Present Status and Future Directions - Surgical Endodontics

Comparing the accuracy and treatment time of a robotic and dynamic navigation system in osteotomy and root-end resection: An in vitro study

AIM

To compare the accuracy and treatment time of a robotic system (RS) and a dynamic navigation system (DNS) in osteotomy and root-end resection in an in vitro study.

METHODOLOGY

In this study, four identical mandibular models were created using three-dimensional (3D) printing, each model including 18 teeth. In the surgical procedures, teeth #35, #33, #32, #42, #43 and #45, along with the mesiobuccal roots of teeth #36 and #46, were specifically selected for operation on each model. Cone-beam computed tomography (CBCT) and intraoral scans were performed on all models. DentalNavi software was used to plan a drilling path and depth as well as design surgical accessories. In the RS, osteotomy and root-end resection were performed with robotic assistance, whereas in the DNS, these procedures were performed using dynamic navigation. Post-operative CBCT scans were obtained. Global platform deviation, global apex deviation, angular deflection, and time were compared to evaluate the accuracy and treatment time of the surgeries. The treatment time was defined as the registration time and drilling time. Statistical analyses were performed using the Shapiro-Wilk and independent sample t-test.

RESULTS

The global platform deviation, global apex deviation and angular deflection in the RS group were significantly smaller than those in the DNS group (p <.05). The registration time in the RS group was significantly longer than that in the DNS group (p <.001), whereas the drilling time was significantly shorter (p <.001). The overall surgical time was significantly longer in the RS group than in the DNS group (p <.001). Subgroup accuracy analysis revealed that in both the anterior and posterior tooth regions, the RS group exhibited significantly smaller apical and angular deviations than the DNS group (p <.001). Additionally, in both the anterior and posterior tooth subgroups, the total time for the DNS group was significantly shorter than that for the RS group in the anterior tooth area (p <.01).

CONCLUSIONS

RS showed higher accuracy and shorter drilling time in osteotomy and root-end resection compared to DNS. The RS holds promise as a reliable technological advancement in endodontic microsurgery. However, future endeavours should prioritize the reduction in registration time.

Application of artifact suppression algorithm of post-processing CBCT software in root canal filling materials

OBJECTIVES

Cone beam computed tomography (CBCT) is an imaging exam used increasingly in various fields of dentistry, and a greater number of endodontists are progressively gaining access to this technology. This study focused on applying an artifact suppression algorithm featured in CBCT software, and designed specifically to address artifacts related to root canal filling materials.

METHOD

The sample consisted of eighty-four mandibular molars, with mesial root canals endodontically treated by using the lateral condensation technique. Four root canal sealers were applied: G1 - Sealapex®, G2 - AH Plus®, G3 - Endofill®, and G4 - Bio-C Sealer. CBCT scans were taken using PreXion 3D Elite®. Initially, the diameter of the root canal filling (in the mesiodistal and buccolingual directions) was measured using a digital micrometer (control). Next, these diameters were reevaluated in the CBCT images using the blooming artifact reduction (BAR) tool of the e-Vol DX software. The Van der Waerden nonparametric analysis of variance was performed, followed by applying the Tukey test to the normalized data. The significance level was set at α = 5%.

RESULTS

There were no statistically significant differences (p>0.05) in the measurement of original root canal filling materials obtained by the micrometer versus the e-Vol DX software in the mesiodistal and buccolingual directions.

CONCLUSIONS

The tested software algorithm effectively suppressed artifacts resulting from obturation materials.

Autotransplantation of a Third Molar to Replace Compromised Molar With the Individual Three-Dimensional Printed Ultrasonic Osteotome: A Case Report

Tooth autotransplantation is widely used to replace congenitally missing teeth or teeth with irreversible damage. This case report presents a personalized ultrasonic osteotome that enables precise preparation, minimizes bone trauma, enhances the initial stability of the transplanted tooth, and contributes to a favorable prognosis. The procedure is as follows: a 25-year-old female patient presented with a porcelain-fused-to-metal crown on Tooth #19, which had detached due to severe decay, rendering the tooth unsalvageable. Tooth #32 exhibited mesial inclination, resulting in decay of Tooth #31. After presenting treatment plan, the patient provided informed consent by signing the necessary documentation to proceed with the autotransplantation of Tooth #32 to replace Tooth #19. Tooth #32 was extracted and immediately scanned chairside using a 3Shape scanner. A custom-designed, tooth root-shaped ultrasonic osteotome was fabricated using 3D printing technology to match the shape of Tooth #32. Tooth #19 was extracted using a minimally invasive technique. The alveolar socket of Tooth #19 was prepared using the customized 3D-printed ultrasonic osteotome and a computer-aided rapid prototyping resin model. Tooth #32 was then transplanted into the socket and secured with figure-eight suspension sutures. To prevent damage to bone cells and periodontal tissues from overheating during socket preparation, the ultrasonic osteotome was designed with a porous, water-cooled system, effectively addressing this issue. After 24 months of follow-up, the transplanted tooth met success criteria, with no signs of pathological radiolucency, root resorption, or pain in the donor tooth. The alveolar socket, prepared with the personalized ultrasonic osteotome, ensured an optimal fit for the donor tooth, maintaining its stability and minimizing postoperative complications. The use of 3D printing technology to create a personalized ultrasonic osteotome represents an innovative advancement in tooth transplantation, supporting the development of digital and minimally invasive techniques in this field.

From anatomy to surgery: Effectiveness of virtual simulation adjuvant to traditional methods in the preclinical training of apicoectomy

Anatomy forms the foundation for the training and execution of routine surgical procedures. However, a gap persists in effectively bridging anatomical knowledge with the confident performance of procedures. Virtual simulation (VS) techniques, based on experiential and situated learning theory, hold promise in addressing this challenge. Apicoectomy, a procedure involving root apex resection to preserve a tooth, requires a blend of regional and dental anatomy knowledge, making it an ideal model for assessing the effectiveness of VS. This prospective cohort study evaluated primarily the enhancement of incorporating VS training in the preclinical skill training of apicoectomy for undergraduate dental students, compared to relying solely on traditional methods. VS training includes the simulated dissection process, patient examination, and apicoectomy based on graphically synthesized virtual models. Secondly, the study investigated the influence of exposure to VS training on students' confidence and satisfaction. The training was divided into three progressive levels aligned with students' cognitive processes, employing Miller's competence learning framework. Participants were categorized into the control group (CG) (n = 214) and VS training group (VSTG) (n = 220) based on their classes. The results demonstrated that VSTG showed significantly greater training enhancement (VSTG: 7.14 ± 1.74; CG: 6.57 ± 2.02, p = 0.002) and higher confidence levels (VSTG: 2.94 ± 0.13; CG: 2.69 ± 0.13, p < 0.001), along with greater satisfaction with the training compared to the CG (VSTG: 3.70 ± 0.18; CG: 3.20 ± 0.17, p < 0.001). In conclusion, VS proves to be a valuable adjunct for enhancing procedural skill training in surgical procedures.

Endodontic treatment of a two-rooted mandibular first premolar with four root canals: a case report

Background

Mandibular first premolar has a complex and variable anatomy of the root canal system, which often leads to failure of endodontic treatment due to missing root canals. Identifying the complete structure of the root canal system to ensure that all root canals are perfectly cleared and filled becomes critical to the success of root canal therapy. This report introduced a unique case of endodontic treatment of a two-rooted mandibular first premolar in the buccolingual direction with a total of four canals.

Case presentation

An adult male patient with a lower left first premolar was diagnosed with acute apical periodontitis and treated with open pulp drainage in a general hospital. One day later, due to the complexity of the root canal structure, the patient was referred to our clinic for subsequent treatment. The tooth #34 was diagnosed with abnormal central cusp, apical periodontitis, and incomplete fracture through clinical and x-ray examinations. Cone-beam Computed Tomography (CBCT) results showed that the tooth #34 processed two roots with a buccolingual bifurcation and a total of 4 root canals: 1 lingual canal, 2 mesiobuccal canals, and 1 distobuccal canal. Notably, the buccal root presented a C-shaped configuration, and the mesiobuccal canals were of 2-1 type. The tooth was treated with microendodontics and crown restoration. One year after the treatment, the follow-up results showed that the tooth #34 was functioning normally without any abnormalities.

Conclusion

This report enhances our understanding of the anatomical variations in the root canal system of the mandibular first premolar and emphasizes the importance of CBCT in identifying anatomical variations within the root canal system. Clinicians must be aware of such changes in the mandibular first premolar during treatment to ensure a perfect treatment and better prognosis in clinical practice.

