外伤全脱位年轻恒牙再植的临床研究

目的：观察不同离体时间的年轻恒牙再植后的成功率。方法：详细记录60颗全脱位牙离体时间、手术及牙愈合情况,对患者进行1～2年的随访。结果：60颗脱位牙（离体时间为15min～16h）再植后牙周膜愈合26颗（43．3％）,其中牙髓成活19颗（31．67％）;骨性愈合31颗（51．67％）;纤维愈合3颗。术后对38颗牙进行了根管治疗。结论：缩短脱位牙的离体时间、尽可能保存牙周膜的活性等是再植成功的重要因素。     

外伤全脱位牙自体再植术的临床观察研究

目的：分析６０个外伤全脱位前牙即期再植的随访结果总结经验。方法：详细记录牙离体时间、手术及术后处理情况,定期对患者进行随访。结果：６０个脱位牙再植后临床疗效优３７个（６１．７％）、良１８个（３０．０％）、差５个牙（８．３％）,３个牙１年内拔除。３年成功率８３．０％、５年成功率６１．７％。判断为牙周膜愈合２０个、骨性愈合３５个、纤维愈合５个牙。牙髓活力测定,活力阳性２３个、阴性３７个。术后对２０个牙施行了根管治疗。结论：细心保护脱位牙根面牙周膜、良好固定、预防感染、防止咬合创伤是再植成功的重要因素。术后定期复查,发现问题及时处理,有利于提高再植牙远期成功率。     

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。     

釉质基质蛋白诱导延迟再植牙牙周愈合的研究

目的：研究应用釉基质蛋白对延迟再植比格犬恒切牙牙周再生的影响。方法：选取3只比格犬的15颗干燥60min的切牙随机分为两组,实验组10颗牙根涂釉基质蛋白;对照组5颗牙根不涂釉基质蛋白,进行再植。8周后处死犬,每隔500μm切取5μm厚的横断切片作组织学观察。结果：与对照组相比,实验组牙再植后能显著地增加牙周膜性愈合的数量（P〈0．001）,并减少替代性吸收（P〈0．001）。结论：釉基质蛋白能对延迟再植牙的牙周愈合有促进作用。     

73个再植牙的临床观察

目的：通过对73个再植牙的临床观察，总结再植牙成功的经验。方法：对73个再植牙观察0．5－10年，对临床资料进行总结分析。结果：再植成功90．41％。达到牙周膜愈合38．36％，骨性愈合57．53％。牙髓重建8个。脱落时间＞5d亦再植成功。结论：掌握好适应证，正确操作，能提高再植牙成功率。     

实验性即刻再植牙大鼠模型的建立

目的:建立大鼠即刻再植牙动物模型,观察再植牙的愈合过程与牙根外吸收的表现。方法:30只6周龄SPF级Wist-ar雄性大鼠,分为6组,每组5只。单侧上颌第一磨牙脱位后即刻再植,对侧同名牙为自身对照。分别于术后1、3、7、14、21、28d处死,分离上颌骨;拍根尖X线片,应用图像分析系统测量近中根根尖周阴影面积;标本切片、HE染色,进行组织学观察。结果:近中根根尖周阴影面积随时间延长而增大,近中根牙根表面吸收陷窝增多,牙周膜局部宽度变窄,新生骨样组织增加。结论:本法成功建立再植牙动物模型,该模型稳定可靠,能完整反映再植牙愈合方式,为进一步研究再植牙愈合机理提供了很好的研究模型。     

