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.

Robot-Assisted and Haptic-Guided Endodontic Surgery: A Case Report.

There has been a significant increase in robot-assisted dental procedures in the past decade, particularly in the area of robot-assisted implant placement. The objective of this case report was to assess the initial use of the Yomi Robot's assistance and haptic guidance during endodontic microsurgery. The robot was used during the osteotomy and root-end resection of the first and second upper left premolars. The report aims to inform clinicians of the initial implementation of this cutting-edge technology in endodontics and its potential to enhance endodontic microsurgery. The Yomi Robot was used in performing osteotomy and root-end resection during apical surgery in a patient presenting with symptomatic upper left first and second premolars. The treatment procedure was decided after clinical examination, chart data, and radiographic examinations, which showed periapical lesions on both premolars, taking into consideration the failed endodontic retreatment on the first premolar, the post and ceramic coronal restorations on both teeth, and the desire of the patient to save them. The Yomi Robot system provides auditory, visual, and physical guidance to clinicians during surgery while using a cone-beam computed tomography scan for precision planning with greater accuracy and minimized potential for human error. Further studies are needed to prepare a protocol for robotic-guided procedures in endodontics.

Comparison of the Accuracy and Efficiency of a 3-Dimensional Dynamic Navigation System for Osteotomy and Root-end Resection Performed by Novice and Experienced Endodontists.

INTRODUCTION: The aim of the study is to investigate whether the 3-dimensional dynamic navigation system (3D-DNS) can improve experienced endodontists' (EEs') and novice endodontists' (NEs') accuracy and efficiency in osteotomy and root-end resection (RER) and to verify that the 3D-DNS enables NEs to perform osteotomy and RER as accurately and efficiently as EEs. METHODS: Seventy-six roots in cadaver heads were randomly divided into 4 groups: 3D-DNS-NE, 3D-DNS-EE, freehanded (FH)-NE, and FH-EE (all, n = 19). Cone-beam computed tomography scans were taken preoperatively and postoperatively. Osteotomy and RER were planned virtually in the X-guided software (X-Nav Technologies, Lansdale). Accuracy was calculated by measuring the 2-dimensional and 3D virtual deviations and angular deflection using superimposing software (X-Nav technologies). Efficiency was determined by the time of operation and the number of mishaps. RESULTS: Accuracy deviations were significantly fewer in the 3D-DNS-EE group than those in the FH-EE group (P < .05). We found less 2-dimensional and 3D accuracy deviations comparing the 3D-DNS-NE group to the FH-NE group (P < .05). The time required for osteotomy and RER with the 3D-DNS was ∼ ½ of that required for the FH method for both EEs and NEs (P < .05). We found no difference in the number of mishaps between the 3D-DNS and FH groups for EEs and NEs (P > .05). CONCLUSIONS: The 3D-DNS improved EEs' and NEs' accuracy and efficiency in osteotomy and RER. The NEs were as efficient as the EEs using the 3D-DNS. Notably, the 3D-DNS improved the NEs' accuracy compared to the FH method, but the 3D-DNS did not enable the NEs to perform osteotomy and RER as accurately as the EEs.

Real-time 3-dimensional Dynamic Navigation System in Endodontic Microsurgery: A Cadaver Study.

INTRODUCTION: This study evaluated the accuracy and efficiency of the 3-dimensional dynamic navigation system (3D-DNS) to perform minimally invasive osteotomy (MIO) and root end resection (RER) in endodontic microsurgery (EMS) and investigated the viability of root end cavity preparation (RECP) and root end fill (REF) in MIO. METHODS: Forty-eight tooth roots were divided in cadaver heads into 2 groups: 3D-DNS (n = 24) and freehand (n = 24). Cone-beam computed tomographic scans were taken before and after surgery. First, virtual 3D-DNS accuracy was verified using 3 outcome measures: 2-dimensional and 3-dimensional virtual deviations and angular deflection. Second, the accuracy of 3D-DNS for performing MIO was investigated in 2 outcome measures: osteotomy size and volume. Third, the 3D-DNS accuracy was determined for RER in 3 outcomes: resected root length, root length after resection, and resection angle. The viability of RECP and REF was investigated and REF depth and volume measured as well, and procedural time and the number of mishaps were recorded. RESULTS: Two- and 3-dimensional virtual deviations and the angular deflection were lower in the 3D-DNS group than the freehand group (P < .05). Osteotomy height, length, and volume were all reduced when using 3D-DNS (P < .05). The resection angle was lower for 3D-DNS (P < .05). RECP and REF were completed in 100% of the roots. The REF depth achieved was ∼3 mm. Osteotomy time, RER time, and the total procedure time were all significantly shortened using 3D-DNS (P < .05). CONCLUSIONS: 3D-DNS enabled our surgeon to perform accurate and efficient EMS with minimally invasive osteotomy and RER. The surgeon was also able to conduct RECP with adequate REF in minimally invasive osteotomy performed using 3D-DNS guidance.

