Search

Aim: Orthograde retreatment after failed apicectomy maybe a treatment alternative to endodontic resurgery. The purpose of this study was to examine the clinical outcome of orthograde endodontic retreatment after failed apicectomy. Methodology: Success was rated radiographically in 191 cases of orthograde retreatment after failed apicectomy that were treated in a private practice with a documented recall of at least 12 months. The radiographs were rated individually by two observers, in cases of disagreement a consensus was reached by joint discussion with a third observer. Success or failure were evaluated according to previously described criteria. The success rate and the median survival were calculated using the Kaplan–Meier survival analysis. The log rank test was used to evaluate the effect of prognostic factors/predictors. Hazard ratios of predictors were analysed using Univariate Cox Proportional Hazard regression analysis. Results: The mean follow‐up of the included 191 patients (124 females, 67 males) was 32.13 (±23.68) months and the median was 25 months. The overall recall rate was 54%. Cohen Kappa analysis revealed nearly perfect agreement between both observers (k = 0.81; p = 1.0). The overall percentage of success was 84.82% (complete healing 79.06%, incomplete healing 5.76%). The median survival was 86 months (95% CI: 56–86). None of the selected predictors had an influence on the treatment outcome (p >.05). Conclusions: Orthograde retreatment should be considered a valuable treatment option after failed apicectomy. A surgical endodontic retreatment can still be a treatment option after orthograde retreatment to obtain outcome for the patient. [ABSTRACT FROM AUTHOR]

Aims: To evaluate and compare the treatment outcome of root filled teeth with apical periodontitis treated either non‐surgically or by endodontic microsurgery, and to assess the influence of an intra‐radicular post, clinical and demographic factors. Methodology: Clinical and radiological data from 1157 patients with apical periodontitis in previously root filled teeth treated by postgraduate students at the Department of Endodontics, University of Oslo, between September 2010 and January 2020 with recall data at least 11 months from completion were studied. Surgical cases were scored using the Rud/Molven criteria and grouped into success, uncertain or failure at control. Non‐surgical cases were scored with the periapical index (PAI) and similarly grouped into success, uncertain or failure at control. Chi‐square analyses were used for comparison of subgroups of teeth treated and logistic regression analyses for assessment of the influence of clinical variables. Results: Non‐surgical retreatment was performed on 351 teeth and 107 teeth were treated with endodontic microsurgery, with overall success rates of 65.5% and 77.6%, respectively. The difference was statistically significant. Teeth with an intra‐radicular post treated non‐surgically (n = 30) were successful in 73.3% of cases, whereas teeth with intra‐radicular post treated with endodontic microsurgery (n = 30) had a lower, 66.7% success rate. The distribution of tooth groups (anterior, premolar and molar) differed significantly between surgical and non‐surgical cases, with maxillary anterior and premolar teeth more often treated surgically. Non‐surgical retreatment cases were significantly influenced by patients' age (older patients had poorer outcome) and pre‐operative PAI score (negatively correlated with outcome). Surgical cases were not significantly influenced by the factors studied here. Conclusions: The tooth type differed significantly for teeth treated by surgical versus non‐surgical methods. Microsurgical treatment with apicectomy and retrograde filling showed significantly better treatment results than non‐surgical retreatment of teeth with apical periodontitis, whereas treatment outcome in teeth with posts after non‐surgical treatment tended to be better than after surgical treatment. Outcome of non‐surgical retreatment was negatively influenced by older age and higher pre‐operative PAI score. [ABSTRACT FROM AUTHOR]

This study evaluated the reliability of sealer penetration measurement methods used with confocal laser scanning microscopy in correlation with the percentage of residual root filling and examined the effect of residual root‐filling material on dentine penetrability after retreatment. Extracted teeth were randomly divided into different groups according to the obturation sealer used (n = 6); BioRoot RCS; MTA Fillapex; Bio‐C and AH Plus. Root‐filling material was removed before the secondary chemo‐mechanical preparation and obturation using fluorescein labelled AH Plus. Multiple micro‐computed tomography scans were obtained followed by confocal laser scanning microscopy to measure the penetration of the labelled sealer into the dentinal tubules using four different methods. Measuring sealer penetration into radicular dentine using the penetration percentage method was found to be the most reliable. Dentine penetrability during retreatment did not seem to be affected by the type of residual root‐filling material. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to explore the influence of a framing effect in retreatment decision‐making of a root‐filled tooth with asymptomatic apical periodontitis (AP). Method: Two variants of a questionnaire were created in which the factual information about a root filled with AP was identical. The options in the first variant were framed in favor to wait and see (FW) and those in the other variant were framed in favor of retreatment (FR) Two hundred and forty‐eight volunteers were by chance given one of the two versions and were asked to choose between having retreatment or to wait and see. Results: Of the 125 participants given the FW version, 69 (55.2%) chose to wait and see while out of the 123 participants who were given the FR version, 38 (30.9%) made the alike choice (p =.0002). Conclusion: A framing effect is likely to play an essential role in endodontic retreatment decision‐making of root‐filled teeth with asymptomatic apical periodontitis. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the impact of kinematics and irrigation protocols on the extrusion of apical debris during removal of different obturation techniques. A total of 144 single‐rooted teeth were instrumented and obturated with Thermafil+AH Plus, Thermafil+AH Plus Bioceramic and single gutta‐percha cone+AH Plus Bioceramic. Samples were divided according to the retreatment kinematics: continuous rotation or Jeni motion. Each sub‐group was subjected to conventional irrigation or irrigation activated by EDDY. Extruded debris was collected in Eppendorf tubes, weighted and retreatment time was digitally recorded. Data were analysed with two‐way ANOVA (p < 0.05). Debris extrusion was not significantly different between all groups. EDDY activation system and CanalPro Jeni required significantly longer time compared with other groups to remove Thermafil+AH Plus and single cone+AH Plus Bioceramic. Within current limitations, obturation technique, irrigation protocol and kinematics tested had no influence on apical extrusion debris, while they significantly impacted the retreatment time. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To evaluate how additional information from Cone Beam CT (CBCT) impacts on periapical assessment and treatment planning based on clinical examination and periapical radiographs (PR) in cases followed up five to eleven years after surgical endodontic retreatment (SER). Methodology: Patients receiving SER during 2004–2010 were reinvited for follow‐up examination including clinical examination, PR, and CBCT. In total, 108 patients (119 teeth) were reinvited, 74 patients (83 teeth) accepted to participate. Three observers initially assessed PR according to the four‐scaled, increasing disease severity criteria by Rud et al. (International Journal of Oral Surgery, 1, 1972 and 195) and Molven et al. (International Journal of Oral and Maxillofacial Surgery, 16, and 432): ‘Radiographic assessment A’. By including clinical information ‘Treatment plan A’ was made as follows: 1) no treatment, 2) further observation, 3) SER reoperation (SER‐R), or 4) extraction. Hereafter, the CBCT volume was assessed and the information incorporated for ‘Radiographic assessment B’ followed by ‘Treatment plan B’. Agreement between radiographic assessments and between treatment plans was recorded and assessed statistically by Stuart–Maxwell test for marginal homogeneity. Results: Nine teeth had been extracted; thus, the final analysis included 74 teeth (66 patients). The radiographic assessment was changed as a result of the CBCT evaluation in 38 cases (51.4%), of which 35 (47.3%) were to a higher Rud & Molven score, P < 0.001. The treatment plan was changed for 18 teeth (24.3%). For 14 teeth (18.9%), the change was from no treatment or further observation to a more invasive treatment plan (SER‐R or extraction), P = 0.005. Conclusion: The use of CBCT for long‐term follow‐up after SER led to more cases diagnosed with persisting or recurrent apical periodontitis and hence often to the recommendation of a more invasive treatment modality. [ABSTRACT FROM AUTHOR]