牙根发育程度对不同类型恒牙外伤性部分脱位预后的影响

目的:探讨牙根发育程度对不同类型恒牙外伤性部分脱位预后的影响,为临床预测其预后提供参考。方法:对202例恒牙外伤性部分脱位进行回顾性研究,重点统计分析(卡方检验) 3种不同类型牙部分脱位(牙移位、半脱位和嵌入深部)不成熟组(A组)、儿童青少年成熟组(B组)、成人成熟组(C组)各组牙周膜的愈合状况的差异。结果:牙移位类型A、B、C3组内及两两之间牙周膜的愈合状况均无显著性差异(P>0. 05),而半脱位和嵌入深部两种类型A、B、C3组内牙周膜的愈合状况有显著性差异(P<0. 05),其中半脱位类型A与B组、B与C组之间无显著性差异,而A与C组之间有显著性差异;嵌入深部类型A与B组之间无显著性差异,而A与C组、B与C组之间有显著性差异。结论:牙根的发育成熟程度对牙移位类型的牙周膜性愈合的影响不大,而对半脱位,尤其是嵌入深部类型的牙周膜性愈合有一定的影响。     

微创拔牙技术在纵折后牙粘结再植术中的临床应用

目的：从临床疗效、牙周愈合情况两方面探索微创拔牙技术对拔牙再植法治疗纵折后牙成功率影响。方法：来我院诊治的符合适应症的纵折后牙共50例进行拔牙再植法的治疗,局麻下拔除折裂牙,其中25例常规拔牙作为对照组,25例使用微创拔牙,然后在体外粘结,再植入牙槽窝,术后2周临时冠修复。定期复查,根据临床表现、牙周状况分级,统计分析。结果：拔牙过程中,对照组断根2例,而微创组无断根,2年随访成功率分别为对照组56%和微创组84%,对照组牙周膜愈合（4%）明显少于骨粘连愈合（72%）,而微创组牙周膜愈合达44%,与骨粘连愈合（52%）接近。结论：拔牙再植法是一种保存纵折后牙的有效方法,微创拔牙技术有利于再植后的牙周愈合及预后。     

深低温冻存对牙周膜干细胞膜片增殖和分化能力的影响

目的：研究深低温冻存对牙周膜干细胞膜片增殖和分化能力的影响。方法：将牙周膜干细胞膜片用90％胎牛血清＋10％ DMSO 冻存液冻存3月后复苏,采用甲基噻唑基四唑（MTT）法、von Kossa 染色和油红 O 染色法检测冻存对增殖和分化的影响。结果：冻存牙周膜干细胞膜片与新鲜牙周膜干细胞膜片的增殖率和成骨、成脂分化能力没有明显差异。结论：牙周膜干细胞膜片经深低温保存后可继续保持冻存前原有的增殖能力和多向分化能力。     

氯霉素对人牙周膜细胞增殖及超微结构的影响

目的：比较0．25％氯霉素和生理盐水对人牙周膜细胞增殖和超微结构的影响,以提高脱位牙再植的疗效。方法：采用组织块法体外培养人牙周膜细胞,取第5代培养细胞,分别加入氯霉素、生理盐水和DMEM培养液作用1h,在作用后0、12、24、48h进行细胞计数．观察对牙周膜细胞增殖的影响。采用透射电镜观察人牙周膜细胞超微结构的变化。数据采用SAS9．1软件包进行方差分析。结果：在0、12、48h时间点．氧霉素组和生理盐水组的细胞数显著低于DMEM培养液对照组（P〈0．0001）;在24h时间点,生理盐水组的细胞数显著低于对照组（P〈0．05）。各时间点氯霉素和生理盐水两组细胞计数无显著差异（P〉0．05）。电镜观察,氯霉素可导致人牙周膜细胞线粒体空泡化．内质网减少。结论：氯霉素对人牙周膜细胞增殖的影响与生理盐水没有区别,但对人牙周膜细胞的超微结构有损伤作用。     

Experimental study on the effect of replantation of immature permanent teeth on the periapical and periodontal tissues

