根形态变化,分析正畸治疗对根管治疗后牙根吸收的影响。结果①正畸治疗后根管治疗牙牙根吸收有所增加,差异具有统计学意义（P〈0．001）;②性别是影响正畸治疗后根管治疗牙牙根吸收方程最为显著的因素（P〈0．05）,提示女性发生根吸收的风险大于男性;③正畸治疗后根管治疗牙与对侧活髓牙比较牙根吸收程度的改变差异没有统计学意义（P〉0．05）;④在所观察的样本中,无论根管治疗牙齿与活髓牙均未见3级根吸收。结论根管治疗牙在固定正畸治疗后可能发生一定程度的根吸收改变,但并不比活髓牙的风险更高。     

牙根吸收的诊断与治疗

临床上对于牙根内、外吸收常常难以作出准确的诊断和治疗。观察X线片时，这些缺陷容易被混淆。牙髓的状态以及在牙根吸收过程中的作用也容易被错误认识，尤其在缺乏能够提供诊断性意见的检查方法的情况下。目前尚不清楚牙根吸收发生的真正原因．但对牙根吸收的判断会影响治疗计划的制定。治疗计划可能包括外科修复、根管治疗甚至拔除．这取决于吸收的程度及范围。本文旨在介绍牙根内、外吸收的特点，并介绍如何通过现有的治疗手段保存患牙。     

A prospective study of factors affecting survival of replanted permanent incisors in children

Objective . To examine the factors associated with the onset of resorption in replanted avulsed permanent incisor teeth and to demonstrate their patterns of survival free of resorption.
Setting . Department of Paediatric Dentistry, Belfast.
Design . Prospective recording of the timing of the injury and of replantation, the storage media, the degree of root development and contamination, and the completion of root treatment. Clinical and radiographic reviews at 3-month intervals. Root resorption classified as replacement and inflammatory. Logistic regression and survival curves with freedom from resorption as outcomes.
Results . In 50 avulsed incisors in children aged 6–16 years the best predictor of overall resorption was total time of dryness, and that for replacement resorption was total extra-oral time. The timing of detection of resorption varied from 102 days to 997 days.
Conclusion . Both total extra-oral time and time stored dry are important factors for the onset of resorption in replanted avulsed teeth in children.     

Periodontal and pulpal healing of monkey incisors preserved in tissue culture before replantation.

The effect of delayed replantation and tissue culture as a prevention against root resorption was examined in green Vervet monkeys (Cercopithecus aethiops). Extracted incisors were kept in tissue culture medium (Eagle's medium) for 5--14 days before replantation. The extra-alveolar dry period before tissue culture ranged from to 0 to 60 min. Incisors not subjected to tissue culture served as controls. The animals were sacrificed 8 weeks after replantation. The following histologic parameters were registered for each tooth: surface resorption, inflammatory resorption, replacement resorption (ankylosis), downgrowth of pocket epithelium, and periapical inflammatory changes. The evaluation of the pulp included the extent, recorded in mm, of pulp survival. Histometric evaluation showed that teeth immediately placed in tissue culture medium for 5--14 days showed improved periodontal healing, exhibiting significantly less inflammatory resorption than control teeth immediately replanted. Also the extent of pulp survival was significantly increased in teeth replanted after tissue culture. Teeth bench-dried for 60 min and thereafter placed in tissue culture medium also showed a significant reduction in the amount of inflammatory resorption and increased amount of pulp survival compared with control teeth replanted after the 60-min dry extra-alveolar period. Replacement resorption (ankylosis) was found in all teeth in both groups.     

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.     

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.     

Timing of calcium hydroxide therapy in the treatment of root resorption in replanted teeth in dogs

Abstract The effect of time of the onset of calcium hydroxide (CH) pulpectomy on root resorption of 31 permanent dog incisors was investigated. CH pulpectomy was delayed 4, 9, 14 and 18 days after the teeth were extracted and replanted. Control teeth were replanted 1) without pulpectomy, 2) with a pulpectomy only or 31. with a pulpectomy and CH filling. All teeth were prepared for histologic evaluation 8 weeks after the teeth were replanted. Cross section were examined using a computer microscope and linear (jam) and/or square areas (μm²) of surface (SRR), inflammatory (IRR), and replacement (RRR) root resorption were calculated. From this data the percentage of linear and area resorption was averaged for each group. Duncan multiple range t-test (P<0.05) revealed that teeth in which a pulpectomy with CH filling was done extraorally had significantly greater SRR than the rest of the groups; teeth in which a pulpectomy without CH filling was done extra orally had significantly greater RRR than teeth in which CH pulpectomy was delayed for 18 days; there was no significant difference in SRR. IRR or RRR when CH placement was delayed 4, 9, 14 or 18 days after replantation. Although it was not significant the overall resorption was least when CH pulpectomy was delayed 18 days.     

