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Title Endodontic Microsurgery (EMS) Has a Significantly Higher 4-Year Success Rate When Compared to Non-Surgical Endodontic Retreatment
Clinical Question For healthy patients requiring endodontic retreatment, is endodontic microsurgery (EMS) a more successful treatment option compared to non-surgical endodontic retreatment?
Clinical Bottom Line Endodontic microsurgery is a reliable treatment option and could be considered as first treatment alternative for patients with a failed initial root canal therapy, since it has a high success rate and predictable long-term outcome. This is supported by a recent meta-analysis and a retrospective cohort study which reported EMS to have higher success rates (92% to 94.7%) than non-surgical retreatments (80% to 82.4%) up to 4 years post-treatment. However, at follow-up periods longer that 4 years, both treatment modalities have similar outcomes.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 25595864 Kang/201518 studies/2373 patientsMeta-Analysis
Key resultsThe weighted pooled success rate of the EMS group was 92% (pooled effect size [ES] 0.919, 95% CI 0.881–0.957), which was significantly higher than that of the non-surgical retreatment group of approximately 80% (pooled ES 0.797, 95% CI 0.737–0.857) (p < 0.05). However, when the weighted pooled success rates were compared between the EMS and the retreatment groups at ≥ 4 years, the different was not statistically significant (p>0.05), with the EMS group showing 82% success (pooled ES 0.825, 95% CI 0.713–0.937). The retreatment group also showed 82% success at > 4 years (pooled ES 0.817, 95% CI 0.767–0.867). The authors analyzed the quality of the studies in this meta-analysis and ranked them as group "A" (highest quality) through group "C" (lowest quality). For the microsurgery group, the pooled success rate of group A studies was 90% (pooled ES 0.904, 95% CI 0.860–0.947), and group B was 95% (pooled ES 0.947, 95% CI 0.893–1.001); there was no group C available for analysis. For the retreatment group, the pooled success rate of group A was 74% (pooled ES 0.743, 95% CI 0.627–0.858), group B was 80% (pooled ES 0.797, 95% CI 0.750–0.843), and group C was 85% (pooled ES 0.854, 95% CI 0.818–0.890). This data indicates that as the quality of the studies decreased there was an increase in pooled success rates. This could make interpretation of the data difficult and the risk of bias should be taken into account.
#2) 29970237Curtis/201897 adult patients, 125 teeth Retrospective cohort study
Key resultsThis study employed the volumetric analysis of periapical radiolucencies suggestive of apical periodontitis in pre-surgical and post-surgical cone-beam computer tomography (CBCT) imaging. Teeth that underwent non-surgical retreatment with periapical radiolucencies had an average volumetric reduction of 62.4% at the follow-up visits. However, teeth that underwent EMS had an average volumetric reduction of 95.0% following treatment. These results show that using quantitative methods EMS resulted in greater healing rates as measured by the 3D reduction in periapical radiolucency. Using the dichotomous measure of the presence or absence of radiolucency at the follow up visits, EMS resulted in absence of radiolucency (complete healing) in 49 of 57 (86.0%) versus retreatment with lower incidence of complete healing in 28 of 68 (41.2%, P < .0001). Using a less stringent criteria that included cases with reduction in radiolucency size (“reductive healing”), EMS was 94.7% successful when compared to retreatment 82.4% (P < .05).
Evidence Search MeSH Terms: microsurgery; retreatment
Comments on
The Evidence
Validity: The meta-analysis included 18 studies (11 microsurgery, 7 non-surgical retreatment) selected using a strict screening process and well-established parameters. The authors tried to account for all confounding factors; however some of the included studies failed to disclose certain methodological criteria such as the skill level of the operators and the case selection process for non-surgical retreatment vs microsurgical treatment. Additionally, there were studies that did not define or discuss their types of failure, which is important information when studying outcomes. The authors did not examine the rate of bias for each study, but instead pooled the data based on a series of quality assessment questions. There was a greater number of high-quality studies on microsurgery than on retreatment (7 vs. 2) with success rates being 90% and 74% respectively. Interestingly, when looking at the lesser quality studies, (group B; which included 5 microsurgery and 4 retreatment studies), the success rates went up to 95% and 80%. This significant increase in success may lead to questions about the validity of these lesser quality studies (potential bias), and whether they should have been included in this analysis. The second article is a 4-year retrospective cohort study using volumetric measurement based on CBCT to quantify changes in periapical healing and/or failure. As is typical with retrospective studies, it is difficult to standardize protocols and materials (i.e., concentration NaOCl, root-end filling material, grafting vs. not grafting, among other factors). It was also difficult to completely blind examiners because of end result of each treatment is vastly different. Even with those limitations, the study had adequate sample size and assessment period. Perspective: It is widely accepted that the primary cause for failure of root canal treatment is persistent infection due to the lack adequate disinfection and the inability to successfully obturate canals (Siqueira, 2001). Non-surgical retreatment is often considered the treatment of choice for teeth with persistent apical periodontitis after initial root canal treatment. However, clinical judgment to retreat surgically or non-surgically is multifactorial and based on the level of surgical expertise of the provider, anatomical restrictions, the presence and size of an apical lesion, type and quality of the coronal restoration, quality of previous endodontic therapy, among other factors. In 2009 Torabinejad et al. authored a meta-analysis and in 2016 Del Fabbro et al. completed a Cochrane systematic review, both of which reported no significant difference in the success rates between non-surgical retreatment and EMS. Both of these reviews however, included traditional surgical techniques in their results, which are known to have lower predictability and lower success rates (Seltzer, 2010) and therefore could have skewed the surgical outcome data. Although the two studies above mentioned found EMS to be a reliable treatment option with favorable initial healing and predictable outcomes, they demonstrated a marked reduction in success with longer follow up periods. This discrepancy compared to the two included studies in this CAT is likely due to the inclusion of cases treated with traditional techniques that should not be classified as EMS. Ideally, future studies should focus on EMS and investigate its long-term success (using standardized techniques and precisely defined terms for outcome success, including patient-centered outcomes such as their effect on postoperative quality of life.
Applicability This topic is applicable for dental practitioners performing endodontic treatment, retreatment and endodontic surgery, or deciding when to refer a case for specialized treatmemt. Limitations to EMS would include patients with contraindications for osseous surgery and teeth with questionable restorations. Non-surgical retreatment or EMS could be cost-prohibitive to some socioeconomic groups, and therefore extraction with or without prosthetic replacement should be discussed as an alternative treatment option.
Specialty/Discipline (Endodontics) (General Dentistry)
Keywords Endodontics, endodontic surgery, apicoectomy, root-end surgery, microsurgery, retreatment, outcomes
ID# 3339
Date of submission: 11/12/2018spacer
E-mail dufoura@livemail.uthscsa.edu
Author Andrea DuFour D.D.S
Co-author(s) e-mail
Faculty mentor/Co-author Anibal Diogenes D.D.S., M.S., Ph.D.
Faculty mentor/Co-author e-mail DIOGENES@uthscsa.edu
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