Orthograde retreatment failure with extruded MTA apical plug in a large periradicular lesion followed by surgical intervention: case report

Absence of periapical healing after orthograde retreatment using an apical plug with mineral trioxide aggregate (MTA) can require surgical intervention. A patient with a root-filled maxillary central incisor with chronic apical periodontitis and sinus tract was referred for endodontic retreatment. Excessive apical enlargement was verified, indicating an MTA apical plug placement; however, an unintentional extrusion of MTA occurred during this step. The root canal was filled with gutta-percha and sealer, and periodic recalls were scheduled. The sinus tract was observed after six months and the lesion remained unaltered, although the extruded MTA had resorbed; therefore, an apicoectomy and retrograde root-end filling with MTA were performed. Absence of sinus tract, normal clinical aspect, and complete repair of the lesion were observed at the two-year follow-up.     

手术方法和植骨对老年人根尖周病疗效影响与分析

目的：通过2年随访观察和临床检查，分析比较手术治疗方法和治疗后植入人工骨对老年根尖周病疗效的影响。方法：选择临床需行手术治疗老年根尖周病患者67例，患牙77颗，分3组分别采用根尖刮治术，根尖切除术或根尖倒充填术。部分病例术后填入人工骨。连续2年随访观察和临床检查手术治疗方法和植骨对疗效的影响。结果：根尖切除术疗效高于根尖倒充填术和根尖刮治术，植入人工骨对根尖周病术后愈合效果好。结论：根尖切除术和术后植入人工骨有助提高根尖周病治疗后成功率。     

Long-term survival of teeth in the posterior region after apical surgery

Oftentimes the discussion of long-term success rates and treatment modalities becomes a central issue in consultations with patients. The aim of this study was to retrospectively evaluate survival rates of teeth after apicoectomy in an established private practice for Oral and Maxillofacial Surgery in Kiel, Germany.All teeth treated with apicoectomy between 2001 and 2006 were included. Treatment success was previously defined as preservation of the tooth. Putative influence factors on success as kind and quality of endodontic treatment, additional intraoperative endodontic filling, inflammatory status, tooth mobility, and pre- and postoperative X-rays were further evaluated.A total of 149 teeth could be included. The mean observation period was 6.3 (SD: 4.4) years. In all, 48.3% of these teeth could be retained after a 10-year period. Teeth that received an additional retrograde root canal filling during surgery resulted in a significantly higher success rate (p = 0.0237) compared to those with orthograde root canal fillings or without additional endodontic treatment. The quality of endodontic treatment had no impact (p = 0.125).Our results suggest that apical surgery is a reliable procedure to treat and ensure the survival of symptomatic teeth in the posterior region for several years. A significant improvement was further determined for a retrograde filling.     

Apicoectomy with retrograde gutta-percha root filling

Sixty-four teeth were treated by means of apicoectomy with retrograde gutta-percha filling with the use of new instruments that we devised. The new instruments consisted of a biangle explorer, angle reamers, and angle files. Operations with this technique showed a success rate of 95.3% (61/64 teeth). We conclude that our technique for apicoectomy with retrograde gutta-percha filling is not only simple in procedure, but also shows excellent results.     

Biocompatibility of retrograde root filling materials: a review

The aim of a retrograde filling material is to fill the apical canal space and to obtain a hermetic seal between the periodontium and the root canal system. Several materials have been suggested for root-end filling including: amalgam, gutta-percha, zinc oxide-eugenol cements, glass ionomer cement, gold foil pellets, Cavit, composite resin and mineral trioxide aggregate (MTA). Super-ethoxy benzoic acid and MTA are the most suitable materials and provide better results in apicoectomy procedures than other filling materials. Unfortunately, the ideal material for this purpose has yet to be found. This article is a review of the biocompatibility of retrograde filling materials.     