Periodontal healing of replanted dog teeth stored in Viaspan, milk and Hank's balanced salt solution

Abstract This study examined, histologically, periodontal healing and root resorption of replanted dogs teeth stored in Viaspan for different time periods and compared these healing patterns to those after storage in milk or Hank's balanced salt solution (HBSS). Seventy-two beagle incisors were endodontically treated, extracted, randomly divided and placed in Viaspan or milk for 6, 12, 24 and 36 h, and Viaspan or HBSS for 36, 48, 72 and 96 h, after which they were replanted. Four negative control teeth were immediately replanted while four positive controls were allowed to dry for one hour before replantation. All replanted teeth were splinted for 14 days. Two months after replantation the clogs were killed and the teeth histologically examined for healing of the supporting tissues. For Viaspan neither replacement nor inflammatory root resorption was seen after 6 and 12 h storage. A statistically significant rise in the incidence of replacement resorption was seen at 24, 36 and 48 h which decreased again at 72 and 96 h to levels equal to storage for 6 and 12 h. The occurrence of inflammatory root resorption was low and significantly increased only at 48 h after which it decreased significantly again. Viaspan proved superior to milk as a storage medium. Teeth stored in HBSS showed healing results similar to those stored in Viaspan.     

Periodontal healing of replanted dog teeth stored in Viaspan, milk and Hank's balanced salt solution.

This study examined, histologically, periodontal healing and root resorption of replanted dogs teeth stored in Viaspan for different time periods and compared these healing patterns to those after storage in milk or Hank's balanced salt solution (HBSS). Seventy-two beagle incisors were endodontically treated, extracted, randomly divided and placed in Viaspan or milk for 6, 12, 24 and 36 h, and Viaspan or HBSS for 36, 48, 72 and 96 h, after which they were replanted. Four negative control teeth were immediately replanted while four positive controls were allowed to dry for one hour before replantation. All replanted teeth were splinted for 14 days. Two months after replantation the dogs were killed and the teeth histologically examined for healing of the supporting tissues. For Viaspan neither replacement nor inflammatory root resorption was seen after 6 and 12 h storage. A statistically significant rise in the incidence of replacement resorption was seen at 24, 36 and 48 h which decreased again at 72 and 96 h to levels equal to storage for 6 and 12 h. The occurrence of inflammatory root resorption was low and significantly increased only at 48 h after which it decreased significantly again. Viaspan proved superior to milk as a storage medium. Teeth stored in HBSS showed healing results similar to those stored in Viaspan.     

Long‐term retention of avulsed maxillary permanent incisors replanted after prolonged non‐physiological storage

Ankylosis and external replacement resorption (ERR) are two typical biological responses to delayed replantation of avulsed teeth in cases where adequate root canal treatment is performed. The patient's growth stage affects the progression of root resorption and the long‐term outcome of the affected teeth. This case report describes the long‐term outcome of an 18.5‐year‐old patient following an accident in which both of his maxillary central incisors were avulsed and replanted after four hours of non‐physiological storage. ERR and ankylosis of teeth 11 and 21 were detected clinically and radiographically during the second year of follow‐up. Sixteen years after replantation, replacement resorption was progressing very slowly, enabling functional tooth retention with favorable esthetics. Young adults, with delayed replantation of avulsed teeth, may benefit from tooth retention with slow ERR.     

Replantation of teeth and antibiotic treatment

Abstract Administration of antibiotics is usually recommended when a traumatically avulsed tooth is replanted, in order to prevent bacterial contamination. In the present study, permanent lateral incisors of monkeys were extracted, allowed to dry for 1 h and then replanted. Some teeth had their pulp chambers opened labially and left open for 3 wk after replantation. The monkeys were treated with antibiotics (i.m.) either at the lime of replantation or 3 wk after replantation. In some monkeys, antibiotics were placed in the pulpal cavity. Comparisons were made of the effect of endodontic treatment on periodontal healing and root resorption. The monkeys were killed 8 wk after replantation. It was found that after systemic antibiotic treatment at the time of replantation there was no inflammatory root resorption. Also, endodontic treatment at the time of replantation prevented inflammatory root resorption. When systemic antibiotic treatment was instituted 3 wk after (he replantation, there was no reduction of the inflammatory root resorption as compared with teeth without antibiotic treatment. Application of antibiotics in the pulp 3 wk after replantation almost completely eliminated the inflammatory resorption. In all the treatment groups where administration of antibiotics or endodontic treatment had prevented, reduced or eliminated inflammatory root resorption, 30–45% of the root surface area was ankylotic 8 wk after replantation.     

Effect of stannous fluoride and tetracycline on repair after delayed replantation of root-planed teeth in dogs

Mandibular incisors were extracted and allowed to dry in air for 45 min. They were then root-planed extensively, leaving a cervical collar and the apical region uninstrumented, to prevent direct contact between root surface and alveolar bone after replantation while, at the same time, enabling precise and stable reseating of the tooth. Control teeth were replanted either without further treatment or after treatment with citric acid for 3 min. Experimental teeth were treated before replantation with 1% SnF2 for 5 min, 1% tetracycline HCl for 5 min, or 1% SnF2 followed by 1% tetracycline. Histometric analysis of healing in the root-planed areas showed minimal amounts of inflammatory resorption and ankylosis after 21 days in experimental teeth as compared with the control teeth. A persisting inflammatory reaction in the periodontal ligament without root resorption was, however, frequently seen. The observations confirm that the frequency of adverse healing reactions after delayed replantation of teeth from which nonvital soft tissue remnants have been removed can be reduced by demineralizing the root surface and preventing mechanical trauma to the root surface in the postoperative period. Root surface treatment with SnF2 followed by tetracycline resulted in complete absence of inflammatory resorption and ankylosis in this short-term experiment.