Outcome of Nonsurgical Root Canal Retreatment of Teeth with Persistent Apical Periodontitis Treated with Foraminal Enlargement and 2% Chlorhexidine Gel: A Retrospective Cohort Study

INTRODUCTION

Nonsurgical root canal retreatment (NS-RCRT) becomes necessary when primary endodontic procedures fail. This study evaluates the efficacy of NS-RCRT using 2% chlorhexidine gel and foraminal enlargement techniques, aiming to assess whether these approaches enhance periapical healing outcomes and success rates compared to traditional NS-RCRT techniques reported in the literature.

METHODS

This retrospective cohort study analyzed 120 teeth diagnosed with persistent apical periodontitis, from 80 patients who underwent NS-RCRT between January 2014 and December 2018 at a specialist's private practice. Data were collected following the Preferred Reporting Items for Observational Studies in Endodontics 2023 guidelines. Periapical healing was evaluated using digital periapical radiographs by three calibrated examiners. The outcome of the treatment was analyzed through descriptive statistics and bivariate analyses, including the Chi-Square and Fisher's Exact tests. Treatment outcomes were deemed successful if they showed complete or incomplete repair and unsuccessful if no repair was observed.

RESULTS

The average follow-up period was 30 months. Under loose criteria, 92.50% (n = 111) of the teeth were categorized as successful, and 7.5% (n = 9) as unsuccessful. Bivariate analysis indicated that the radiographic restoration of apical transportation was the only factor that significantly influenced the outcome.

CONCLUSIONS

NS-RCRT performed in a single visit using the foraminal enlargement technique and 2% chlorhexidine gel demonstrated high success rates and may be an effective alternative to tooth extraction. This method promoted periapical healing and could significantly improve NS-RCRT protocols. Further prospective studies are recommended to corroborate these findings.

Root-filling materials for endodontic surgery: biological and clinical aspects

The placement of root filling materials aims to prevent the occurrence of post-treatment apical periodontitis following completion of endodontic treatment. Materials should possess properties that will not permit bacterial invasion and infection, namely excellent sealing ability and/or antibacterial properties. In root-end filling procedures or repair of root perforations, the root filling materials are placed in a particularly challenging clinical environment, as they interface with a relatively large area with the periradicular tissues. The biological properties of these materials are therefore of significant importance. The current review discusses the most widely used materials for endodontic surgery (i.e., root-end filling and perforation repair), with particular focus on their biological characteristics, namely antibacterial properties and interactions with host tissue cells, together with clinical studies. Properties of amalgam, glass ionomer cements (GICs), resin systems, zinc oxide eugenol-based cements and hydraulic calcium silicate cements (HCSCs), together with representative and well-researched commercial materials in the context of their use in endodontic surgery are presented. While the use of HCSCs seems to offer several biological advantages, together with addressing issues with the initial formulation in the most recent versions, materials with different chemical compositions, such as zinc oxide eugenol-based cements, are still in use and appear to provide similar clinical success rates to HCSCs. Thus, the significance of the currently available materials on clinical outcomes remains unclear.

Scoping review on the genotoxicity of silver nanoparticles in endodontics: therapeutic saviors or genetic saboteurs?

Silver nanoparticles (AgNPs) have gained prominence in endodontics due to their exceptional antimicrobial properties. However, concerns regarding their genotoxic potential have prompted investigations into their safety profiles. This scoping review aims to consolidate current knowledge on the genotoxic effects of AgNPs in the field of endodontics. A thorough literature search across seven electronic databases was conducted using specific keywords. Inclusion criteria included experimental studies published in English from January 1960 to March 2024, addressing the genotoxicity of AgNPs in endodontic applications. Study selection and data extraction were conducted independently. The Quality Assessment Tool For In Vitro Studies (QUIN) tool was employed to evaluate the risk of bias in each study. 5 articles were selected, of which 3 were in vitro experimental designs, while the remaining were ex vivo studies. All were published between 2009 and 2021. AgNPs have been used as root canal irrigating solutions, pulp-capping materials, and root canal sealers. Most studies employed the comet assay for genotoxic evaluation. One study was found to have a low risk of bias, while others were categorized as having a medium risk. Mixed findings were noted on the genotoxic effects of AgNPs using various assays. The genotoxic potential of AgNPs somewhat poses concerns for endodontic practices. This review highlights the need for further research to develop safer alternatives and optimize their concentrations and exposure durations.

A Fluorescence-based Method to Reaccess Root Canals in Endodontically Treated Teeth: A Micro-Computed Tomography Tridimensional Assessment

INTRODUCTION

The aim of this study was to evaluate the volume of dentin removal and the volume of remnants of restorative material after the removal of an esthetic restorative coronal set and cervical barrier in endodontically treated mandibular molars with the aid of different magnification methods using 3-dimensional (3D) micro-computed tomographic (micro-CT) morphometric analysis.

METHODS

A sample of 30 mandibular first molars (N = 30) was used. All teeth were endodontically treated, and the specimens were initially scanned using micro-CT imaging and reconstructed. The molars were filled by a single-cone technique, and immediately the material at the initial 2-mm cervical level was removed. Cervical barriers were confected using ionomer glass cement with fluorescein 0.1%, filling the 2 mm at the cervical level of the canals and an additional 2 mm as the base. The coronal restoration set was performed using esthetic resin composites. A simulated tooth aging process was performed with 20,000 thermocycling cycles. The sample was distributed into the following 3 groups (n = 10) for the removal of the restoration set and cervical barrier with diamond burs based on the magnification aid: no magnification aid (naked eye), operative microscope aid, and REVEAL device (Design for Vision Inc, Bohemia, NY) aid. After removal, the final 3D micro-CT scanning and reconstruction were conducted with the same parameters as the initial scanning, and superposition of the final and initial scanning was performed. Morphometric analysis was conducted using CTAn software (Bruker microCT, Kontich, Belgium) to assess the volume of remnant restorative material (mm³), the volume of dentin removal (mm³), and the direction and site of dentin removal. Data were analyzed using 1-Way analysis of variance (P < .05).

RESULTS

The REVEAL group showed better results regarding the volume of remnant material (3.17 ± 1.65) and the percentage of dentin removal (2.56 ± 1.34). The microscope group showed no statistical difference compared with the REVEAL group regarding dentin removal (3.30 ± 1.48) and was statistically similar to the naked eye group in the volume of remnant material (9.63 ± 4.33). The naked eye group showed the worst results for the volume of remnant material (7.60 ± 2.68) and the percentage of dentin removal (6.60 ± 3.70).

CONCLUSIONS

The use of fluorescence associated with magnification was the method that presented the best results, with lower percentages of dentin removal and smaller volumes of remaining restorative material. This is an innovative technology in endodontics that shows potential to overcome the challenge of reaccessing root canals in the context of endodontic retreatment.

Comparison of Accuracy and Operation Time in Robotic, Dynamic, and Static-Assisted Endodontic Microsurgery: An In Vitro Study

INTRODUCTION

This study aimed to compare the accuracy and operation time (OT) of robotic-assisted endodontic microsurgery (RA-EMS), dynamic navigation-guided (DN-guided) EMS, and static navigation-guided (SN-guided) EMS.

METHODS

Seventy-two teeth from three sets of standardized jaw models (TrueTooth, DELendo, Santa Barbara, CA) randomly assigned into 3 groups underwent osteotomy and root-end resection. Preoperative plans and postoperative cone-beam computed tomography images were imported into an accuracy analysis system and aligned based on the anatomical structures to assess accuracy. The OT was recorded from the moment the foot pedal was pressed down until the bur reached the target depth. Statistical analyses were conducted using Kruskal-Wallis and Scheirer-Ray-Hare tests, with significance set at P < .05.

RESULTS

RA-EMS exhibited significantly higher accuracy than DN- and SN-guided EMS in terms of platform, angular, and resection angular deviations (P < .05). Additionally, RA-EMS exhibited significantly higher accuracy than DN-guided EMS in resection length deviation (P < .05). Significant differences were also observed in OTs between the 3 approaches, with SN-guided EMS showing the shortest OT, followed by RA-EMS and DN-guided EMS. Differences in jaw types within the DN-guided EMS group were observed in terms of angular deviation (P < .05).

CONCLUSIONS

All 3 treatment approaches demonstrated acceptable clinical accuracy and OT. RA-EMS exhibited superior accuracy, suggesting its potential application prospects in endodontics. Further high-quality clinical studies are warranted.