Replantation and semi-rigid fixation were performed on canine immature permanent teeth, and one week after replantation the teeth were treated by root filling with calcium hydroxide. The root apex and periodontium of the teeth with replantation were examined for changes regularly during the experiment by microradiographic, fluorescence microscopic, polarizing microscopic and X-ray observation of undecalcified horizontal continual ground sections. The results obtained were as follows: 1) Immediately after replantation, root formation was observed, but its formation was found to cease at a relatively early time. No site of the root showed any inflammatory resorption. 2) The dentine of the teeth with replantation was narrow, and the whole tooth substance showed discoloration due to penetration of calcium hydroxide. 3) the periodontal space surrounding the teeth with replantation was decreased daily by new bone actively formed from the alveolar bone proper and by a thin cementum layer added on the periodontal surface. This change occurred from one week after replantation. 4) The width of the periodontal space of the teeth with replantation, which had been wider than that of a control tooth, was increased and decreased daily at the cervix and root apex and the central part of the root, respectively. 5) Collagen fibers of the periodontal membrane were present in the periodontal space of the teeth with replantation, together with regeneration of the periodontal membrane that had been cut by extraction. 6) There were no changes due to replantation in the two teeth adjacent to the tooth with replantation or the lateral jaw.     

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。     

The effect of saline storage before replantation upon dry damage of the periodontal ligament

Abstract The effect of 30 min of saline storage before replantation of teeth, which had been dried out for 30 min, was studied in 10 Green Vervet monkeys (Cercopithecus aethiops). Maxillary central incisors were extracted and dried out for 30 min, after which 1 incisor was replanted and the other transferred to a saline solution for 30 min before replantation. No splinting or endodontic treatment was carried out. The teeth were examined after 8 wk. Histometric analysis showed identical extent of root resorption in the 2 groups, with ankylosis being the dominant resorption type, and with very limited pulpal repair in either group. It is concluded that saline storage under the experimental conditions chosen had no effect on development of root resorption or pulpal repair, presumably because 30 min dry storage had inflicted close to maximal damage on the periodontal ligament at the root surface. On the other hand, it is of clinical importance that a certain delay in the replantation procedure does not influence periodontal and pulpal healing, as long as the tooth is kept in saline storage. This suggests that replantation under these conditions can be reserved for dental professionals, rather than favoring immediate replantation by anyone ‘on-the-spot’.     

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.     

Transport and storage of human teeth in vitro for autotransplantation and replantation.

A method has been devised for transporting and storing human teeth in vitro for autotransplantation and replantation. In the transplantation and replantation of accidentally lost teeth, the viability of the cells covering the root is of vital importance. Injury of the jaw and contamination of the tooth often prevent immediate replantation. To enable transportation and storage of teeth while maintaining viability of the periodontal ligament during the healing period after trauma, the following technique was worked out. With use of a transport medium and a tissue-culture technique, 35 human teeth were transported long distances (20 hours) to a tissue-culture laboratory and preserved for different periods of time. Three teeth were lost because of contamination. Twenty-one of the teeth were cultivated in tissue-culture medium at 37 C for four weeks; 11 of the teeth were stored in liquid nitrogen at -196 C for 27 weeks. After transportation and storage, it was possible to maintain the viability of the cells of the periodontal membrane of the teeth. Two cases are described wherein immediate transplantation and replantation were impossible. After transport to the laboratory, the teeth were stored for five weeks in one case and for three months in another case before replantation.     

Influence of enamel matrix derivative (Emdogain®) and sodium fluoride on the healing process in delayed tooth replantation: histologic and histometric analysis in rats

