Nonsurgical Root Canal Retreatment Research Articles

A 12-month randomized controlled trial to assess the efficacy of revitalization of retreated mature incisors with periapical radiolucency in adolescents

The use of regenrative endodontics is restoring the health status of the root canals of retreated mature teeth is a novel approach. Therefore, the current trial aimed to compare the effectiveness of regenerative endodontic procedures (REPs) to non-surgical root canal retreatment (NS-RCR) in reducing periapical radiolucency over one year for the retreatment of mature incisors with periapical periodontitis. The secondary purpose was to assess clinical success and regain pulp sensibility. A parallel randomized controlled trial, 66 mature incisors with periapical radiolucencies were randomly divided into two equal groups and retreated with either REPs or NS-RCR. At baseline and after 6 and 12 months, teeth were assessed clinically and radiographically using a periapical index (PAI). The Mann–Whitney test was used to analyze nonparametric PAI scores. The Electric pulp test readings were analyzed using the repeated measure analysis of variance (ANOVA). Over the follow-up intervals, there was no significant intergroup difference in the PAI medians, the majority of the teeth displayed a reduction in periapical radiolucency. At the end of the follow-up period, the clinical successes for the REP and NS-RCR groups were 93.9% and 97%, respectively (p = 0.555). Positive pulp sensibility was recorded in 54.54% of cases in the REPs after 12 months. Both approaches showed a comparable diminishing of periapical radiolucencies and equivalent clinical results. A conventional, non-surgical endodontic retreatment may not always be necessary.

Root canal re-treatment with gutta percha - which techniques influence success?

A systematic review and meta-analysis of the literature was carried out assessing the success rate of root canal retreatment using gutta percha. Four of the largest databases were used to identify existing literature with no date or language restrictions. PubMed, Cochrane, ScienceDirect, Scopus and other additional sources were searched. Grey literature was also reviewed. Two authors, with Master's degrees in endodontics and with extensive university teaching experience, were selected to screen the databases to identify suitable studies. In case the authors were not able to agree during the study selection process, a third investigator was consulted. Specific inclusion and exclusion criteria were outlined and adhered to in the study selection. Two randomised controlled trials, seven single arm prospective studies and one single arm ambispective study published before the 10th of December 2022 were included. These studies evaluated the success of root canal re-treatment, obturated with gutta percha with at least a 1-year follow-up. Nine of the studies were published between 1998 and 2022. Seven studies were conducted in Europe, one in North America and one in Asia. Standard Cochrane methods to assess interval validity were used. Risk of bias in individual studies was assessed using The Newcastle-Ottawa quality assessment scale (NOS) for single-arm studies, and the Cochrane risk of bias tool (RoB2) was used for randomised controlled trials. Outcome measures were standardised as either success or failure of root canal retreatment. Success was classified into 2 different criteria: Strict criteria= absence of clinical signs and symptoms and radiographically normal periodontal ligament space; and Loose criteria= absence of clinical signs and symptoms and absence or reduction of apical radiolucency in the control radiograph. Statistical analysis was undertaken using R software and the Freeman-Turkey transformation was performed. Results were visualised using forest plots. Heterogeneity between studies was measured using the Cochrane Q test and I2 values. Whilst following strict criteria, the success rate of non-surgical root canal retreatment obturated with gutta percha was 71% for 1-3 years follow-up (95% CI, 0.66-0.77) and 77% for 4-5 years follow-up (95% CI, 0.67-0.86). Heterogeneity was moderate (I2 = 61.4) and low (I2 = 0.0), respectively. Factors reducing the success rate of root canal re-retreatment under the strict criteria were older patients, mandibular teeth, molar teeth, the presence of a peri-apical radiolucency, teeth with a previous radiolucency, large peri-apical radiolucency's, higher initial periapical index scores and multiple visit-retreatments. Following the loose criteria, the success rate of non-surgical root canal re-treatment obturated with gutta percha was 87% for 1-3 years follow-up (95% CI, 0.79-0.93) with significant heterogeneity across the studies (I2 = 88.5%). Factors influencing the success rate under the loose criteria were large periapical lesions >5 mm and higher initial periapical index (PAI) scores. Non-surgical root canal retreatment results in favourable outcomes. However, there are several factors which can result in a lower success rate: the presence and size of a periapical radiolucency, a higher initial PAI score, multiple-visit retreatments, and the size and position of the tooth.