Tissue response to glass ionomer retrograde root fillings

The periapical tissue response to glass ionomer cement retrograde root fillings was investigated both in the presence and in the absence of fillings in the root canals of eight upper incisor teeth of four monkeys. The pulps of the teeth were extirpated and one canal in each pair was filled with laterally condensed gutta-percha immediately after canal preparation. The other canal was prepared but left open to oral contamination. Apicectomies were performed on both teeth in each pair 1 week later, and glass ionomer cement retrograde root fillings were placed. After 5 months, the teeth and surrounding tissues were removed and prepared for histological examination. All four of the teeth without root canal fillings showed severe periapical inflammation, and bacterial were present in the interface between the dentine and the retrograde root filling. The teeth with root canal fillings showed little or no periapical inflammation. This study showed that adhesive retrograde root fillings were successful when the root canal was completely filled, but in the absence of a gutta-percha canal filling they failed to provide a seal.     

Retrograde root filling with composite and a dentin-bonding agent. 1.

A method is described, by which retrograde root filling with a composite resin can be performed. The cavity design is a slightly concave dissection of the apical part of the root, which is treated with the bonding agent Gluma followed by an application of Retroplast. Retroplast is a chemically curable composite containing silver for radiopacity and aerosil to obtain a suitable consistency. Endodontically treated teeth with a eugenol-containing root canal sealer did not affect the strength of the bond between Retroplast and apical dentin. A tight seal between the composite and the cavity surface was observed by light and SEM microscopy, and histology of tissue surrounding fillings placed in monkeys revealed absence of inflammatory cells around the filling and a close contact between filling and fibroblasts with collagenous fibers. In some cases, cementum and Sharpey's fibers formed in contact with the filling. Fillings placed in humans performed successfully in most cases, and the main causes of failure were either inadequate hemostasis during filling, or root fracture unnoticed by the time of filling. The retrograde technique promises a new treatment principle, with a root canal effectively sealed and the periapical ligament restored after apicoectomy.     

Retrograde root filling with composite and a dentin-bonding agent. 1

Abstract A method is described, by which retrograde root filling with a composite resin can be performed. The cavity design is a slightly concave dissection of the apical part of the root, which is treated with the bonding agent Gluma followed by an application of Retroplast. Retroplast is a chemically curable composite containing silver for radiopacity and aerosil to obtain a suitable consistency. Endodontically treated teeth with a eugenol-containing root canal sealer did not affect the strength of the bond between Retroplast and apical dentin. A tight seal between the composite and the cavity surface was observed by light and SEM microscopy, and histology of tissue surrounding fillings placed in monkeys revealed absence of inflammatory cells around the filling and a close contact between filling and fibro-blasts with collagenous fibers. In some cases, cementum and Sharpey's fibers formed in contact with the filling. Fillings placed in humans performed successfully in most cases, and the main causes of failure were either inadequate hemostasis during filling, or root fracture unnoticed by the time of filling. The retrograde technique promises a new treatment principle, with a root canal effectively sealed and the periapical ligament restored after apicoectomy.     

The sealing ability of amalgam used as a retrograde root filling in endodontic surgery

A dye penetration technique was used to investigate the sealing ability of amalgam retrograde root fillings in vitro. A factorial design was employed to determine the effect of amalgam fillings of 1, 2 and 4 mm in length with and without prior filling of the canals with gutta-percha. The results were compared with a group of teeth filled with laterally condensed gutta-percha alone and another with laterally condensed gutta-percha plus root resection but with no retrograde filling. It was concluded that increasing the length of the amalgam filling did not improve the seal, that prior filling of the canal did not improve the seal, that retrograde root fillings were no worse than laterally condensed gutta-percha alone and that root resection of teeth filled with laterally condensed gutta-percha without retrograde filling was no worse than those filled with laterally condensed gutta-percha without root resection or retrograde root filling.     

Periapikale Mikrochirurgie

The implementation of the surgical microscope, retrograde cavity preparation with ultrasound and the development of filling materials allow a more cause-focused and successful treatment of apical lesions. The prefix in the term periapical microsurgery involves more than just resection of the root tip. Different microsurgical techniques of apicoectomy are described with the benefits, contraindications and potential difficulties.     

