Effect of root surface treatment with propolis and fluoride in delayed tooth replantation in rats

Abstract – Replantation is an acceptable option for treatment of an avulsed permanent tooth. Nevertheless, an extended extraoral period damages the periodontal ligament and results in external root resorption. The purpose of this study was to assess by histologic and histometric analysis, the influence of propolis 15% (natural resinous substance collected by Apis mellifera bees from various plants) and the fluoride solution used as root surface treatment on the healing process after delayed tooth replantation. Thirty Wistar (Rattus norvegicus albinus) rats were submitted to extraction of their upper right incisor. The teeth were maintained in a dry environment for 60 min. After this, the pulp was extirpated and the papilla, enamel organ and periodontal ligament were removed with scalpel. The teeth were divided into three experimental groups: Group I – teeth immersed in 20 ml of physiologic saline; Group II – teeth immersed in 20 ml of 2% acidulated phosphate sodium fluoride; Group III – teeth immersed in 20 ml of 15% propolis. After 10 min of immersion in the solutions, the root canals were dried and filled with calcium hydroxide paste and the teeth were replanted. The animals were euthanized 60 days after replantation. The results showed that similar external root resorption was seen in the propolis and fluoride groups. Teeth treated with physiologic saline tended to have more inflammatory root resorption compared with those treated with fluoride or propolis. However, the comparative analysis did not reveal statistically significant differences (P > 0.05) between the treatment modalities when used for delayed tooth replantation.     

人牙周膜成纤维细胞来源外泌体对大鼠延期牙再植术后牙根吸收的调控作用

目的: 探讨健康的人牙周膜成纤维细胞（hPDLFs）来源外泌体对大鼠延期牙再植术后牙根吸收的作用及其可能机制。方法: 分离提取hPDLFs来源的外泌体并鉴定。选择30只6周龄雄性SD大鼠,随机分为对照组和外泌体组,建立上颌第一磨牙延期牙再植术模型,牙脱位30 min后植回牙槽窝。对照组牙周膜局部注射40 μL汉克斯平衡盐溶液（HBSS）,实验组牙周膜局部注射40 μL含外泌体的HBSS。术后1、2、4周收样,苏木精-伊红（H-E）染色观察牙根表面吸收陷窝,抗酒石酸酸性磷酸酶（TRAP）染色观察破骨细胞数量,免疫组织化学染色观察牙周膜内骨保护素（OPG）的表达。采用SPSS 17.0软件包对数据进行统计学处理。结果: 鉴定表明提取的细胞外囊泡为外泌体。与对照组相比,hPDLFs来源的外泌体减少了延期牙再植术后牙根吸收陷窝的数量,降低TRAP阳性破骨细胞的表达（P<0.05）,促进牙周膜内OPG的表达（P<0.05）。结论: 延期牙再植术后,hPDLFs来源的外泌体减少了破骨细胞的数量,促进牙周膜内OPG表达,减少了再植术后的牙根吸收。     

Effect of root surface treatment with denusomab after delayed tooth replantation

Clinical Oral Investigations - To evaluate denosumab, a human monoclonal antibody that mimics the effects of osteoprotegerin in bone metabolism, as a topical treatment of root surface to be used...     

全脱位牙延期再植根面牙周膜不同去除方法的比较

目的:研究全脱位牙延期再植前去除其根面坏死牙周膜的有效方法.方法:取35颗因正畸需要拔除的健康右下颌第一前磨牙,室温下干燥保存超过1h,随机平均分为5组.①阴性对照组;②机械去除组:用手术刀片刮除根面坏死牙周膜;③化学去除组1以1％NaClO溶液浸泡实验牙5 min;④化学去除组2以2％NaClO溶液浸泡实验牙5 min;⑤化学去除组3以1％NaClO溶液浸泡实验牙10 min.然后用扫描电镜和组织学切片观察评价各组间牙周膜残留和牙骨质剥脱情况,采用SAS 8.02软件包对数据进行统计学分析.结果:牙周膜残留方面,阴性对照组显著高于机械去除组和3个化学去除组(P＜0.05),机械去除组显著高于3个化学去除组(P＜0.05),但3个化学去除组之间无显著差异.牙骨质缺损方面,机械去除组显著高于阴性对照组和3个化学去除组(P＜0.05);阴性对照组和3个化学去除组之间无显著差异.结论:在本实验条件下,机械去除法既无法去净根面坏死牙周膜,又会导致根面牙骨质层破坏.化学去除法能在有效去除根面牙周膜的同时,很好地保持牙骨质层的完整性,较机械去除法更佳,是一种较理想的方法.     