The specificity of retreating immature teeth involves generally a broadly wide open apex and/or an inverted root canal conicity (apical opening wider than the root canal orifice), a periapical pathology leading often to a continuous canal exudation and thin and fragile dentinal walls. Nonsurgical endodontic retreatment of immature teeth consists at first in removing coronal and root canal iatrogenic obstructions in order to regain total canal patency. Apexification is then the treatment of choice, preceding a final gutta-percha obturation. The present article outlines a step-by-step rational approach to the root canal retreatment of immature teeth, pertaining to their biomechanical and pathological specificity. [ABSTRACT FROM AUTHOR]

Abstract – Endodontic retreatment decision-making must include an appraisal of the costs of the different strategies proposed. In addition to direct costs, postoperative discomfort may have other consequences in terms of time off work, unscheduled visits and suffering. To establish a foundation for the appraisal of such indirect and intangible costs the present study was set up in which patients' assessments of pain and swelling after surgical and nonsurgical retreatment procedures were recorded. Ninety-two patients with 95 root-filled incisors and canine teeth exhibiting apical periodontitis were included in the study. The mode of retreatment was randomly assigned. Each day during the first post-treatment week patients assessed their degree of swelling and pain on horizontal 100-mm visual analog scales (VAS). The scales ranged from “no swelling” to “very severe swelling” and “no pain” to “intolerable pain”, respectively. Consumption of self-prescribed analgesics and time off work were also recorded. Significantly more patients reported discomfort after surgical retreatment than after nonsurgical procedures. High pain scores were most frequent on the operative day while swelling reached its maximum on the first postoperative day followed by progressive decrease both in frequency and magnitude. Postoperative symptoms associated with nonsurgical retreatment were less frequent but reached high VAS values in single cases. Analgesics were significantly more often consumed after periapical surgery. Patients reported absence from work mainly due to swelling and discoloration of the skin. This was found to occur only after surgical retreatment. Conclusively, surgical retreatment resulted in more discomfort and tended to bring about greater indirect costs than nonsurgical retreatment. [ABSTRACT FROM AUTHOR]

Abstract Aim To describe the role of calcium hydroxide in infection control during complex endodontic retreatment. Summary A case is presented in which two conventional endodontic treatments and two surgical interventions failed to bring periapical healing. Despite this history, a further conventional treatment augmented by long-term disinfection with calcium hydroxide finally delivered a successful outcome. Key learning points • Periapical healing follows proper intracanal infection control. • Despite repeated surgical and nonsurgical intervention, careful retreatment can often bring healing. • Calcium hydroxide has long-acting antimicrobial and soft-tissue dissolving activity. It is a helpful adjunct in endodontic retreatment. [ABSTRACT FROM AUTHOR]

Abstract Kvist T, Reit C. The perceived benefit of endodontic retreatment. International Endodontic Journal , 35 , 359–365, 2002. Aim There is substantial variation amongst dentists in the management of symptom-free periapical lesions in root-filled teeth. It has been suggested that this variation can be understood as clinicians’ choice of different cut-off points on a continuous periapical health scale (the ‘Praxis Concept (PC) theory’). Based on this suggestion, an individual’s inclination to propose retreatment can be expressed in the Retreatment Preference Score (RPS). In the present study it was hypothesized that: (i) the PC theory is valid amongst experienced endodontists; and that (ii) interindividual variation in RPS can be explained by a corresponding variation in the perceived benefit of endodontic retreatment. Methodology The RPS was determined for 16 experienced Swedish endodontists. The retreatment benefit (RTB) was defined as the gain in utility when a root-filled tooth with a persistent periapical lesion (‘health state B’) moved to a state where the lesion had healed (‘health state A’). For each individual the utility values of the two health states were measured by means of the standard gamble technique. Results The RPS and RTB were found to be subjected to substantial inter- and intrarater variation. The decision makers acted in accordance with the PC theory. No significant correlation between RPS and RTB was detected. Conclusions Findings suggest that the PC theory is valid amongst endodontic experts. The study did not support the notion that the more potential utility that could be produced, the more the individual dentist should tend to perform retreatment. However, alternative consequentialist strategies focusing low risk taking may be involved. [ABSTRACT FROM AUTHOR]

Aim The objectives of the present study were to: (i) evaluate the consensus, if any, amongst dental schools, students and their instructors managing the same clinical cases, all of which involved endodontically treated teeth; and (ii) determine the predominant proposed treatment option. Methodology Final year students, endodontic staff members and instructors of 10 European dental schools were surveyed as decision makers. Fourteen different radiographic cases of root canal treated teeth accompanied by a short clinical history were presented to them in a uniform format. For each case the decision makers were requested to: (i) choose only one out of nine treatment alternatives proposed, from ‘no treatment’ to ‘extraction’ via ‘retreatment’ and ‘surgery’ (ii) assess on two 5-point scales: the difficulty of making a decision, and the technical complexity of the retreatment procedure. Results The results indicate wide inter- and also intra-school disagreements in the clinical management of root canal treated teeth. Analysis of variance showed that the main source of variation was the ‘school effect’, explaining 1.8% (NS) to 18.6% (P< 0.0001) of the treatment variations. No other factor explained as much variance. Decision difficulty was moderately correlated to technical complexity (Pearsons' r ranging from 0.19 to 0.35, P< 0.0001). Conclusions No clear consensus occurred amongst and within dental schools concerning the clinical management of the 14 cases. The lack of consensus amongst schools seems to be due mainly to chance or uncertainty, but can be partly explained by the ‘school effect’. [ABSTRACT FROM AUTHOR]

The present communication describes the endodontic retreatment of a rare four-rooted maxillary second molar. A 25-year-old patient was referred to our dental practice requesting an apicoectomy because of continuous and permanent pain reaction six months after the first endodontic treatment. The sent radiograph demonstrated three filled root canals (one mesial, two distal) and four radiographically superimposing roots (two mesial, two distal). Due to the diagnosed chronic apical periodontitis and based on the visible untreated root canal, we decided to endodontically re-treat the quadrangular tooth against the referred apicoectomy. In the first session, only the previously untreated mesiopalatal root canal was mechanically prepared and filled with a corticosteroid- and tetracycline-containing paste. After two symptom-free weeks, the gutta-percha was removed from the other canals and calcium hydroxide was applied. Another two weeks later, the four root canals, whose orifices were "irregular quadrilateral" shaped on the pulp chamber floor representing Versiani Type A, were obturated. After the verification of this rare anatomy by cone beam computed tomography, the tooth was classified as Christie's radicular type II. One characteristic of this type is parallel running buccal and palatal roots, which caused a radiographic superimposition and probably led to the endodontic mistreatment in the first case. [ABSTRACT FROM AUTHOR]