An evaluation of the retrograde apical seal using dentine bonding materials

Summary. The purpose of this investigation was to compare in vitro retrograde apical leakage of four dentine bonding procedures with amalgam and hot burnished gutta-percha.
Single-rooted teeth were prepared using a standardized stepback flare technique with recapitulation. The teeth were obturated with gutta-percha and sealer using the lateral condensation technique and placed into a saline bath at 37°C for 30 days. The teeth were then randomly divided into seven groups of 22 teeth each. Groups I and II were apically bevelled, and dentine bonding agent with composite resin and dentine bonding agent with unfilled resin applied to the bevelled root faces, respectively. Groups III, V and VI were apically bevelled and prepared to accept a retrograde filling material of dentine bonding agent with composite resin, amalgam with cavity varnish and amalgam without cavity varnish, respective. Group IV had dentine bonding agent and unfilled resin applied to the apical third of the root, and Group VII was apically bevelled and the gutta-percha hot burnished. The teeth were then placed into a water bath at 37°C for 30 days, stained with silver nitrate and the linear dye penetration measured.
The lowest mean leakage value was recorded in Group I, i.e. dentine bonding agent and composite resin (0.31 mm), and the highest value was observed in group VII, i.e. hot burnished gutta-percha (4.60mm); the difference was statistically significant.     

Retrograde approaches in endodontic therapy

Abstract The routine use of retrograde fillings during apical surgery, as well as the material of choice for that purpose, have been debated. A retrograde filling is placed so as to seal an infected root canal causing periapical pathosis. Therefore, retrograde root canal fillings should be performed routinely during apical surgery regardless of the apparent technical quality of the root canal obturation, unless orthograde endodontic treatment is performed in conjunction with surgery. When orthograde treatment is not performed in conjunction with surgery. When orthograde treatment is not performed, retrograde root canal filling enhances the prognosis of apical surgery. An array of potential retrograde filling materials have been extensively investigated in vitro and in vivo. Once that the biocompatibility of the materials is confirmed a clinical comparison, rather than in vitro sealability studies, is the most valid evaluation method. Some of the difficulties encountered in long term clinical studies in patients may be avoided in animal studies. The review of the relevant literature of the past decade suggests that amalgam used in conjunction with cavity varnish is the retrograde filling material of choice. It must be stressed, however, that retrograde filling is not comparable to debridement and obturation of the entire root canal. Therefore, when the only way to approach the root canal is from the apical direction, rather than placing an apical retrograde filling, a retrograde endodontic treatment of the entire canal should be preferred, if it is feasible.     