Influence of operator’s experience on complications of root canal treatment using contemporary techniques: a retrospective study

BackgroundEndodontic treatment has benefited from the development of new techniques and equipment. Few clinical studies have been published on the complications associated with root canal preparations performed by doctors with different working experiences using contemporary techniques. This study aimed to analyze the complications of endodontic treatment performed by residents and endodontic specialists in a teaching stomatology hospital using contemporary techniques.MethodsCases of root canal treatment (RCT) and non-surgical root canal retreatment (ReRCT) performed by residents with 1–3 years of experience and endodontic specialists with 5–7 years of experience were collected from the electronic medical system of the Department of Endodontics, Beijing Stomatology Hospital, from September 1, 2020 to August 31, 2021. The cases were examined in terms of patient age, sex, type of tooth, diagnosis, treatment modality (RCT or ReRCT), number of appointments, whether an operating microscope was used, presence of ledges, canal transportation, perforations, missed canals, separated instruments, flare-ups and clinical incidence of second mesiobuccal (MB2) root canal in the maxillary molars.ResultsIn total, 859 teeth from 820 patients were included in the analysis. The overall incidence of complications in the resident group was significantly higher than that in the specialist group. More ledges and flare-ups were observed in the resident group (p < 0.05). The clinical incidence of MB2 was significantly higher in the specialist group (p < 0.05). There were no significant differences in root canal transportation, perforation, or instrument separation between the two groups (p < 0.05). Multivariate analysis showed that the incidence of root canal preparation complications was related to operator experience, tooth type and treatment modality.ConclusionsTechnical advancements could reduce the effect of working experience on RCT complications between residents and endodontic specialists in a teaching stomatology hospital.

Successful endodontic treatment reduces serum levels of cardiovascular disease risk biomarkers-high-sensitivity C-reactive protein, asymmetric dimethylarginine, and matrix metalloprotease-2.

To investigate serum biomarkers of inflammation 2 years following non-surgical root canal re-treatment (Re-RCT) and peri-apical surgery (PS). The results were correlated with signs and symptoms, treatment outcome, metabolic syndrome factors, infection with severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 (COVID-19) infection and COVID-19 vaccination. Subjects from our previous study were recalled for 2 years post-treatment follow-up. Changes to the patient's history (medical, dental, social) were noted. Periapical health of the treated teeth was examined both clinically and radiographically. Blood pressure, fasting HbA1C and low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides and total cholesterol (TC) levels were measured. Serum inflammatory marker levels were assayed using a Bio-Rad Bio-Plex 200 analyser and values at different time points within the same group were compared using a Wilcoxon signed-rank test and differences between groups with a Mann-Whitney test. Linear associations were tested using Pearson's correlations. The recall percentage at 2 years was 56.9% (n = 37), with a 100% radiographic success rate using periapical radiographs. In total, 21 cases (56.8%) were completely healed, and 16 cases (43.2%) were healing. Higher matrix metalloprotease 2 (MMP2) levels were present in the healing group compared to the healed group. Serum levels of high-sensitivity C-reactive protein (hs-CRP), asymmetric dimethylarginine (ADMA) and MMP-2 were significantly reduced (p ≤ .001) whereas other biomarkers showed significant increases at 2 year compared to pre-operative levels, while FGF-23 and ICAM-1 were not significantly increased. HbA1C (p = .015), TC (p = .003), LDL (p = .003) and HDL (p = .003) reduced significantly at 2 years post-treatment compared to their preoperative levels. COVID infection showed a significant association with MMP-9 (p = .048). hs-CRP, ADMA and MMP-2 can be regarded as prognostic biomarkers of successful Re-RCT and PS as they reduced at 2 year recall in cases which showed evidence of clinical and radiographic success. The successful treatment of chronic apical periodontitis is correlated with improvements in metabolic syndrome indicators, better glycemic control, and reduction at 2 year of some systemic inflammatory markers which are related to risks of cardiovascular disease events.