To explain dentists' variation in endodontic retreatment decision making a praxis concept (PC) has been generated. PC assumes that practitioners operate along a health continuum. Various periapical conditions are then perceived as different stages on a continuous health scale, based on their radiographic appearance. PC suggests that an individual's placement of a cut-off point for retreatment on the health continuum to a large extent is dependent on the agent's personal values. In the present study value judgements (utilities) concerning two periapical health states in endodontically treated teeth were investigated among 82 dental students. The two methods used to elicit utilities, a Visual Analogue Scale (VAS) and the Standard Gamble (SG), produced large inter- and intra-individual variations. VAS frequently generated lower utility values. The results obtained in the study satisfy a necessary criterion for the validity of PC and strengthen the position of the theory. [ABSTRACT FROM AUTHOR]

The large variations observed in dentists' management of periapical lesions in endodontically treated teeth suggest that disease concepts used in clinical practice should be investigated. In the present study it was hypothesized that dentists regard various periapical conditions as different stages on a health continuum. Variations could then be regarded as the result of the individuals selection of differing cut-off points for prescribing retreatment. The hypothesized decision-making model was tested using dental students in Amsterdam (Holland), Gothenburg (Sweden) and Pavia (Italy). The students were shown six simulated cases among which the quality of root filling seal and presence of post and crown were systematically varied. For each case, management of five periapical conditions was assessed. Five options were offered: no therapy, wait-and-see, nonsurgical retreatment, surgical retreatment, and extraction. For each examiner and case a `retreatment preference score (RN)' was established. The investigation showed large interindividual variations in RPS. A statistically significant higher mean RN was seen among students in Pavia compared with students in Amsterdam and Gothenburg. Among all observers and cases it was found that if retreatment was proposed for a certain size of lesion, retreatment was subsequently selected for all larger lesions. The experiment gave evidence in support of the proposed hypothesis. The data also suggest that the choice of retreatment criterion is affected by values, costs of retreatment and technical quality of the original treatment. [ABSTRACT FROM AUTHOR]

Aim To describe conventional and surgical endodontic treatment of a maxillary right lateral incisor with an unusual root dilaceration and to discuss the treatment outcome. Root dilacerations refer to severe curvature or angulations that may occur anywhere along the length of a root. This anatomical deviation may present an unfavourable outcome if clinicians fail to recognize the difficulties. The following case report describes conventional and surgical endodontic treatment of a maxillary right lateral incisor with an unusual root dilaceration. Key learning points •Root morphology may present a challenge for clinicians during root canal treatment. •Clinicians should be aware of the importance of surgical endodontics and be familiar with microsurgery principals and techniques. [ABSTRACT FROM AUTHOR]

AbstractAim The purpose of this study was to quantify the amount of remaining gutta-percha/sealer on the walls of root canals when two engine-driven instruments (Quantec and ProFile) and two hand instruments (K-file and Hedström file) were used to remove these materials. The amount of apically extruded debris and the time required for treatment were also recorded. Methodology One hundred extracted mandibular premolars were prepared using a modified step-back, flare technique and obturated with the lateral condensation technique. After repreparation with the test instruments, the specimens were cut transversally at the cervical, middle and apical thirds with steel discs and the three sections were split longitudinally. The amount of residual debris on the canal walls in each section was examined using a stereomicroscope. Results In all groups the cervical and middle thirds showed no debris. In the apical third, obturating material was observed in some specimens. No statistically significant difference was found between the two groups for incidence of debris, although the Hedström group showed a greater number of samples with remaining gutta-percha/sealer. When analysing dirty specimens only, there was a statistically significant difference between the four groups (P < 0.01) with the Hedström group having significantly less length of canal wall with remaining obturation material than the Quantec group. There was no significant difference amongst the groups for weight of extruded debris. However, there was a significant difference amongst the groups for mean treatment time with the Hedström file group requiring significantly less time than the Quantec group (P < 0.001); no significant differences were found between the other groups. Six instruments fractured in the Quantec group, four in the ProFile group, two in the Hedström group and two in the K-type group. Conclusions The results showed that overall, all instruments may leave filling... [ABSTRACT FROM AUTHOR]

Aim. The study aimed at evaluating the incidence of dentinal defects after root canal retreatment with ProTaper Universal retreatment (PTUR) and XP-endo Shaper and Finisher R (XP). Materials and Methods. Sixty extracted single-rooted human premolars were selected and divided into 4 groups of 15 teeth each. In the negative control group, the teeth were left unprepared. In the positive control group, the teeth were prepared with ProTaper Next and obturated with no further retreatment. In the PTUR and XP groups, the teeth were prepared and obturated followed by removal of the filling material at body temperature using PTUR and XP instruments, respectively. The roots were then sectioned at 3, 6, and 9 mm from the apex and observed under a digital microscope to detect defects. Results. PTUR group showed significantly higher (p value <0.05) incidence of defects than the other groups. Comparison of no defects versus defects between groups in different areas of root canals demonstrated significant difference among the groups in the apical and cervical regions. Conclusion. Within the limitations of the present study, PTUR files created significantly more dentinal defects than XP files, with most of those defects at the cervical and apical areas of the root canals. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to assess the effect of solvents on root canal transportation in endodontic retreatment. Sixty extracted human permanent mandibular first molars with curved root canals were selected. All of the root canals were prepared using Twisted File Adaptive instruments ( Sybron Endo, Orange, CA, USA) and filled with gutta-percha and AH Plus sealer ( Dentsply De Trey, Konstanz, Germany) using the cold lateral compaction technique. The teeth were assigned to four retreatment groups as follows ( n = 15): eucalyptol, chloroform, orange oil and control. The canals were scanned using cone-beam computed tomography scanning before and after instrumentation. The chloroform group showed a significantly higher mean transportation value than the orange oil and control groups at the 3 and 5 mm levels ( P = 0.011 and P = 0.003, respectively). There was no significant difference among the orange oil, eucalyptol and control groups in terms of canal transportation ( P > 0.61). The chloroform led to more canal transportation than the eucalyptol and orange oil during endodontic retreatment. [ABSTRACT FROM AUTHOR]

Large interindividual variations have been demonstrated when dentists suggest clinical management of endodontically treated teeth. Since variations also have been shown in radiographic diagnosis of the periapical tissues, a hypothesis was tested that explains variation in treatment as a function of variation in diagnosis. Fifty-four general practitioners suggested diagnosis and management of 32 endodontically treated roots. Spearman's rank correlation coefficient reached 0.298 when the examiners were definitely sure of the presence of a periapical lesion, and 0.356 when probable lesions also were included. Conclusively, the hypothesis seemed to have a limited value in explaining why dentists carry out retreatment. Instead a multi-aspect approach to this problem is suggested. [ABSTRACT FROM AUTHOR]

A 24-year-old female with no contributory medical history had been treated by orthodontic alignment and transplantation of the lower left first premolar to the upper left first premolar site to correct for congenitally missing upper premolars. Subsequently, the transplanted premolar was treated by conventional endodontics and apical surgery for persistent periapical periodontitis over a span of 12 years. A combination of conventional endodontic retreatment and periapical surgery resulted in periapical healing. This case outlines the need for careful preoperative case assessment. [ABSTRACT FROM AUTHOR]

