|Year : 2022 | Volume
| Issue : 1 | Page : 120-128
Management of pulp canal obliteration using static-guided endodontic technique: Case series
Afzal Ali1, Aasima Ishaq1, Payal Jain2, Sajid Ali3
1 Department of Conservative Dentistry and Endodontics, Pacific Dental College and Hospital, Udaipur, Rajasthan, India
2 Department of Conservative Dentistry and Endodontics, R R Dental College and Hospital, Udaipur, Rajasthan, India
3 Department of Conservative Dentistry and Endodontics, Dr. Ziauddin Ahmad Dental College and Hospital, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
|Date of Submission||24-Jun-2021|
|Date of Decision||31-Aug-2021|
|Date of Acceptance||31-Aug-2021|
|Date of Web Publication||8-Jan-2022|
Department of Conservative Dentistry and Endodontics, Pacific Dental College and Hospital, Airport Road, Udaipur, Rajasthan
Source of Support: None, Conflict of Interest: None
The present case series aims to describe the management of teeth with pulp canal obliteration (PCO) using the novel static-guided endodontic technique. Traumatic dental injury may result in partial or complete PCO, with and without periapical rarefaction and pose challenges during endodontic management. Three young adolescent patients presented to the department with a chief complaint of pain/discoloration/broken upper front teeth. The teeth were tender on percussion. Thermal and electrical pulp tests were negative for the concerned incisors. The periapical radiographic examinations revealed PCO and signs of periapical changes. A diagnosis of pulp necrosis; symptomatic apical periodontitis was established and nonsurgical endodontic treatment using the guided endodontic approach was planned with the patient consent. A cone-beam computed tomography (CBCT) scan and intraoral scanning were obtained using the special software to facilitate guided endodontics procedure. The surgical guides and a customized drill were fabricated. The drilling depth for the access to the calcified part was established using CBCT data, ensuring straight-line access. Conventional root canal treatment was completed. One-year follow-up examination revealed the absence of pain and periapical healing. In complicated cases with PCO and apical periodontitis, a CBCT and “Guided Endodontics” could be useful to save the tooth with minimal destruction of tooth structure and increase the chances of endodontic success.
Keywords: Canal obliteration, cone-beam computed tomography, endodontics, static-guided endodontics, three-dimensional printing
|How to cite this article:|
Ali A, Ishaq A, Jain P, Ali S. Management of pulp canal obliteration using static-guided endodontic technique: Case series. Saudi Endod J 2022;12:120-8
| Introduction|| |
Pulpal injury due to attrition, caries, previous restoration and trauma causes deposition of mineralized tissue into pulp cavity, resulting in its partial or complete obliteration, the process known as pulp canal obliteration (PCO).,
The prevalence of PCO after traumatic dental injuries varies from 3.7% to 40%.,,,, Pathophysiology of PCO has not been established to date, but Andreasen et al. hypothesized that it is associated with revascularization process after severe damage to the neurovascular supply of pulp. The development of PCO, however, relies on the type of injury and the patient's age when trauma occurs. More chances of PCO are seen with luxation and concussion injuries and immature roots with open apices. Clinically, tooth with PCO is asymptomatic, exhibit yellow discoloration of crown, and shows diminished or no response to pulp sensibility tests. Radiographically, PCO presents reduction in size of pulp chamber, root canal constrictions, with and without periapical rarefaction.
Such condition may predispose to pulpal necrosis in 1%–27% of the cases. In general, endodontic treatment in PCO teeth is required in two conditions; first, when internal bleaching is indicated to treat discoloration and second, when acute symptoms or apical lesions are present.,,,,
Despite the use of an operating microscope, locating and negotiating obliterated root canals can be a lengthy and challenging procedure. In addition, it may result in iatrogenic errors during access cavity preparation, including root perforation and file separation during root canal shaping.
Recently, guided endodontic technique has shown favorable outcome in the management of tooth with calcifications and tooth anomalies. It can be static, where stereolithographic templates were used to perform the procedure. However, dynamic navigation allows shorter surgical instrumentation, avoids the fabrication of a stereolithographic template but the initial cost of device is high. The “Guided Endodontics” approach shortens the chair side time and can reduce the chances of iatrogenic error.
With this innovative technique, a digitally scanned impression is acquired and is superimposed onto the data accumulated by cone-beam computed tomography (CBCT) software. A digital pathway for the drill is created, and a surgical template is orchestrated to access through the PCO utilizing computer-availed designing software. Conclusively, by utilizing a 3D printer, this surgical guide is printed.,
Numerous recent case reports,,, illustrate the successful implementation of this approach in endodontic therapy due to its safety and high predictability. These reports assert that the guides facilitate both chemomechanical debridement and tooth structure preservation thus ensuring the good prognosis of root canal treatment.