The learning curve of a dynamic navigation system used in endodontic apical surgery

Background/purpose

Quantitative in vitro research was conducted on the learning process of a dynamic navigation system. This study provides guidance for the promotion and application of dynamic navigation technology in the endodontic apical surgery field.

Materials and methods

Standardized models were designed and 3D printed to form the approach operation of endodontic apical surgery. 6 clinicians with no experience in dynamic navigation performed the operation. The distance deviation tolerance was set as 0.6 mm, and the angle deviation tolerance was set as 5°. Fifteen mm deep approach operation was completed using dynamic navigation. Each operator performed 10 consecutive exercises on the models. The positioning deviation and operation time of each operator for each practice were recorded. Based on this, the learning curve of the dynamic navigation of every operator was mapped. The learning difficulty of dynamic navigation was evaluated.

Results

The learning curves of all operators reached a stable level after the 7th practice, which can ensure that the distance and angle deviations are maintained within the deviation tolerances (0.6 mm, 5°).

Conclusion

Operators with no experience in dynamic navigation technology need practice to master dynamic navigation operations. For this navigation system, operators with no operational experience can master dynamic navigation operations after 7 exercises.

Endodontic and Surgical Management of Root Perforation Caused by Intermaxillary Fixation (IMF) Screw Placement: A Case Report

The use of fixation screws is a valuable tool in the clinical practice of oral and maxillofacial surgeries. One potential complication of screw placement for fracture fixation is root damage during surgery. In some cases, this damage can further lead to irreversible pulp damage, which requires endodontic and/or surgical intervention. The present report describes a case of iatrogenic root perforation during intermaxillary fixation (IMF) screw placement, leading to pulp necrosis. Despite the complication, the root damage was effectively managed through non-surgical root canal treatment using calcium silicate root filling material, followed by surgical apicectomy and retrograde fill. The patient was asymptomatic at a nine-month follow-up, and radiographic examinations showed signs of initial bone healing at the surgical site. After the successful management of the root perforation, the patient was referred to the prosthodontics department for the placement of the final restoration. It is important to understand the potential damage that may occur with screw-root contact and how it can be avoided or minimized. This report highlights the challenges and considerations in managing such cases and emphasizes the importance of using IMF screws with caution and the need for regular follow-ups in instances where tooth root damage has been confirmed.

Effect of different chelators on the push-out bond strength of hydraulic cements in retrograde obturation

Background

This study examined the effect of ethylenediaminetetraacetic acid (EDTA) and etidronic acid (HEDP) in retrograde cavities on the bond strength of MTA Angelus and NeoPutty.

Methods

Sixty-six teeth with single roots and canals were decoronated and enlarged up to F3 using the ProTaper Universal file system. After removing the apical 3 mm within the scope of endodontic surgery procedures, retrograde cavities were prepared with ultrasonic tips. The teeth were divided into three main groups according to the irrigation solution used: saline, 17% EDTA, and 9% HEDP. Following the irrigation of retrograde cavities, each main group was further divided into two subgroups in terms of using MTA Angelus and NeoPutty as retrograde filling materials. Bond strength values of hydraulic cements were measured by the push-out test. Fracture modes were examined under a stereo microscope. Two dentin sections from each group were examined under scanning electron microscopy (SEM) to observe dentinal tubules. Two-way ANOVA and post hoc Tukey tests were used to analyze the data.

Results

Irrigation solutions similarly affected the bond strength values of hydraulic cements (P=0.115). MTA Angelus showed significantly higher values than NeoPutty in all the solution groups (P=0.34). Adhesive and cohesive fracture modes were mostly observed in the MTA Angelus and NeoPutty groups, respectively.

Conclusion

EDTA, HEDP, and saline had a similar effect on the bond strength of hydraulic cements. The higher bond values of MTA Angelus compared to NeoPutty could support its safe use in endodontic surgery procedures.

Treatment of Retrograde Peri-Implantitis Originating From Apical Periodontitis of an Adjacent Tooth: A Clinical Case Letter

This report aims to present a treatment of retrograde peri-implantitis originating from apical periodontitis of an adjacent tooth in an 84-year-old male. Apical periodontitis of the maxillary left central incisor (#9) extended to the apex of the maxillary left lateral incisor implant (#10), which had been functioning for 16 years. Root canal treatment for #9 was performed, followed by root end surgery to treat the apical periodontitis, which showed a periapical radiolucency measured 1 cm in its greatest dimension. After the root end filling was placed, neither bone substitute materials nor barrier membranes were used to fill and cover the bony defect area. A 2-year postoperative radiograph confirmed the osseous healing around the apices of #9 and #10.

Advancements in guided surgical endodontics: A scoping review of case report and case series and research implications

This scoping review examined current case series and reports on guided surgical endodontic applications in order to provide a critical platform for future research. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews guidelines were followed. A search on PubMed and Scopus yielded 611 articles, with 17 case reports and 1 series meeting inclusion criteria. Overall, guided surgery addressed anatomical complexities, with 15 articles employing static protocols and 3 dynamic. Results showed minimal iatrogenic errors and reduced chair time, with no postoperative issues reported. Within the cases described, guided endodontic surgery exhibited satisfactory results in management of anatomical complex cases. Cost-effectiveness, the need for adequate follow-up, procedure's reproducibility and accuracy, and objective measurement of the reduction in operative times and iatrogenic errors are some of the limitations in the current reports that need to be considered for planning of future experimental and cohort studies.

The Use of Artificial Intelligence in Endodontics

Endodontics is the dental specialty foremost concerned with diseases of the pulp and periradicular tissues. Clinicians often face patients with varying symptoms, must critically assess radiographic images in 2 and 3 dimensions, derive complex diagnoses and decision making, and deliver sophisticated treatment. Paired with low intra- and interobserver agreement for radiographic interpretation and variations in treatment outcome resulting from nonstandardized clinical techniques, there exists an unmet need for support in the form of artificial intelligence (AI), providing automated biomedical image analysis, decision support, and assistance during treatment. In the past decade, there has been a steady increase in AI studies in endodontics but limited clinical application. This review focuses on critically assessing the recent advancements in endodontic AI research for clinical applications, including the detection and diagnosis of endodontic pathologies such as periapical lesions, fractures and resorptions, as well as clinical treatment outcome predictions. It discusses the benefits of AI-assisted diagnosis, treatment planning and execution, and future directions including augmented reality and robotics. It critically reviews the limitations and challenges imposed by the nature of endodontic data sets, AI transparency and generalization, and potential ethical dilemmas. In the near future, AI will significantly affect the everyday endodontic workflow, education, and continuous learning.

Advanced Material Strategy for Restoring Damaged Endodontically Treated Teeth: A Comprehensive Review

The restoration of endodontically treated teeth (ETT) remains a significant challenge in modern dentistry. These teeth often suffer from substantial structural damage due to both the original pathology and the invasive nature of endodontic procedures. Consequently, ETT are more susceptible to fractures compared to vital teeth, necessitating restorative strategies that can effectively restore both function and aesthetics while minimizing the risk of failure. In recent years, advances in adhesive dentistry and the development of high-strength ceramics have further expanded the restorative options for ETT. Bonded restorations have gained popularity as they preserve more tooth structure and enhance the overall strenght of the tooth-restoration complex. The choice of restorative material and technique is influenced by numerous factors, including the amount of remaining tooth structure, the functional requirements of the tooth, and the aesthetic demands of the patient. Despite the plethora of available materials and techniques, the optimal approach to restoring ETT remains a topic of ongoing research and debate. In this comprehensive review, the current state of and recent advances in restoring damaged endodontically treated teeth are explored. Numerous therapeutic options exist, involving a wide range of materials. This article aims to present the biomaterial advancements of the past decade and their applications, offering alternative approaches to treating damaged ETT with the goal of prolonging their retention on the dental arch and serving as a valuable resource for dental practitioners who face this issue daily.

An esthetic flap design for surgical endodontics in the anterior zone

OBJECTIVE

To describe an esthetic flap design for surgical endodontics in the anterior zone and to discuss the treatment outcome.

CLINICAL SIGNIFICANCE

Traditional flaps used in apical surgery in the anterior region are created with horizontal and vertical incisions. These incisions do not completely avoid scarring, and may sometimes cause esthetic defects. We describe an envelope flap with no vertical incision for apical surgery in anterior that mainly consists of oblique incision in interproximal papilla. The approach achieve rapid would healing while avoiding scar formation.