The present study evaluated the effectiveness of two reciprocating systems for the removal of root-filling material during endodontic retreatment. One hundred extracted mandibular premolars were prepared and root-filled with gutta-percha and sealer. Root fillings were removed with K-files according to the following techniques: Group A – hand instrumentation; Group B – Endo-Gripper system driven by compressed air; Group C – INTRAmatic 29CH + INTRA-LUX 3LD driven by compressed air; Group D – Endo-Gripper system driven by electric engine; Group E – INTRAmatic 29CH + INTRA-LUX 3LD driven by electric engine. The amount of filling debris on root canal walls was assessed radiographically and analysed using Auto CAD 2000 software. One-wayanova and Duncan’s test revealed statistically significant differences only in the middle third ( P = 0.01); the best results being reached in group D. The apical third displayed the greatest amount of filling material debris, regardless of the technique used. [ABSTRACT FROM AUTHOR]

A rare case of a four-rooted maxillary second molar in a 39-year-old male patient is reported. After clinical and radiographic examination, two separate mesio-buccal roots were detected, and a treatment plan consisting treatment of the mesio-buccal roots and retreatment of the disto-buccal and palatal roots was made to resolve the previous treatment failure. The tooth was treated by orthograde endodontic retreatment in two visits. Mesio-buccal canals that were located in the separate mesio-buccal roots (which were missed in previous treatment) were found and treated. The case report underlines the importance of complete knowledge about root canal morphology and possible variations, coupled with full clinical and radiographic examination, in order to increase the ability of clinicians to treat difficult cases. [ABSTRACT FROM AUTHOR]

Aim: This study compared intracanal removal of filling as well as the frequency and volume of extruded material after retreatment with either HyFlex or Reciproc instruments in mandibular teeth from cadavers. Methodology: The root canals of 14 pairs of contralateral single‐rooted teeth in mandibles of cadavers were instrumented with Reciproc R40 and filled using lateral compaction. The mandibles were scanned in a micro‐computed tomographic (micro‐CT) device before and after retreatment procedures. The contralateral teeth were assigned to two groups (n = 14) according to the retreatment protocol using either HyFlex or Reciproc instrument systems. In the HyFlex group, the HyFlex Remover instrument was worked 3 mm short of the working length (WL), followed by HyFlex CM 40.04 and 50.04 at the WL. In the Reciproc group, the R50 instrument was worked up at the coronal two thirds, followed by two more cycles until the WL was reached. Pre‐ and post‐operative micro‐CT images were analysed for extrusion and intracanal removal of filling material. Results: After retreatment, extrusion of filling material occurred in 11 (78%) and 14 (100%) teeth from HyFlex and Reciproc groups respectively (p >.05). A similar volume of extruded material was observed after retreatment with both systems (p >.05). A significant decrease in the intracanal filling volume was verified after retreatment with both tested systems (p <.05). However, residual filling material was found in all root canals, regardless of the system. The amount of filling material removed (HyFlex = 80.8%; Reciproc = 65.9%) and the operation time was similar between systems (p >.05). Conclusions: A high frequency of filling material extrusion was observed after retreatment with the two systems in a cadaver model, with no significant difference between them. Both protocols obtained similar efficacy in filling material removal procedures, although none completely cleaned the canals. [ABSTRACT FROM AUTHOR]

A separated instrument complicated orthograde endodontic retreatment of a maxillary molar tooth with apical periodontitis. The tooth was treated utilizing microsurgical techniques that employed an operating microscope, ultrasonics, micro-instrumentation and mineral trioxide aggregate as a root-end filling material. Healing was evident at a 12-month review appointment. Microsurgical techniques have significantly improved the outcomes for healing of periapical lesions when compared to traditional approaches to endodontic surgery. Success rates have been shown to be comparable with conventional orthograde treatment. [ABSTRACT FROM AUTHOR]

This case reports on the treatment of an immature tooth initially treated with calcium hydroxide apexification techniques. When the patient subsequently sought treatment for aesthetic concerns, the presence of apical periodontitis required revision of the endodontic procedure. Resolution of the periapical radiolucency was evident at a 12-month review. The use of mineral trioxide aggregate as an apical filling material and restoration with chemically cured composite resin extending into the coronal third of the root may prevent further contamination of the root canal system and strengthen the tooth. [ABSTRACT FROM AUTHOR]

Post-treatment apical periodontitis may persist due to biological factors as outlined by Nair or when treatment procedures have been ineffective in eliminating the intraradicular infection. This case series reports on the management of five posterior teeth restored with posts where microsurgical techniques were employed utilising the operating microscope, ultrasonics, micro-instrumentation and mineral trioxide aggregate as a root-end filling material. Healing was evident at 12-month review appointments. Microsurgical techniques have significantly improved the outcomes for healing of periapical lesions when compared to traditional approaches to endodontic surgery. Success rates have been shown to be comparable with conventional orthograde treatment. [ABSTRACT FROM AUTHOR]

Inflammatory external root resorption is one of the major complications after traumatic dental injury. In this case report, we describe treatment of a maxillary central incisor affected by severe, perforating external root resorption. An 18-year-old patient presented with a previously traumatized, root-filled maxillary central incisor associated with pain and sinus tract. Radiographic examination revealed periradicular lesion involving pathologic resorption of the apical region of the root and lateral root surface both mesially and distally. After removal of the root canal filling, the tooth was disinfected with intracanal triple antibiotic paste for 2 weeks. The antibiotic dressing was then removed, and the entire root canal was filled with mineral trioxide aggregate. The endodontic access cavity was restored with composite resin. After 18months, significant osseous healing of the periradicular region and lateral periodontium had occurred with arrest of external root resorption, and no clinical symptoms were apparent. [ABSTRACT FROM AUTHOR]

Introduction: Patients' experiences related to dental treatment could influence care‐seeking behaviour and engender personal bias. Although endodontic retreatment and apical surgery are procedures often performed to manage previously treated teeth with persistent disease, there is lack of information regarding psycho‐social perspectives of patients who undergo these treatments. Our aim was to compare experiences of patients who received these two treatment modalities using a qualitative approach. Methods: A purposive sample of patients was taken from our previous study utilizing the Oral Health Impact Profile to compare oral health‐related quality of life of 150 patients who received retreatment and apical surgery. Patients who reported impact and no impact were invited to participate in focus group discussions (FGDs). Eighteen patients from the retreatment group and 15 patients from the surgical group participated in six FGDs. Thematic analysis was conducted to identify key themes. Results: Four themes emerged: (1) psycho‐social disability associated with dental procedures, (2) physical disability associated with dental problems, (3) reliance on dentist's advice for treatment and (4) self‐management to preserve treated teeth. Patients undergoing endodontic retreatment reported significant time loss from work and were less informed of alternative treatment options. However, they were pleased with the aesthetics of their teeth, especially if new crowns were made. Patients undergoing surgery experienced anxiety related to loss of control during surgery and apprehension on visualizing the wound post‐surgery. They reported more impact on their diet, social interaction and sleep quality and some felt self‐conscious due to post‐treatment gingival recession. Patients in both groups placed great trust in professional advice and expressed a clear desire to maintain their natural dentition. There was low awareness regarding long‐term care and future sequelae of their treated tooth. Conclusions: Patients reported different psycho‐social and physical impacts following endodontic retreatment and apical surgery. Patients undergoing endodontic retreatment were more satisfied with aesthetic outcomes but experienced greater impact related to complexities and length of time taken for treatment. Patients undergoing surgery were better informed of treatment options but experienced greater physical and psycho‐social disability during the recovery phase. Clinicians could consider incorporating findings from this study into the patient–dentist discussion. [ABSTRACT FROM AUTHOR]