Management of Silver Point Retrieval for Root canal Retreatment: A Case Report

The historical importance of the solid core material is decreasing. When greater, more precise preparation of the canal space was not possible due to inferior metallurgy and instrument design, it was frequently utilized in the past. Silver points were machined with a circular cross section and more frequently than not went into oval than round canals. Long-term success rates might not be as great, but some cases may defy the odds. The prognosis after treatment and follow up by phone five years after the completion of treatment. A 46-years-old Chinese female was referred from a general private practitioner for the endodontic management of 36. The tooth had been endodontically treated 30 years before; subsequently the patient complained of occasionally mild discomfort that last a few second without any stimulating factors at the lower left molar. Radiographic finding revealed that the tooth had been treated with silver points and associated with periapical radiolucency. Non-surgical root canal retreatment was performed for the tooth. Conclusions: Due to the nature of partially removal silver points, even though the prognosis is guarded at the time of obturation. After five years, it was considered favourable although it was extracted due to fracture.

Endodontic retreatment of mandibular molars with the presence of missed middle mesial root canals: An important clinical lesion

Aim: Untreated root canals may have a direct impact on root canal treatment (RCT) outcome. The aim of this case report is to describe the nonsurgical root canal retreatment of two mandibular first molars in a patient's mesial roots that had previously missed middle mesial root canals (MMC). Methodology: A 14-year-old female was referred to the our clinic with the complaint of pain in the posterior areas of the right and left mandibula. During the examination, previous RCTs [teeth 36 (mandibular left first molar) and 46 (mandibular right first molar)] were observed. Besides, these teeth have periradicular lesions in the mesial roots probably due to unsuccessful previous treatment. Nonsurgical retreatment was suggested and accepted. Access cavities were prepared and the unnoticed MMCs were detected at the isthmus connecting both mesiobuccal and mesiolingual canals. All the root canals were shaped with NiTi rotary endodontic files. During the shaping, the root canals were irrigated copiously with NaOCl, EDTA, clorhexidine, and saline solutions under a certain protocol. Calcium hydroxide was used for intracanal dressing. Gutta-percha and a resin-based root canal sealer were used for filling. Coronal restorations of the teeth were completed with a composite resin. Conclusion: At follow-up examinations after 3-, 6-, and 12-months, the teeth were asymptomatic and radiographically showed repair of the lesion. Healing was achieved without any need for further endodontic surgical intervention. How to cite this article: Başoğlu A, Harorlı H, Er K. Endodontic retreatment of mandibular molars with the presence of missed middle mesial root canals: an important clinical lesion. Int Dent Res 2023;13(2):99-103. https://doi.org/10.5577/idr.2023.vol13.no2.8 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Process-related Factors Are as Important as Outcomes for Patients Undergoing Nonsurgical Root Canal Treatment, Nonsurgical Root Canal Retreatment, and Endodontic Microsurgery

IntroductionThere is considerable variation in the reporting of treatment outcomes in endodontics. Patient-centered outcomes are often inadequately reported in endodontic outcome studies. This paper explores patients’ expectations and reported outcomes in nonsurgical root canal treatment (NS-RCT), nonsurgical root canal retreatment (NS-ReTx), and endodontic microsurgery (EMS). MethodsWe used a qualitative description approach and conducted telephone and virtual semi-structured interviews with participants who had the following treatments within the preceding 3–12 months: NS-RCT (n = 10), NS-ReTx (n = 10), or EMS (n = 10). Half of these treatments were performed by senior endodontic residents in an academic setting and the other half by a community-based endodontist at a private practice. ResultsParticipants identified several outcomes that were important to them and integral to treatment success, such as tooth survival, resolution of symptoms, aesthetics, and radiographic healing. Process-related factors were as important as treatment outcomes for participants. Communicating with and educating patients during treatment increased participants’ satisfaction and lowered their stress. Dissatisfaction was linked to the lack of a comprehensive treatment and follow-up plan. Thorough planning ensured that patients were fully informed and had a structured approach to achieving their desired outcomes. ConclusionsThis study provides a list of outcomes that are important for patients undergoing NS-RCT, NS-ReTx, and EMS. These outcomes should be considered when developing a core outcome set related to endodontic treatments. Additionally, this study reports patients’ expectations regarding process-related factors that are essential for providing patient-centered care and improving patient experience.

