Long-term Complications of Previously Successful Regenerative Endodontic Procedures after Orthodontic Movement: A Report of 3 Different Complications after 4, 8, and 11 Years

There is a paucity of literature on late complications of regenerative endodontic procedures. The aim of this article was to report 3 cases of previously successful regenerative endodontic procedures with long-term follow-up that developed different complications after the application of orthodontic forces. In the first case, an 8-year-old female patient received a regenerative endodontic procedure in her previously intruded tooth (tooth no. 21) that had been rendered necrotic after a successful spontaneous repositioning procedure. The 5-year follow-up revealed uneventful healing, continuous root development, dentinal wall thickening, and regaining of pulp vitality for tooth no. 21. Four years later, the patient received orthodontic treatment with mild forces that lasted 2 years. The 11-year follow-up revealed severe external invasive cervical resorption, and the tooth had to be extracted. In the second case, a 6-year-old female patient suffered a lateral luxation injury in tooth no. 11. Six months after the injury, the tooth developed symptoms and discoloration and tested negative in pulp vitality testing. Single-step regenerative endodontic procedures were applied, and successful continuous root development, dentinal wall thickening, and apical closure were achieved at the 3-year follow-up. Two months after the initiation of orthodontic treatment, the tooth developed symptomatic apical periodontitis. Root canal treatment was performed to treat the disease, and the orthodontic treatment was continued. In the third case, a previously published successful regenerative endodontic procedure developed a perforating internal resorption 6 months after the application of orthodontic forces. The internal resorption was arrested with root canal treatment, the resorptive defect was repaired with bioceramic obturation, and the orthodontic treatment plan was modified. Previously successful regenerative cases might develop external invasive cervical resorption, regenerative tissue necrosis, or internal resorption after the application of orthodontic forces. Best practice/evidence-based guidelines on the appropriate orthodontic management of successful regenerative endodontic therapy teeth are lacking. Whenever possible, careful monitoring and partial or complete exclusion off orthodontic treatment might be necessary. In some cases, preventive root canal treatment before the initiation of orthodontic movement might be considered.     

Regenerative Endodontic Procedures for Traumatized Immature Permanent Teeth with Severe External Root Resorption and Root Perforation

External root resorption (ERR) is often a complication of traumatic injury to the teeth. Traditionally, external inflammatory root resorption is treated with calcium hydroxide. The outcome of ERR, especially replacement resorption, is unpredictable. The purpose of the present case report was to describe regenerative endodontic procedures (REPs) for 1 replanted avulsed tooth with severe external root resorption and root perforation (tooth #9) and 1 extruded tooth (tooth #8). A 9-year-old girl was referred for the treatment of teeth #8 and #9 4 months after the initial trauma. Clinical examination showed that tooth #9 had a sinus tract present near the periapical area, was tender to percussion and palpation, and did not respond to pulp sensibility tests. Tooth #8 responded to pulp sensibility tests. Periapical radiographic and cone-beam computed tomographic examination showed that tooth #9 had a periapical radiolucent lesion and severe ERRs with a root perforation. Tooth #9 was diagnosed with a necrotic pulp and symptomatic apical periodontitis. Regenerative endodontic procedures (REPs) were initiated. Tooth #8 became nonresponsive to pulp sensibility tests and developed a periapical lesion 12 months after REPs of tooth #9 and was also treated with REPs. The clinical symptoms and apical lesions resolved for both teeth after REPs. The severe ERRs were arrested, and root perforation was repaired for tooth #9. Teeth #8 and #9 underwent canal obliteration by hard tissue formation after REPs and were in function at 18 months and 30 months, respectively. REPs may be used to manage traumatized immature permanent teeth with a necrotic pulp and apical periodontitis associated with severe ERR and root perforation.     