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF₂ conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF₂ solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF₂ for 5 min, rinsed in saline, immersed in 1% doxycycline HC1 for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF₂ solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

Effect of dexamethasone on root resorption after delayed replantation of rat tooth

The purpose of this study was to evaluate the effect of dexamethasone after delayed tooth replantation with specific regard to root resorption and ankylosis. In addition, the study was planned to elucidate further the usefulness of the model. Fifty-two maxillary first molar teeth were extracted from 26 Sprague-Dawley white female rats fed 0.4% beta-aminoproprionitrile for 3 days to facilitate the extraction. After extraction, the mesiobuccal root canals were endodontically treated under a microscope to prevent subsequent inflammatory resorption of pulpal origin and were assigned to three groups. Teeth in group 1, the dexamethasone group (n = 22), were demineralized in citric acid (1 min), washed, soaked in 1000 nM dexamethasone solution (3 min), air-dried, and replanted in the original sockets. Total extraoral treatment time for each tooth was controlled to 30 min. Teeth in group 2, the dried-only group (n = 22), were air-dried for 30 min after obturation without any surface treatment and replanted. Teeth in group 3, the immediate group (n = 8), were extracted, not root-filled and replanted immediately into their sockets. All experimental animals were killed at 3 weeks after replantation and evaluated histologically. Forty-three of the 52 teeth were available for histological interpretation. They consisted of six immediate, 18 dried-only, and 19 dexamethasone-treated teeth. The degree of progressive root resorption was significantly less in the dexamethasone-treated group than in the dried-only group (p < 0.05). The dexamethasone-treated group exhibited significantly more bone ankylosis than the dried-only group (p < 0.05). These results indicate that the topical use of dexamethasone may be of value in reducing the degree or rate of progressive root resorption secondary to traumatic avulsion and that the rat is a reasonable model for tooth replantation.     

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs.

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF2 conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF2 solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF2 for 5 min, rinsed in saline, immersed in 1% doxycycline HCl for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF2 solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

再植牙复合牙周膜细胞的实验研究

目的:研究体外培养的牙周膜细胞与牙根共同再植入人造牙槽窝内,其组织形成的能力与促进牙周再生的潜能。方法:拔除2只杂种狗的第三、第四前磨牙,得到牙周膜细胞并进行体外培养。拔牙后1个月,将体外培养的牙周膜细胞与自体牙根共同再植入右侧下颌无牙区的人造牙槽窝内,左侧下颌作为对照。再植2个月后,处死动物,标本制成石蜡切片,HE染色,光镜下进行组织学观察。结果:实验组标本中,在与近根尖部分牙根相对的一些区域可以看到垂直于骨表面的纤维束包埋于牙槽窝壁中。结论:即使被植入人造牙槽窝中,体外培养的牙周膜细胞仍保留了在体内形成类牙周膜组织的能力。     

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,     

自噬在延期牙再植术后炎症性牙根吸收中的作用研究

目的:观察大鼠延期牙再植术后自噬水平变化,探讨自噬在延期牙再植术后炎症性牙根吸收中的作用.方法:选取24只4周龄SD大鼠,拔除双侧上颌第一磨牙,干燥30 min后植回牙槽窝,术后1、3、7、28 d取材,染色观察炎症浸润情况、牙根表面吸收情况、肿瘤坏死因子α(TNF?α)、白细胞介素1β(IL?1β)等炎症因子表达及L...     