Modern supplementary strategies of filling material removal in non-surgical root canal retreatment

O retratamento não cirúrgico é atualmente a terapia mais afetada na Endodontia em termos de desfecho clínico. O presente estudo tem como objetivo avaliar estratégias modernas para abordagens complementares na remoção de material de obturador. Assim foi realizada uma revisão narrativa da literatura nas bases de dados PubMed. Cochrane Library e Web of Science com as seguintes palavras-chave em diferentes ordens: “root canal”, “filling material removal”, “non-surgical retreatment” e “supplementary”. Para o delineamento da seleção de estudos, após a triagem dos títulos, foi realizada a retirada das duplicatas e aplicados os critérios de inclusão, em seguida foi feita a análise dos resumos e, por fim, realizada a revisão dos textos completos para seleção final dos estudos. Pesquisas adicionais foram conduzidas manualmente sob demanda. Seis tipos de estratégias de limpeza foram identificados na literatura para abordagem complementar em retratamento não cirúrgico: ativação ultrassônica e sônica passiva, ativação ultrassônica ativa, instrumentos plásticos para agitação mecânica, instrumentos metálicos para agitação mecânica, ativação multissônica e ativação a laser. Aqueles abordados na literatura têm sido associados a desempenhos mais elevados de remoção de material de obturador em comparação com sistemas de instrumentação apenas. No entanto, nenhum deles foi capaz de remover completamente o material obturador dentro do sistema de canais radiculares. Estudos clínicos controlados e randomizados são necessários para entender a real influência dessas estratégias no retratamento não cirúrgico. Há uma discrepância notável entre o volume de estudos para cada estratégia, mais estudos são necessários em alguns sistemas já contemplados. Ainda existem sistemas de ativação das soluções irrigadoras não elucidados no retratamento não cirúrgico.

Outcome of Nonsurgical Root Canal Retreatment Procedures Obturated with Warm Gutta-percha Techniques: A Longitudinal Clinical Study

IntroductionTo evaluate the success rate of nonsurgical root canal retreatment at the 2–3-year follow-up and identify the possible prognostic factors. MethodsPatients who underwent root canal retreatment at a university dental clinic were contacted for clinical and radiographic follow-up. The retreatment outcomes in these cases were based on clinical signs, symptoms, and radiographic criteria. Inter- and intraexaminer concordances were calculated using Cohen's kappa coefficient. The retreatment outcome was dichotomized into success or failure according to strict and loose criteria. The radiographic success criteria consisted of complete resolution or absence of a periapical lesion (strict criteria) or a reduction in the size of an existing periapical lesion at recall (loose criteria). χ2 tests were used to evaluate possible variables associated with retreatment outcomes (age, sex, tooth type, location, contact points, periapical status, quality of previous and final root canal filling, previous and final restoration, number of visits, and complications). ResultsOverall, 129 teeth (113 patients) were included in the final evaluation. The success rate was 80.6% under strict criteria and 93% under loose criteria. Molars, teeth with an initially higher periapical index score, and teeth with >5 mm periapical radiolucency had a lower success rate according to the strict criteria model (P < .05). When the loose success criteria were used, teeth with larger (>5 mm) periapical lesions and those that had been perforated during retreatment showed a lower success rate (P < .05). ConclusionsThe present study demonstrated that nonsurgical root canal retreatment is a highly successful procedure after an observation period of 2–3 years. Treatment success is primarily affected by the presence of large periapical lesions.

Resolution of Apical Periodontitis-induced Mental Nerve Paresthesia Through Nonsurgical Endodontic Retreatment: A Case Report

Paresthesia is a potential consequence of unsuccessful root canal treatment. Persistent infection resulting in apical periodontitis may enlarge sufficiently to involve the mental neurovascular bundle. The case presented in this report was referred for endodontic evaluation with a chief complaint of discomfort on mastication and persistent numbness of the lower left lip. Clinical and radiographic evaluation revealed incomplete primary endodontic treatment of the left mandibular second premolar with complex internal anatomy. The untreated root canal system resulted in the progression of apical periodontitis involving the left mental neurovascular bundle as confirmed by cone-beam computed tomography imaging. Nonsurgical root canal retreatment was performed over 2 visits. At the 3-year follow-up visit, the paresthesia had resolved with return of normal sensation. Nonsurgical endodontic retreatment may be sufficient to allow healing of large periapical lesions and resolve complications including paresthesia without the need for surgical intervention.

