Endodontics, Endodontic Retreatment, and Apical Surgery Versus Tooth Extraction and Implant Placement: A Systematic Review

Effect of the filling technique on the filling removal from oval-shaped canals

OBJECTIVES

This ex vivo study aimed to evaluate the influence of different filling techniques on the filling removal from oval root canals filled with bioceramic sealer.

METHODS

Thirty-six mandibular incisors with single oval canals were filled with bioceramic sealer following the techniques (n = 12): single-cone, modified McSpadden, or continuous wave of condensation, and scanned by micro-computed tomography (micro-CT). The filling was removed using the Clearsonic ultrasound tip and Reciproc system up to the R40 instrument, and the working time was recorded. The teeth were scanned again by micro-CT. Percentage of remnant volume (mm³) of the filling material, dentin thickness, and root canal transportation were measured. The data was analyzed using parametric and non-parametric tests with a significance level of 5%.

RESULTS

It took more time to remove the filling material using the continuous wave of condensation technique (p < 0.05), followed by the modified McSpadden and single-cone techniques. There was no difference (p > 0.05) when comparing the percentage of remaining filling material among the three groups, nor did it among the segments of each tooth. There was also no difference in the analysis of dentin thickness and transportation when comparing the groups (p > 0.05).

CONCLUSIONS

The filling technique did not influence the amount of remaining filling material, dentin thickness, and transportation. The working time was longer with thermoplastic filling techniques.

CLINICAL RELEVANCE

Endodontic retreatment in teeth filled with bioceramic sealers increases with their use. Several techniques are used to fill the root canals, thus, it is important to know whether the filling technique influences the non-surgical endodontic retreatment.

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.

Assessment of Debris Extrusion in Curved Canals: An In Vitro Analysis of Various Single-File Endodontic Instrumentation Systems

Objectives

Rotary single-file endodontic systems are commonly used for root canal treatment. However, very few studies have evaluated the apical extrusion of debris generated by these systems during canal preparation at normal body temperature in laboratory conditions. The aim of this study was to evaluate the amount of apically extruded debris caused by seven different single-file endodontic instrumentation systems at body temperature in mandibular molar teeth with curved root canals.

Methods

One hundred forty mandibular first permanent molars were randomly divided into seven groups (n = 20) to be prepared by one of the following systems at 35°C: Reciproc Blue (REC Blue), WaveOne Gold (WOG), One Reci (OR), Neoniti, HyFlex EDM (HEDM), One Curve (OC), or XP Shaper (XPS). Debris was collected into preweighted Eppendorf tubes. The weight of the extruded debris was recorded by subtracting the weight of the tooth-free apparatus from the post-procedure weight. Data were analyzed by one-way ANOVA and Tukey's tests (p  < 5%).

Results

REC Blue, WOG, and OR groups extruded significantly more debris from the apex than XPS, OC, and Neoniti groups (p  < 0.05). No significant difference was observed among the XPS, OC, Neoniti, and HEDM groups (p  > 0.05).

Conclusion

All the instruments were associated with debris extrusion. However, REC Blue, WOG, and OR extrude significantly more debris than other instruments. The amount of debris with different files was REC Blue > OR > WOG > HEDM > OC > Neoniti > XPS. XPS, Neoniti, and OC caused significantly less extrusion of debris than REC Blue, WOG, and OR.

Outcome of Contemporary Nonsurgical Endodontic Retreatment: A Systematic Review of Randomized Controlled Trials and Cohort Studies

INTRODUCTION

The success rates of NS-ReTx have varied across decades of prior research. Nonetheless, recent endodontic advances have substantially enhanced case management. This systematic review aimed to identify rigorous studies on contemporary NS-ReTx, investigating both periapical healing-evaluated strictly for complete resolution or loosely for size reduction of periapical radiolucency-and success, denoting clinical normalcy combined with periapical healing.

METHODS

We systematically searched MEDLINE, Embase, Web of Science, the Cochrane Library, and gray literature from January 1988 to December 2022. Article selection and data extraction were independently conducted by 3 reviewers. Selected studies underwent risk of bias assessment, and evidence quality using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Meta-analysis and meta-regression established pooled outcome rates, 95% confidence intervals (CIs), and significant clinical prognostic factors (P < .05).

RESULTS

Twenty-nine articles were included. Pooled periapical healing rates using strict and loose criteria were 78.8% (95% CI: 75.2-82.4) and 87.5% (95% CI: 83.8-91.2), respectively. Pooled success rates using strict and loose criteria were 78.0% (95% CI: 74.9-81.2) and 86.4% (95% CI: 82.6-90.1), respectively. Meta-regression analyses revealed significant influences on NS-ReTx outcomes (P < .05), including periapical status, lesion size, apical root filling extent, and follow-up duration.

CONCLUSIONS

Contemporary NS-ReTx shows encouraging outcomes, achieving periapical healing and success rates ranging from approximately 78% (strict criteria) to 87% (loose criteria). The absence of or smaller preoperative lesions, adequate root filling length, and extended follow-ups significantly improve NS-ReTx outcomes. Integrating these factors into treatment planning is pivotal for optimizing the outcome of NS-ReTx.

Survival, complications, and patient-reported outcomes of endodontically treated teeth versus dental implant-supported prostheses: A systematic review

STATEMENT OF PROBLEM

Decision making for compromised teeth involving the choice between endodontic treatment and tooth extraction followed by an implant-supported prosthesis is challenging. However, systematic reviews examining studies using the same patients or clinical settings to provide conclusive evidence regarding the best approach are lacking.

PURPOSE

The purpose of this systematic review was to compare the survival rate, complications, failure, and patient-reported outcomes of endodontically treated teeth and implant-supported prostheses.

MATERIAL AND METHODS

After the protocol had been registered at the International Prospective Register of Systematic Reviews (PROSPERO), PubMed, Scopus, and the Cochrane Database of Systematic Reviews were searched from database inception to July 2023 with no language restriction. A manual literature search was performed. The review protocol was based on the population, intervention, comparator, outcome, and study design (PICOS) criteria and included all observational and experimental human studies that directly compared the survival, complications, and patient-reported outcomes of teeth with pulpal and periapical disease after all types of endodontic treatment and subsequent restoration and tooth extraction followed by an implant-supported prosthesis. The risk of bias of the included studies was assessed by using the modified Newcastle-Ottawa scale.

RESULTS

Eight observational studies were included in this systematic review: 3 retrospective cohort and 5 case-control studies. Three included studies revealed no difference in survival rate between endodontically treated teeth and implant-supported prostheses during the first 3 years, but the survival of endodontically treated teeth declined over time with a higher failure rate than implant-supported prostheses. In contrast, the other 3 included studies reported lower survival rate for implant-supported prostheses and more complications. In terms of patient-reported outcomes, patients were generally satisfied with both treatment modalities, with notable improvements in oral health-related quality of life in those receiving endodontic treatment.

CONCLUSIONS

Whether implant-supported prostheses or endodontically treated teeth are better in terms of survival outcome is unclear. Improved oral health-related quality of life was found after endodontic treatment.

In vitro effects of Er: YAG laser-activated photodynamic therapy on Enterococcus faecalis in root canal treatment

OBJECTIVE

Photodynamic therapy (PDT) plays an important role for root canal disinfection. Nevertheless, the effect of photosensitizers penetrating dentin tubules is limited, which ultimately impedes the disinfection effect of PDT. The study implements an Er: YAG laser to activate methylene blue, the photosensitizer, to determine the bactericidal impact of PDT on Enterococcus faecalis in vitro root canals.

