A Novel Prefabricated Grid for Guided Endodontic Microsurgery

doi:10.1016/j.joen.2019.01.015

Journal of Endodontics

Volume 45, Issue 5, May 2019, Pages 606-610

https://doi.org/10.1016/j.joen.2019.01.015 Get rights and content

Highlights

•
A prefabricated grid was used to guide apical access during microsurgery.
•
The grid facilitates access to the apices of the roots for endodontic surgery.
•
The proposed method was more accurate than the nonguided method.

Abstract

Introduction

This study aimed to introduce a novel method using cone-beam computed tomographic (CBCT) imaging and prefabricated grids to guide apical access during endodontic microsurgery and to compare its accuracy with that of the nonguided method.

Methods

Forty-two roots from human cadaver jaws were selected. Twenty-one were randomly assigned to the experimental group (grid based) and their contralateral counterparts to the control group (nonguided). Preoperative CBCT images were used to design a drill path that intended to reach the palatal/lingual aspect of the roots without attempting to complete the osteotomy or to resect the entire root end. In the experimental group, prefabricated metal grids used during imaging and surgery acted as a reference in the design and drilling. Postoperative CBCT volumes were superimposed on the preoperative volumes, and the distances between the actual drill paths and the target points were measured. A dichotomized outcome of success versus failure was also recorded and compared. Statistical analysis was performed using the paired t test and Fisher exact test.

Results

The mean deviation of the drill paths from the target points was 0.66 mm ± 0.54 mm (mean ± standard deviation) for grid-based drilling and 1.92 mm ± 1.05 mm (mean ± standard deviation) for nonguided drilling (P < .001). Grid-based drilling was on average 1.27 mm (95% confidence interval, 0.81–1.72 mm) closer to the target point than nonguided drilling. The probability of successful drilling was also significantly higher with grids than without grids (P = .02).

Conclusions

The proposed method of guided osteotomy and root-end resection using prefabricated grids was more accurate than the nonguided method.

Section snippets

Root Selection

Roots from the maxillae and mandibles of 3 adult human cadavers were used. The dentate jaws were provided by the willed body program of Texas A&M College of Dentistry, Dallas, TX. Preoperative periapical radiographs were taken to confirm that none of the roots had periapical radiolucencies or previous endodontic surgeries. Inclusion criteria included mesiobuccal and distobuccal roots of maxillary first and second molars, mesial and distal roots of mandibular first and second molars, palatal

Results

The experimental drilling with grids deviated 0.66 mm ± 0.54 mm (mean ± SD) from the target point. In contrast, drilling in the control group deviated 1.92 mm ± 1.05 mm (mean ± SD) from the target point. These results were statistically different (P < .001). The drill paths in the experimental group were 1.27 mm (95% confidence interval [CI], 0.81–1.72 mm) closer to the preplanned target point than the drill paths in the control group.

Only 1 of 21 (5%) of the procedures with grids failed

Discussion

The benefits of accurately locating the apex during endodontic surgeries are numerous. It can minimize unnecessary surgical exploration and the possibility of iatrogenic damage to adjacent roots and nearby important anatomic structures such as the mental nerve and the maxillary sinus. It would also conserve more cortical bone and shorten the surgical time. The length of the access window (17) and the remaining height of the buccal bone plate (18) have been shown to affect the prognosis of

Acknowledgments

Dr Poorya Jalali is the lead inventor of the surgical grid. The grid has been designed and developed in collaboration with Webb Medical LLC, and a United States patent application has been filed for this surgical device and methods of use (USSN 16/134,506).

References (19)