The purpose of this case series is to describe the use of the novel static-guided (SG) approach for the management of teeth with the canal calcification and 12 months' follow-up. The treatment protocols require special attention as it has successfully yielded the outcome with the minimal destruction of the tooth structure.
| Case Reports|| |
Case report 1
A 21-year-old Indian female patient reported with complaint of localized moderate continuous pain over the lower right side tooth region for 2 weeks. Her medical history was noncontributory. There was no congenital tooth deficiency or a familial presentation. Past dental history revealed a history of orthodontic treatment. The extraoral clinical examination revealed no significant findings. Upon, intraoral examination, mandibular right first premolar tooth (#44) revealed an intact crown [Figure 1]a with tenderness to percussion and no response to the thermal test (Pulper G; C Corporation, Tokyo, Japan). No other dental hard and soft-tissue abnormalities were noticed in the intraoral examination. The radiographic examination revealed PCO and periapical radiolucency in tooth #44 [Figure 1]b and [Table 1].
|Figure 1: (a) Illustration showing clinical view and the isolation of teeth. (b) Preoperative radiograph showing canal calcification. (c) Placement of the surgical guide. (d) Clinical view of guided access to the root canal. (e and f) Radiograph showing the working length and master cone verification. (g and h) Immediate postoperative radiograph and postoperative clinical image of the tooth. (i) Radiograph after 1-year follow-up|
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A diagnosis of pulp necrosis and symptomatic apical periodontitis with tooth #44 was established and the root canal treatment was advised using SG approach as access to the obliterated root canal could be challenging task and may induce iatrogenic errors. After explaining the treatment details to the patient, informed valid consent was obtained from the patient.
CBCT scan (Carestream 9300; Carestream Health, Rochester, NY, USA) was performed, with a slice thickness of 0.65 mm, and an exposure parameter of 84 kV, 6.0 mA, and 12 s. The CBCT images revealed root canal calcification in tooth #44 [Figure 2]a, [Figure 2]b, [Figure 2]c, [Figure 2]d, [Figure 2]e.
|Figure 2: (a-e) Illustration showing preoperative sagittal and axial sections of cone-beam computed tomography scan with the canal calcification and apical changes. (f-h) showing access to the calcified canal and path of the bur|
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Following this, a study model of mandibular arch was made by taking elastomeric impression of the arch. An AutoScan DS200 Dental 3D Scanner (Shining 3S Tech Co. Ltd., Hangzhou, China) was used to obtain the stereolithography file of the mandibular arch. This file in conjunction with the 3D implant planning software (Exocad Asia Ltd., Tsim Sha Tsui Kowloon, Hong Kong) assists in designing the template. The template to guide the bur was fabricated using a 3D Printer and Dental SG resin (Formlabs Inc., Somerville, MA, USA). The created guiding cylinder has length and diameter of 4 mm and 1.3 mm, respectively. The drilling depth for the access to the calcified part was established using CBCT data, ensuring a straight-line access [Figure 2]f, [Figure 2]g, [Figure 2]h.
The guide was checked for its fit clinically by placing it over the desired tooth (#44) region and access was gained, using MI 45F diamond bur (Mani Inc., Tokyo, Japan) with bur head diameter of 1 mm and length of 19.2 mm [Figure 1]c and [Figure 1]d. The tooth was then isolated using rubber dam. The canal patency was established using #6 k file (Dentsply Maillefer, Ballaigues, Switzerland). The working length was determined using Minipex apex locator (Dentsply Maillefer, Ballaigues, Switzerland) and verified radiographically [Figure 1]e. The glide path was established with GPS (#15/03%) rotary glide path file (Neoniti; Neolix, Châtres-la-Forêt, France). The root canal was shaped up to #25/6% using Neoniti file rotary file system (Neolix, Châtres-la-Forêt, France). The root canal was irrigated using 3% sodium hypochlorite (Novo Dental Product Pvt Ltd., Mumbai, MH, India) and saline, then dried with absorbent paper points (Kerr Corp., Romulus, MI, USA).