Aim: To compare the effect of low‐level laser therapy (LLLT) on postoperative pain after single‐visit root canal retreatment on mandibular molars. Methodology: This randomized controlled clinical trial included 36 patients referred to the Department of Endodontics, Islamic Azad University, Tehran, Iran. Healthy patients who required root canal retreatment on symptomatic first or second mandibular molars, with a PAI index score of 2 or 3, preoperative tooth and percussion pain of <56 mm on a 170‐mm visual analogue scale (VAS) were included. After local anaesthesia using inferior alveolar nerve block followed by rubber dam isolation and access cavity preparation, the D RaCe retreatment system was used to remove the existing root filling material, and after canal negotiation and gaining patency, working length was determined with an apex locator. Further canal enlargement was carried out with size 35, 0.04 taper, and size 40, 0.04 taper RaCe rotary instruments and then canals were filled using laterally compacted gutta–percha points and AH Plus sealer. The patients were randomly assigned to treatment groups: In the LLLT group, a 980‐nm diode laser set at 6.89 W/cm2 energy density, 0.5 W power, and a tip diameter of 10 mm were activated from the buccal side on the mesial and distal root apices for 15 s. In the sham group, the laser handpiece was placed inside the patient's mouth at the same location, but the laser was not activated. Then patients were instructed to record their postoperative pain levels at 4, 8, 12 and 24 h and 2, 3 and 7 days after treatment on separate VAS scales. For data analysis, the independent sample t and the Mann–Whitney U tests were used. Nominal variables were analysed by using the chi‐square test. Results: In the LLLT group, the most intense pain was reported 24 and 48 h post‐treatment [mean (SD) = 0.22 (0.54) for both], whereas in the sham group, the most intense pain level was observed 4 h post‐treatment [mean (SD) = 0.78 (0.80)]. At the 4‐h interval, pain intensity was significantly lower in the LLLT group (p =.016). Conclusions: Low‐level laser therapy reduced postoperative pain after single‐visit root canal retreatment of mandibular molars only four hours following the procedure. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Chloroform is among the most common solvents for root canal treatment. Despite its classification as a potential carcinogen, it is effective if used correctly. Inappropriate use can lead to severe complications, including persistent pain, gingival recession, and necessitating surgical intervention to resect necrotizing bone. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the complexity of root canal treatments accepted for treatment by postgraduate training grades at Cardiff University Dental Hospital (CUDH) using the English Commissioning Standard for Restorative Dentistry (ECS) in comparison with the American Association of Endodontists case complexity form (AAE) and the Restorative Index of Treatment Need (RIOTN). Methodology: Two hundred case records were evaluated using the AAE, RIOTN and ECS scoring systems. Each case received a score from minimal to high complexity (1–3). Examiners were calibrated and inter‐examiner reliability calculated using the percentage agreement. Frequency of scores were then compared. Results: Most cases were at level 3 and assessment varied amongst the criteria used (AAE: 99.5%, RIOTN: 65.5% and ECS: 55.5%). The AAE factor 'endodontic treatment history' was largely responsible for differing scores when compared with the RIOTN (78%) and ECS (64%). The RIOTN factor regarding post treatment disease ('endodontic retreatment') was responsible for increased complexity compared with ECS in most cases (74%). The ECS factor 'quality of root filling' was the most common reason (85%) for an increase in complexity compared with RIOTN. Conclusions: Within the limitations of this service evaluation, it was possible to conclude that a high proportion of cases treated by training grades at CUDH were of a high complexity level (level 3) using the three guidelines (ECS, AAE and RIOTN). These cases were appropriate for postgraduate training under various levels of supervision and substantiated by the findings reported here. The factors responsible for a large part of difference in allocation of scores amongst the systems were 'endodontic treatment history', 'root canal retreatment' and 'quality of root filling'. [ABSTRACT FROM AUTHOR]

Introduction: Treatment decisions for a heavily restored endodontically treated tooth vary amongst clinicians owing to multitude of factors. This phenomenon not only often poses dilemmas to clinicians of different clinical backgrounds, but also exerts a degree of treatment difficulty to the treating clinician. Previous studies indicated that specialty training and clinical experience significantly impacted clinical decision‐making process. Materials and methods: Master of Science postgraduate students in endodontics, prosthodontics, periodontics, oral surgery and implantology participated in a questionnaire‐based cross‐sectional study. The dental specialties were further categorised into restorative and surgical dentistry. A multiple‐choice questionnaire with three clinical cases was distributed to the students. Data were analysed for trends using descriptive statistics. Results: There was a 44% response rate; the majority of respondents were from restorative dentistry specialties. Cases 1 and 2 were rated as moderate to high difficulty, and Case 3 was predominantly rated as high difficulty with procedure predictability being the main factor affecting their clinical decision‐making in three cases. Endodontic retreatment was selected as the preferred treatment in Cases 1 and 2 and periradicular surgery in Case 3. The students were fairly confident in managing Cases 1 and 2, but not in Case 3. Referral patterns were consistent in Cases 1 and 2 with endodontists being the first choice of referral except for Case 3 where 48% preferred to refer to oral surgeons and 35% choosing endodontists. Some indication of differences between specialties were noted throughout. Years in practice appeared to be related to the importance of predictability in Case 3 only. Conclusion: Considerable inter‐clinician variability was noted whereby specialty postgraduate training impacted on clinical decision‐making. Overall, procedural predictability, technical difficulty, risk of damage to the tooth and patient preference were the most highly ranked factors affecting clinical decision‐making. Evidence‐based treatment guidelines and dental curricula should be reviewed to enhance inter‐clinician agreement in clinical decision‐making, ultimately improving patient care. [ABSTRACT FROM AUTHOR]