METHODS

We obtained 53 single root canal teeth with intact roots, standardized the root to 9 mm. The root canals were prepared using ProTaper rotary files. Subsequently, the teeth were sterilized, and Enterococcus faecalis was cultured for 3 weeks in vitro using brain heart infusion (BHI). The model of Enterococcus faecalis root canal infection of teeth was constructed by observing Enterococcus faecalis through electron microscope scanning. The teeth were randomly allocated to five treatment groups (n = 10): control, NaOCl, NaOCl + Er: YAG, PDT, and PDT + Er: YAG. Following treatment, the number of colony forming units (CFU)/ml was assessed for each group. Statistical analysis was conducted using one-way ANOVA, with post-hoc analysis using Tukey's test for multiple comparisons.

RESULTS

The colony counts in the remaining groups were significantly lower compared to the control group (P<0.001). Using PDT alone had the least impact on reducing colonies, while using PDT and Er: YAG laser together resulted in a significant reduction in colony counts (P<0.001). There was no significant difference in colony counts reduction between the NaOCl + Er: YAG group and the PDT + Er: YAG group (P = 1.000).

CONCLUSIONS

The combination of Er: YAG laser and PDT significantly enhanced the bactericidal efficacy of PDT against Enterococcus faecalis in root canals. It had a similar impact on eliminating Enterococcus faecalis when compared to the effect of using Er: YAG laser and NaOCl.

Endodontic Orthograde Retreatments: Challenges and Solutions

Endodontic orthograde retreatments are considered one of the possible treatment options in case of post-treatment diseases considering the promising results present in the literature. Despite this, a plethora of articles have been published on this topic, and drawing conclusions could be challenging. For this reason, this review aims to summarize the crucial points on each aspect of non-surgical endodontic retreatments, discussing and comparing the current protocols, techniques, materials, and indications. Taking into consideration data from the literature, in terms of diagnosis, CBCT should be considered the first choice, since it can thoroughly affect the diagnosis and treatment plan. Regarding the procedural phases, some conclusions can be drawn: when present, coronal restoration materials such as crowns, partial prostheses, post, and core should be removed; the use of magnification devices, ultrasonic instruments, and an in-depth interpretation of radiographic images with both 2D and 3D images are strongly recommended during the orifice location; additional protocols such as irrigants activation, ultrasonic cleaning, and rotary or reciprocating instrumentation of treated canals are strongly recommended for filling materials removal and to achieve a high-quality chemo-mechanical disinfection; perforations should be treated as soon as possible, and the material of choice to treat them is the MTA or other calcium-silicate-based repair materials; the presence of ledges does not intrinsically reduce the success rate of RCRts if properly managed; in case of instrument fragments, their removal should be considered as the first treatment option, however many variables should be considered to select the proper technique or consider the option of bypassing.

Effectiveness of intentional replantation in managing teeth with apical periodontitis: A systematic review

BACKGROUND

Intentional replantation (IR) to treat disease of endodontic origin remains controversial. While IR has been advocated by some clinicians as another valid treatment option, others consider it as a treatment procedure of last resort.

OBJECTIVE

To systematically review and critically evaluate the effectiveness of IR compared with nonsurgical root canal treatment/retreatment or apical surgery in terms of clinical and patient-related outcomes in managing permanent teeth with apical periodontitis (AP).

METHODS

A literature search of five databases (PubMed, Embase, Scopus, Web of Science and Cochrane Central register of Controlled Trials), and the grey literature (Networked Digital Library of Theses and Dissertations, Open Access Theses and Dissertations, DART-Europe E-theses Portal, British Library E-Theses Online Service), from inception to November 2021, was conducted. Randomised clinical trials, comparative clinical trials (CCTs), nonrandomised, retrospective, and prospective comparative cohort and case-control two arm studies which evaluated clinical and/or patient-related outcomes of permanent teeth with AP treated with IR compared with nonsurgical root canal treatment/retreatment or apical surgery were identified. The quality of the studies was appraised using the Cochrane risk of bias tool for randomized trials (RoB 2.0), the Robins-I for nonrandomized controlled clinical trials and the Newcastle-Ottawa scale for observational studies. Two independent reviewers were involved in the literature selection, performed the data extraction and the appraisal of the studies identified; disagreements were resolved in conjunction with a third reviewer.

RESULTS

No comparative study was identified from the literature search. Four longitudinal studies (one prospective and three retrospective) were identified during the screening of titles and abstracts but were excluded after reading the full text, because only IR was evaluated (single arm studies).

DISCUSSION

The available evidence on IR is mainly based on observational studies, which reported high overall mid- to long-term survival, and low complication rates. The results suggest that IR may represent an alternative treatment procedure to solve problems of endodontic origin. However, in the absence of high-quality evidence from CCTs, clinical decision-making should be on a case-by-case basis and in accordance with the clinician's experience and the patient's preference.

CONCLUSION

Clinical studies showed that IR may be a treatment modality to manage problems of endodontic origin. However, clinical trials comparing the effectiveness of IR with nonsurgical root canal treatment/retreatment or apical surgery are still required given the paucity of evidence.

Evaluating the stress of root canal treatment in patients and dentists compared to other dental treatments: A systematic review and meta-analysis

This systematic review aimed to investigate whether root canal treatment caused greater stress than other dental treatments for patients and dentists. All peer-reviewed literature published in English between January 1990 and January 2023 was included. This included randomized/non-randomized control trials, cohort studies, case-control studies, and cross-sectional studies. An electronic search used PubMed, Scopus, Medline, Cochrane Collaboration, and Embase. Hand searching supplemented the screening pool. Studies examining physiological or psychological stress measures within patients or providers of dental treatment (dentists, dental specialists, and dental students) were eligible. The study must have reported on the stress outcome for root canal treatment and at least one other dental procedure. After screening 3639 eligible records, there were 23 studies included, varying from very-low to low certainty of evidence. This review found that root canal treatment was more psychologically stressful for patients than routine restorative or cleaning procedures. However, the stress of root canal treatment relative to other dental procedures, especially extractions, was inconclusive for both dental patients and providers. Since patients regard root canal treatment as more stress-evoking than other routine dental procedures, providers should endeavour to minimise their own bias toward root canal treatment when providing adequate information for an informed treatment choice.

Biofabrication of engineered dento-alveolar tissue

Oral health is essential for a good overall health. Dento-alveolar conditions have a high prevalence, ranging from tooth decay periodontitis to alveolar bone resorption. However, oral tissues exhibit a limited regenerative capacity, and full recovery is challenging. Therefore, regenerative therapies for dento-alveolar tissue (e.g., alveolar bone, periodontal membrane, dentin-pulp complex) have gained much attention, and novel approaches have been proposed in recent decades. This review focuses on the cells, biomaterials and the biofabrication methods used to develop therapies for tooth root bioengineering. Examples of the techniques covered are the multitude of additive manufacturing techniques and bioprinting approaches used to create scaffolds or tissue constructs. Furthermore, biomaterials and stem cells utilized during biofabrication will also be described for different target tissues. As these new therapies gradually become a reality in the lab, the translation to the clinic is still minute, with a further need to overcome multiple challenges and broaden the clinical application of these alternatives.

Surgical endodontic treatment of maxillary incisors: Case report

This study aims to highlight the possibility of an effective endodontic surgical surgery when nonsurgical treatment of the right maxillary anterior teeth has failed. One year after the apicoectomy, the periapical lesion has completely healed, new bone has formed, and the patient is symptom-free.

Outcomes reporting in systematic reviews on non-surgical root canal treatment: A scoping review for the development of a core outcome set

BACKGROUND

Studies related to non-surgical root canal treatment are amongst the most frequently performed clinical studies in endodontics. However, heterogeneity in reporting outcomes and lack of standardization is a significant challenge to evidence synthesis and guideline development.