Evaluation of the Antibacterial Effect of Xylene, Chloroform, Eucalyptol, and Orange Oil on Enterococcus faecalis in Nonsurgical Root Canal Retreatment: An Ex Vivo Study.

Objectives The present ex vivo study is aimed at evaluating the antibacterial efficacy of chloroform, eucalyptol, orange oil, and xylene against E. faecalis biofilm during nonsurgical root canal retreatment. Materials and Methods Eighty single-rooted teeth were instrumented. The samples were autoclaved, infected with E. faecalis for 4 weeks, and obturated with gutta-percha. Then the teeth were randomly assigned to 4 groups (n = 20): (1) chloroform, (2) eucalyptol, (3) orange oil, and (4) xylene. In all of the groups, gutta-percha removal was conducted according to the same protocol although the solvent used in each group was different. Bacterial samples were collected after gutta-percha removal and following additional apical enlargement. Intergroup and intragroup analyses were conducted using one-way ANOVA combined with the post hoc Tukey test and the paired-sample t-test, respectively. Statistical significance was set to 0.05. Results All of the groups showed more than 99% bacterial load reduction. The least bacterial load after gutta-percha removal was observed in the chloroform group (p < 0.001). The orange oil group showed a significantly lower bacterial load compared to the eucalyptol group (p = 0.001), while it was not different from the xylene group (p = 0.953). The xylene group also had a significantly lower bacterial load compared with the eucalyptol group (p = 0.017). After apical enlargement, the chloroform group had a significantly lower bacterial load compared to the other groups. The comparison of bacterial load values before and after apical enlargement in the chloroform and eucalyptol groups showed a statistically significant difference (pcholoroform = 0.011, peucalyptol = 0.001). Conclusion Chloroform was the most effective solvent in terms of antimicrobial activity against E. faecalis followed by orange oil and xylene, which were not significantly different though, and eucalyptol. All of the solvents showed more than 99% bacterial load reduction. Chloroform and xylene revealed to be associated with favorable antibiofilm activity among the examined solvents.

Endodontic reintervention of a mandibular second premolar with four root canals: a case report

Complex anatomical variations on root canals morphology are one of the most arduous challenges in the endodontic practice. The objective of this case report is to discuss the clinical management of a mandibular left second premolar with four root canals and four distinct apical foramina. This case report has been written according to Preferred Reporting Items for Case reports in Endodontics (PRICE) 2020 guidelines. A 74-year-old patient was referred to retreat a left mandibular second premolar. The patient complained of discomfort when chewing hard food. After obtaining consent from the patient to investigate the symptoms, a thorough clinical and radiographic examination was performed. The main clinical findings observed were a moderate sensitivity to vertical percussion and mild discomfort at palpation. The periapical radiograph showed a fusion-like root with multiple canals and unsatisfactory root canal fillings associated with apical radiolucency. Based on this investigation, a diagnostic of persistent apical periodontitis was made to the tooth, and nonsurgical root canal re-treatment was proposed to the patient. After written informed consent was obtained, the procedure was performed under magnification provided by a dental operating microscope with the aid of ultrasonic tips. During the access opening and fillings removal, four root canal orifices were observed. Therefore, state-of-the-art technology such as the dental operating microscope, ultrasonics, and cone-bean computed tomography image are strong allies to manage anatomical variations.

The impact of apical periodontitis, non-surgical root canal retreatment and periapical surgery on serum inflammatory biomarkers.