Root-end Surgery or Nonsurgical Retreatment: Are There Differences in Long-term Outcome?

INTRODUCTION: The decision of which modality of secondary endodontic treatment to perform is multifactorial and clinician dependent. The literature surrounding the long-term survival of nonsurgical retreatment compared with surgical retreatment remains equivocal and warrants further investigation. This 7-year retrospective study seeks to compare the outcome of nonsurgical retreatments with that of root-end surgeries performed on teeth without prior nonsurgical retreatments. METHODS: Insurance claims from 1021 teeth of 987 patients in the Delta Dental of Wisconsin database were analyzed from the years 2008-2017. Tooth survival was evaluated using Cox regression models, and the P value was set at .05. Survival time was considered from the time of completion of nonsurgical retreatment or root-end surgery to the time of an untoward event, which was defined as extraction after root-end surgery or extraction/root-end surgery after nonsurgical retreatment. Only procedures performed by endodontists were included in the analysis. RESULTS: The survival rate of teeth that received nonsurgical retreatment was 90% after 2 years, 86.8% after 4 years, and 85% after 6 years. The survival rate of teeth that received root-end surgery was 93.7% after 2 years, 90.5% after 4 years, and 88% after 6 years. No statistically significant difference was found in the survival of nonsurgical retreatment compared with root-end surgery. Likewise, no statistically significant difference was found within or between tooth types (anterior, premolar, or molar) when comparing nonsurgical retreatment with root-end surgery. CONCLUSIONS: The results of this study indicate that clinicians can choose either nonsurgical retreatment or root-end surgery after failed primary root canal therapy. Tooth location was not a determining factor in the survival rate after nonsurgical retreatment or root-end surgery.

A Clinical Evaluation of Cone-beam Computed Tomography: Implications for Endodontic Microsurgery.

INTRODUCTION: Cone-beam computed tomographic (CBCT) imaging is a valuable diagnostic tool for endodontics. Some studies report that CBCT images have limitations in representing the true clinical presentation. This prospective, in vivo study compared limited field of view (LFOV) CBCT measurements with clinical measurements made during endodontic surgery. METHODS: Eighty-seven subjects requiring endodontic surgery and LFOV CBCT acquisition of the surgical site were enrolled. Data collection involved clinicians answering standardized questions during the radiographic and surgical assessment. Intraoperatively, data were collected and photographically documented. Postoperatively, CBCT scans were evaluated by 3 calibrated, board-certified specialists: 2 endodontists and 1 oral and maxillofacial radiologist. The 2 subsets of data were compared through statistical analysis to quantify their relationship. RESULTS: The subjects included 65 maxillary and 29 mandibular teeth from 87 subjects: 25 women and 62 men with an average age of 42 years old. The CBCT evaluators correctly identified the presence or absence of buccal plate fenestrations with 91.0% accuracy (95% confidence interval, 83.1-96.0) with 89.4% sensitivity and 92.9% specificity. The area of fenestrations measured clinically (mean = 19.6 ± 33.4 mm2) was generally larger than the area measured by CBCT imaging (mean across CBCT evaluators = 12.2 ± 19.1 mm2). Fenestration size in the maxillary arch was more likely to be underestimated than in the mandibular arch (P < .0001). Vertical bone height was also underestimated when measured on CBCT imaging. CONCLUSIONS: Based on the findings of this study, LFOV CBCT imaging accurately identifies the presence or absence of buccal plate fenestrations, yet, when a fenestration is present, underestimates its area.

Root-end microsurgery using a premixed tricalcium silicate putty as root-end filling material: a prospective study.

OBJECTIVES: The purpose of this study was to assess the clinical and radiographic outcome of root-end microsurgery using a premixed fast-set calcium silicate putty as root-end filling material in human teeth. MATERIALS AND METHODS: This study included 50 teeth in 35 patients, whose ages ranged from 16 to 69 years. After clinical and radiographic examination, informed consent was obtained and one resident performed all surgical procedures using an endodontic microsurgical approach. A tricalcium silicate-based putty (TotalFil FS putty, FKG Dentair, La Chaux-de-Fonds, Switzerland) was used as a root-end filling material. Patients were recalled and treated teeth were examined clinically and radiographically at 3 months, 6 months, and 1 year postoperatively. The outcome was determined based on clinical and radiographic results. Radiographic healing was classified into 4 categories: complete, incomplete, uncertain, and unsatisfactory. Analysis of predictors was performed using the Pearson chi-square or Fisher's exact test. RESULTS: At the time of surgery, 3 teeth were diagnosed with cracks and were excluded from the study. The recall rates were 85% at 3 months, 100% at 6 months, and 95% at 1 year. One tooth failed at 3 months, 3 failed at 1 year, with a success rate of 93%. None of the predictors investigated had a significant influence on the outcome of microsurgery. CONCLUSIONS: Premixed fast-set tricalcium silicate putty is a suitable root-end filling material for use in endodontic microsurgery. CLINICAL RELEVANCE: Tricalcium silicate-based cements have shown promising biological properties as a root-end-filling material. Premixed and fast-set formulations achieved high success rates in clinical studies. TRIAL REGISTRATION: Clinicaltrials.gov registration number NCT03733938.