OBJECTIVES

The aims of the present scoping review were to (a) identify outcomes reported in systematic reviews evaluating non-surgical root canal treatment; (b) identify how and when the reported outcomes were measured; (c) assess possible selective reporting bias in the included studies. The information obtained in this study should inform the development of a core outcome set (COS) for non-surgical root canal treatment.

METHODOLOGY

Structured literature searches were performed to identify systematic reviews on non-surgical root canal treatments published in English between January 1990 and December 2020. Two reviewers undertook study selection and data extraction. Outcomes were categorized according to a healthcare taxonomy into five core areas (survival, clinical/physiological changes, life impact, resource use, and adverse events). The outcome measurement tools and length of follow-up were recorded.

RESULTS

Seventy-five systematic reviews were included, of which 40 included meta-analyses. Most reviews reported on physiological and clinical outcomes, primarily pain and/or radiographic assessment of periapical status, and a variety of measurement tools and scales were used. Few reviews focused on tooth survival, life impact, resources, and adverse events. The heterogeneity amongst the reviews was large on all parameters. Less than 40% of the reviews assessed the risk of selective reporting.

DISCUSSION

Overall aims of the included reviews were highly heterogenic; thus, outcomes and how they were measured also varied considerably. Patient-centred outcomes and the use of resources were rarely reported on.

CONCLUSIONS

Most studies reported on physiological and clinical outcomes, in particular pain and/or radiographic healing. Measurement tools, scales, thresholds, and follow-up periods varied greatly within each outcome, making comparison across studies complicated. Less than 40% of the reviews assessed risk of selective reporting; thus, selective bias could not be ruled out. The presented information on reported outcomes, measurement tools and scales, and length of follow-up may guide the planning of future research and inform the development of a COS for non-surgical root canal treatment.

Treatment of a large through and through periapical lesion using guided tissue regeneration: A case report of 2 years follow-up

Proper removal of the diseased tissue, debriding the canal system, and sealing the defect or cavity, the surgeon prevents or reduces the spread of microorganisms within the periradicular tissues. Treatment modalities following the failure of root canal treatment (RCT) are root canal retreatment (ReRCT). Regeneration of periapical defects may have a significant problem in periradicular surgery. In such circumstances, the gingival connective tissue can proliferate, or the oral epithelium can migrate into the defect, preventing the development of normal trabecular bone. Hard tissue can be restored using guided tissue regeneration (GTR) in conjunction with endodontic treatment for endodontic-periodontal lesions. Treatment of large periapical defects using GTR increases overall treatment success.

Quality of life and satisfaction of patients two years after endodontic and dental implant treatments performed by experienced practitioners

OBJECTIVES

To compare oral health related quality of life (OHRQoL) and patients´ satisfaction with root canal treatment (RCT) and dental implant (DI) therapy performed by experienced practitioners.

METHODS

Patients with both an RCT and a DI performed respectively by an endodontist and an oral surgeon with more than 15 years of experience two years prior to the study were included. The survival and satisfactory outcome of both treatments were verified with clinical and radiographic data. Participants completed two constructed questionnaire (one for each treatment). OHRQoL assessment included 24 items (OHIP-14 plus other relevant 10 items from the original OHIP-49 questionnaire). Satisfaction regarding duration, cost and pain (both during and after treatment) of treatment was assessed with a 0-10 scale and perceptions with true/false questions. Weighted sums for each dimension, total OHIP scores, prevalence of impact and general satisfaction of patients were then calculated for DI and RCT and compared using the Wilcoxon test for related samples. Patients´ perceptions were compared with Chi-square test.

RESULTS

Total OHIP scores were low for both treatments (8.82 and 7.87, respectively for RCT and DI). No significant differences were detected in OHIP total score or any dimension, except for physical pain (significantly higher for RCT than DI (p=0.044)). All patients were satisfied with both treatments; however, patients recalled that pain during treatment was significantly worse for RCT than DI (p=0.003).

CONCLUSIONS

High long-term OHRQoL and satisfaction is expected with either DI or RCT performed by experienced practitioners; however, physical pain dimension is higher for RCT.

CLINICAL SIGNIFICANCE

This study demonstrated a high satisfaction and long-term quality of life of patients undergoing both DI and RCT if treatments provide a functional balance and are performed by experienced practitioners. Very importantly, all participants had received both treatment modalities and being their own control eliminates individual variability.

Outcomes reporting in systematic reviews on surgical endodontics: A scoping review for the development of a core outcome set

BACKGROUND

Evidence-informed decision-making in healthcare relies on the translation of research results to everyday clinical practice. A fundamental requirement is that the validity of any healthcare intervention must be supported by the resultant favourable treatment outcome. Unfortunately, differences in study design and the outcome measures evaluated often make it challenging to synthesise the available research evidence required for secondary research analysis and guideline development. Core outcome sets (COS) are defined as an agreed standardised set of outcomes which should be measured and reported as a minimum in all clinical trials on a specific topic. The benefits of COS include less heterogeneity, a reduction in the risk of reporting bias, ensuring all trials contribute data to facilitate meta-analyses, and given the engagement of key stakeholders, it also increases the chances that clinically-relevant outcomes are identified. The recognition of the need for COS for assessing endodontic treatment outcomes lead to the development of Core Outcome Sets for Endodontic Treatment modalities (COSET) protocol, which is registered (No. 1879) on the Core Outcome Measures in Effectiveness Trials (COMET) website.

OBJECTIVES

The objectives of this scoping review are to: (1) identify the outcomes assessed in studies evaluating surgical endodontic procedures; (2) report on the method of assessment used to measure the outcomes; (3) and assess selective reporting bias in the included studies. The data obtained will be used to inform the development of COS for surgical endodontics.

METHODS

A structured literature search of electronic databases and the grey literature was conducted to identify systematic reviews on periradicular surgery (PS), intentional replantation (IR) and tooth/root resection (RR), published between January 1990 and December 2020. Two independent reviewers were involved in the literature selection, data extraction and the appraisal of the studies identified. The type of intervention, outcomes measured, type of outcomes reported (clinician- or patient-reported), outcome measurement method, and follow-up period, were recorded using a standardised form.

RESULTS

Twenty-six systematic reviews consisting of 19 studies for PS, three studies for IR and four studies for RR were selected for inclusion. Outcome measures identified for PS and IR included pain, swelling, mobility and tenderness, outcomes related to periodontal/soft tissue healing (including sinus tract), periradicular healing, tooth survival, life impact (including Oral-Health-Related-Quality-of-Life), resource use and/or adverse effects. For RR, in addition to tooth survival, endodontic complications, and adverse effects, the outcome measures were primarily periodontal-related, including pocket depth reduction, attachment gain, periodontal disease, and periodontic-endodontic lesions. The majority of outcome measures for PS, IR, and RR were assessed clinically, radiologically and/or via patient history. Specific tools such as rating scales (Visual Analog Scale, Verbal rating Scale, Numerical Rating Scale, and other scales) were used for the assessment of pain, swelling, and tenderness, and validated questionnaires were used for the assessment of oral health-related quality of life. The range of follow-up periods were variable, dependent on the outcome measure and the type of intervention.

CONCLUSIONS

Outcome measures, method of assessment and follow-up periods for PS, IR and RR were identified and categorised to help standardise the reporting of outcomes for future research studies. Additional outcome measures that were not reported, but may be considered in the COSET consensus process include loss of root-end filling material, number of clinic visits, surgery-related dental anxiety and muco-gingival aesthetic-related measures, such as scarring, black triangles, root surface exposure, and tissue discolouration.

Effectiveness and safety of rotary and reciprocating kinematics for retreatment of curved root canals: a systematic review of in vitro studies

Objectives

This systematic review (register-osf.io/wg7ba) compared the efficacy and safety of rotary and reciprocating kinematics in the removal of filling material from curved root canals.