Traumatic injuries of the teeth: current treatment modalities

Teeth that have been traumatized and exhibit craze lines, fracture into enamel, fracture into dentin, root fracture, concussion, or subluxation should be pulp tested 3 months after the accident. If the tooth has a vital pulp, root canal treatment likely will not be required. Teeth that have a crown-root fracture should receive immediate endodontic therapy, and--if needed--can be extruded orthodontically. An intruded tooth should have endodontic therapy the same day, with calcium hydroxide placed into the canal. Teeth that have been extruded, displaced in any direction, or totally avulsed must have the canal completely cleaned, shaped, and filled with calcium hydroxide within 1 or 2 weeks post trauma. Clinical research concerning traumatized teeth is ongoing, and it is incumbent upon each practitioner to keep abreast of the current literature. This review has discussed treatment modalities that are recommended at this time.     

猫下颌尖牙根管治疗对牙正畸移动的影响

目的：探讨经根管治疗牙的正畸移动可行性及牙根吸收的风险.方法：建立对经根管治疗牙进行正畸移动的动物模型,采用石膏模型测量、病理学和放射学方法评估正畸移动的距离及牙根吸收的程度.16只成年家猫的一侧下颌尖牙在全麻下开髓、拔髓,一次完成根管充填治疗术,随后在正畸弹簧的作用力（100～120 g）下向远中作倾斜移动.8周后测量石膏模型上牙移动的距离,以及根管治疗牙与正常牙的组织学和放射学牙根长度.应用SPSS11.0软件包进行数据分析,均数比较采用配对t检验.结果：实验结果显示,在相同正畸力作用下,根管治疗牙与正常牙移动距离相近（P＞0.05）;组织病理学显示,根管治疗牙牙根的长度比正常牙小（P＜0.05）,但在放射学上,两者的长度无统计学差异（P＞0.05）.结论：在本实验条件下,经根管治疗牙在正畸力作用下能与正常牙同样快速移动,组织学观察显示其根吸收的程度比后者略大.     

正畸治疗对根管治疗牙及对侧同名活髓牙根吸收影响的Meta分析

目的    分析正畸治疗对根管治疗牙及对侧同名活髓牙根吸收的影响。方法    计算机检索Cochrane Library、PubMed、Embase、Google Scholar、中国知网、万方等数据库,查找研究根管治疗牙经正畸治疗后牙根吸收情况的相关文献。应用Meta分析比较正畸治疗对根管治疗牙及对侧同名活髓牙根吸收的影响。结果    纳入了10篇相关文献。Meta分析结果发现,正畸治疗患者根管治疗牙根吸收情况与对侧同名活髓牙比较,差异无统计学意义（P > 0.05）。在男性正畸治疗患者中,根管治疗牙牙根吸收量小于对侧同名活髓牙,差异有统计学意义（P < 0.05）;而女性正畸治疗患者两侧牙根吸收量比较,差异无统计学意义（P > 0.05）。正畸治疗方式（拔牙矫治与非拔牙矫治）和牙位（前牙与后牙）对正畸治疗患者根管治疗牙及对侧同名活髓牙根吸收的影响比较,差异均无统计学意义（均P > 0.05）。结论    正畸治疗过程中移动根管治疗后的牙齿是一种相对安全的操作。     

Absence of apical resorption during orthodontic treatment on a tooth with a complicated crown fracture and root canal treatment: a case report

Root resorption often occurs after tooth trauma and may also occur during orthodontic tooth movement. This has been attributed to bacteria and inflammation or a combination of both aetiologies. The literature suggests that root canal treatment performed on a traumatized tooth that will concurrently or subsequently undergo orthodontic tooth movement may forestall the resorptive process. This case report provides evidence for this prevention and discusses the hypothesis for the absence of resorption on root-treated teeth.     