Aim: To investigate what happens to cross‐sectionally identified root‐filled teeth over a 6‐year period, regardless of the time that elapsed since primary root canal treatment, in a cohort of adult patients regularly attending a Public Dental Service. A secondary aim was to investigate how the cumulative events affecting root‐filled teeth over the same time were associated with variables obtained from a baseline examination. Methodology: Adult patients with ≥1 previously root‐filled tooth and regularly attending the Public Dental Service in Örebro County were enrolled for study participation in 2015. General dental practitioners examined all identified root‐filled teeth in this cohort at baseline using a standardized protocol and were also responsible for further decision‐making and treatments. After six years, information on events of the root‐filled teeth was collected from dental records. The highest rating (most invasive treatment) on a 5‐point ordinal scale was used in the analyses. Regression analyses with stepwise selection were performed for associations between patient‐ and tooth‐related factors and events. Results: A total of 445 patients with 1007 root‐filled teeth were followed the entire observation time. Twenty (2.0%) of the root‐filled teeth had endodontic retreatment and 150 (14.9%) were extracted over six years. Among teeth with periapical radiolucency or pain, the majority did not undergo retreatment or extraction; however, the multivariate analysis demonstrated that retreatment or extraction was associated with baseline recordings of teeth with periapical radiolucency (p <.0001), tenderness to percussion (p <.0001), and poor coronal restoration (p <.0001). Conclusions: This study corroborates the notion that in general dentistry, root‐filled teeth with radiological signs of apical disease often remain untreated over time. Furthermore, it also reveals that root‐filled teeth presenting with mild pain do not necessarily receive any intervention. However, teeth with baseline signs of apical periodontitis, pain, or inadequate coronal restoration were more likely to have received intervention during the six‐year period. [ABSTRACT FROM AUTHOR]

Removing a fiber post from a root canal that requires endodontic retreatment is often very challenging. Conventional freehand techniques for removing fiber posts are time-consuming, sometimes result in iatrogenic errors, and heavily rely on the practitioner's experience. The endodontic static guide can be an alternative method. While the use of an endodontic 3D-printed static guide for fiber post removal has been reported as highly successful, it can also cause complications. Skipping any critical steps during the guide construction or its clinical application can lead to errors. This case report presents the saving of a compromised tooth with a fractured fiber post and a periapical lesion around the apex through the use of an endodontic static guide for fiber post removal. This study describes possible sources of error that may happen during construction and clinical use of the guide. [ABSTRACT FROM AUTHOR]

Aim: To compare the removal of root fillings in extracted teeth using the ProTaper Universal Retreatment system (PTUR) followed by a supplementary preparation with the XP‐Endo Finisher file. Methodology: The mesiobuccal root canals of 30 extracted mandibular first molars were instrumented with ProTaper Universal NiTi files up to F2 and filled with one of the following sealers using a single‐cone technique (n = 10): AH Plus, NeoMTA Plus and EndoSequence BC. The root fillings were removed using the PTUR system with additional apical preparation using ProTaper F2 and F3 files. Then, an additional preparation with an XP‐Endo Finisher file was performed. The samples were scanned using micro‐CT before and after retreatment and again after the use of the XP‐Endo Finisher to assess the volume of remaining filling material. Data were analysed by Kruskal–Wallis and Friedman's two‐way analysis of variance tests with Bonferroni correction. Results: No significant difference in the initial filling volume was observed amongst the groups (P > 0.05). The amount of filling materials in each group decreased significantly after retreatment with rotary files (P < 0.05). After initial retreatment, the volume of the remaining filling amongst the groups was similar (P > 0.05). Additional preparation with the XP‐Endo Finisher improved the removal of filling materials regardless of the sealer type (P < 0.05). Conclusions: In the mesiobuccal root canals of extracted mandibular first molars, additional preparation using an XP‐Endo Finisher file, after using the PTUR system and F3 ProTaper instruments, enhanced the removal of filling materials from root canals. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effectiveness of a solvent (eucalyptol) in improving filling material removal from canals connected by isthmuses, and the additional cleaning effect of a finishing instrument. Methodology: The mesial canals from 32 mandibular molars (Vertucci's type II morphology) were instrumented and filled with the single‐cone technique using Reciproc R25 gutta‐percha points (VDW, Munich, Germany) combined with Sealer 26 (Dentsply, Petrópolis, RJ, Brazil). Each root was then subjected to retreatment using the Mtwo instrument system (VDW), with or without a solvent (n = 16 per group). The volume of filling material in the canals was assessed by micro‐computed tomographic (micro‐CT) scans taken before and after retreatment. Canals with remnants of filling material received a supplementary procedure with the XP‐endo Finisher R instrument (FKG Dentaire, La Chaux‐de‐Fonds, Switzerland), with or without eucalyptol, and another micro‐CT scan was taken. All retreatment procedures were performed inside a cabinet under a controlled temperature (37 °C). Filling material removal was evaluated in the 5‐mm apical canal system for the canal+isthmus space or the isthmus alone. Statistical analyses were performed to compare the removal of filling material with and without eucalyptol, and after a supplementary approach with XP‐endo Finisher R. The level of significance was set at 5% for all statistical tests (P < 0.05). Results: The amount of filling material removed from the canal+isthmus with Mtwo instruments was 83.2% when no solvent was used and 83.8% using the solvent (P > 0.05). When the isthmus area was evaluated separately, most specimens were associated with a reduction in the filling material, with no significant difference between the groups with or without using a solvent (P > 0.05). The supplementary step with XP‐endo Finisher R significantly improved removal of filling material from both canal and isthmus area (P < 0.05), regardless of the use of a solvent (P > 0.05). Conclusion: The use of eucalyptol did not improve filling material removal from Vertucci's type II molar mesial canals and isthmuses. XP‐endo Finisher R significantly enhanced removal of filling material from the canals and isthmuses. [ABSTRACT FROM AUTHOR]

Aim To evaluate the volume of remaining filling material in the mesial root canals of mandibular molars after root canal retreatment with different procedures performed sequentially. Methodology The mesial root canals of 12 human first mandibular molars were instrumented using the BioRace system until a size 25, .06 taper instrument. The mesial roots were filled with gutta-percha and AH-Plus using a vertical compaction technique. The specimens were scanned using microcomputed tomography with a voxel size of 16.8 μm before and after the retreatment procedures. To remove the filling material, the root canals were enlarged until the size 40, .04 taper instrument. The second step was to irrigate the root canals with xylene in the attempt to clean the root canals with paper points. In the third step, the passive ultrasonic irrigation technique (PUI) was performed using 2.5% sodium hypochlorite. The initial and residual filling material volume (mm3) after each step was evaluated from the 0.5 to 6.5 mm level. The obtained data were expressed in terms of percentage of residual filling material. Statistical analysis was performed using the Friedman test (P < 0.05). Results All specimens had residual filling materials after all retreatment procedures. Passive ultrasonic irrigation enhanced the elimination of residual filling material in comparison with the mechanical stage at the 0.5-2.5 mm and 4.5-6.5 mm levels (P < 0.05). No significant difference was found between xylene and PUI methods. Conclusions Filling materials were not completely removed by any of the retreatment procedures. The use of xylene and PUI after mechanical instrumentation enhanced removal of materials during endodontic retreatment of anatomically complex teeth. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate whether retreatment of root fillings was judged necessary or not and. which kind of retreatment was preferred among a group of general dental practitioners in Germany. A questionnaire comprising 19 cases of endodontically treated teeth with different case histories and several treatment options was sent to all general practitioners in Göttingen (Germany). The cases included teeth with periapical radiolucencies, pain, apical resorption, under- and overfilling, and unfilled root canals. Results obtained from 43 questionnaires returned indicate that non-intervention or further radiographic monitoring were preferred by the majority of general practitioners in 110 of 19 cases, even in the presence of periapical pathosis. Only five cases; were judged to require conservative endodontic retreatment and, in four cases, root resection. The results revealed large inter- and intra- individual discrepancies in the estimation of endodontic retreatment need. [ABSTRACT FROM AUTHOR]