Materials and Methods

Only in vitro studies evaluating both kinematics during retreatment were included. A systematic search (PubMed/MEDLINE, Scopus, and other databases, until January 2021), data extraction, and risk of bias analysis (Joanna Briggs Institute checklist) were performed. Efficacy in filling removal was the primary outcome.

Results

The search resulted in 2,795 studies, of which 15 were included. Efficacy was measured in terms of the remaining filling material and the time required for this. Nine studies evaluated filling material removal, of which 7 found no significant differences between rotary and reciprocating kinematics. Regarding the time for filling removal, 5 studies showed no difference between both kinematics, 2 studies showed faster results with rotary systems, and other 2 showed the opposite. No significant differences were found in apical transportation, centering ability, instrument failure, dentin removed and extruded debris. A low risk of bias was observed.

Conclusions

This review suggests that the choice of rotary or reciprocating kinematics does not influence the efficacy of filling removal from curved root canals. Further studies are needed to compare the kinematics safety in curved root canals.

Robotic and Microrobotic Tools for Dental Therapy

Robotic and microrobotic tools such as dental operating microscopes and dental endoscopes are being used extensively in dental therapy, which have a significant impact on dental therapy and education. Herein, this paper reviews the state of the art of robotic and microrobotic tools for dental therapy. This article starts with a brief introduction of current robotic and microrobotic tools for dental therapy and then displays their applications in various dental problems; strengths and weaknesses are also surveyed. Lastly, the conclusion and outlook are discussed, referring to the emerging dental clinic problems and demands. This review is expected to provide guidelines for the therapeutic application of robotic and microrobotic tools and to promote the development of robots in dentistry.

Geminated Maxillary Incisors: The Success of an Orthodontic Conservative Approach: 15 Years Follow-Up Study

Tooth gemination is often presented clinically and radiologically as merged crowns or “megadonts” with or without a longitudinal fissure, single root, and a single pulp chamber. The increased mesiodistal width of these teeth results in poor anterior aesthetics, anterior crowding, and incisor rotation. Our aim is to present a conservative non-extraction orthodontic approach that provides both good aesthetics and long-term stability. It aims to achieve extra space to incorporate the megadonts into the dental arch and to exceed “super” class I dental relationships. Accordingly, this study shows that geminated teeth were successfully retained by means of conservative non-extraction orthodontic mechanotherapy and without premolar extractions or enamel reduction. It demonstrated stability during a long-term 15-year follow-up, in addition to high patient satisfaction, good aesthetics, and periodontal health. The solution protocol is definitive and achieved the aesthetic, psychological, and functional objectives at a feasible cost. Thus, this treatment has proven to be preferable to other alternative surgical prosthodontic and endodontic approaches in terms of its long-term stability, and by providing a solution that does not necessitate further multidisciplinary interventions. Dental practitioners in the fields of pediatric dentistry, endodontics and prosthodontics should be well aware of this option.

Apical Extrusion of Debris during Root Canal Preparation with ProTaper Next, WaveOne Gold and Twisted Files

(1) Background: Apical extrusion of debris is an example of a complication that may arise during root canal treatment, and it has been proven to be an unavoidable occurrence during endodontic treatment by numerous authors. Even though it may not hinder the long-term outcome of treatment, it may lead directly to increased levels of postoperative pain and, therefore, lower levels of patient acceptance and satisfaction. The aim of the study was to assess the weight of apically extruded debris during root canal preparation with instruments that use different movement kinematics (rotary, reciprocating, and adaptive motion); (2) Methods: The study was performed using the Myers and Montgomery model. Sixty human premolar teeth were inserted into preweighed Eppendorf tubes and randomly classified into three groups. After manual glide-path preparation, teeth in each group were instrumented to working length set 1 mm short of the anatomical apex using the standard sequence provided by the manufacturers (for Group 1: ProTaper Next X1 & X2; for Group 2: WaveOne Gold Primary, for Group 3: Twisted Files SM1-SM3). Root canals were irrigated with 1 mL of 0.9% NaCl solution between each file insertion. The tubes with collected debris were stored in an incubator at 70 °C for 5 days in order to evaporate the liquid component. Measurement of the weight of extruded debris was performed by subtracting the preinstrumentation from the postinstrumentation weight of the tubes. The results were analyzed with Kruskal-Wallis ANOVA, with significance level set at 0.05; (3) Results: The weight of extruded debris was 0.337 mg (SD = 0.148) for Group 1, 0.305 mg (SD = 0.201) for Group 2, and 0.348 mg (SD = 0.135) for Group 3. (4) Conclusions: Engine-driven root canal preparation with the use of instruments ProTaper Next, WaveOne Gold and Twisted Files that use different movement kinematics (rotary, reciprocating, and adaptive motion) was associated with apical extrusion of debris to a similar extent.

Impact of Periodontal Attachment Loss on the Outcome of Endodontic Microsurgery: A Systematic Review and Meta-Analysis

Background and Objectives: Endodontic microsurgery (EMS) aims to eradicate the sources of infection once the apical root resection removes most of the infected anatomical structures and repairs potential procedural errors in the apical region. An endodontic-periodontal lesion yields a pathological communication between the pulp and the periodontium. The purpose of this systematic review and meta-analysis is to evaluate the impact of periodontal attachment loss on the outcome of teeth submitted to EMS. Materials and Methods: PRISMA guidelines were followed. An electronic search was performed in EBSCOhost, Embase and PubMed databases with the following search key: (“endodontic microsurgery” AND “outcome”). No filters were used concerning the year of publication or language. Only randomized clinical trials, prospective and retrospective clinical studies in humans, with a minimum one-year follow-up, defined clinical and radiographic outcome criteria and estimable success rate for endodontic-periodontal lesion were included. Statistical analysis was performed using OpenMeta[Analyst] software. Results: Of a total of 113 articles, 34 were selected for full-text reading after duplicates deletion and title and abstract analysis. Thirteen and six studies were included in the systematic review and meta-analysis, respectively. A total of 2775 pooled teeth were submitted to EMS, of which 492 teeth and 4 roots had periodontal involvement. According to the qualitative analysis, success rates of the endodontic-periodontal group ranged from 67.6% to 88.2%. Meta-analysis revealed that the absence of periodontal attachment loss was predictive of a higher likelihood of success with an odds ratio of 3.14. Conclusions: Periodontal attachment loss presents a risk factor for EMS outcome. Although endodontic-periodontal lesions were associated with lower success rates considering a 1 to 10 years follow-up period, long-term successful prognosis following EMS has been reported, therefore presenting a fully valid and viable therapeutic option for the management of this type of lesions.

A commentary on strategic extraction

BACKGROUND

Advancements in strategies to maintain compromised teeth combined with a greater understanding of risks associated with dental implants invite a reassessment of the benefits of strategic extraction of a tooth with a questionable prognosis or of limited strategic value.

METHODS

Evidence of the management of compromised teeth and decision making for strategic extraction was reviewed. Additionally, the risks for peri-implantitis were evaluated from the perspective of patient centric, biologic, and biomechanical complications.

RESULTS

Recent clinical innovations support a more predictable maintenance of compromised dentition, and the clinical literature provides evidence of the risks associated with dental implants.

CONCLUSIONS

Because of the improvements in dental management of compromised dentition, strategic extraction should be deferred, whenever possible, to avoid complications associated with peri-implantitis.

Expected Costs of Primary Dental Treatments and Endoscopic Sinus Surgery for Odontogenic Sinusitis

OBJECTIVES

Treatment of odontogenic sinusitis (ODS) due to apical periodontitis (AP) is highly successful when both dental treatment and endoscopic sinus surgery (ESS) are performed. Variation exists in the literature with regard to types and timing of dental treatments and ESS when managing ODS. This study modeled expected costs of different primary dental and sinus surgical treatment pathways for ODS due to AP.