Proliferation,migration and apoptosis of periodontal ligament cells after tooth replantation

Oral Diseases (2010) 16 , 263–268 Objective: The aim of this study was to investigate the proliferation, migration and death of periodontal ligament (PDL) cells after tooth replantation. Materials and methods: Maxillary first molars were extracted from 4‐week‐old male (n = 28) Sprague–Dawley rats and immediately replanted, after which, proliferation, migration and death of PDL cells were investigated. Results: At 3 days after tooth replantation, many proliferative cell nuclear antigen (PCNA)‐positive PDL cells were observed on the alveolar bone side, but fewer on the root side. However, while a gradual decrease was observed in number of PCNA‐positive PDL cells on the alveolar bone side until 7 days, an increase was seen on the root side. At 3 weeks, cells labeled with PKH26 (fluorescent dye into plasma membrane) were located in the middle of the PDL space. However, these PKH26‐labeled cells did not spread to the surface of the cementum or the alveolar bone. TUNEL‐positive cells were observed on both the bone and root sides at 3 days. Number of apoptotic cells increased until 7 days on the bone sides, but decreased on root sides. Conclusion: These results suggest that both cell proliferation and apoptosis occur in different patterns and at different times to maintain regular spacing of the PDL after tooth replantation.     

Calcium hydroxide mixed with camphoric p-monochlorophenol or chlorhexidine in delayed tooth replantation

This study evaluated the repair process after delayed replantation of rat teeth, using calcium hydroxide (Ca(OH)2) mixed with camphorated p-monochlorophenol (CMCP), chlorhexidine 2% (CHX), or saline as temporary root canal dressing to prevent and/or control inflammatory radicular resorption. Thirty Wistar rats (Rattus norvegicus albinos) had their right upper incisor extracted, which was bench-dried for 60 minutes. The dental papilla, the enamel organ, the dental pulp, and the periodontal ligament were removed. The teeth were immersed in 2% acidulated-phosphate sodium fluoride solution for 10 minutes. The root canals were dried with absorbent paper cones and divided into 3 groups of 10 animals according to root canal dressing used: group 1: Ca(OH)2 + saline, group 2: Ca(OH)2 + CMCP, and group 3: Ca(OH)2 + CHX 2%. Before replanting, the teeth sockets were irrigated with saline. Histological analysis revealed the presence of inflammatory resorption, replacement resorption, and ankylosis in all 3 groups. Statistical analysis showed a significant difference between group 3 and the other groups. The use of Ca(OH)2 mixed with CMCP or CHX did not show an advantage over the use of Ca(OH)2 mixed with saline in preventing and/or controlling inflammatory resorption in delayed replantation of rat teeth.     

Immediate replantation of maxillary incisors in rats: effects of tooth immersion in sodium fluoride and subsequent removal of the periodontal ligament

The advantages and disadvantages of maintaining the periodontal ligament (PDL) in immediate replantation as well as chemical treatment of the root surface have been a matter of discussion because the vitality of such tissue in surgery is always questioned. This study evaluated the effects of conserving the tooth in sodium fluoride and the removal of the PDL before replantation of incisors in rats. There was more cementum-dentin resorption in the group with the PDL. The group without the PDL showed more discreet resorption, repair occurred through the newly formed bone tissue in the PDL space and ankylosis was more extensive than in the group with the PDL.     

Treatment of root surface in delayed tooth replantation: a review of literature

Abstract –  The time elapsed between a trauma and tooth replantation usually ranges from 1 to 4 h. The chances of root surface damage are higher when tooth replantation is not performed immediately or if the avulsed tooth is not stored in an adequate medium. This invariably leads to necrosis of pulp tissue, periodontal ligament cells and cementum, thus increasing the possibility of root resorption, which is the main cause of loss of replanted teeth. This paper presents a comprehensive review of literature on root surface treatments performed in cases of delayed tooth replantation with necrotic cemental periodontal ligament. Journal articles retrieved from PubMed/MedLine, Bireme and Scielo databases were reviewed. It was observed that, when there are no periodontal ligament remnants and contamination is under control, replacement resorption and ankylosis are the best results and that, although these events will end up leading to tooth loss, this will happen slowly with no loss of the alveolar ridge height, which is important for future prosthesis planning.     