Regenerative Endodontic Treatment with Orthodontic Treatment in a Tooth with Dens Evaginatus: A Case Report with a 4-year Follow-up

Dens evaginatus is a developmental tooth anomaly in which an extra cusp or tubercle protrudes on the occlusal surface of the tooth along with some pulpal tissue. Because of the fragile nature of the protrusion, these teeth are often at risk of pulpal exposure. When this occurs in an immature tooth, regenerative endodontic treatment may be a good treatment approach to promote root formation. There is limited literature that documents the occurrence of orthodontic treatment in teeth that have undergone regenerative endodontic therapy using triple antibiotic paste. Here we present a case of an immature premolar tooth with dens evaginatus that was diagnosed with pulp necrosis and chronic apical abscess. The tooth was treated with regenerative endodontic treatment; after which, the patient received orthodontic treatment with fixed appliances for 2 years. The tooth responded favorably to the regenerative endodontic treatment and orthodontic tooth movement. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth with evidence of periapical healing with stunted root development. The tooth remained asymptomatic even after 4 years. The regenerative endodontic procedure (REP) was successful in treating an immature permanent premolar with pulp necrosis and apical periodontitis with dens evaginatus. In this case, the tooth treated with an REP responded to orthodontic treatment similar to the nonendodontically treated teeth. Further studies are recommended to clarify the precise effects of orthodontic treatment on teeth treated with an REP.     

Conservative management of a combined endodontic-orthodontic lesion.

Pulp injury may occur during orthodontic tooth movement particularly in previously traumatized teeth. Therefore the management of such cases requires specific therapeutic considerations. An extensive periradicular lesion was detected in an orthodontically treated maxillary incisor with an uncertain history of a previous traumatic incident. Conservative endodontic therapy resolved the periradicular lesion thus enabling the orthodontic treatment to continue uneventfully. It is essential to closely monitor the patients undergoing orthodontic treatment and those who are in retention, particularly if a history of trauma is suspected.     

Root resorption and apical breakdown during orthodontic treatment of a maxillary lateral incisor with dens invaginatus

Abstract— A 13-year-old girl was referred for endodontic treatment of a maxillary right lateral incisor with root resorption and apical radiolucency after orthodontic treatment. Radiographically the tooth had an invagination canal (Oehlers' Type III) and responded positively to pulp testing. The invagination canal extending to the lateral resorption was opened. Vital bleeding tissue was found, and the canal was cleaned and obturated. The pulp in the main root canal remained vital. The radiolucent lesion gradually decreased during the 3-year follow-up. The bone resorption seen here, despite vital tissue in the invagination canal, was probably due to osteoclastic activity caused by a low grade chronic infection, influenced by an injury-induced inflammation in the periodontiurn during orthodontic treatment.     

Guided Endodontics: Use of a Sleeveless Guide System on an Upper Premolar with Pulp Canal Obliteration and Apical Periodontitis

Guided endodontics has been used for the treatment of anterior teeth with a successful outcome. This approach is not only limited to anterior teeth because it can also be used for the treatment of premolars and molars. However, in such cases, space may be a limitation because a long bur has to be used in addition to the guide being placed on top of the teeth. The aim of this case report was to present a novel guided endodontics technique using a sleeveless 3-dimensional–printed guide. This design can reduce vertical space, allowing an open view of the tooth and irrigation during drilling. A 46-year-old female patient consulted the endodontic department with intermittent pain around tooth #5. Tooth #5 presented pain upon percussion and responded negative to a cold test. The initial periapical radiograph revealed an apical radiolucency with pulp canal obliteration. Clinically, there was no sinus tract. The tooth was diagnosed with pulp necrosis and symptomatic apical periodontitis. Guided endodontic treatment was performed with a sleeveless 3-dimensional–printed guide and long neck carbide bur with a head diameter of 1 mm to drill a minimally invasive access cavity up to the root canal. A completely healed apical area of tooth #5 was visible after 1 year on periapical radiographs. This technique seems to be a promising alternative in comparison with the conventional guided endodontic guide design for the negotiation of pulp canal obliteration in cases in which vertical space is limited.     