CONCLUSIONS

The present report describes successfully treated cases of surgical endodontics in the esthetic zone using an envelope flap that the author recommend in order to achieve better esthetic results.

Endodontic Microsurgery Outcomes over 10 Years and Associated Prognostic Factors: A Retrospective Cohort Study

INTRODUCTION

This retrospective cohort study aimed to evaluate long-term healing outcomes (10-17.5 years) after contemporary endodontic microsurgery (EMS) and identify the associated prognostic factors.

METHODS

Clinical and radiographic data of an EMS cohort (2006-2013) from the electronic database of the dental hospital were reviewed retrospectively by 2 independent examiners to determine their survival and healing outcomes, and potential prognostic factors were analyzed by Cox proportional hazards regression and logistic regression (α = 0.05).

RESULTS

Through strict inclusion and exclusion criteria and 721 EMS-treated teeth in the cohort, 309 (42.9%) were included (male = 35.0%; female = 65.0%; age = 45.83 ± 15.53 years) with a mean final follow-up of 152.26 ± 26.37 months (range, 120-211 months; median = 148 months). Clinical and radiographic assessments found an 80.5% 10-year survival rate with 63.4% of success. Collectively, tooth type, tooth mobility, preoperative lesion size, clinical crown-to-root ratio, and crown restorations at follow-up were significantly associated with long-term success and survival over 10 years.

CONCLUSIONS

The preoperative status and condition of the tooth including its alveolar bone support and adequate full-crown restorations may be relevant prognostic determinants of success and survival after EMS over time.

Finite element evaluation of dentin stress changes following different endodontic surgical approaches

The aim was to compare the effect of different endodontic surgical treatments on the stress distributions in dentin of a simulated first mandibular molar tooth using the finite element analysis method. Three surgical endodontic procedures (apical resection, root amputation, and hemisection) were simulated in a first mandibular molar. Biodentine or mineral-trioxide-aggregate was used to repair the surgery site in apical resection and root amputation models; the remaining root canal spaces were filled with gutta-percha. Access cavities were restored using resin composite. In hemisection model, root canal was filled with gutta-percha, and coronal restoration was finished with a monolithic zirconia crown. A sound tooth model was created as a control model. An oblique force of 300 N angled at 45° to the occlusal plane was simulated. Maximum von Mises stresses were evaluated in dentin near the surgery regions and the entire tooth. Apical resection/Biodentine and apical resection/mineral-trioxide-aggregate models generated maximum von Mises stresses of 39.001 MPa and 39.106 MPa, respectively. The recorded maximum von Mises stresses in root amputation models were 66.491 MPa for root amputation/Biodentine and 73.063 MPa for root amputation/mineral-trioxide-aggregate models. The highest maximum von Mises stress value among all models was observed in the hemisection model, measuring 138.87 MPa. Hemisection induced the highest von Mises stresses in dentin, followed by root amputation and apical resection. In apical resection, Biodentine and mineral-trioxide-aggregate did not show a significant difference in stress distribution. Biodentine in root amputation may lead to lower stresses compared to mineral-trioxide-aggregate.

A Comparative Evaluation of the Dissolving Abilities of Eucalyptus, Orange, and Castor Oils in Endodontic Retreatment Using Conventional and Rotary Techniques

INTRODUCTION

Endodontic retreatment is essential for periapical healing, involving the removal of inadequate fillings, thorough cleaning, and new filling application to prevent leakage. This study compares the dissolving abilities of Eucalyptus, Orange, and Castor oils in the re-treatment of resin-based endodontic fillings using conventional and rotary techniques.

METHODOLOGY

Thirty single-rooted human teeth were prepared and filled with gutta-percha and AH Plus sealer. They were divided into three groups (n=10) based on the solvent used (Eucalyptus, Orange, or Castor oil) and further subdivided based on the techniques used (conventional and rotary). Standardised re-treatment procedures were performed, and the amount of residual material was measured.

RESULTS

A significant difference (p<0.001) was found among the groups, indicating that both the type of solvent and the technique significantly affected the amount of residual material. The rotary technique generally left less residual material compared to the conventional technique for all solvents. Eucalyptus oil with the rotary technique showed the least residual material (mean = 5.8), while Castor oil with the conventional technique showed the most (mean = 10.2).

CONCLUSION

Eucalyptus oil, especially when used with rotary techniques, is highly effective in removing resin-based endodontic fillings, providing a viable and safer alternative to traditional solvents. The study underscores the importance of selecting appropriate solvents and techniques for successful endodontic re-treatment.

Systematic review and meta-analysis of root morphology and canal configuration of permanent premolars using cone-beam computed tomography

INTRODUCTION

The efficacy of root canal treatment is greatly impacted by a thorough understanding of root canal anatomy. This systematic review and meta-analysis aim to thoroughly investigate the root morphology and canal configuration (RMCC) of permanent premolars (PMs).

METHODOLOGY

A comprehensive analysis was conducted following the PRISMA guidelines. Literature exploration was carried out across four electronic databases (PubMed, Embase, Cochrane, and Web of Science). The risk of bias assessment was conducted for the included studies utilizing the Anatomical Quality Assessment (AQUA) tool. Data analysis was performed utilizing SPSS and RevMAN5.3.3. The meta-analysis was applied with a 95% confidence interval to calculate odds ratios (OR).

RESULTS

Among the 82 selected studies, 59 studies exhibited potential bias in domain one (objective(s) and subject characteristics), followed by domain three (methodology characterization). The majority of maxillary PM1s had either single root (46.7%) or double roots (51.9%), while three-rooted variants were uncommon (1.4%). Conversely, most other PMs exhibited a single root. In terms of canal configuration, maxillary PM1s predominantly featured double distinct canals (87.2%), with the majority of maxillary PM2s displaying either a single canal (51.4%) or double canals (48.3%). Mandibular PMs were primarily characterized by single canals, accounting for 78.3% of mandibular PM1s and 90.3% of mandibular PM2s. Subgroup analyses revealed higher incidences of single-rooted and single-canalled PMs among Asians compared to Caucasians. Additionally, women exhibited a higher incidence of single-rooted PMs, while men showed a greater frequency of double-rooted PMs.

CONCLUSIONS

The comprehensive analysis indicated that maxillary PM1s predominantly possess double roots and double canals, whereas maxillary PM2s and mandibular PMs were primarily characterized by single-rooted with a single canal. Notably, single root and single canal were more prevalent among women and Asian samples.

Endodontic Microsurgery With an Autonomous Robotic System: A Clinical Report

INTRODUCTION

Endodontic microsurgery (EMS) requires minimally invasive osteotomy and accurate root-end resection, which can be challenging in many instances. Evidence suggests that autonomous robotic systems can significantly enhance the precision of dental implantation. The aim of this case report is to introduce a novel EMS technique that employs robot-guided osteotomy and root resection procedures.

METHODS

A 59-year-old man was diagnosed with previously treated, symptomatic apical periodontitis in the mandibular left first molar. Patient data were used to integrate a digital model into preoperative planning software to design the surgical plan. The robotic system utilizes spatial alignment techniques for registration, guiding the robotic arm to autonomously perform a 3-mm osteotomy and root-end resection, based on the surgical plan. After completing the resection, the clinician confirmed the absence of cracks or root fractures and subsequently performed root-end preparation and filling under a microscope.

RESULTS

To the best of our knowledge, this case marks the first use of autonomous robotic assistance in EMS.

CONCLUSIONS

Utilizing an autonomous robotic system could enable precise apicoectomy in patients with intact cortical plates, thus facilitating successful EMS procedures. This has the potential to minimize errors caused by operator inexperience and mitigate the risks associated with excessive bone removal.

Simultaneous periodontal and endodontic surgery: report of four clinical cases

Case Description

Four cases of patients aged 41, 33, 43 and 68 years who presented periapical lesions and needed periodontal surgery for pre-prosthetic purposes.

Clinical Findings

The first case presented an intra-radicular retainer that was difficult to remove and likely to generate a root fracture. In addition, asymmetry of the gingival zenith was observed. The second case presented a complete crown at 16 with mesial marginal mismatch and subgingival margins distally. The third case presented a vestibular fistula with inflammation at the cervical level. The fourth case presented a vestibular fistula in the upper right lateral incisor. All patients showed apical lesions.

Treatment and Outcome

The first three cases received coronal lengthening and apical surgery in the same surgical procedure. In the fourth case, apical surgery was performed, and placement of implants 13 and 15 with a pontic of 14. During the clinical control and radiographs performed after the surgical procedures, bone filling of the lesion was found.