A systematic review of in vivo retrograde obturation materials

Purpose The aim of this study was to answer the question: For patients requiring apicoectomy (apicectomy/root‐end resection) and retrograde (root‐end) obturation (filling), which retrograde obturation (root‐end filling) material(s) is/are the most effective, as determined by reduction in periapical radiolucency and elimination of signs and symptoms? Materials and methods A MEDLINE and a Cochrane search (two specified searches) were conducted to identify randomised (RCT) and nonrandomised controlled clinical trials (CCT), cohort studies (CS) and case‐control studies (CCS), published between 1966 and 2002, October week 4, conducted on humans, and published in English, German and French language, relating to retrograde obturation materials following apicoectomy. Results The MEDLINE and the Cochrane search identified 324 and 21 published articles, respectively. The Cochrane search identified three additional articles to the MEDLINE‐search articles. Fourteen studies met the inclusion criteria: two were RCTs, six were CCTs, none was a CS and six were retrospective CCSs. Nine of the 14 studies compared a new retrograde (root‐end)‐filling material to amalgam, 4 of the 14 studies compared orthograde root canal fillings to retrograde (root‐end) amalgam and the fourteenth study compared variations of a resin composite (Retroplast) when used in combination with the bonding agent Gluma (Bayer AG, Gluma 1 and 2). The two RCTs indicated that glass ionomer cement appeared to be equivalent to amalgam. The six CCTs indicated that orthograde filling with gutta‐percha and sealer was more effective than amalgam retrograde (root‐end)‐filling (one trial). Similarly, retrograde (root‐end)‐filling with (i) composite and Gluma (Bayer AG, Leverkusen, Germany) as bonding agent (one trial), (ii) reinforced zinc oxide eugenol cement (EBA cement) (Stailine, Staident, Middlesex, England; one trial) and (iii) gold leaf (one trial) appeared to be better than amalgam retrograde (root‐end)‐filling. Finally, gutta‐percha retrograde (root‐end)‐filling appears to be less effective than amalgam (one trial) and Retroplast with ytterbium trifluoride is better than Retroplast with silver, when they are both used with Gluma as bonding agent (one trial). Conclusions For the highest level of evidence (RCT) retrograde (root‐end)‐filling with glass ionomer cement is almost as effective as amalgam. However, there was a significant caveat as there were only two RCTs. At the next highest level of evidence (CCT), and given the additional caveat that there was only one controlled trial for each material, retrograde (root‐end) EBA cement, composite with Gluma and gold leaf, as well as orthograde gutta‐percha, may be more effective than retrograde (root‐end) amalgam filling. In conclusion, these results suggest that additional validating CCTs and RCTs are needed.     

In vitro study of the sealing ability of four retrograde filling materials

Abstract This in vitro study utilized India ink dye after clearing to evaluate the extent of apical microleakage following reverse filling procedures. Forty single-rooted human teeth divided into 4 groups were chemomechanically prepared and obturated, using the lateral condensation technique with gutta-percha and Grossman sealer. Following obturation, an apicoectomy was performed and retrograde cavities were filled with 4 different materials: Group A: amalgam and varnish; Group B: EBA cement; Group C: Ketac-cem®; Group D: hot-burnished gutta-percha. All teeth were immersed in India ink, decalcified, cleaned, examined through a stereomicroscope, and the depth of linear dye penetration was measured. Statistical analysis showed significantly less dye penetration with EBA cement and amalgam with varnish than with Ketac-cem and hot-burnished gutta-percha.     

Retrograde approaches in endodontic therapy.

The routine use of retrograde fillings during apical surgery, as well as the material of choice for that purpose, have been debated. A retrograde filling is placed so as to seal an infected root canal causing periapical pathosis. Therefore, retrograde root canal fillings should be performed routinely during apical surgery regardless of the apparent technical quality of the root canal obturation, unless orthograde endodontic treatment is performed in conjunction with surgery. When orthograde treatment is not performed, retrograde root canal filling enhances the prognosis of apical surgery. An array of potential retrograde filling materials have been extensively investigated in vitro and in vivo. Once that the biocompatibility of the materials is confirmed a clinical comparison, rather than in vitro sealability studies, is the most valid evaluation method. Some of the difficulties encountered in long term clinical studies in patients may be avoided in animal studies. The review of the relevant literature of the past decade suggests that amalgam used in conjunction with cavity varnish is the retrograde filling material of choice. It must be stressed, however, that retrograde filling is not comparable to debridement and obturation of the entire root canal. Therefore, when the only way to approach the root canal is from the apical direction, rather than placing an apical retrograde filling, a retrograde endodontic treatment of the entire canal should be preferred, if it is feasible.     

Biobond® for retrograde root filling in apicoectomy

Abstract— Comparative clinical and radiographic studies are presented on the results of apicoectomy alone and combined with retrograde root filling, using Biobond® and guttapercha respectively as filling material. The case series comprised 100 patients. The teeth treated were incisors and canines. The results were assessed from the clinical and radiographic findings at the last follow-up examination of the patients. The observation time was 24 months. It was found that there were no significant differences between the three groups of cases, satisfactory healing being achieved in 82% of the cases in which apicoectomy was performed alone, in 71% of the cases in which the procedure was combined with retrograde root filling, using guttapercha, and in 81% of the cases in which Biobond was the filling material.     