AimThe aim of the study was to measure serum levels of molecular markers of inflammation in patients undergoing non‐surgical root canal retreatment (Re‐RCT) and periapical surgery (PS) for the treatment of apical periodontitis and to establish if such levels are influenced by the size of apical radiolucencies at baseline and by the treatment outcome.MethodologyA total of 115 participants were recruited (n = 50 Controls, n = 35 Re‐RCT, n = 30 PS). Preoperative periapical radiographs and cone beam CT (CBCT) scans of teeth were taken. Blood was collected from treatment groups at baseline, 3‐, 6‐, and 12‐month post‐treatment and from controls at baseline and 12 months. Serum levels of IL‐1β, IL‐6, IL‐8, TNF‐α, Pentraxin 3, ICAM‐1, VCAM‐1, hs‐CRP, FGF‐23, MMP‐2, MMP‐8, MMP‐9, C3 and ADMA were analysed using multiplex immunoassay and enzyme‐linked immunosorbent assay. Different time points within the same group were compared using Wilcoxon signed‐rank test, and differences between groups were analysed using the Mann–Whitney test. Non‐linear association between different factors was assessed using Spearman's correlation.ResultsPreoperative serum levels of FGF‐23, IL‐1β, hs‐CRP and ADMA were significantly higher in the diseased groups compared with controls (p < .001; p = .008; p < .001; p = .013, respectively). The preoperative size of the radiolucency was associated with increased levels of FGF‐23, IL‐1β and IL‐6. At 3‐months following treatment, IL‐1β, IL‐8, hs‐CRP, C3, MMP‐2 and MMP‐9 levels increased compared with baseline in treatment groups. IL‐1β and IL‐8 further increased at 6 months, whereas FGF‐23, hs‐CRP, C3, MMP2 and MMP‐9 decreased. One‐year post‐treatment, FGF‐23, pentraxin‐3 and ADMA were significantly reduced below baseline levels. At the 1‐year review, CBCT revealed that 25.9% of treated cases completely healed, while 63% were healing, and 11.1% failed. Treatment outcome was found to be influenced by preoperative levels of ADMA and IL‐8 levels at 6 months.ConclusionsBoth symptomatic and asymptomatic apical periodontitis (AP) can contribute to increased levels of molecular markers of inflammation. A further transient inflammatory markers rise after root canal retreatment and apical surgery were demonstrated. Successful endodontic treatment and periapical surgery result in a long‐term reduction in inflammatory marker levels.

The effectiveness of reciprocating instruments in the removal of root filling materials: A systematic review

Introduction: Re-establishing the health of the periapical tissues is considered to be the main objective of nonsurgical root canal retreatment in cases with posttreatment disease. Removal of filling material from the canal space is the most difficult and challenging step during retreatment, regardless of the technique/instrument used. The aim of this study was to determine the effectiveness of nickel–titanium reciprocating instruments in the removal of root canal filling material in comparison with continuous rotary shaping and retreatment instruments.Materials and Methods: Four electronic databases were used (PubMed, Google Scholar, ScienceDirect, and Scopus) as information sources. Articles describing in vitro studies carried out on extracted human teeth were included in this systematic review, while narrative, systematic review, in vivo studies, animal studies, studies published in languages other than English, and studies that used methods other than micro-computed tomography to detect root filling material were excluded from this systematic review. The studies were assessed for eligibility according to inclusion criteria by two independent reviewers; the opinion of the third reviewer was requested when one of the reviewers did not accept the study to be included.Results: Forty-one studies of 560 titles and abstracts screened were selected for full-text analysis; 26 studies were excluded, and 15 studies were included in this systematic review. Eleven studies (73%) showed a nonsignificant difference between reciprocating and rotary instruments.Conclusions: The collected studies showed no effect of motion (either reciprocation or full rotary motion) on the remnant of root canal filling materials.