Effect of propolis on proliferation and apoptosis of periodontal ligament fibroblasts

The most critical factors affecting the prognosis of an avulsed tooth are extraoral dry time and storage media used before replantation. Studies have analyzed different storage media to determine the ideal solution to preserve periodontal ligament (PDL) cell viability. Propolis has anti-inflammatory and antimicrobial properties, and has been previously suggested as a storage medium. The purpose of this study was to assess not only cell viability but also physiological health of PDL cells after exposure to propolis. PDL cells were exposed to different concentrations of propolis or Hanks balanced salt solution, and the apoptotic levels were determined using apoptosis assay and flow cytometry. Additional cell viability and proliferation were analyzed by XXT assay in dry and wet conditions. Propolis not only decreased apoptosis but also increased the metabolic activity and proliferation of PDL cells. This study suggests that propolis is a suitable storage medium for avulsed teeth.     

Use of vitamin C in delayed tooth replantation

This study evaluated microscopically the effects of root surface treatment with three different solutions in delayed rat teeth replantation. Central incisors from 30 rats (Rattus norvegicus, albinus Wistar) were extracted and left on a bench for 6 h. The pulps were extirpated and root canals were irrigated with 1% sodium hypochlorite. After endodontic treatment, the root surfaces of all teeth were submitted to a 10-min treatment with 1% sodium hypochlorite, changed every 5 min. The teeth were then rinsed with saline for 10 min and assigned to 3 groups with ten specimens each. Groups I, II and III were treated, respectively, with 2% acidulated-phosphate sodium fluoride, vitamin C solution and effervescent vitamin C (2 g, Redoxon. After root surface treatment, the teeth were filled with calcium hydroxide and replanted. The animals were sacrificed after 10 and 60 days. Group I (fluoride) presented the largest areas of replacement resorption and ankylosis. Comparing both vitamin C groups, Group III (effervescent vitamin C) yielded better results, showing more areas of ankylosis and replacement resorption than areas of inflammatory resorption.     

Effect of propolis on human fibroblasts from the pulp and periodontal ligament

Propolis, a flavonoid-rich product of honey comb, exhibits antibacterial and anti-inflammatory properties. In this study, we examined the tolerance of fibroblasts of the periodontal ligament (PDL) and dental pulp to propolis and compared with that of calcium hydroxide in vitro. Cells from human dental pulp and PDL were obtained from healthy third molars and subjected to various concentrations of propolis (0-20 mg/ml) and calcium hydroxide (0-250 mg/ml). The cell viability after propolis treatment was analyzed by crystal violet staining of the cells followed by spectrophotometric analysis. Data revealed that exposure of PDL cells or pulp fibroblasts to 4 mg/ml or lower concentrations of propolis resulted in >75% viability of cells. On the contrary, calcium hydroxide 0.4 mg/ml was cytotoxic and <25% of the cells were found to be viable. Further investigations may find propolis to be a possible alternative for an intracanal antimicrobial agent.     

完全脱位牙再植的牙髓、牙周膜愈合:从生物学基础到牙外伤指南

牙完全脱位又称牙撕脱伤,是一种严重的牙外伤,指在外力作用下,牙齿从牙槽窝中脱出,导致牙髓血运中断,牙周膜细胞暴露于体外。首选治疗方法是根据国际牙外伤协会(IADT,2012年)和美国牙髓病协会(AAE,2013年)修订的完全脱位牙再植治疗指南对患牙进行再植,以增大牙周膜愈合及牙髓血运重建的可能。但是完全脱位牙的预后受到多种临床因素影响。在某些情况下,即使按照指南进行规范治疗,完全脱位牙的术后并发症仍无法完全避免。因此,本文详细介绍牙外伤指南制定的相关生物学基础,结合临床病例,帮助临床医生理解和应用上述指南来治疗完全脱位牙及评估患牙的预后,以期为临床提供参考。