Abstract – Although it has already been shown that enamel matrix derivative (Emdogain^®) promotes periodontal regeneration in the treatment of intrabony periodontal defects, there is little information concerning its regenerative capacity in cases of delayed tooth replantation. To evaluate the alterations in the periodontal healing of replanted teeth after use of Emdogain^®, the central incisors of 24 Wistar rats (Rattus norvegicus albinus) were extracted and left on the bench for 6 h. Thereafter, the dental papilla and the enamel organ of each tooth were sectioned for pulp removal by a retrograde way and the canal was irrigated with 1% sodium hypochlorite. The teeth were assigned to two groups:in group I, root surface was treated with 1% sodium hypochlorite for 10 min (changing the solution every 5 min), rinsed with saline for 10 min and immersed in 2% acidulated‐phosphate sodium fluoride for 10 min; in group II, root surfaces were treated in the same way as described above, except for the application of Emdogain^® instead of sodium fluoride. The teeth were filled with calcium hydroxide (in group II right before Emdogain^® was applied) and replanted. All animals received antibiotic therapy. The rats were killed by anesthetic overdose 10 and 60 days after replantation. The pieces containing the replanted teeth were removed, fixated, decalcified and paraffin‐embedded. Semi‐serial 6‐μm‐thick sections were obtained and stained with hematoxylin and eosin for histologic and histometric analyses. The use of 2% acidulated‐phosphate sodium fluoride provided more areas of replacement resorption. The use of Emdogain^® resulted in more areas of ankylosis and was therefore not able to avoid dentoalveolar ankylosis. It may be concluded that neither 2% acidulated‐phosphate sodium fluoride nor Emdogain^® were able to prevent root resorption in delayed tooth replantation in rats.     

Apexification of a replanted tooth using mineral trioxide aggregate

Abstract –  The most important factors determining periodontal healing after replantation of an avulsed tooth are the extra oral period and the media in which the tooth is preserved before replantation. This case report describes an adequate periodontal healing of an avulsed immature tooth replanted after 20 min of extra alveolar dry time. Vitality was not regained and after disinfection of the pulp space mineral trioxide aggregate was used as the root filling. Follow-up confirmed complete healing periradicularly.     

Immediate tooth replantation in rats: effect of systemic antibiotic therapy with amoxicillin and tetracycline

Objectives

The aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in immediate rat tooth replantation.

Materials and methods

Ninety rats had their incisors extracted and stored in saline for 5 min. Next, the teeth were replanted, and the animals were assigned to three groups according to the antibiotic administered by oral gavage: control group, amoxycillin group, and tetracycline group. Euthanasia was performed at 7, 15, and 30 days after replantation.

Results

Regardless of the evaluation period, the connective tissue underlying the epithelial attachment and the periodontal ligament showed statistically significant difference relative to the acute inflammatory infiltrate, which was more intense in the control group followed by the tetracycline group.

Conclusion

These results point to the fact that systemic antibiotic therapy (SAT) in immediate tooth replantation is beneficial to pulpal and periodontal ligament repair and that amoxycillin is an excellent option.

Clinical relevance

There is a lack of randomized studies assessing how the use of systemic antibiotics could influence tooth healing after immediate replantation.

     

Interventions for treating traumatized permanent front teeth: avulsed (knocked out) and replanted