Outcome of Endodontic Treatment: The Most Cited Publications

IntroductionBibliographic analysis using quantitative measurements such as citation number and citation density is a common method used to evaluate the impact of previously published studies on current research. Several bibliographic endodontic studies ranking publications based on their number of citations have been published. However, to date, a focus on the most cited articles related to the outcome of endodontic treatment is lacking. The purpose of this study was to identify the most cited publications and their citation density as related to the outcome of nonsurgical root canal treatment (NSRCT), nonsurgical root canal retreatment (NSRCR), and root canal surgery (RCS). MethodsA search of all citations regarding the outcome of NSRCT, NSRCR, and RCS was performed using the Web of Science platform. The search included key words covering all relevant categories. Only publications in the English language published between May 1960 and July 2021 were included. The publications were divided into the following groups: NSRCT, NSRCR, and RCS. Each group was further subdivided into experimentation studies and review studies. The publications were analyzed and sorted in descending order according to the number of citations that each publication has received. Only publications with 100 citations or more were included. Citation density was also assessed. ResultsThe total number of NSRCT citations found was 257; 221 (86%) were experimentation studies, and 36 (14%) were review studies. Of the 221 NSRCT experimentation studies, 41 (18.55%) had 100 citations or more. Of the 36 NSRCT review studies, 9 (25%) had 100 citations or more. The total number of NSRCR citations found was 61; 51 (83.6%) were experimentation studies, and 10 (16.4%) were review studies. Of the 51 NSRCR experimentation studies, 5 (9.8%) had 100 citations or more. Of the 10 NSRCR review studies, 2 (20%) had 100 citations or more. The total number of RCS citations found was 119; 90 (75.6%) were experimentation studies, and 29 (24.4%) were review studies. Of the 90 RCS experimentation studies, 11 (12.2%) had 100 citations or more. Of the 29 RCS review studies, 2 (6.9%) had 100 citations or more. In total, 70 publications on the outcome of endodontic treatment had 100 or more citations. Fifty publications (71.4%) pertained to the NSRCT groups, 7 publications (10%) to the NSRCR groups, and 13 publications (18.6%) to the RCS groups. ConclusionsBibliographic analysis is a beneficial aid for assessing the impact of publications studying the outcome of endodontic treatment on the field of endodontics.

Endodontic Perforation Closure by Five Mineral Oxides Silicate-Based Cement with/without Collagen Sponge Matrix.

Endodontic perforations are common accidents that occasionally happen as a result of misuse or difficult anatomy of some teeth; it may lead to teeth loss unless a good management is provided. Bioceramic (silicate-based) cements like mineral trioxide aggregate have a big role in management of such accidents. This case report aimed to evaluate the ability of five mineral oxides cement “5MO” in sealing two root canal perforations (furcation and postdrill perforations) and inducing clinical and radiographic healing in the periodontal tissues with/without the use of collagen sponge matrix. A 58-year-old healthy female was referred to our dental office complaining of severe pain in the upper left premolars' region. Periapical radiographic examination revealed unsatisfactory root canal treatment of the teeth #24 and #25 with a furcation perforation and a postdrill perforation, respectively. Cone-beam computed tomography “CBCT” scans confirmed the findings of the periapical radiography and revealed the presence of radiolucent lesions surrounding the apex of both teeth #24 and #25. The treatment plan was a nonsurgical root canal retreatment by endodontic access through the full-ceramic crowns. After three years of follow-up, CBCT scans revealed a complete healing and bone formation on both premolars. This case report indicates the use of 5MO cement for endodontic perforations management.

Efficacy of Removing Thermafil and GuttaCore from Straight Root Canal Systems Using a Novel Non-Surgical Root Canal Re-Treatment System: A Micro-Computed Tomography Analysis.

The present study aims to evaluate the effectiveness of an XP-endo non-surgical root canal re-treatment system in removing both GuttaCore and Thermafil gutta-percha carrier-based root canal filling materials from straight root canal systems using micro-computed tomography (micro-CT) analysis. The study was performed on 20 single-rooted upper teeth, which were randomly allocated into the following study groups: Group A, Thermafil and AH Plus sealer (n = 10); Group B, GuttaCore and AH Plus sealer (n = 10). Before and after the non-surgical root canal re-treatment procedure, the samples were submitted for a micro-CT analysis. The volume of the root canal filling material (mm3), the volume of the remaining root canal filling material (mm3) and the time (minutes) needed to remove the root canal filling material were also recorded. Student’s t-test was used to analyze the results. No statistically significant differences were found between the volume of the remaining root canal filling material in the GuttaCore and Thermafil root canal filling systems at the coronal third (p = 0.782), middle third (p = 0.838) or apical third (p = 0.882) of the straight root canal systems; however, the GuttaCore required a statistically significant (p = 0.037) shorter amount of time (4.72 ± 0.76 min) to be removed than the Thermafil carrier-based root canal filling material (5.92 ± 1.42 min). The XP-endo Finisher non-surgical endodontic re-treatment system removes both GuttaCore and Thermafil gutta-percha carrier-based root canal filling materials from straight root canal systems, although removal of the GuttaCore gutta-percha carrier-based root canal filling material required less time.

Frequency of additional treatments in relation to the number of root filled canals in molar teeth in the Swedish adult population.