S. Kim et al.
A randomized controlled study of mineral trioxide aggregate and super ethoxybenzoic acid as root-end filling materials in endodontic microsurgery: long-term outcomes
J Endod
(2016)
M. Torabinejad et al.
Tooth retention through endodontic microsurgery or tooth replacement using single implants: a systematic review of treatment outcomes
J Endod
(2015)
I. Tsesis et al.
Outcomes of surgical endodontic treatment performed by a modern technique: an updated meta-analysis of the literature
J Endod
(2013)
S. Kim et al.
Modern endodontic surgery concepts and practice: a review
J Endod
(2006)
I.B. Bender et al.
Intentional replantation of endodontically treated teeth
Oral Surg Oral Med Oral Pathol
(1993)
H.M. Pinsky et al.
Periapical surgery using CAD/CAM guidance: preclinical results
J Endod
(2007)
G.D. Strbac et al.
Guided modern endodontic surgery: a novel approach for guided osteotomy and root resection
J Endod
(2017)
S.-Y. Ahn et al.
Computer-aided design/computer-aided manufacturing–guided endodontic surgery: guided osteotomy and apex localization in a mandibular molar with a thick buccal bone plate
J Endod
(2018)
C.M. Giacomino et al.
Targeted endodontic microsurgery: a novel approach to anatomically challenging scenarios using 3-dimensional–printed guides and trephine burs—a report of 3 cases
J Endod
(2018)

There are more references available in the full text version of this article.

Cited by (17)