Clinical Relevance

Considering the results obtained, performing the periodontal and endodontic surgery procedures in a single surgical act is suggested. This reduces costs, travel, number of appointments, medication intake and post-surgical complications.

Outcome Assessment of Three Different Methods of Root-end Preparation and Filling Materials in Endodontic Surgery: A Comparative Clinical Prospective Study

Introduction

The technique of endodontic surgery had evolved tremendously in the recent years with introduction of new instruments and materials.

Aim

This study aims to compare the clinical outcome of endodontic microsurgery using three different techniques with three different root-end filling materials for 16 months.

Materials and Methods

A total of 45 maxillary incisors indicated for root-end surgery were selected for the study. They were enrolled into three groups, i.e. Group A (traditional [TRS]/heat burnished gutta-percha), Group B (concave [CON]/Retroplast), and Group C (cavity/DiaRoot BioAggregate), of 15 teeth each. The clinical and radiographic outcome was recorded at 1, 6, 12, and 16 months using various criteria.

Statistical Analysis

The data were analyzed by one-way analysis of variance and Tukey's post hoc test using SPSS V. 21 software (IBM Corp., Somers, NY, USA).

Results

All patients had uneventful healing at the final follow-up. Radiological intratime analysis concluded a highly high significant (P < 0.0001) decrease in the size of radiolucency between the three groups at the third recall visit. Intertime analysis recorded no significant decrease in radiolucency between Groups A and B, a significant decrease in B and C, and a highly significant decrease between Groups A and C at 12 months.

Conclusions

There was no significant difference in the clinical outcome after endodontic surgery when comparing TRS/heat burnished gutta-percha, CON/Retroplast, and cavity/DiaRoot BioAggregate techniques at 16 months. However, cavity/DiaRoot BioAggregate resulted in significantly rapid and predictable healing at 12 months.

Topography of root-end surface after freehand and three-dimensional-guided apicoectomy procedure: A scanning electron microscope study

Background

Dentinal microcracks formed during apical resection may lead to increased susceptibility to root fracture and improper sealing of apical preparation that may negatively influence the outcome of endodontic microsurgery.

Aims

This study was performed to analyze the root-end surface for dentinal microcracks using a scanning electron microscope (SEM) after resection with high-speed bur and trephine drill.

Materials and Methods

Thirty extracted single-rooted maxillary premolar teeth were selected and randomly distributed into two groups (n = 15). Working length was established using a #15 K-type file. Canals were prepared with a rotary Ni-Ti system to size 30/0.06 using endomotor, irrigated with 3% sodium hypochlorite, dried with paper points, and obturated with gutta-percha cones using a single-cone technique. All samples were mounted on preformed molds and poured using a mixture of sawdust and gypsum. In Group A; tungsten carbide bur was used to perform a freehand apicoectomy. In Group B; a trephine drill was used with a three-dimensional guide to perform 3 mm of root resection. Apicoectomy was performed in both groups under a dental operating microscope. Resected root ends were inspected for microcracks using SEM. The Shapiro-Wilk and Mann-Whitney U-test were used for statistical analysis.

Results

Microcracks were observed in all samples in both study groups. Trephine drill produced more microcracks on the resected root surface compared to the use of high-speed tungsten carbide bur with a statistically significant difference (P < 0.05).

Conclusions

The trephine drill used during targeted endodontic microsurgery produced more microcracks on the resected root dentine surface compared to the high-speed tungsten carbide bur used during freehand apicoectomy.

Dynamically guided transantral piezoelectric endodontic microsurgery: A case report with technical considerations

AIM

Endodontic microsurgery (EMS) of maxillary molars may represent a complex challenge to the clinician due to the location of the roots and the proximity of the maxillary sinus floor. This report aimed to describe the simultaneous use of a computer-assisted dynamic navigation (C-ADN) system and piezoelectric bony-window osteotomy for the transantral microsurgical approach of a maxillary left first molar with adequate root canal filling and symptomatic apical periodontitis.

SUMMARY

This case report highlights the importance of C-ADN to carry out a minimally invasive buccal surgical access to palatal roots affected by apical periodontitis and provides a practical example to help clinicians make treatment decisions based on the available evidence. Clinical and tomographic evaluations were performed before the surgical procedure and at 24-month follow-up. This case was treated using a C-ADN system fitted to a piezotome for the buccal approach of the buccal roots, maxillary sinus membrane lifting, and for transantral location, root-end resection, cavity preparation, and filling of the palatal root. The navigation system allowed to achieve an accurate apical canal terminus location and root-end filling of the three roots with a minimally invasive piezoelectric crypt approach. At the 24-month follow-up examination, the patient remains asymptomatic, with normal periapical structures, and regeneration of maxillary sinus walls. It was concluded that the combination of dynamic navigation with piezoelectric bony-window osteotomy offers enhanced accuracy, tissue preservation, diminished risk of iatrogenic complications, and could maximize success and survival rates in transantral EMS.

Root Canal Instrumentation: Current Trends and Future Perspectives

The evolution of root canal instrumentation techniques has significantly impacted the field of endodontics, enhancing both the efficiency and outcomes of treatments. This review outlines the transition from manual to mechanical and rotary instruments, highlighting the role of nickel-titanium (NiTi) alloys and smart technologies in advancing procedural precision and reducing patient discomfort. Key historical developments and technological innovations, such as digital imaging and navigation systems, are explored for their contributions to improved clinical outcomes and patient satisfaction. Additionally, the review addresses the challenges presented by the complex anatomy of the root canal system and the advent of current instrumentation techniques. The potential of emerging trends, including artificial intelligence and advances in materials science, is discussed in the context of future endodontic practices. Despite the progress, challenges related to using advanced instrumentation methods, ethical considerations, and the cost factor of new technologies persist. The present review underscores the ongoing need for research and development to further refine root canal instrumentation techniques, ensuring that advancements in endodontic care remain patient-centered and accessible.

The outcome of combined use of iRoot BP Plus and iRoot SP for root-end filling in endodontic microsurgery: a randomized controlled trial

OBJECTIVES

Root-end filling is important for the clinical outcome of endodontic microsurgery. Our previous study showed that combined application of iRoot BP Plus Root Repair Material (BP-RRM) and iRoot SP Injectable Root Canal Sealer (SP-RCS) in root-end filling exhibited better apical sealing as compared to the application of BP-RRM alone. The aim of this randomized controlled clinical trial was to evaluate the effect of the combined use of BP-RRM and SP-RCS on the prognosis of teeth with refractory periapical diseases after endodontic microsurgery.

MATERIALS AND METHODS

240 teeth with refractory periapical diseases scheduled for endodontic microsurgery were randomly divided into BP-RRM/SP-RCS group (n = 120) and BP-RRM group (n = 120). The patients were followed up at 3 months, 6 months, and 12 months after endodontic microsurgery. Pre- and post-operative clinical and radiographic examinations were performed to evaluate the treatment outcome. The 1-year success rate of endodontic microsurgery in BP-RRM/SP-RCS and BP-RRM groups was compared by Chi-square test. Factors that might impact the prognosis were further analyzed using Chi-square test or Fisher's exact test.

RESULTS

A total of 221 teeth completed the 12-month follow-up. The 1-year success rates of the BP-RRM/SP-RCS and BP-RRM groups were 94.5% (104/110) and 92.8% (103/111), respectively. The combined use of BP-RRM and SP-RCS achieved a clinical outcome comparable to BP-RRM alone (P = 0.784). Tooth type (P = 0.002), through-and-through/apico-marginal lesion (P = 0.049), periodontal status (P < 0.0001), and Kim's lesion classification (P < 0.0001) were critical factors associated with the 1-year success of endodontic microsurgery.

CONCLUSIONS

The combined use of BP-RRM and SP-RCS is a practicable method for root-end filling in endodontic microsurgery with a satisfactory 1-year clinical outcome.

CLINICAL RELEVANCE

The combined application of BP-RRM and SP-RCS in EMS is an effective root-end filling method with a satisfactory 1-year clinical outcome.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR2100052174).

Tooth intentional replantation from 1964 to 2023: A bibliometric analysis

BACKGROUND/AIM

There is no thorough overview of intentional tooth replantation techniques. We performed a bibliometric analysis of the development of intentional tooth replantation.