STUDY DESIGN

Decision-tree economic model.

METHODS

Decision-tree models were created based on cost and treatment success probabilities. Using Medicare and consumer online databases, cost data were obtained for the following dental and sinus surgical treatments across the United States: root canal therapy (RCTx), revision RCTx, apicoectomy, extraction, dental implant, bone graft, and ESS (maxillary, ± anterior ethmoid, ± frontal). A literature review was performed to determine probabilities of dental and sinus disease resolution after different dental treatments. Expected costs were determined for primary dental extraction, RCTx, and ESS pathways, and sensitivity analyses were performed.

RESULTS

Expected costs for the three different primary treatment pathways when dental care was in-network and all diseased sinuses opened during ESS were as follows: dental extraction ($4,753.83), RCTx ($4,677.34), and ESS ($7,319.85).

CONCLUSIONS

ODS due to AP can be successfully treated with primary dental treatments, but ESS is still frequently required. Expected costs of primary dental extraction and RCTx were roughly equal. Primary ESS had a higher expected cost, but may still be preferred in patients with prominent sinonasal symptoms. Patients' insurance coverage may also impact decision-making.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Single-Tooth Rehabilitation Combining Root Displacement and Crown Lengthening Two-Year Follow-Up: A Case Report

CLINICAL RELEVANCE

Combined techniques to expose circumferential tooth structure associated with subsequent restoration may represent a valid option in many situations. This case provides an example of the successful management of the anterior tooth rehabilitation combining root displacement and crown lengthening.

SUMMARY

Rehabilitation of an extensively compromised single anterior tooth represents an intriguing challenge for dentists, particularly when the rehabilitation involves esthetic, psychosocial, and functional requirements. The success in rehabilitating a patient with a conservative approach depends on a critical evaluation of the remaining structures, precise treatment plan, systematic treatment strategies, and patient compliance. In this case, the patient's chief complaint was the undesirable appearance of the maxillary right lateral, caused by the displacement of the post and crown. Clinical examination revealed a remaining tooth with coronal fracture, severe loss of tissue due to caries, and absence of ferrule effect. Radiographic examination revealed that the fracture margin was located subgingival. This case report describes a single-tooth rehabilitation involving a combination of root displacement via orthodontic extrusion and crown lengthening. The rehabilitation was followed by post-and-core restoration using a prefabricated glass fiber post associated with a disilicate lithium crown. The clinical decision making and combined effect of both treatment strategies are explained in this report. The treatment required three months, including recovery times after surgery and the placement of the provisional crown. The patient was esthetically and functionally satisfied with the restoration. Patient follow-up examination was performed 24 months after the treatment. This clinical report contributes to the clinical practice and exemplifies the possibility of rehabilitating the natural tooth using combined techniques, which may offer particular advantages regarding prognosis and invested efforts.

Insensitivity of dental pulp stem cells migration to substrate stiffness

Dental pulp stem cells (DPSCs) are a promising cell source for regeneration of dental pulp. Migration is a key event but influence of the microenvironment rigidity (5 kPa at the center of dental pulp to 20 GPa for the dentin) is largely unknown. Mechanical signals are transmitted from the extracellular matrix to the cytoskeleton, to the nuclei, and to the chromatin, potentially regulating gene expression. To identify the microenvironmental influence on migration, we analyzed motility on PDMS substrates with stiffness increasing from 1.5 kPa up to 2.5 MPa. We found that migration speed slightly increases as substrate stiffness decreases in correlation with decreasing focal adhesion size. Motility is relatively insensitive to substrate stiffness, even on a bi-rigidity PDMS substrate where DPSCs migrate without preferential direction. Migration is independent of both myosin II activity and YAP translocation after myosin II inhibition. Additionally, inhibition of Arp2/3 complex leads to significant speed decrease for all rigidities, suggesting contribution of the lamellipodia in the migration. Interestingly, the chromatin architecture remains stable after a 7-days exposure on the PDMS substrates for all rigidity. To design scaffold mimicking dental pulp environment, similar DPSCs migration for all rigidity, leaves field open to choose this mechanical parameter.

Dentinal Microcracks Induced by Endodontic Procedures: Suggested Design for Experimental Studies Using Micro-Computed Tomography and Strain Gauges

INTRODUCTION

The present study aimed to describe an in vitro study model to investigate root surface strain (RSS) and its correlation with the initiation/propagation of microcracks during different endodontic procedures.

METHODS

Four lower human incisors extracted microcrack free were selected by micro-computed tomographic imaging. Two strain gauges were bonded to the root surface of each incisor. Then, the teeth were prepared to reproduce the periodontal ligament artificially. The gauges were attached to a data acquisition system. The RSS was recorded during the entire endodontic procedure, which consisted of accessing the endodontic cavity, cleaning, shaping preparation with an Mtwo rotary system (VDW, Munich, Germany), and filling with a standardized technique. Each incisor was submitted to a different retreatment protocol and supplementary cleaning method as follows: (1) Reciproc (RC, VDW) + Flatsonic (FS; Helse, Santa Rosa de Viterbo, Brazil), (2) RC + XP-endo Finisher (XPF; FKG Dentaire, La Chaux-de-Fonds, Switzerland), (3) Mtwo retreatment (MR) + FS, and (4) MR + XPF. Finally, the teeth were rescanned to establish the postoperative microcrack formation by 2 well-trained and blinded examiners.

RESULTS

The maximum and minimum RSS values were -120 and 510 microstrains, respectively, for all of the files. RC showed the highest RSS values during endodontic retreatment compared with MR. FS demonstrated a higher variation between the minimum and maximum RSS than XPF. No microcracks were observed in the specimens.

CONCLUSIONS

This preliminary study proposed an experimental model that would combine 2 methods to evaluate the effects of endodontic systems on dentin. Although strain gauges would provide data on the stresses created, the pre- and postoperative evaluation of micro-computed tomographic images would enable microcrack formation to be determined.

Resolution of a Cystic Endodontic-Periodontal Lesion Utilizing Combined Apicoectomy And Guided Tissue Regeneration: A Case Report

INTRODUCTION

Endodontic-periodontal combined lesions pose a treatment challenge for clinicians, especially when the lesion is persistent and does not show signs of healing after initial endodontic treatment. This case report describes interdisciplinary management of a non-healing combined endodontic-periodontal lesion related to a peri-apical cyst, through a combined approach of apicoectomy and guided tissue regeneration (GTR) with enamel matrix derivative (EMD). Most documented cases have been treated in a sequential manner, with minimal literature present on the effects of a combined approach utilizing EMD for the treatment of these lesions.

CASE PRESENTATION

A 72-year-old male patient presented with an endodontic-periodontal lesion at tooth #31 initially treated with nonsurgical root canal therapy. The lesion was not responsive to initial endodontic treatment. The patient was informed of questionable prognosis, however wished to save the tooth. Tooth #31 was treated via a combination approach of apicoectomy with bioceramic putty retrograde filling, followed by GTR of the defect using allograft, EMD, and resorbable barrier membrane. The lesion was biopsied and diagnosed as a periapical cyst. Clinical and radiographic examination at 1 year showed resolution of lesion, reduction in probing depths, and good bone fill of the defect.

CONCLUSION

Traditionally, endodontic-periodontal lesions, which were not responsive to initial therapy, would be given a questionable prognosis and be extracted. This case demonstrates that non-healing, peri-apical lesions may be cystic in nature and effectively managed utilizing a combined approach, with apicoectomy and GTR with EMD, to produce a stable outcome.