Accuracy and efficiency of guided root-end resection using a dynamic navigation system: a human cadaver study.

AIM: To determine and compare the accuracy and efficiency of a dynamic navigation system (DNS) with a freehand (FH) technique when conducting root-end resection in a human cadaver model. METHODOLOGY: Forty roots in cadaver heads were included and divided into two groups: DNS (n = 20) and FH (n = 20). Cone beam computed tomography (CBCT) scans of all teeth were taken. The drilling path and depth were planned virtually to using the X-guide software (X-Nav Technologies, Lansdale, PA, USA). Osteotomy and root-end resection were done under navigation in the DNS group, and freehand under the dental operating microscope in the FH group. Post-operative CBCTs were taken. Linear deviations, angular deflection, time of operation and number of mishaps were compared with determine the accuracy and efficiency. Shapiro-Wilk, one-way ANOVA and Fisher exact tests were used (P < 0.05). RESULTS: Linear deviations, angular deflection and operation time were significantly less in the DNS group (P < 0.05). The number of mishaps was not different between the two groups (P > 0.05). Subgroup analyses revealed that the distance of >5 mm from buccal cortical plate was significantly associated with lower accuracy, increased operation time and greater incidence of mishaps in the FH group (P < 0.05), but not in the DNS group. CONCLUSIONS: The dynamic navigation system was more accurate and more efficient in root-end resection in a cadaver model than the freehand technique. The distance of the roots from the buccal cortical plate had a significant negative impact on the accuracy and efficacy of the root-end resection procedure when using the freehand technique. The dynamic navigation system has the potential to be a safe and reliable technological addition to endodontic microsurgery.

Oral Fine Motor Control of Teeth Treated with Endodontic Microsurgery: A Single-Blinded Case-control Study.

INTRODUCTION: Periodontal mechanoreceptors (PMRs) are refined neural receptors present in abundance at the root apex and have a pivotal role in oral fine motor control. This case-control study aimed to evaluate the oral fine motor control of teeth treated with endodontic microsurgery (EMS) in comparison with the control teeth using a standardized behavioral biting task. METHODS: Fourteen eligible participants performed 5 trials of an oral fine motor control task that involved holding and splitting half of a peanut positioned on a force transducer with their EMS treated tooth and its contralateral control incisor tooth (28 teeth in total). The outcome variables were the mean food holding force, intra- and intertrial variability of the holding force, food splitting force, splitting duration, and the frequency of the stepwise splitting phase. The data were analyzed with parametric and nonparametric tests. RESULTS: The results showed no statistically significant differences in the holding force, inter- and intratrial variability of the holding force, splitting force, or splitting duration between the teeth treated with EMS and the control (P > .05). However, there was a significantly higher frequency of stepwise ramp increase during the splitting phase with EMS treated teeth compared with the control (48% and 37%, respectively; P < .05). CONCLUSIONS: EMS treated teeth showed similar force regulation and oral fine motor control as the contralateral control. The findings of this study suggest that EMS treatment does not perturb the sensory information of PMRs and maintains the force regulation and oral fine motor control of the teeth.

Technical note: surgical guide for computer-aided endodontic surgery.

INTRODUCTION: CBCT combined to intra-oral scansion are the means to build an endodontic surgical guide to perform an easier and safer access to the apex in endodontic micro-surgery. . METHODS: A 38-year-old woman presented chronic apical periodontitis, which involved the three roots of 16 that was treated by endodontic therapy several years ago elsewhere. The palatine channel was retreated, the mesio- and disto- buccal roots were instead treated with apicoectomy. A surgical template was printed by a 3D printer to obtain greater precision in the surgical access. CONCLUSIONS: Endodontic microsurgery has evolved over the years. New tools have been introduced to improve therapy, even if the basic principles have not changed. In fact, according to the literature, it is necessary to cut at least 3 mm of root to be sure of eliminating the anatomical variations and the accessory channels. Several Authors have devoted themselves to creating an endodontic surgical template, some in vitro and others in vivo. The present paper introduces a new method that allows a more conservative osteotomy and greater precision the surgical access. Further investigation are needed to test and improve the effectiveness of the treatment but this technique seems very promising because it is less invasive for the patient and simplifies the work for the dentist who can perform micro-surgery in an easier and faster way.