MATERIALS AND METHODS

A comprehensive search of the Web of Science and SCOPUS databases was conducted in February 2023. Original articles and reviews of human studies with "intentional replantation" or synonyms in the titles, abstracts, or keywords were included. A descriptive analysis of bibliographic data, co-occurrence analysis, and coupling of publications was performed. Multivariate analysis was used to explore the bibliometric parameters associated with the citation counts.

RESULTS

The study included 171 papers, which were co-authored by 500 individuals affiliated with 217 institutions from 28 countries/regions. The USA contributed the greatest number of publications, followed by China, and Japan. The USA had 694 citations, followed by Japan (210), and Turkey (210). The Journal of Endodontics and Dental Traumatology contributed the most citations. Five directions for future research were identified based on the coupling relationships of publications, including "managing vertical root fractures with adhesive resin using the intentional replantation technique," "intentional replantation for periodontally hopeless or endodontically compromised teeth," "intentional replantation for treating abnormalities of morphological development," "outcomes and prognosis factors of intentional replantation," and "treating root replacement resorption by intentional replantation." Multivariate analysis showed that the publication year, Journal Citation Reports ranking of journals, study design, and disease type were predictors of citation counts.

CONCLUSIONS

This bibliometric analysis provides a comprehensive description of the intentional replantation technique. The USA published the greatest volume of papers and generated the most citations. The Journal of Endodontics and Dental Traumatology are considered the most influential. The Journal Citation Reports journal ranking (Q1, Q2), study design (case reports, cohort studies), and disease type (crown root fractures) were associated with the citation counts.

Outcome of curcumin-based photodynamic therapy in endodontic microsurgery: A case report

INTRODUCTION

Persistent apical periodontitis after root canal treatment may require surgical retreatment when non-surgical options are ineffective or impractical due to anatomical challenges or iatrogenic errors. Endodontic microsurgery (EMS) is a precise technique that aims to overcome extraradicular biofilm and root morphology issues. Photodynamic therapy (PDT) is an emerging supplementary disinfection approach that utilizes a photosensitizer agent and light to eliminate microorganisms through oxidative reactions.

REPORT

A 60-year-old male with persistent apical periodontitis in a left maxillary first molar underwent non-surgical root canal retreatment followed by surgical reintervention due to anatomical complexities. During surgery, PDT was performed using a novel curcumin-based photosensitizer agent. After the procedure, the tooth was retrofilled with bioceramic cement, and photobiomodulation was applied to enhance tissue healing. One year post-surgery, the patient exhibited complete periradicular repair and remained asymptomatic.

DISCUSSION

EMS is considered a last resort to salvage an endodontically treated tooth and has shown moderate success rates. PDT has demonstrated promise in improving periapical healing and reducing microorganisms. In this case, curcumin, diluted with 2 % chlorhexidine gel, served as an effective photosensitizer agent with antimicrobial properties. Moreover, performing photobiomodulation aided in cell recovery and reduced postoperative discomfort.

CONCLUSION

The proposed EMS treatment protocol with PDT using curcumin yielded positive outcomes in this case report. Further randomized clinical trials are necessary to assess the efficacy of this approach in EMS. Additionally, further research on curcumin-based photosensitizer agents encapsulated in nanoparticles and enhanced antimicrobial agents is recommended to refine this treatment protocol for routine use.

A novel simplified approach for endodontic retrograde surgery in short single-rooted teeth

BACKGROUND

High technical thresholds, long operative times, and the need for expensive and specialized equipment impede the widespread adoption of endodontic microsurgery in many developing countries. This study aimed to compare the effects of a simplified, cost-effective, and time-efficient surgical approach involving orthograde obturation using biological ceramic material greater than 6 mm combined with apicoectomy for single-rooted teeth with short lengths with those of the conventional and current standard methods.

MATERIALS AND METHODS

Forty-five premolars equally categorized into three groups: conventional surgery group, standard surgery group, and modified surgery group. A µCT scan was used to calculate the volume of voids. A micro-leakage test and scanning electron microscope (SEM) were performed to assess the sealing effect. Additionally, four cases of chronic periapical periodontitis in the anterior region were selected, and the patients received either the modified approach or the standard surgery for endodontic microsurgery.

RESULTS

The volumes of voids in the apical 0-3 mm of the modified group and the standard group were comparable. The micro-leakage test and SEM examination demonstrated closely bonded fillings in the dentinal walls in both the modified surgery group and standard surgery group. The outcomes of the preliminary application of this modified procedure on patients were successful at the time of the follow-up cutoff.

CONCLUSIONS

The modified surgery group exhibited similar root canal filling and apical sealing abilities with the standard procedure for single-rooted teeth with short lengths (< 20 mm). The preliminary application of this modified surgical procedure achieved favorable results.

Resective and Regenerative Approach for an Unresolved Periapical Lesion: A Surgical Case Report With 24-Month Follow-Up

The pulp and the periodontium are inherently interconnected, both anatomically and functionally. Conditions affecting the periodontium and the pulp can create challenges in diagnosis, treatment strategizing, and predicting outcomes. This case report outlines the combination of resection and regeneration techniques utilizing mineral trioxide aggregate (MTA) and bone grafting to address a persistent periapical lesion in a maxillary premolar. The treatment led to the effective alleviation of the patient's symptoms and successful regeneration.

Clinical Outcome and Predictors of Endodontic Microsurgery Using Cone-beam Computed Tomography: A Retrospective Cohort Study

INTRODUCTION

The aim of this retrospective cohort study was to evaluate the clinical outcomes and identify the prognostic factors of endodontic microsurgery based on cone-beam computed tomographic (CBCT) scans.

METHODS

Patients who underwent endodontic microsurgery in teeth with asymptomatic apical periodontitis were included. The clinical outcomes were determined based on clinical and radiographic examinations after surgery 12-48 months. Radiographic healing was assessed on CBCT images by using the modified PENN 3-dimensional criteria and classified into 4 categories: complete, limited, uncertain, and unsatisfactory healing. Multivariate logistic regression was performed to detect outcome risk factors.

RESULTS

Of the 204 teeth in 173 invited patients, 148 teeth of 126 patients were examined at review. On CBCT images, 88 teeth (59.5%) showed complete healing, and 42 (28.4%) teeth showed limited healing. All these 130 teeth were asymptomatic and achieved a clinical success rate of 87.8%. Uncertain healing was observed in 9 teeth, one of which was symptomatic. The remaining 9 teeth were unsatisfactory healing on CBCT scans, including 6 teeth with clinical symptoms and 3 free. Lesion type and root-end filling quality were significant outcome predictors (P < .05). The risk of treatment failure for teeth with combined endodontic-periodontal lesions was 8.6 times higher than that for teeth with isolated endodontic lesions. Adequate root-end filling quality improved the probability of success by 5.3 times.

CONCLUSIONS

Based on CBCT data, an adequate performed endodontic microsurgery could have predictable success in teeth without periodontal involvement.

Antibacterial Activity of Root Repair Cements in Contact with Dentin-An Ex Vivo Study

This study assessed the antibacterial characteristics of the dentin/material interface and dentin surfaces exposed to experimental hydraulic calcium silicate cement (HCSC) with or without bioactive glass (BG) replacement (20% or 40%) or mixed with a silver nanoparticle (SNP) solution (1 or 2 mg/mL), and Biodentine, TotalFill BC RRM putty and Intermediate Restorative Material (IRM). Human root dentin segments with test materials were assessed at 1 or 28 days. In one series, the specimens were split to expose the dentin and material surfaces. A 24 h direct contact test was conducted against three-day established Enterococcus faecalis and Pseudomonas aeruginosa monospecies biofilms. In another series, the dentin/material interface of intact specimens was exposed to biofilm membranes for 3 days and the antibacterial activity was assessed via confocal microscopy. The interface was additionally characterised. All one-day material and dentin surfaces were antibacterial. Dentin surfaces exposed to HCSC with 40% BG-replacement, Biodentine and IRM had decreased antibacterial properties compared to those of the other cements. The HCSC mixed with a 2 mg/mL SNP solution had the highest antimicrobial effect in the confocal assay. The interfacial characteristics of HCSCs were similar. The test materials conferred antibacterial activity onto the adjacent dentin. The BG reduced the antibacterial effect of dentin exposed to HCSC; a 2 mg/mL SNP solution increased the antibacterial potential for longer interaction periods (three-day exposure).