Influence of incision on periodontal parameters after apical surgery: a meta-analysis

INTRODUCTION

The aim of the present meta-analysis was to determine the effect of the different incision designs used in apical surgery on periodontal parameters.

METHODS

An electronic search in Cochrane Library, Pubmed (MEDLINE), and Scopus was conducted on April 2020. Two independent investigators included clinical trials and prospective cohort studies comparing the influence of different incision designs used in apical surgery on gingival recession, periodontal probing depth, and clinical attachment level. A pairwise and network meta-analysis was performed in order to meta-analyze the direct and the indirect comparisons among the incision designs.

RESULTS

Six articles were included for the qualitative and the quantitative syntheses, involving a total of 401 teeth (372 patients). The pairwise meta-analysis did not reveal statistically significant differences between the incision designs in any of the outcomes evaluated. However, to reduce the amount of buccal gingival recession, the papilla base incision presented the highest probabilities of being ranked the most effective incision (85.7%), followed by submarginal incision (50.0%) and intrasulcular incision (14.3%).

CONCLUSION

Regardless of the incision design used, the periodontal parameters did not statistically differ after apical surgery.

CLINICAL RELEVANCE

Periodontal parameters did not significantly change despite the incision used in apical surgery. However, based on the results of the present review, the papilla base incision seems to be the best option to reduce the amount of buccal gingival recession.

Apicoectomy of Perforated Root Canal Using Bioceramic Cement and Photodynamic Therapy

Root perforation is a common endodontic accident. Its management depends mainly on root canal disinfection and sealing the perforation area by preventing any communication with the periodontium to prevent recontamination. A patient was referred to treat root perforation due to a previous treatment of tooth #22. The diagnosis was symptomatic periapical periodontitis, and the treatment plan was to retreat the root canal of #22 and make a surgical intervention (apicoectomy) associated with antimicrobial photodynamic therapy as a complementary technique. Five mineral oxides (5MO) cement was used as a root-end filling material. The procedures were performed in two sessions and controlled in two visits (after 30 days and 12 months). A bone neoformation was observed at the periapical area of tooth #22. 5MO bioceramic cement was effective in inducing the repair of the periapical lesion and had the ability to seal the exposed periapical area of the tooth. Its success depended mainly on root canal and surgical site disinfection.

Root Canal Transportation after Root Canal Preparation with ProTaper Next, WaveOne Gold, and Twisted Files

Background: Root canal preparation during endodontic treatment may be associated with various complications, including a change in the original pathway of the root canal lumen. The aim of our study was to determine whether files of similar sizes that use various movement kinematics (rotary, reciprocal, adaptive motion) cause root canal transportation, and whether the differences between such systems are statistically significant. Methods: The degree of root canal transportation (DT) was calculated with the use of computed tomography scans for 3 groups of teeth (for each group: n = 20) in which the root canals were prepared using either rotary (ProTaper Next—PTN), reciprocal (WaveOne Gold—WOG), or adaptive movement (Twisted Files—TF) instruments. Results: For rotary ProTaper Next instruments, the mean value of the DT index was 0.0795 (SD = 0.0179) for 3 mm from the apex, 0.09 (SD = 0.0262) for 6 mm from the apex, and 0.106 (SD = 0.0221) for 9 mm from the apex. For reciprocal WaveOne Gold Primary instruments, the mean value of the DT index was 0.0355 (SD = 0.015) for 3 mm from the apex, 0.061 (SD = 0.02) for 6 mm from the apex, and 0.08 (SD = 0.25) for 9 mm from the apex. For Twisted Files, the mean value of the DT index was 0.05 (SD = 0.03) for 3 mm from the apex, 0.092 (SD = 0.17) for 6 mm from the apex, and 0.08 (SD = 0.02) for 9 mm from the apex. Conclusions: The use of PTN, WOG, and TF files resulted in root canal transportation to a different degree. The use of rotary PTN files produced the most transported preparation, whereas the use of WOG files produced the conservative root canal preparation that allowed the retention of the original shape of the root canal.

German Dentists' Preferences for the Treatment of Apical Periodontitis: A Cross-Sectional Survey

Currently, there is no standard treatment protocol for apical periodontitis (AP). Thus, restorable teeth might get extracted and replaced prosthetically. This study evaluated German dentists’ preferred AP treatment decisions and the influencing factors for selecting tooth retention by initial/repeated surgical/non-surgical root-canal treatment (RCT) or extraction with/without prosthetic replacement. Through an online-survey, participants (n = 260) rated different treatment options for four case scenarios with AP in anterior/posterior teeth without/with previous RCT. Statistical analysis included the Friedman test for intra-case comparisons and Chi-squared test for factor-associations (p ≤ 0.05). Tooth retention using initial/repeated RCT was ranked first in all scenarios and rated as (very) appropriate by most participants, while implant-supported crowns (ISC) and apicoectomy had the second ratings. ISC were preferred more on posterior teeth or previous root-canal-treated teeth. Rating levels of treatment options displayed significant differences for all case scenarios. Posterior tooth retention by RCT demonstrated a significant association with work experience. Tooth retention with previous RCT displayed a significant correlation with dentists’ privately insured patients. Most dentists preferred tooth preserving with initial/repeated RCT, while others selected non-evidence-based choices. This reflects a lack of consensus of AP treatment decisions in Germany. Fixed treatment guidelines and further evaluation of treatment–decision-correlated factors are recommended for correct treatment planning.

Prospects of Advanced Therapy Medicinal Products-Based Therapies in Regenerative Dentistry: Current Status, Comparison with Global Trends in Medicine, and Future Perspectives

INTRODUCTION

Regenerative medicine offers innovative approaches to restore damaged tissues on the basis of tissue engineering (TE). Although research on advanced therapy medicinal products (ATMPs) has been very active in recent years, the number of licensed products remains surprisingly low and restricted to the treatment of severe, incurable diseases.

METHODS

This paper provides a critical review of current literature on the regulatory, clinical, and commercial status of ATMP-based therapies in the EU and worldwide and the hurdles to overcome for their broader application in Regenerative Dentistry.

RESULTS

Competent authorities have focused on developing regulatory pathways to address unmet patient needs. Oncology represents the dominating field, followed by cardiovascular, musculoskeletal, neurodegenerative, immunologic, and inherited diseases. Yet, the status remains in early development, and scientific, regulatory, and cost-effectiveness issues impose considerable hurdles toward marketing authorization, technology adoption, and patient accessibility. In this context, although regenerative dentistry has achieved breakthrough innovations in TE of several dental/oral tissues in preclinical models, it has hardly harnessed research progress to integrate innovative regenerative treatments into clinical practice.

CONCLUSION

Global demographic changes, which demonstrate a steady increase of the aging population, highlight the societal need for the application of ATMP-based therapies in the treatment of noncommunicable diseases (NCDs). Although oral diseases, as an integral part of NCDs, are not life-threatening and largely preventable, they sustain high prevalence, with severe burden on economy and quality of life. In this perspective, the urgent request to ultimately translate draining research in dental TE conducted during the last decades into innovative treatments brought safely and cost-effectively into society at large still holds the stage. This review provides an overview of the regulatory, clinical, and commercial status of ATMP-based therapies in the European Union and worldwide and the hurdles to overcome for their broader application in regenerative dentistry.