To investigate the 5-year frequency of additional treatments in relation to the number of reported root filled canals in molar teeth in Sweden. The cohort included first and second molars in adult individuals who were registered with a root filling performed in 2009. Treatment codes corresponding to root fillings of teeth with from one up to four root filled canals were identified in the Swedish Social Insurance Agency database. The studied additional treatments were extraction, non-surgical root canal retreatment and endodontic surgery during the subsequent 5years, identified by corresponding codes for these treatments registered on these specific teeth. Differences in the frequency of additional treatments based on the number of root filled canals were analysed using chi-square test and considered statistically significant at P<0.05. In 2009, root fillings on a first or second molar tooth were registered in 100720 individuals. The study included 32901 maxillary first molars (6.4% with four root filled canals), 12763 maxillary second molars (3.3% with four root filled canals), 37703 mandibular first molars (19.2% with four root filled canals) and 17353 mandibular second molars (3.7% with four root filled canals). The total frequency of additional treatments was 14.3% (n=14425) during the 5-year observational period. Additional treatments were more frequent in teeth with 1-3 root filled canals compared to teeth with four root filled canals for maxillary first molars (15.2% vs. 12.7%, P=0.002), maxillary second molars (13.8% vs. 9.1%, P=0.007) and mandibular first molars (14.0% vs. 10.7%, P<0.001) but not mandibular second molars (15.6% vs. 13.7%, P=0.200). Over 5years, 85.7% of the included teeth were not registered with any additional treatments. Maxillary first and second molars and mandibular first molar teeth had a greater frequency of additional treatments when ≤3 root canals were filled compared to four canals.

Characterization of the differential efficacy of austenitic vs martensitic NiTi rotary files in non-surgical root canal retreatment: a micro-CT analysis.

Aim: Our study aims to characterize the differential efficacy of martensitic and austenitic files in root canal retreatment regarding defiling ability, debris management and morphometric features. Materials and methods: A total of 10 human premolar teeth with two separate fully formed roots were selected, prepared with BioRace system (BR) up to a size BR2 (0.04/25). Root canals were filled and then divided according to the file type into two groups (n = 10). Two geometrically identical files have been used with the only difference between them is heat treatment; One Curve (OC) martensitic and One Shape (OS) austenitic. Preoperative and postoperative Micro-CT scans were done for all the samples, and the percent volume of residual filling materials was calculated. Canals reshaping and remaining debris in the canals were assessed by calculating the volume of the canals before and after retreatment using Micro-CT software. Results: The percentages of removed filling materials were similar between both groups (97.2% OC vs 97.8% OS). OS was significantly faster than OC (P < 0.05). Retreatment procedure did not significantly change volume, structure model index, surface area, and canal curvature. OS group transported the canals more than OC at the apical third (P < 0.05). There were no significant differences between both groups concerning un-instrumented surface area and accumulated hard tissue debris (AHTD) (P > 0.05). Conclusion: Under the circumstances of this study, neither file systems could completely remove the filling materials. However, OC resulted in less transportation than OS in the apical one third (P < 0.05). Also, OC resulted less AHTD than OS but with no statistical difference.

Chloroform skin injury after endodontic Chloroform skin injury after endodontic retreatment: Case report

A nonsurgical root canal retreatment was initiated for the upper right second premolar in a 35-year-old healthy female patient as part of her comprehensive dental treatment. She reported severe pain during the treatment, and then the procedure was discontinued due to time limitations. The next day, she returned back to the clinic complaining of a skin injury on the right side of her face. According to the patient's history, she felt a burning sensation during the procedure when the treating clinician began using a solution from a syringe. Extraoral clinical examination revealed a dry, pink-brown skin injury extending from the right labial commissure to the middle cheek area. Since the only solution used during the first visit was chloroform, the skin injury was diagnosed as a first-degree chemical burn due to accidental chloroform skin exposure. The patient was reassured and instructed to use petroleum jelly (Vaseline) until healing was complete. After 2 weeks, the burn had healed completely without scarring, with only slight hyperpigmentation remaining in the affected area. Chloroform use should be limited to cases in which mechanical gutta-percha removal is ineffective. It should be handled with extreme caution. Chemical burns can be prevented if exposure is detected immediately and the area washed thoroughly. This clinical case is made to increase the clinicians' awareness of the hazards of chloroform.