A Cadaver-based Comparison of Sleeve-guided Implant-drill and Dynamic Navigation Osteotomy and Root-end Resections
2023, Journal of Endodontics
This study compared the accuracy and efficiency of fully guided static and dynamic computer-assisted surgical navigation techniques for osteotomy and root-end resection (RER).
Fifty roots from cadaver heads were divided into two groups: fully guided static computer-assisted endodontic microsurgery (FG sCAEMS) and dynamic computer-assisted endodontic microsurgery (dCAEMS) (all, n = 25). Cone-beam computed tomography scans were taken pre and postoperatively. The osteotomy and RER were planned virtually in the preoperative cone-beam computed tomography scan and guided using 3D-printed surgical guides in the FG sCAEMS and 3D-dynamic navigation system in the dCAEMS. The 2D and 3D deviations and angular deflection were calculated. The osteotomy volume, resected root length, and resection angle were measured. The osteotomy and RER time and the number of procedural mishaps were recorded.
FG sCAEMS was as accurate as dCAEMS, with no difference in the 2D and 3D deviation values or angular deflection (P > .05). The osteotomy and RER time were shortened using FG sCAEMS (P < .05). The FG sCAEMS showed a greater number of incomplete RERs than dCAEMS. Osteotomy volume, RER angle, and root length resected were similar in both groups (P > .05). FG sCAEMS and dCAEMS were feasible for osteotomy and RER.
Within the limitations of this cadaver-based study, FG sCAEMS was as accurate as dCAEMS. Both FG sCAEMS and dCAEMS were time-efficient for osteotomy and RER.
Accuracy of digitally planned, guided apicoectomy with a conventional trephine and a custom-made endodontic trephine: An in vitro comparative study
2022, Journal of Stomatology, Oral and Maxillofacial Surgery
Citation Excerpt :
Guided trephine apicoectomy is an emerging endodontic surgical technique to enhance the accuracy of apicoectomy. While there is already some evidence to suggest that guided apicoectomy, in general, is indeed superior to the freehand approach in terms of accuracy, [20,22,31,32] but data are scarcely available on guided interventions performed with a trephine. In this study, we sought to compare the accuracy of digitally planned, guided apicoectomy performed with a commercially available and a custom-made trephine, in vitro.
Static guided trephine apicoectomy has been developed as a less invasive and more accurate alternative to conventional freehand apicoectomy with drills. Overpenetration is a frequent issue with this procedure, which deteriorates accuracy and raises safety concerns. A safety improvement to address this problem is presented.
Guided apicoectomies were performed in porcine mandibles with either a conventional bone trephine or a custom-made endo-trephine with built-in depth control. The deviation of the apical endpoint of the trephine from the digital surgical plan was analyzed. Overpenetration frequency was recorded.
Procedures performed with the custom trephine were significantly more accurate both along the x-axis and globally, but no significant difference was found for the y and z axes. Overpenetration frequency was 70% in the conventional trephine group versus 38% in the stop trephine group.
The results indicate that the lack of physical depth control can interfere with the accuracy (and safety) of these procedures to a significant extent, as visual cues (such as the depth markings on a conventional trephine) are insufficient to prevent overpenetration. Our results show that custom-made trephines with a built-in stop offer an optimal solution for this problem.
A Novel Simplified Workflow for Guided Endodontic Surgery in Mandibular Molars With a Thick Buccal Bone Plate: A Case Report
2022, Journal of Endodontics
Citation Excerpt :
Many authors18,19,21,22 reported the applications of these prototyped guides in different apical surgery situations. Specifically, regarding mandibular molars, different authors demonstrated the advantages of using a 3D-printed guide in patients with a thick buccal bone plate, allowing both precision and safety for accessing the apex15,23,24. For the first time, this study described a case in which an endodontic surgical guide was manufactured with a CBCT examination only, excluding the oral scanning step from the digital workflow.
One of the challenges in apical surgery in mandibular molars is the thick buccal cortical bone plate, which might lead to access errors, damage to neighboring teeth, and injury to healthy tissue. Surgical guide templates with 3-dimensional (3D) impressions have been suggested for use in such cases, allowing greater precision. Usually, this technique involves a cone-beam computed tomography (CBCT) examination related to a 3D oral scanning to generate surgical templates printed from 3D imaging data. This study reports a novel workflow possibility in which apical surgery is performed with the aid of a surgical guide planned only with CBCT, excluding the need for 3D oral scanning. A 32-year-old woman presented with asymptomatic apical periodontitis and external root resorption on the mesial root of tooth #19. A surgical template was planned using only the patient's CBCT scan to provide precise access to the lesion and remove a mandibular cortical bone block. The procedure was carried out with apicoectomy, root-end preparation, and retrograde filling, and the bone block was repositioned before suture. No postoperative complications were reported. After 1 year, the patient presented asymptomatic, and a CBCT scan confirmed bone healing. The current 3D-printed guides may be planned and printed through a novel simplified workflow with a CBCT scan only, which allows its application in apical surgery for precise apex and surgical site location.
PRESS and Piezo Microsurgery (Bony Lid): A 7-Year Evolution in a Residency Program—Part 2: PRESS-Defined Site Location
2022, Journal of Endodontics
Citation Excerpt :
A corollary disadvantage that has been cited is the damage to adjacent teeth because of the lid dimensions31. This may be true if the bony lid is attempted freehand, relying on the transfer of measurements from the scan or radiograph32. Parallax errors and disorientation of the landmarks in situ could have the potential to bias the incisions in the incorrect location.
Treatment of a failing endodontic procedure via microsurgical revision presents better outcomes due, in part, to the integration of the surgical operating microscope and cone-beam computed tomography into clinical practice. However, challenges still remain with respect to the operational locations and the techniques required to address them. Posterior sites, with substantial cortical plate thicknesses and sensitive anatomy, present the dichotomy of visualization versus postsurgical regeneration of bone. The bony lid technique bridges the gap between these 2 concepts, and the application of piezosurgery renders a precise and biocompatible osseous incision. The purpose of this article was to outline through case reports the progression of piezo-guided surgery in a resident setting.