B.P.F.C.® Bio-Plasma® with Pure Growth Factors (BioPlasma®) Used for the Treatment of a Persistent Great Periapical Lesion of an Endodontically Treated Tooth: A New Therapeutic Option

The aim of this case report was to evaluate the efficacy of a new platelet-rich plasma preparation and its regenerative capacity of bone periapical tissue for the treatment of a very compromised endodontic treated tooth, with a periapical lesion of 1.5 cm in diameter, using a pure platelet concentrate. This is made without the use of anticoagulant or any type of activator, e.g., bovine thrombin, calcium chloride. For this reason, it has been called "Pure"; it is the B.P.F.C.® Bio-Plasma® with Pure Growth Factors (BioPlasma®) designed and developed by Dr. Raffaello Viganò. The patient has read and signed a written consent form. The study protocol was approved by the Ethics Committee for Human Studies, University of Varese. X-ray at 2 and 6 months and 4 years after endodontic surgery demonstrated the success of the treatment.

Inspection of the Microbiota in Endodontic Lesions

The primary objective of endodontic therapy is to create a biologically acceptable environment within the root canal system that allows for the healing and maintenance of the health of the peri-radicular tissue. Bacteria are one of the main causes of pulp problems, and they have different methods of penetrating and invading the endodontic space such as through carious lesions, traumatic pulp exposures, and fractures. The types of bacteria found range from facultative anaerobes to aerobes, up to the most resistant species able to survive in nutrient-free environments; the bacterial species Enterococcus faecalis belongs to this last group. Enterococcus faecalis is considered one of the main causes of recurring apical periodontal lesions following endodontic treatment, with persistent lesions occurring even after re-treatment. The review presented in this paper was performed in accordance with the PRISMA protocol and covers articles from the related scientific literature that were sourced from PubMed, Scopus, and Google Scholar using the following terms as keywords: “endodontic treatment”, “endodontic bacteria”, “microbial endodontic”, and “endodontic failure”. Only the articles considered most relevant for the purposes of this paper were read in full and taken into consideration for the following review. The results show that Enterococcus faecalis, Actinomycetes, and Propionibacterium propionicum are the species most frequently involved in persistent radicular and extra-radicular infections.

Dentists and Dental Intern’s Preferences of Root Canal Treatment with Restoration Versus Extraction then Implant-Supported Crown Treatment Plan

Objectives:

The intent of this study was to evaluate and compare the preferences and treatment choices between dentists and dental interns with regard to the following different treatment modalities: Root Canal Treatment (RCT) with restoration versus extraction with Implant-Supported Crown (ISC) or surgical treatment in relation to the given case scenarios.

Methods:

The questionnaire was presented as an online survey with a case scenario. The total number of the respondents were 165. The four clinical case scenarios included an anterior and posterior tooth having apical periodontitis, with and without previous RCT. The treatment options were as follows: RCT with restoration, extraction then implant, and surgical treatment.

Results:

A total of 165 dentists and dental interns were included in this study. A hundred and three 62.4% respondents were dentists, 60; 36.3% were males and 105; 63.7% were females. Most of the respondents graduated from the College of Dentistry, Jazan University (93.9%). The highest percentages and numbers for Anterior Teeth (AT) were selected in related to the RCT and restorations in the four scenarios among gender, dentists, and interns, with no considerable differences. A high percentage of RCT and restoration option was recorded for Posterior Teeth (PT) with no previous restoration and around 50% for the same treatment modality to posterior teeth with previous restorations. For Future Planning Postgraduate Studies (FPPS), it was obvious that most of the selected specialties agreed with the RCT and restorations choice.

Conclusion:

All dentists and interns in both genders preferred RCT with restorations over extraction, and then ISC in the AT with and without previous RCTs. In the PT with no previous RCT, the participants agreed that RCT with restorations is superior to other choices. Among the FPPS, the respondents demonstrated an absolute agreement to RCT and restorations as a treatment of choice for different scenarios.

Clinical Significance:

Dentists should preserve the natural teeth by RCT with restoration as the first treatment choice followed by other choices. The nonsurgical approach should always be adopted as a routine measure in PA lesions of endodontic origin. Conservative orthograde endodontic therapy demonstrates favorable outcomes with a regular periodic review and assessment of the healing process of PA lesions.

Patients' self-report on post-retained restoration is more valuable than expected! Explorative analysis of an 11-year follow-up

Objective: Assessment of long-term clinical data regarding post-endodontic restorations is essential for the evaluation of different post-and-core concepts. The aim of the present study was to assess the diagnostic accuracy of patient self-reporting on post-endodontic restorations after 11 years of clinical service.Materials and methods: Twenty-nine patients (61 ± 15 years old) with endodontic glass-fibre and titanium post-endodontic restorations were examined within the 11-year follow-up of a randomized controlled trial. Restorations were assessed by self-reports during a telephone interview (one item), the completion of a four-item questionnaire and clinical and radiographic examination. A gold standard for restoration in situ or 'failure' was defined by clinical and radiographic examination. Diagnostic accuracy of patients' self-reports was evaluated by calculating the sensitivity, specificity, and positive (PPV) and negative predictive values (NPV).Results: After a mean observation time of 137 months (min/max: 125/154 months), 25 (86.2%) restorations were in situ and 4 (13.8%) failures were detected. Self-report during a telephone interview and the four-item questionnaire correctly identified all in situ restorations (specificity = both 100%, NPV = 92.6%/96.2%). Self-report during a telephone interview identified two out of four failures (sensitivity = 50%, PPV = 100%), and self-report on the four-item questionnaire identified three out of four failures (sensitivity = 75%, PPV = 100%).Conclusions: When the clinical examination is not feasible, patients' self-report shows valuable diagnostic potential in the identification of the post-endodontic failure.

Do endodontic retreatment techniques influence the fracture strength of endodontically treated teeth? A systematic review and meta-analysis

One of the major concerns about endodontically retreated teeth (ERT) is undoubtedly its loss of remnant structure, which could lead to consequently greater fracture risk. Therefore, the objective of this systematic review is to assess the influence of endodontic retreatment on the fracture strength of the dental tooth remnant. In vitro studies assessing the influence of mechanical retreatment on the mechanical properties (static or under fatigue) of restored teeth were searched in PubMed and SCOPUS databases. Three independent reviewers screened titles/abstracts of articles and the full-text of potentially eligible studies. The risk of bias was independently assessed by one researcher and verified by another two. Comparison between the mean load to fracture of teeth after endodontic treatment and after endodontic retreatment were estimated using pairwise random effects meta-analysis to calculate pooled mean differences. Three studies were included for the systematic review and 2 for the meta-analysis. The pooled effect indicated a statistical difference (Mean difference: -121.03 95%CI: -183.02, -59.05) between conditions favoring the endodontically treated teeth. However, the low number of studies combined with their heterogeneity made it difficult to prove such phenomenon. ERT might present lower fracture strength than endodontically treated teeth. However, more coherent laboratory tests may provide better evidence and quantitative parameters on how much reliability can be attributed to an endodontic retreatment, in addition to which technique can provide more predictable results in this conservative approach.

Tooth Survival after Surgical or Nonsurgical Endodontic Retreatment: Long-term Follow-up of a Randomized Clinical Trial

INTRODUCTION

The aim of the study was to determine long-term tooth survival after endodontic retreatment and whether the presence of intraradicular posts influences the outcome.

METHODS

Ninety-five teeth were randomly assigned to surgical or nonsurgical endodontic retreatment. Forty-seven teeth in 45 patients were treated by conventional endodontic surgery and 48 teeth (47 patients) by nonsurgical retreatment, including the removal of intraradicular posts in 37 (77%). The outcome was tooth survival; follow-up continued until the tooth had been extracted, at least 10 years had elapsed since retreatment, the patient declined further follow-up, or the patient died. The Fisher exact test was used to analyze differences between the groups.

RESULTS

The median follow-up time was 10.1 years (range, 0.0-15.6 years). The overall survival rate was 76%, with no significant differences in long-term tooth survival between retreatment methods or the presence of an intraradicular post. The reasons for tooth extraction were related to the retreatment method. Vertical root fractures were significantly more frequent in the nonsurgical group when retreatment included post removal (P = .036).