Healthcare is an expensive endeavour, and it is likely that costs for endodontic treatment will grow over the next decade. The assessment of costs and, in most cases, health outcomes, and the comparison of the cost‐health ratio of interventions, is at the heart of health economics. The present review aims to introduce the main concepts of health economic analysis, to systematically review the existing economic endodontic literature, and to deduce further action for the community. Overall, the identified body of evidence on the health economics of endodontic therapies is heterogenous and has several limitations: Not all studies identified robust data to inform their analyses and many relied on a wide range of assumptions, which were only explored for their impact in a limited way. However, a number of themes were identified from the review: (1) Maintaining pulpal vitality is preferable over root canal treatment if possible when it comes to cost‐effectiveness. (2) Retaining teeth is usually more cost‐effective than removing and replacing them. (3) Endodontic retreatment may be clinically indicated, but not always cost‐effective, and should hence be considered carefully. In conclusion, the general sparsity of economic analyses is a concern, as decision makers such as commissioners or those funding dental care increasingly rely on them. The endodontic community is called to action to improve the competency of both researchers to conduct such analyses and consider them when planning research, but also clinicians who should factor in health economics when assigning interventions. Health economics should become an accepted pillar of endodontic research. [ABSTRACT FROM AUTHOR]

ABSTRACT The aim of the study was to assess the penetrability of two endodontic sealers (AH Plus and MTA Fillapex) into dentinal tubules, submitted to endodontic treatment and subsequently to endodontic retreatment. Thirty ex vivo incisors were prepared using ProTaper rotary system up to F3 instrument and divided in three groups according to the endodontic sealer used for root canal filling: AH Plus (AHP), MTA Fillapex (MTAF), and control group (CG) without using EDTA previously to the root canal filling. Rhodamine B dye (red) was incorporated to the sealers in order to provide the fluorescence which will enable confocal laser scanning microscopy (CLSM) assessment. All specimens were filled with gutta-percha cones using the lateral compaction technique. The specimens were submitted to endodontic retreatment using ProTaper Retreatment system, re-prepared up to F5 instruments and filled with gutta-percha cones and the same sealer used during endodontic retreatment. Fluorescein dye (green) was incorporated to the sealer in order to distinguish from the first filling. The roots were sectioned 2 mm from the apex and assessed by CLSM. No difference was found between the two experimental groups ( P > 0.05). On the other hand, in the control group the sealers were not capable to penetrate into dentinal tubules after endodontic treatment ( P > 0.05). In retreatment cases, none of the sealers were able to penetrate into dentin tubules. It can be concluded that sealer penetrability is high during endodontic treatment. However, MTA Fillapex and AH Plus do not penetrate into dentinal tubules after endodontic retreatment. Microsc. Res. Tech. 77:467-471, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Aim To evaluate the efficacy of filling material removal from oval-shaped canals after the use of supplementary files (XP-endo Finisher and XP-endo Finisher R) through microcomputed tomographic (micro-CT) analysis. Methodology The root canals of twenty maxillary single-rooted teeth were prepared with Reciproc R25 files and filled with gutta-percha and AH Plus sealer using the continuous wave of condensation technique. The root canals were then retreated using Reciproc R25 and R40 instruments. After this, the specimens were assigned to two groups according to the supplementary cleaning approach, using XP-endo Finisher and XP-endo Finisher R. The surface area and volume of removed filling material was assessed using micro-CT imaging before and after the use of the XP-endo instruments. Data were analysed statistically with a significance level of 5%. Results Removal of filling material at 66.8% and 59.4% in volume and 67.3% and 61.4% in surface area was seen for the XP-endo Finisher and the XP-endo Finisher R files, respectively. The amount of filling material removed by both supplementary files was highly significant ( P = 0.000). No significant difference in the percentage of removed filling material was detected for the XP-endo instruments ( P = 0.636 for volume and P = 0.667 for surface area). Conclusions Both XP-endo files were equally effective in the removal of remaining filling material from straight oval-shaped canals. None of the instruments were able to remove all the residual filling material. [ABSTRACT FROM AUTHOR]

Aim To compare the effectiveness of large apical preparations and complementary canal preparation with the Self-Adjusting File (SAF) in removing endotoxins from the root canal of teeth with apical periodontitis. Methodology Ten single-rooted and single-canaled teeth with post-treatment apical periodontitis were selected. Endotoxin samples were taken after removal of the root filling (S1), after chemomechanical preparation (CMP) using 2.5% NaOCl and an R25 file (S2), after CMP using 2.5% NaOCl and an R40 file (S3) and after complementary CMP using the SAF system (S4). Limulus amebocyte lysate (LAL) was used to measure endotoxin levels. The Friedman and Wilcoxon tests were used to compare endotoxin levels at each clinical intervention (P < 0.05). Results After root filling removal, endotoxin was detected in 100% of the root canals (S1, 4.84 EU mL−1). CMP with the R25 file was able to significantly reduce endotoxin levels (P < 0.05). Increased levels of endotoxin removal were achieved by apical preparation with the R40 file (P < 0.05). Complementary CMP with SAF did not significantly reduce endotoxin levels (P > 0.05) following the use of the R40 instrument. Conclusions Apical enlargement protocols were effective in significantly reducing endotoxin levels. Complementary preparation with the SAF system failed to eliminate residual endotoxin contents beyond those obtained with the R40 instrument. [ABSTRACT FROM AUTHOR]

Aim Part 2 of this prospective clinical study aimed to compare the 1-year outcome of root canal retreatments, when individual roots and teeth were assessed by periapical radiographs and cone beam computed tomography (CBCT). Methodology Subjects participating in this study had been referred for management of an endodontic problem associated with one or more root filled teeth. Root canal retreatment was performed by Specialists or postgraduate students under the direct supervision of Specialist endodontic staff. A total of 98 teeth (84 patients) were reassessed clinically and radiographically 1 year after completion of root canal retreatment. The postoperative periapical radiographs and CBCT scans were compared with their respective pre-treatment (diagnostic) periapical radiographs and CBCT scans. The increase or decrease in size of existing periapical radiolucencies and development of new radiolucencies were assessed by a consensus panel consisting of two calibrated examiners. They also determined an appropriate management plan for each case based on the radiographical findings. Comparison of the outcome diagnosis of individual roots and teeth and case management, when assessed by periapical radiographs and CBCT scans, was performed using chi-squared and McNemar's tests. Results An overall favourable result of 93% success for teeth (96% roots) was recorded when the assessment was undertaken by periapicals compared with 77% success for teeth (87% roots) when assessed by CBCT. A significant difference in outcome diagnosis of single paired roots ( P < 0.0001) and teeth ( P = 0.0001) was observed when comparing periapicals to CBCT for the cohort of teeth as a whole. When comparing the future management plan on the basis of radiographic information alone, there was a significant difference between periapicals and CBCT-based management ( P = 0.01). Conclusion Diagnosis using CBCT revealed a significantly lower number of favourable outcomes than periapicals in root canal retreatment. This significantly affected the future management of cases attending for a review. [ABSTRACT FROM AUTHOR]