Apical sealing efficacy of two reverse filling techniques versus cold-burnished Gutta-percha

The apical seal produced by the cold-burnished gutta-percha method and two amalgam reverse filling techniques was investigated in an in vitro study using 36 extracted human single-rooted teeth. Following root canal obturation, 27 teeth were divided into three experimental groups and each group was subjected to one of the three following filling techniques: (a) cold-burnishing of gutta-percha; (b) amalgam reverse filling; and (c) amalgam reverse filling in conjunction with cavity varnish. The remaining nine teeth served as controls (4). The teeth were placed in methylene blue dye for a period of 1 wk, after which they were retrieved, washed, sectioned, and the apical dye penetration measured. The results showed that amalgam with cavity varnish demonstrated less dye penetration than the other experimental groups. The difference was statistically significant (p less than 0.0001).     

Utilization of gutta-percha for retrograde root fillings

Just as gutta-percha used with a root canal sealer is a recommended material for orthograde root fillings, it could similarly be the material of choice for retrograde fillings. Unfortunately, clinical accessibility and visibility do not always facilitate such a technique. The aim of this article is to present a new technique which enables retrograde fillings to be achieved with gutta-percha and a sealer. After the apex had been resected, a hole was drilled perpendicular to the plane of section of the apex about 1 mm coronally. The bucco-lingual depth required to reach the main canal was calculated. The cavity was then dried, coated with the sealer, and obturated with gutta-percha in accordance with thermo-mechanical compaction techniques. After excess filling material had been removed, the gutta-percha was cold burnished and the angles of the root were smoothed. Clinical cases illustrating healing of the periapical tissues are shown.     

The comparative leakage behavior of reverse filling materials

This study compares the in vitro apical seal achieved with thermoplasticized gutta-percha used with and without a sealer cement and that achieved with dental amalgam and a varnish liner following an apicoectomy and a Class I preparation of single root teeth. The teeth were immersed in methylene blue dye for 10 days, were sectioned longitudinally, and the amount of leakage was determined. No difference in leakage was found between the apical seals achieved with thermoplasticized gutta-percha used with a sealer cement and that obtained with dental amalgam with varnish. The leakage found with thermoplasticized gutta-percha used without a sealer cement was significantly greater.     

A preliminary study on the technical feasibility and outcome of retrograde root canal treatment

Aim  To investigate the technical feasibility and outcome of retrograde root canal treatment.
Summary  Endodontic access cavity preparation in abutment teeth may jeopardize the retention of the coronal restoration leading to prosthodontic failure. In such cases leaving the crown intact and performing retrograde root canal treatment might be an alternative approach. The potential to promote healing with retrograde endodontic treatment, and the technical feasibility to shape, clean and fill the canal was evaluated retrospectively. The study consisted of 21 incisors, canines and premolar teeth followed-up clinically and radiographically from 6 to 48 months. In 14 teeth the canals were completely negotiated. These cases were all judged as completely healed. In five cases no canal could be explored by files and a conventional ultrasonic root-end preparation and filling was performed. Two of these were classified as completely healed and three as 'uncertain'. In 2 two-rooted premolars a combination was performed with complete instrumentation of the buccal canal and the ultrasonic root-end preparation of the palatal root. One case was judged as a failure and the other was classified as completely healed. The results from this preliminary evaluation of retrograde root canal treatment are promising and merit a randomized clinical trial.
Key learning points • Abutment teeth with vital pulps may develop pulp necrosis and apical periodontitis in 10% of cases.
• Endodontic access preparation through an artificial crown may weaken its retention and jeopardize the longevity of a bridgework.
• Retrograde root canal treatment is often feasible in maxillary teeth.
• Results from this preliminary study suggest that treatment outcome for retrograde and orthograde root canal treatment is similar.