CONCLUSIONS

There was no significant difference in long-term tooth survival after surgical or nonsurgical retreatment. The presence of intraradicular posts did not affect long-term tooth survival, but for teeth with posts, those retreated nonsurgically were more frequently extracted because of vertical root fractures than those retreated surgically (P = .036). The major limitations of the study were a smaller sample size and the use of outmoded retreatment techniques.

Differentiation of periapical granulomas and cysts by using dental MRI: a pilot study

The purpose of this pilot study was to evaluate whether periapical granulomas can be differentiated from periapical cysts in vivo by using dental magnetic resonance imaging (MRI). Prior to apicoectomy, 11 patients with radiographically confirmed periapical lesions underwent dental MRI, including fat-saturated T2-weighted (T2wFS) images, non-contrast-enhanced T1-weighted images with and without fat saturation (T1w/T1wFS), and contrast-enhanced fat-saturated T1-weighted (T1wFS+C) images. Two independent observers performed structured image analysis of MRI datasets twice. A total of 15 diagnostic MRI criteria were evaluated, and histopathological results (6 granulomas and 5 cysts) were compared with MRI characteristics. Statistical analysis was performed using intraclass correlation coefficient (ICC), Cohen's kappa (κ), Mann-Whitney U-test and Fisher's exact test. Lesion identification and consecutive structured image analysis was possible on T2wFS and T1wFS+C MRI images. A high reproducibility was shown for MRI measurements of the maximum lesion diameter (intraobserver ICC = 0.996/0.998; interobserver ICC = 0.997), for the "peripheral rim" thickness (intraobserver ICC = 0.988/0.984; interobserver ICC = 0.970), and for all non-quantitative MRI criteria (intraobserver-κ = 0.990/0.995; interobserver-κ = 0.988). In accordance with histopathological results, six MRI criteria allowed for a clear differentiation between cysts and granulomas: (1) outer margin of lesion, (2) texture of "peripheral rim" in T1wFS+C, (3) texture of "lesion center" in T2wFS, (4) surrounding tissue involvement in T2wFS, (5) surrounding tissue involvement in T1wFS+C and (6) maximum "peripheral rim" thickness (all: P < 0.05). In conclusion, this pilot study indicates that radiation-free dental MRI enables a reliable differentiation between periapical cysts and granulomas in vivo. Thus, MRI may substantially improve treatment strategies and help to avoid unnecessary surgery in apical periodontitis.

Micro-computed tomography-based anatomical study of the branch canals in mandibular anterior teeth in a Chinese population

OBJECTIVES

To analyze the incidence and distribution of branch canals in mandibular anterior teeth.

MATERIALS AND METHODS

Three hundred mandibular anterior teeth, comprising 100 central incisors, 100 lateral incisors, and 100 canines, were scanned using a micro-computed tomography (micro-CT) system. Three-dimensional (3-D) visualization reconstruction of the root canal system and its branch canals was performed on each specimen. Data regarding the number of branch canals, the distance from the anatomical apex to the branch canal, and the orientation of each branch orifice were collected and analyzed.

RESULTS

One hundred and fifty-three primary branch canals and 35 secondary branch canals were detected in the specimens overall. The incidence of branch canals in mandibular anterior teeth was 34%, with the highest incidence (50%) exhibited in mandibular canines, followed by lateral incisors (29%). Of the 153 primary branch canals found in the mandibular anterior tooth samples investigated, 82.35% appeared within 3 mm of the apical region, while 71.90% were labial and lingual canals.

CONCLUSIONS

There was regularity in the distribution and orientation of branch canals in mandibular anterior teeth.

CLINICAL RELEVANCE

This knowledge may be employed as a guide in clinical endodontic therapy.

No clinical quantifiable benefits between non-surgical and surgical endodontic treatment

Data sourcesThe authors searched the following electronic databases: the Cochrane Oral Health Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline Ovid and Embase Ovid. The US National Registry of Clinical Trials (ClinicalTrials.gov) and the World Health Organisation (WHO) International Clinical Trials Registry Platform were searched for ongoing trials. There were no restrictions regarding language and publication date. The authors hand-searched the reference lists of the studies retrieved and key journals in the field of endodontics.Study selectionRandomised controlled trials (RCTs) involving people with periapical pathosis including comparison of surgical versus non-surgical treatment or different types of surgery. Outcome measures were healing of the periapical lesion assessed after one-year follow-up or longer, postoperative pain and discomfort and adverse effects such as tooth loss, mobility, soft tissue recession, abscess, infection, neurological damage or loss of root sealing material evaluated through radiographs.Data extraction and synthesisTwo review authors independently extracted data from the included studies and assessed their risk of bias. Study authors were contacted to obtain missing information. The authors combined results of trials assessing comparable outcomes using the fixed-effect model, with risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, and 95% confidence intervals (CIs) and they used generic inverse variance for split-mouth studies.ResultsThe review included 20 RCTs. Two trials at high risk of bias assessed surgery versus a non-surgical approach: root-end resection with root-end filling versus root canal retreatment. The other 18 trials evaluated different surgical protocols.There was no clear evidence of superiority in the surgical or non-surgical approach for healing at one-year follow-up (RR 1.15, 95% CI 0.97 to 1.35; two RCTs, 126 participants) or at four- or ten-year follow-up (one RCT, 82 to 95 participants), although the evidence is very low quality. More participants in the surgically treated group reported pain in the first week after treatment (RR 3.34, 95% CI 2.05 to 5.43; one RCT, 87 participants; low quality evidence).In terms of surgical protocols, there was some inconclusive evidence that ultrasonic devices for root-end preparation may improve healing one year after retreatment, when compared with the traditional bur (RR 1.14, 95%CI 1.00 to 1.30; one RCT, 290 participants; low quality evidence). There was evidence of better healing when root-ends were filled with MTA than when they were treated by smoothing of orthograde GP root filling, after one-year follow-up (RR 1.60, 95% CI 1.14 to 2.24; one RCT, 46 participants; low quality evidence).There was no evidence that using CBCT rather than radiography for preoperative evaluation was advantageous for healing (RR 1.02, 95% CI 0.70 to 1.47; one RCT, 39 participants; very low quality evidence), nor that any magnification device affected healing more than any other (loupes versus endoscope at one year: RR 1.05, 95% CI 0.92 to 1.20; microscope versus endoscope at two years: RR 1.01, 95% CI 0.89 to 1.15; one RCT, 70 participants, low quality evidence). There was no evidence that antibiotic prophylaxis reduced incidence of postoperative infection (RR 0.49, 95% CI 0.09 to 2.64; one RCT, 250 participants; low quality evidence).There was some evidence that using a papilla base incision (PBI) may be beneficial for preservation of the interdental papilla compared with complete papilla mobilisation (one RCT (split-mouth), 12 participants/24 sites; very low quality evidence). There was no evidence of less pain in the PBI group at day one post surgery (one RCT, 38 participants; very low quality evidence).There was evidence that adjunctive use of a gel of plasma rich in growth factors reduced postoperative pain compared with no grafting (measured on visual analogue scale: one day postoperative MD -51.60 mm, 95% CI -63.43 to -39.77; one RCT, 36 participants; low quality evidence). There was no evidence that use of low energy level laser therapy (LLLT) prevented postoperative pain (very low quality evidence).ConclusionsAvailable evidence does not provide clinicians with reliable guidelines for treating periapical lesions. Further research is necessary to understand the effects of surgical versus non-surgical approaches, as well as to determine which surgical procedures provide the best results for periapical lesion healing and postoperative quality of life. Future studies should use standardised techniques and success criteria, with precisely-defined outcomes and the participant as the unit of analysis.