Treatment of pulpal and apical disease: The European Society of Endodontology (ESE) S3-level clinical practice guideline

BACKGROUND

The ESE previously published quality guidelines for endodontic treatment in 2006; however, there have been significant changes since not only in clinical endodontics but also in consensus and guideline development processes. In the development of the inaugural S3-level clinical practice guidelines (CPG), a comprehensive systematic and methodologically robust guideline consultation process was followed in order to produce evidence-based recommendations for the management of patients presenting with pulpal and apical disease.

AIM

To develop an S3-level CPG for the treatment of pulpal and apical disease, focusing on diagnosis and the implementation of the treatment approaches required to manage patients presenting with pulpitis and apical periodontitis (AP) with the ultimate goal of preventing tooth loss.

METHODS

This S3-level CPG was developed by the ESE, with the assistance of independent methodological guidance provided by the Association of Scientific Medical Societies in Germany and utilizing the GRADE process. A robust, rigorous and transparent process included the analysis of relevant comparative research in 14 specifically commissioned systematic reviews, prior to evaluation of the quality and strength of evidence, the formulation of specific evidence and expert-based recommendations in a structured consensus process with leading endodontic experts and a broad base of external stakeholders.

RESULTS

The S3-level CPG for the treatment of pulpal and apical disease describes in a series of clinical recommendations the effectiveness of diagnosing pulpitis and AP, prior to investigating the effectiveness of endodontic treatments in managing those diseases. Therapeutic strategies include the effectiveness of deep caries management in cases with, and without, spontaneous pain and pulp exposure, vital versus nonvital teeth, the effectiveness of root canal instrumentation, irrigation, dressing, root canal filling materials and adjunct intracanal procedures in the management of AP. Prior to treatment planning, the critical importance of history and case evaluation, aseptic techniques, appropriate training and re-evaluations during and after treatment is stressed.

CONCLUSION

The first S3-level CPG in endodontics informs clinical practice, health systems, policymakers, other stakeholders and patients on the available and most effective treatments to manage patients with pulpitis and AP in order to preserve teeth over a patient's lifetime, according to the best comparative evidence currently available.

Augmented Reality-Guided Apicoectomy Based on Maxillofacial CBCT Scans

Implementation of augmented reality (AR) image guidance systems using preoperative cone beam computed tomography (CBCT) scans in apicoectomies promises to help surgeons overcome iatrogenic complications associated with this procedure. This study aims to evaluate the intraoperative feasibility and usability of HoloLens 2, an established AR image guidance device, in the context of apicoectomies. Three experienced surgeons carried out four AR-guided apicoectomies each on human cadaver head specimens. Preparation and operating times of each procedure, as well as the subjective usability of HoloLens for AR image guidance in apicoectomies using the System Usability Scale (SUS), were measured. In total, twelve AR-guided apicoectomies on six human cadaver head specimens were performed (n = 12). The average preparation time amounted to 162 (±34) s. The surgical procedure itself took on average 9 (±2) min. There was no statistically significant difference between the three surgeons. Quantification of the usability of HoloLens revealed a mean SUS score of 80.4 (±6.8), indicating an "excellent" usability level. In conclusion, this study implies the suitability, practicality, and simplicity of AR image guidance systems such as the HoloLens in apicoectomies and advocates their routine implementation.

Application of three-dimensional reconstruction technology in dentistry: a narrative review

BACKGROUND

Three-dimensional(3D) reconstruction technology is a method of transforming real goals into mathematical models consistent with computer logic expressions and has been widely used in dentistry, but the lack of review and summary leads to confusion and misinterpretation of information. The purpose of this review is to provide the first comprehensive link and scientific analysis of 3D reconstruction technology and dentistry to bridge the information bias between these two disciplines.

METHODS

The IEEE Xplore and PubMed databases were used for rigorous searches based on specific inclusion and exclusion criteria, supplemented by Google Academic as a complementary tool to retrieve all literature up to February 2023. We conducted a narrative review focusing on the empirical findings of the application of 3D reconstruction technology to dentistry.

RESULTS

We classify the technologies applied to dentistry according to their principles and summarize the different characteristics of each category, as well as the different application scenarios determined by these characteristics of each technique. In addition, we indicate their development prospects and worthy research directions in the field of dentistry, from individual techniques to the overall discipline of 3D reconstruction technology, respectively.

CONCLUSIONS

Researchers and clinicians should make different decisions on the choice of 3D reconstruction technology based on different objectives. The main trend in the future development of 3D reconstruction technology is the joint application of technology.

Management of Apico-marginal Defects With Endodontic Microsurgery and Guided Tissue Regeneration: A Report of Thirteen Cases

The loss of periodontal tissue support and vertical buccal bone loss in apico-marginal defects can often be mistaken for features indicative of vertical root fractures and this study reports thirteen cases with persistent symptomatic apical periodontitis, apico-marginal defects, and large periapical lesions that were managed with endodontic microsurgery in conjunction with bone grafts and barrier placements with a follow-up period of up to 9 years. At the recall sessions, all cases were asymptomatic with radiographical success with only 2 cases exhibiting residual apical radiolucency, but with evident reduction in the lesion size, indicative of healing. This study highlights the potential of utilizing endodontic microsurgery combined with guided tissue regeneration that proved effective in stimulating the regeneration of periodontal tissue in cases of apico-marginal defects that can lead to favourable long-term outcomes.

Management of Odontogenic Sinusitis: Results with Single-Step FESS and Dentoalveolar Surgery

OBJECTIVE

Odontogenic sinusitis (OS) is a well-known and important border of specialties in otorhinolaryngology and dentoalveolar surgery. Odontogenic sinusitis can develop due to iatrogenic harm or odontogenic infection. The gold standard diagnostic method is clinical and radiological-CBCT (cone beam computed tomography)-examination. The treatment of this condition requires collaboration between ENT and dentoalveolar surgery specialists and can be non-surgical or surgical based on staging. This paper aims to share the results of our clinical study whereby complex therapy was administered by a dentoalveolar surgeon and an otorhinolaryngologist in cooperation.

PATIENTS AND METHODS

We conducted a retrospective study comprising 111 OS patients who underwent complex therapy between 2016 and 2023 at Semmelweis University, Budapest, Hungary. All patients were treated with concurrent FESS (functional endoscopic sinus surgery) and dentoalveolar surgery. Follow-up was based on symptoms, clinical examination and CBCT imaging.

RESULTS

Of the 111 patients, 107 were successfully treated with concurrent FESS and dentoalveolar surgery, and only 4 had further symptoms following the complex therapy and needed retreatment.

CONCLUSIONS

The complex, single-session therapy involving FESS and oral surgery is an effective treatment method, which is less invasive and associated with fewer complications compared to previous interventions, such as the Luc-Caldwell procedure.

Glycyrrhizin Enhances the Proliferation of Diabetic Bone Marrow-derived Mesenchymal Stem Cells: A Potential Therapeutic Agent in Endodontic Surgery

AIM

This study aimed to evaluate the effects of glycyrrhizin, as a potential therapeutic agent in endodontic surgery, on the proliferation and viability of diabetic human bone marrow-derived mesenchymal stem cells (hBM-MSCs).

MATERIALS AND METHODS

Diabetic human bone marrow-derived mesenchymal stem cells (hBM-MSCs) were isolated and characterized by flow cytometry. The cells were treated with different concentrations of Glycyrrhizin (Gly) (12.5, 25, 50, and 100 µg/mL) and 0.1% dimethyl sulfoxide (DMSO) as the control group. MTT assay was performed to evaluate the cell proliferation and viability after 24, 48, and 72 hours of the cell treatment with Gly. The optical density (OD) was measured at 570 nm. Each assay was repeated three times. The corrected OD and cell viability were determined. ANOVA followed by the Bonferroni post hoc test evaluated the statistical significance at p < 0.05.

RESULTS

Flow cytometric analysis of the isolated cells showed positive expression of mesenchymal markers (CD105 and CD90) and negative expression of hematopoietic markers (CD34 and CD14). After 24 and 48 hours of cell treatment, Gly in 100 µg/mL concentration significantly decreased the diabetic hBM-MSC proliferation as compared with the control (p < 0.05). Gly in 12.5-50 µg/mL concentrations significantly increased the cell proliferation after 72 hours of treatment as compared with the control (p < 0.05). The diabetic hBM-MSC proliferation and viability at 12.5-50 µg/mL concentrations were significantly greater than that at 100 µg/mL concentration (p < 0.05).

CONCLUSION

Under the present study conditions, Gly (in 12.5-50 µg/mL concentrations) did not show cytotoxicity to diabetic hBM-MSCs and enhanced their proliferation. Gly may represent a potential therapeutic agent in endodontic surgery in diabetic patients.