Apexogenesis after initial root canal treatment of an immature maxillary incisor – a case report

Aim To present a case where a traumatized, immature tooth still showed capacity for continued root development and apexogenesis after root canal treatment was initiated based on an inaccurate pulpal diagnosis. Summary Traumatic dental injuries may result in endodontic complications. Treatment strategies for traumatized, immature teeth should aim at preserving pulp vitality to ensure further root development and tooth maturation. A 9‐year‐old boy, who had suffered a concussion injury to the maxillary anterior teeth, was referred after endodontic treatment was initiated in tooth 21 one week earlier. The tooth had incomplete root length, thin dentinal walls and a wide open apex. The pulp chamber had been accessed, and the pulp canal instrumented to size 100. According to the referral, bleeding from the root made it difficult to fill the root canal with calcium hydroxide. No radiographic signs of apical breakdown were recorded. Based on radiographic and clinical findings, a conservative treatment approach was followed to allow continued root development. Follow‐up with radiographic examination every 3rd month was performed for 15 months. Continued root formation with apical closure was recorded. In the cervical area, a hard tissue barrier developed, which was sealed with white mineral trioxide aggregate (MTA). Bonded composite was used to seal the access cavity. At the final 2 years follow‐up, the tooth showed further root development and was free from symptoms. Key learning points

• ? Endodontic treatment of immature teeth may result in a poor long‐term prognosis.
• ? The pulp of immature teeth has a significant repair potential as long as infection is prevented.
• ? Treatment strategies of traumatized, immature permanent teeth should aim at preserving pulp vitality to secure further root development and tooth maturation.
• ? Radiographic interpretation of the periapical area of immature teeth may be confused by the un‐mineralized radiolucent zone surrounding the dental papilla.

     

Use of a removable splint in the treatment of subluxated, luxated and root fractured anterior permanent teeth in children

Aim: The aim of this study was to evaluate the prognosis of subluxated, luxated and root fractured teeth in children treated by removable splints, designed to stabilize mobile anterior teeth and eliminate occlusal trauma due to malocclusion. Material and methods: A total of 227 traumatized anterior teeth (91 subluxated, 105 luxated and 31 root fractured teeth) treated with a removable splint were observed for 3 years. The traumatized teeth were from 79 children aged between 6–12 years (mean 8 years 5 months). If a traumatized tooth was extremely mobile, a fixed splint was first made before the impression was taken for the removable splint. Two weeks after completion of the removable splint treatment, an impression was taken again to evaluate the occlusal relationship of pre‐ versus post‐treatment of removable splint. Results: The treatment period with a removable splint averaged 3 weeks in subluxated teeth, 3–5 weeks in luxated teeth, 4–6 weeks in apical third root fracture injuries, and more than 5 weeks in middle third root fracture injuries. All the subluxated teeth and 74.1% of the luxated teeth maintained their pulp vitality during the 3‐year follow‐up period. Two of 21 (9.5%) apical third root fracture teeth and three of five (60%) middle third root fracture teeth had pulp necrosis in the coronal fragments. Internal resorption was not found in any of the traumatized teeth. External replacement resorption was not found in subluxated and luxated teeth. All the root fractured teeth displayed transient external resorption around the fracture lines. The surface resorption appeared to be self‐limiting and not to threaten the retention of the tooth. Inflammatory resorption was observed in teeth with pulp necrosis, but in all cases this was reversed with endodontic treatment. Eight of 23 (39%) apical third root fractured teeth displayed replacement resorption in their apical fragments, but the resorption was not serious enough to extract the tooth. No obvious alteration in the occlusal relationship was found comparing pre‐ and post‐treatment casts. The removable splints appeared to positively affect healing after traumatic injuries, as evidenced by the low number of complications at the 3‐year follow‐up period.     