The first 2 evolutions of the technique used a surgeon-defined method for site location. This third and final evolution uses a digital workflow to virtually plan the surgical procedure, integrating Standard Tessellation Language and Digital Imaging and Communication in Medicine files to create 3-dimensional guides with exacting resection locations, levels, and angles. Export of the virtually planned guide in postproduction generates the precision endodontic surgical stent to accurately define the site location and parameters of the procedure. All surgeries were executed using the piezosurgical method with increasing levels of guidance and precision throughout the evolution process.
Each step in the technique implementation enabled the resident to assimilate a new technique and skill set while maintaining bone architecture and minimizing volume loss postoperatively. The patient benefits were an increase in intraoperative safety and postoperative comfort. The resident benefits were accelerated regeneration timetables and increases in the confidence level of the resident and the number of scheduled posterior surgical procedures.
The progression from crude on-site measurements to elegant and precise surgical guides enabled the access and manipulations of difficult surgical sites without compromising visibility, postoperative osseous regeneration, or patient comfort.
Accuracy of root-end resection using a digital guide in endodontic surgery: An in vitro study
2021, Journal of Dental Sciences
Citation Excerpt :
The length and angle of root-end resection are controlled by the grooved guide track, and the depth of operation is controlled by a depth stopper. According to the results, the introduction of the digital guide in this study reduced length deviation (P < 0.01), which is similar to other studies.17,22,24 To our knowledge, this is the first study taking angle deviation as evaluating indicator.
It is difficult to achieve accurate root-end resection clinically. This in vitro study was conducted to evaluate the operation accuracy of a digital endodontic surgical guide.
56 extracted maxillary anterior teeth were prepared for endodontic surgical models. The models were randomly divided into 4 groups equally according to the guide (with guide/no guide) and the operator (experienced/inexperienced). Endodontic microsurgeries were performed on models in each group. The deviations in length and angle of the root-end resection were measured based on the optical scanning data of the pre- and postoperative teeth. The general linear model was performed to analyze the effect of a guide on root-end resection deviation.
Using a guide, the mean length deviation for experienced/inexperienced operators reduced from 0.99 mm (95% CI [confidence interval, CI], 0.66–1.33 mm)/1.18 mm (95% CI, 0.50–1.86 mm) to 0.31 mm (95% CI, 0.20–0.42 mm)/0.31 mm (95% CI, 0.24–0.37 mm). The mean angle deviation for experienced/inexperienced operators reduced from 16.74° (95% CI, 10.61–22.86°)/15.06° (95% CI, 9.19–20.94°) to 5.04° (95% CI, 3.31–6.77°)/6.79° (95% CI, 4.91–8.67°). The difference was significant between procedures performed with and without a guide (P < 0.01).
Application of the digital guide in vitro endodontic surgery could improve the accuracy of root-end resection.
Assessment of Cone-beam Computed Tomographic Referral Reasons and the Impact of Cone-beam Computed Tomographic Evaluation on Decision Treatment Planning Procedure in Endodontics
2020, Journal of Endodontics
Citation Excerpt :
This is also confirmed by the results of a recent questionnaire-based survey by Setzer et al13, who reported that surgical retreatment is a strong indication for CBCT examination. Several studies have shown the importance of CBCT usage for improved presurgical assessment19–22. Even in surgical cases that are considered a low degree of difficulty, CBCT imaging can aid significantly in the 3-dimensional orientation of the surgical field concerning the minimal invasion of the procedure and the accurate location of some difficult accessed lesions such as lateral lesions.
The aim of the present study was to assess the number of cone-beam computed tomographic (CBCT) referral cases from a private endodontic practice during a 1-year observation period and to investigate if preoperative use of CBCT imaging has an impact on the final diagnosis and decision treatment planning.
The data of the patients who attended a private endodontic office in Athens, Greece, seeking endodontic treatment from January 2018 to December 2018 were scanned to retrieve all the cases that were further referred for CBCT evaluation. Two qualified (University of Athens) and experienced (more than 10 years of daily practicing) endodontists referred the cases for CBCT imaging. All CBCT cases were evaluated to collect information about the number of cases, the reason for referral, the diagnosis before and after CBCT interpretation, and the treatment planning decision and management of each case. Descriptive statistics were used to describe the clinical characteristics of the study sample. Logistic regression was used to estimate the odds ratios and their 95% confidence intervals.
Of a total of 1029 patients (1269 teeth) referred for endodontic treatment, 86 patients were further referred for CBCT imaging (8.35% of the patients). A total of 104 teeth (8.2% of the teeth) were scanned. The most frequent reason for CBCT referral was surgical treatment planning. In 18 of 104 (17.3%) cases, there has been a change of the initial diagnosis after CBCT interpretation. Posterior and endodontically treated teeth without lesions presented 4.35 and 6.6 times times higher odds, respectively, of having a change in the initial diagnosis after CBCT evaluation.
A small percentage of patients referred for endodontic treatment or retreatment are further referred by specialists for CBCT imaging. CBCT scanning was considered necessary both for all surgical treatment planning cases and the evaluation of inflammatory resorptive defects.

View all citing articles on Scopus

View full text

Basic ResearchA Novel Prefabricated Grid for Guided Endodontic Microsurgery

Highlights

Abstract

Introduction

Methods

Results

Conclusions

Section snippets

Root Selection

Results

Discussion

Acknowledgments

J Endod

J Endod

J Endod

J Endod

Oral Surg Oral Med Oral Pathol

J Endod

J Endod

J Endod

J Endod

Basic Research
A Novel Prefabricated Grid for Guided Endodontic Microsurgery