CLINICAL SIGNIFICANCE

Preclinical assessment of Gly effects on diabetic hBM-MSCs is important for determining its effective concentration range, anticipating its therapeutic potential, and designing future in vivo studies.

Analysis of the Accuracy of a Dynamic Navigation System in Endodontic Microsurgery: A Prospective Case Series Study: Accuracy of DNS in EMS

OBJECTIVES

To evaluate the accuracy of a dynamic navigation system (DNS) for guided osteotomy and root-end resection during endodontic microsurgery (EMS) and assess its prognosis.

METHODS

Nine patients who met inclusion criteria underwent DNS-guided EMS. Osteotomy and root-end resection were performed with assistance of DNS (DHC-ENDO1, DCARER Medical Technology, Suzhou, China). The preoperative virtually planned path and postoperative cone-beam computed tomography images were superimposed using DNS software. Accuracy was assessed based on deviations in the platform, apex, and angle of the osteotomy, as well as in the length and angle of the root-end resection. Follow-up evaluations were performed after at least a year postoperatively.

RESULTS

Among the nine patients (11 teeth with 12 roots), the mean platform, apex, and angular deviation of the osteotomy were 1.05 mm, 1.2 mm, and 6.24°, respectively. The mean length and angle deviation of the root-end resection were 0.46 mm and 4.9°, respectively. Significant differences were observed according to tooth position. The platform and apex deviated significantly less in the posterior than in the anterior teeth (p < .05). No significant differences were observed according to arch type, side, and depth of the surgical path (p > .05). Eight patients were evaluated after at least a year postoperatively; clinical and radiographic evaluation revealed a 90% success rate (9/10 teeth).

CONCLUSIONS

This study demonstrated high accuracy of DNS in EMS. Furthermore, DNS-guided EMS had a success rate similar to that of freehand EMS over a short-term follow-up. Further study with a larger sample size is necessary.

CLINICAL SIGNIFICANCE

The present novel DNS technology is a viable method for guided osteotomy and root-end resection in EMS.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2100042312.

Predicting case difficulty in endodontic microsurgery using machine learning algorithms

OBJECTIVES

The study aimed to develop and validate machine learning models for case difficulty prediction in endodontic microsurgery, assisting clinicians in preoperative analysis.

METHODS

The cone-beam computed tomographic images were collected from 261 patients with 341 teeth and used for radiographic examination and measurement. Through linear regression (LR), support vector regression (SVR), and extreme gradient boosting (XGBoost) algorithms, four models were established according to different loss functions, including the L1-loss LR model, L2-loss LR model, SVR model and XGBoost model. Five-fold cross-validation was applied in model training and validation. Explained variance score (EVS), coefficient of determination (R²), mean absolute error (MAE), mean squared error (MSE) and median absolute error (MedAE) were calculated to evaluate the prediction performance.

RESULTS

The MAE, MSE and MedAE values ​​of the XGBoost model were the lowest, which were 0.1010, 0.0391 and 0.0235, respectively. The EVS and R² values ​​of the XGBoost model were the highest, which were 0.7885 and 0.7967, respectively. The factors used to predict the case difficulty in endodontic microsurgery were ordered according to their relative importance, including lesion size, the distance between apex and adjacent important anatomical structures, root filling density, root apex diameter, root resorption, tooth type, tooth length, root filling length, root canal curvature and the number of root canals.

CONCLUSIONS

The XGBoost model outperformed the LR and SVR models on all evaluation metrics, which can assist clinicians in preoperative analysis. The relative feature importance provides a reference to develop the scoring system for case difficulty assessment in endodontic microsurgery.

CLINICAL SIGNIFICANCE

Preoperative case assessment is a crucial step to identify potential risks and make referral decisions. Machine learning models for case difficulty prediction in endodontic microsurgery can assist clinicians in preoperative analysis efficiently and accurately.

Factors that influence the outcomes of surgical endodontic treatment

Surgical endodontic treatment encompasses a broad spectrum of procedures, amongst which root-end cavity preparation and filling, retrograde root canal treatment and through-and-through endodontic surgery, may be classified under the umbrella term 'Root-end surgery'. This narrative review considers the available data on periapical healing, soft tissue healing, tooth survival and oral health-related quality of life (OHRQoL), following root-end surgery and the factors that affect its outcomes. The pooled periapical healed rate for the studies published up to 2021 was 69% (95% CI: 65%, 73%) but increased to 76% (95% CI: 66%, 86%) when only data from the 2020's studies were analysed. The prognostic factors consistently reported for periapical healing have included: pre-operative periapical lesion with complete loss of buccal plate, quality of root-end preparation, remaining thickness of apical root dentine and restorative status. Soft tissue healing of the reflected flap was found to have a positive association with periapical healing. The survival rates following root-end surgery range from 48% to 93%, with failure of periapical healing associated with root and crown fracture, being the predominant reasons for tooth extraction. The factors influencing impact of root-end surgery on patients' quality of life could not be adequately evaluated due to design flaws in the available studies. In conclusion, if root canal treatment failure due to leakage through cracks, fractures or restoration margin are excluded, the remaining cases may represent localized residual infection and inflammation at the periapex that should be amenable to predictable management with the aid of modern root-end surgery.

Detecting Vertical Root Fractures Using Modified Methylene Blue Dye: A Preliminary In Vitro Study

Diagnostically, vertical root fractures (VRFs) can be a frustrating experience for the dentist. Misdiagnosis could result in significant time and effort losses involved in erroneously intervening endodontically and/or periodontally. Certainly, diagnosing VRFs is often very difficult, and diagnoses based on speculations have led to the extraction of many salvageable teeth. This study was conducted in the radiology unit of College of Dentistry, Prince Sattam bin Abdulaziz University, between December 2021 and June 2022 to evaluate the ability to detect VRFs following the use of a novel radio-opaque dye using periapical radiographs (PARs) and cone-beam computed tomography (CBCT). After carefully inducing VRFs on extracted, single-rooted, virgin premolars (n = 26), they were assigned to control (n = 2) and experimental groups (n = 24). The fracture site of the tooth in the control group received methylene blue dye, whereas the experimental group received a novel dye. Two differently angled PARs were obtained for all the teeth, followed by a CBCT image. Three blinded investigators participated in scoring a Likert scale form with a set of questions. Inter-/intra-examiner reliability showed excellent consistency using Cronbach's alpha test. The Z-test revealed CBCT and PAR to be equally adept at detecting VRFs, with the mean values showing no statistically significant differences. The extent of the VRFs and dye penetration were significantly better when angled radiographs and axial view CBCT were evaluated. Within the limitations of this study, the dye tested showed promising initial results as an aid in radiographically detecting VRFs. The use of such minimally invasive methods is critically needed for diagnosing and managing VRFs. However, further testing should be performed prior to its clinical use.

Effect of amniotic membrane and platelet-rich fibrin membrane on bone healing post endodontic surgery: An ultrasonographic, randomized controlled study

The use of membrane barriers and bone grafting materials in endodontic surgery promotes healing by regeneration rather than repair by scar tissue. Due to its valuable regenerative and therapeutic properties, the human amniotic membrane can support ideal periapical rehabilitation and promote better healing after surgery. The current trial aimed to evaluate the amniotic membrane's healing potential and compare it with platelet-rich fibrin using color doppler sonography. The current study is a randomized, double-blinded, parallel-group, single-center study. Thirty-four systematically healthy individuals requiring endodontic surgery who fulfilled all inclusion and exclusion criteria were selected and randomly placed in two groups. Surgical curettage of the bony lesion was performed and filled with hydroxyapatite graft. Amniotic membrane (Group 1) and platelet-rich fibrin (Group 2) were placed over the bony crypt, and the flap was sutured back. The lesion's surface area and vascularity were the parameters assessed with ultrasound and color doppler. and observations: The groups found a significant difference in mean vascularity at 1 month and mean vascularity change from baseline to 1 month (p < 0.05). Mean surface area had no statistically significant difference between the groups. However, in terms of the percentage change in surface area, a significant difference was found from baseline to 6 months (p < 0.05). Amniotic membrane was a significantly better promoter of angiogenesis than platelet-rich fibrin in the current trial. The osteogenic potential of both materials was similar. However, the clinical application, availability, and cost-effectiveness of amniotic membrane support it as a promising therapeutic alternative in clinical translation. Further large-scale trials and histologic studies are warranted.