外伤及根管治疗后牙齿正畸移动研究进展

临床上,对病损患牙的正畸牙移动越来越多见,尤其是外伤及根管治疗术后的患牙,其牙髓坏死、牙根吸收等问题也受到重视。如何减少这些情况的发生,安全、有效地移动患牙,成为学者们研究的热点。文章就近年来国内外学者对外伤及根管治疗术后患牙的正畸牙移动时机、结果等做一综述,以期为患牙正畸移动的进一步研究提供理论依据。     

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??Clinically??more and more orthodontic teeth movement has been observed in the affected teeth??especially after trauma and root canal treatment??RCT??. The problems of pulp necrosis and root resorption have also been paid attention to. Then??how to reduce the occurrence of these cases and move the affected teeth safely and effectively has become the research focus of the scholars. In order to provide theoretical basis for further research in orthodontic tooth movement of affected teeth??this review will make a summary mainly in the time and result of orthodontic tooth movement of traumatised and RCT teeth.     

正畸矫治对根管治疗牙齿牙根吸收程度影响的CBCT研究

目的利用CBCT评价正畸治疗对根管治疗牙齿牙根吸收程度的影响。方法选择上下颌牙齿轻中度拥挤的成年患者16例,患者上颌前牙中至少有一颗已行根管治疗。使用0.558 8 mm槽沟的MBT托槽进行非拔牙矫治。于治疗前、后分别拍摄头颅CBCT,并分别测量根管治疗牙齿以及对侧同名牙齿的长度。采用配对t检验进行统计分析。结果 16例患者一共有18颗上颌前牙接受过根管治疗,其中包括6颗中切牙,8颗侧切牙,4颗尖牙。平均治疗时间为(18.3±2.6)个月。治疗前,已行根管治疗牙齿牙根平均长度(22.68±2.14)mm;治疗后,牙根平均长度为(21.98±2.05)mm。治疗前,对侧同名活髓牙牙根平均长度(22.61±2.01)mm;治疗后,牙根平均长度为(22.01±2.37)mm。两组差别无统计学意义。按照牙位单独分析,亦无统计学差异。结论利用CBCT能够很好地观察正畸治疗后牙根吸收的情况。在轻中度拥挤非拔牙的病例中,正畸治疗并不会增加上颌前牙已行根管治疗牙齿牙根吸收的风险。     

Ingrowth of Mineralized Tissue into the Root Canal of Immature Permanent Teeth after a Traumatic Injury: A Report of 3 Cases

The aim of this case series was to describe the endodontic management of 3 immature permanent teeth that sustained traumatic injuries and subsequently presented with complete ingrowth of mineralized tissue into the canal space. Ingrowth of bone/mineralized tissue into the canal has been considered a poor long-term outcome with an inherent risk of ankylosis. In cases 1 and 2, no endodontic treatment was undertaken, except for emergency management requiring splinting. The cases were followed for 36 and 23 months, respectively. No ankylosis was evident over the review period, and normal teeth eruption was apparent. In case 1, the tooth was treated orthodontically and was responsive to pulp sensibility testing. In both cases, there was an appearance of an internal periodontal ligament–like space on the inner root wall of the canal. In case 3, 2 years postinjury, pulp necrosis and apical periodontitis occurred, and the tooth was managed with regenerative endodontic treatment consistent with the European Society of Endodontology and the American Association of Endodontists guidelines/recommendations for a regenerative procedure. The case was followed for 8 years after regenerative endodontic treatment. No ankylosis was noted with normal eruption of the teeth. The tooth was responsive to pulp sensibility testing despite the ingrowth of mineralized tissue, which was confirmed clinically.     

Use of 3-dimensional–Printed Guide in Hemisection and Autotransplantation of a Fusion Tooth: A Case Report