The purpose of this article was to report a case of untreated apical periodontitis resulting in severe late complications. A patient with an asymptomatic crowned root canal‐treated mandibular molar revealing a radiographic substandard endodontic treatment and a slight periapical radiolucency was made aware of the treatment options and opted for no treatment. The lesion slightly increased in size after 6 years, but the tooth remained asymptomatic and endodontic retreatment was again refused. After 4 more years, the patient presented with an abscess and severe pain, complicated by paraesthesia of the left chin and lip. Radiographic examination revealed that the lesion had increased considerably to involve the mandibular canal. The treatment protocol included long‐term intracanal medication with calcium hydroxide and follow‐ups revealed complete resolution of the periapical radiolucency and the paraesthesia had completely subsided. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The prevalence of vertical root fractures (VRF) ranges from 2% to 20%, and is associated with endodontically‐treated teeth (ETT). The aim of the present study was to analyze clinically and radiographically, at different intervals of time, some of the risk factors present in ETT that developed VRF. Methods: A classification model according to time measured the follow‐up period of three groups. A match was made for times of occurrence (cases) and follow up (controls). An odds ratio (OR) test and a logistic regression model set at 95% confidence interval (CI) established the VRF probability when different clinical factors (patient, tooth, and endodontic or restorative treatment) were present. Results: The sample was composed of 197 ETT (41 cases and 156 controls). A classification model set the trend, thus defining three groups: group 1 (1‐4 years of follow up): endodontic retreatment (OR: 8.01, 95% CI: 1.85‐37.90, P=.0014), indirect restoration (OR: .202, 95% CI: .036‐.979, P=.05); group 2 (5‐8 years of follow up): primary treatment (OR: .052, 95% CI: .002‐.680, P=.044) and the ‘single tooth’ category (OR: .042, 95% CI: .002‐.453, P=.02) demonstrated a significant association with VRF; and group 3 (>9 years of follow up): no association. Conclusion: Endodontic retreatment had the highest risk association for VRF after 1‐8 years of follow up. Indirect and individual restorations were not significantly associated with VRF. [ABSTRACT FROM AUTHOR]

The present study aims to assess the efficacy of different irrigation agitation systems in removing calcium silicate‐based sealers from artificial standardised apical grooves. After the root canal instrumentation of 96 teeth, artificial apical grooves were created in half of each root. The samples were divided into two main groups according to the sealer type (AH Plus Jet [APJ] and Sure‐Seal Root™ [SSR]) (n = 48). The root halves were then reassembled and divided into four experimental groups based on the final irrigation technique used: Conventional Syringe Irrigation (CSI), Ultrasonic Irrigant Agitation (UIA), Sonic Agitation (SA) and Manual Dynamic Agitation (MDA). The roots were then dissembled to assess the amount of root canal sealer. UIA significantly removed more of SSR sealer than CSI, MDA and SA while there was no statistical difference between CSI, MDA, SA and UIA groups in the APJ group. None of the irrigation agitation systems used had completely removed the APJ and SSR sealers. However, UIA was more effective in removing SSR sealer from the standardised apical groove than were CSI, MDA and SA. [ABSTRACT FROM AUTHOR]

This study was to determine the effectiveness of diode laser (LI) and ultrasonic (UI)‐activated irrigation with or without a surfactant as adjunct techniques during the retreatment of gutta‐percha and tricalcium silicate‐based sealer (BC) sealer. Forty‐two single‐rooted premolars were instrumented and filled with gutta‐percha and BC sealer, then retreated using NiTi retreatment rotary files. Teeth were randomly divided into three equal groups: Control (manual irrigation), UI and LI groups. Each group was subdivided into 2.5% NaOCl irrigant and ChlorCid™️ Surf subgroups. The amount of material removed following UI and LI was significantly greater than that of manual irrigation (p < 0.0001). However, there was no significant difference between the surfactant subgroups, irrespective of irrigation technique (p = 1.00, p = 0.535, p = 0.805). The use of UI and LI adjuncts to NiTi rotary retreatment techniques showed significant improvement in gutta‐percha with BC sealer removal. However, surfactants had no effect on the efficacy. [ABSTRACT FROM AUTHOR]

Aim To evaluate the diffusion of hydroxyl ions from calcium hydroxide paste ( CH) before root canal filling and after retreatment. Methodology After preparation of 60 root canals, the cementum layer was removed, and the canals and root surfaces were treated for smear layer removal. The apical third of roots was covered with adhesive. The canals were filled with CH, and the teeth were placed in individual vials containing 10 mL of distilled water, which had its pH measured after 7, 14, 21 and 28 days (pH1). The root canals were then divided into five groups and filled with Resilon/Real Seal (G1) or gutta-percha and Endofill (G2), Sealapex (G3), AH Plus (G4) or MTA Fillapex (G5) sealers. After storage for 7 days, the root canals were retreated. The CH was again inserted into the canals, and the teeth were placed in new vials containing 10 mL of distilled water. The pH was again measured at 7, 14, 21 and 28 days (pH2). The initial and final pH readings (pH1 and pH2) were compared by anova, anova2 and Tukey's tests ( P < 0.05). Results The pH1 and pH2 measurements increased with time. The measurements obtained after retreatment were significantly higher than those obtained before root canal filling. Conclusions Hydroxyl ions are able to diffuse through dentinal tubules. Regardless of the filling material, it was possible to re-establish the permeability of dentine to ionic diffusion after retreatment. Time had a positive influence on ionic diffusion. [ABSTRACT FROM AUTHOR]

Mollo A, Botti G, Prinicipi Goldoni N, Randellini E, Paragliola R, Chazine M, Ounsi HF, Grandini S. Efficacy of two Ni-Ti systems and hand files for removing gutta-percha from root canals. International Endodontic Journal, 45, 1-6, 2012. Abstract Aim To compare the effectiveness of two Ni-Ti systems and hand files for removing gutta-percha and sealer from root canals. Methodology The root canals of 60 single-rooted human teeth were prepared, filled with gutta-percha and sealer (Pulp Canal Sealer; SybronEndo, Orange, CA, USA). Specimens were then divided into three groups ( n = 20), and root filling material was removed using MTwo Retreatment Files (group 1); R-Endo (group 2); K-files and Gates-Glidden drills (group 3). After retreatment, the efficacy of each technique was assessed using radiographs that were later digitized and the images analysed using AutoCAD 2004. The percentage of residual gutta-percha was calculated for the whole canal as well as for the coronal, middle and apical thirds. Time required, apically extruded debris and the number of fractured instruments were also recorded. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U-tests. Results All instrumentation techniques left gutta-percha and sealer remnants inside the root canals. Ni-Ti systems were significantly faster ( P < 0.05) than the manual technique and significantly more effective ( P < 0.05) in removing gutta-percha particularly from the middle and apical thirds of the root canal. R-Endo instrumentation was significantly more effective ( P < 0.05) than MTwo retreatment files in removing gutta-percha from the middle and apical thirds. R-Endo instruments were associated with the least number of cases of apical extrusion. One MTwo instrument fractured. Conclusions The Ni-Ti systems were more effective and faster than hand files, although all techniques left gutta-percha and sealer remnants on the root canals. [ABSTRACT FROM AUTHOR]