Background: Dental trauma is common. One of the most severe injuries is when a permanent tooth is knocked completely out (avulsed) of the mouth. In most circumstances the tooth should be replanted as quickly as possible. There is uncertainty on how best to prepare teeth for replantation. Objectives: To compare the effects of a range of interventions for managing traumatized permanent teeth with avulsion injuries. Search strategy: The Cochrane Oral Health Group’s Trials Register (to 28th October 2009); CENTRAL (The Cochrane Library 2009, Issue 4); MEDLINE (1950 to October 2009); EMBASE (1980 to October 2009); http://www.clinicaltrials.gov/;www.controlled‐trials.com/ and reference lists of articles were searched. There were no language restrictions. Selection criteria: Only randomized controlled trials (RCTs), that included a minimum follow‐up period of 12 months, for interventions for avulsed and replanted permanent teeth were considered. Data collection and analysis: Two review authors independently extracted data and assessed trial quality and the risk of bias in studies to be included. Main results: Three studies, involving a total of 162 patients and 231 teeth were identified. Study one (with a high risk of bias) investigated the effect of extra‐oral endodontics. This showed no significant difference in radiographic resorption compared with intra‐oral endodontics provided at week 1 for teeth avulsed for longer than 60 minutes dry time. Study two (which had a moderate risk of bias) investigated a 10‐minute soaking in thymosin alpha 1 prior to replantation and then its further use as a daily gingival injection for the first 7 days. They reported a strong benefit at 48 months (14% with periodontal healing in the control group versus 77% for the experimental group). Study three (with a high risk of bias) investigated a 20‐minute soaking with gentamycin sulphate (4 × 107 U/L) for both groups prior to replantation and then the use of hyperbaric oxygen daily in the experimental group for 80 minutes for the first 10 days. They reported a strong benefit at 12 months (43% periodontal healing versus 88% for the experimental group). There was no formal reporting of adverse events. Authors’ conclusions: The available evidence suggests that extra‐oral endodontics is not detrimental for teeth replanted after more than 60 minutes dry time. Studies with moderate/high risk of bias indicate that soaking in thymosin alpha 1 and gentamycin sulphate followed by hyperbaric oxygen may be advantageous. However, they have not previously been reported as interventions for avulsed teeth and need further validation. More evidence with low risk of bias is required and, with the low incidence of avulsed teeth, collaborative multicentre trials are indicated. Plain language summary: Treatments for managing knocked out and replanted front teeth. Injuring your front teeth during childhood is common. One of the most severe injuries occurs when the tooth is knocked totally out of the mouth (avulsed). Often the best option is to replant the tooth as quickly as possible. This is true only for permanent teeth. Once replanted the tooth can heal in two ways if managed correctly. Ideally the ligament around the root reforms and the tooth can be expected to last as long as any other tooth; this is known as ‘periodontal healing’. When there is too much damage to the ligament, healing occurs by bony replacement and the tooth is replaced by bone and lost over a few years. This is called ‘bony healing’. Bony healing causes significant problems in the medium term for children and treatments for this are the subject of a different Cochrane review. A missing front upper tooth or teeth, as a result of not replanting an avulsed tooth or as a treatment for bony healing, can have a major effect on dental and facial ‘good looks’. This can affect the individual’s self‐esteem and general social interaction, as well as how others think and see them. This Cochrane review investigated what treatments encourage the tooth to repair by periodontal healing. Three studies were found. The benefits of these treatments require further investigation before specific medicaments can be advised. This is because the studies had weakness in their design which may have influenced the benefits they found. The following general treatment principle can be concluded which reinforces current treatment guidelines: For teeth with little chance of periodontal healing, a root canal treatment can be carried out before the tooth is replanted without further detrimental effects.     

The effect of Emdogain gel on periodontal healing in replanted monkeys' teeth

OBJECTIVE: We sought to histologically evaluate the effect of Emdogain gel on periodontal healing in monkeys' teeth undergoing delayed replantation.Study design Mature monkey teeth simulating avulsion were endodontically treated before extraction. Negative control teeth (group N = 10 roots) underwent immediate replantation, whereas the rest were bench-dried for 1 hour and treated in one of the following ways before replantation: the positive control teeth (group P = 12 roots) had no further treatment; group C teeth (4 roots) had the periodontal ligament removed; group D teeth (10 roots) were treated with Emdogain gel; group E teeth (6 roots) had the periodontal ligament removed before the application of Emdogain gel; and group F teeth (7 roots) had the periodontal ligament removed, the root surface conditioned, and Emdogain gel applied. Periodontal healing was evaluated after 16 weeks by undertaking histomorphometric analysis. RESULTS: The Kruskal-Wallis and Mann-Whitney U tests revealed that group N teeth had a statistically higher occurrence of complete healing than did all other groups, whereas group P was not significantly different in any of the healing categories from D, E, and F, the groups in which Emdogain gel was used. Group C teeth had a significantly higher occurrence of replacement root resorption than did the teeth in groups P and F-but were not significantly different from teeth in groups D and E. CONCLUSION: Emdogain gel did not appear to significantly reduce replacement resorption in monkeys' teeth that had undergone delayed replantation.