Three-dimensional (3D)-printed guides have been used in endodontics to prepare a conservative access, locate calcified or missing canals, and perform precisive osteotomy in apicoectomy. Here, we present the treatment of a fusion tooth by combining 3D printing technology and endodontic intervention in a 10-year-old patient. The bifid crown of a maxillary right lateral incisor #7 had caused esthetic concerns and malocclusion. Clinical and radiographic examinations showed that #7 is fused with a supernumerary tooth with 2 independent root canals. The fusion involved the entire crown and the coronal and middle roots. Because of financial constraints, a multidisciplinary approach involving endodontic, orthodontic, and prosthodontic treatment was excluded. We hemisectioned the tooth intraorally with a 3D-printed guide, extracted the supernumerary tooth, and transplanted tooth #7 to a position with improved esthetics and occlusion. A 3D-printed tooth replica was used to prepare the recipient site for autotransplantation. At the 6-month follow-up, tooth #7 was diagnosed with pulp necrosis and asymptomatic apical periodontitis. Root canal treatment of tooth #7 was completed, and osseous healing was observed 8 months later. The patient had no clinical symptoms and was satisfied with the outcome 14 months after hemisection and transplantation. The open space between teeth #7 and #8 was closed without orthodontic treatment. We present an alternative option to treat a fusion tooth in young patients who do not opt for other treatment options because of their stage of development or for socio-economic reasons. Techniques in modern endodontics, such as cone-beam computed tomographic imaging and 3D printing, should be adapted when it is beneficial to patients.     

Regenerative endodontics--biologically-based treatment for immature permanent teeth: a case report and review of the literature

Background: A paradigm shift in the treatment of immature, necrotic teeth has occurred with biologically‐based principles and regenerative endodontic protocols replacing traditional ‘apexification’ procedures. Preliminary research suggests that stem and progenitor cells from the pulp and/or periodontium contribute to continued root development when regenerative procedures are followed. Methods: A mandibular premolar tooth with a chronic periapical abscess was irrigated with sodium hypochlorite with minimal instrumentation and then dressed with tri‐antibiotic paste consisting of ciprofloxacin, metronidazole and amoxicillin. At a subsequent visit a blood clot was evoked in the canal by irritating periapical tissues and the canal sealed with mineral trioxide aggregate, glass ionomer cement and composite resin. Results: Resolution of apical periodontitis and the draining sinus, continued root maturation and apical closure occurred over an 18‐month period. The tooth became responsive to pulp sensibility testing. Conclusions: It is important that dentists recognize the potential of regenerative endodontics in the treatment of necrotic, immature teeth. Initial management should involve irrigation with sodium hypochlorite only. Intra‐canal medicaments, such as calcium hydroxide, are contraindicated as they inhibit further root growth. This report uses a variation of the tri‐antibiotic paste currently recommended for regenerative procedures that avoided the discolouration of the crown associated with current protocols. Regenerative endodontics with continued root growth may reduce the risk of fracture and premature tooth loss associated with traditional ‘apexification’ procedures where the root remains thin and weak.     

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。     

Intrusive luxation: a case report

Abstract –  Intrusive luxation is one of the most severe types of dental trauma. The occurrence of pulp necrosis in intruded teeth with open apices is 100%. The risk of development of inflammatory or replacement root resorptions is high. Thus, endodontic intervention is required soon after the occurrence of trauma, in an attempt to prevent or delay the appearance of such lesions. On the other hand, the access to the root canal is difficult, as the crown is intruded. A multidisciplinary approach comprising Surgery, Orthodontics and Endodontics is required to allow exposure of the crown, orthodontic extrusion and onset of endodontic therapy. The patient GCSA, aged 15 years, attended the community project 'Lugar de dente é na boca' ('teeth should be in the mouth') of the Federal University of Goiás, Brazil, 1 week after complete intrusion of the right maxillary central incisor. Radiographic examination revealed that the incisal edge of this tooth was at the level of the crown-root interface of the adjacent teeth. After surgical exposure of the crown, pulp sensitivity was evaluated and was found to be negative. After onset of endodontic therapy, the patient was referred for orthodontic extrusion of the intruded tooth. Successive changes of root canal dressing were performed and the root canal was definitely obturated at 3 years and 6 months after onset of treatment. The present paper reports on a case of severe intrusive luxation, discusses the different treatments recommended for repositioning of traumatically intruded teeth, and questions the ideal period of maintenance of calcium hydroxide dressing in the root canal, in an attempt to prevent the occurrence of root resorption and repair any existing resorption.