The tooth was obturated with gutta-percha (Dentsply Maillefer, Ballaigues, Switzerland) and EndoSeal MTA sealer (Maruchi; Wonju, Korea) using the warm vertical compaction technique. Afterward, the cavity was restored using Filtek-Z250 resin composite (3M ESPE Dental Products) [Figure 1]f, [Figure 1]g, [Figure 1]h. The 1-year follow-up examination was suggestive of absence of clinical signs and symptoms and radiographically healed periapex tissue [Figure 1]i. The patient was satisfied with the treatment. The timeline of events is summarized in [Table 2].
Case report 2
A 19-year-old Indian male patient reported with the complaint of localized intermittent pain over the upper front tooth region. The medical history was noncontributory and there was no congenital tooth deficiency or familial presentation. The patient gives a history of traumatic dental injury in the childhood. The patient has not undergone any dental treatment previously. There were no significant findings noted during the extraoral examination. Upon intraoral examination, Elli's class IV fracture was noticed in maxillary left central incisor (#21). Maxillary right central and lateral incisor (#11, #12) and maxillary left central and lateral incisor (#21, #22) were tender on percussion and did not respond to the pulp sensibility tests. No other dental hard and soft-tissue abnormalities were noticed. Radiographic examination revealed periapical radiolucency and PCO in tooth #11, #12 and #22, and there was an open root apex in upper left central incisor tooth (#21) [Figure 3]a. Based on clinical and radiographic examination, diagnosis of pulp necrosis; symptomatic apical periodontitis was established for tooth #11, #12, #21 and #22. The guided endodontic management was advised for tooth #12, #11and #22. Tooth #21 was planned to be managed with MTA apical and backfilling. Informed valid consent was obtained from the patient.
|Figure 3: (a) Illustration showing preoperative radiograph with the canal calcifications in relation to tooth #11, #12, and #22. (b and c) The isolation of teeth and placement of the surgical guide for the access to teeth #11, #12, and #22, respectively. (d-h) Radiograph showing the working length and master cone verification of tooth #11, #12, and #22|
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CBCT scan was performed, using the parameters as described in case report 1. The CBCT images revealed root canal calcifications and periapical radiolucency [Figure 4]a, [Figure 4]b, [Figure 4]c, [Figure 4]d, [Figure 4]e, [Figure 4]f. The guides were fabricated using the approach described in case report 1 and checked for fit [Figure 3]b, [Figure 3]c and [Figure 4]g, [Figure 4]h, [Figure 4]i. The endodontic treatment of tooth #12, #11, and #22 was completed using the same protocol as described in the case report 1 [Figure 3]d, [Figure 3]e, [Figure 3]f, [Figure 3]g, [Figure 3]-h and [Figure 5]a, [Figure 5]b, [Figure 5]c. For tooth #21, apical MTA plug (Angelus, Londrina, Brazil) was placed, followed by the backfilling of the remaining root canal space using EndoSeal MTA sealer (Maruchi; Wonju, Korea) and injectable thermoplasticized gutta-percha (Obtura, Spartan Endodontics, Fenton, USA) [Figure 5]a. The access cavity was restored with resin composite. The 1-year follow-up examination revealed the absence of clinical sign and symptoms of pain and periapical healing [Figure 5]d and [Figure 5]e. The patient was satisfied with the treatment. The timeline of events is summarized in [Table 2].
|Figure 4: (a-c) Illustration showing preoperative cone-beam computed tomography sagittal section with canal calcification in relation to #11, #12, and #22, respectively. (d-f) Axial section showing canal calcification. (g-i) Illustrations showing access to the calcified canal and path of the bur of the teeth #11, #12, and #22, respectively|
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|Figure 5: (a-c) Radiographs showing immediate postoperative radiograph. (d and e) Radiograph after 1-year follow-up|
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Case report 3
A 17-year-old Indian male patient reported with the complaint of broken upper front tooth and pain for 3 days. The medical and familial history was noncontributory. The patient gives a history of traumatic dental injury in the childhood. The patient has not undergone any dental treatment previously. Upon extraoral examination, no significant findings were noted. Upon, intraoral examination, discolored tooth and Ellis class IV fracture was noticed in upper right central incisor (#11) [Figure 6]a. Maxillary right central (#11) and lateral incisor (#12) and maxillary left central incisor (#21) did not respond to the pulp sensibility tests and tenderness to percussion was noticed with tooth #11, #12, and #21. No other dental hard and soft-tissue abnormalities were noticed during the intraoral examination. Radiographic examination revealed periapical radiolucency and PCO of tooth #12 and # 21 and periapical radiolucency in tooth #11 [Figure 6]b. Based on clinical and radiographic examination, the diagnosis of pulp necrosis; symptomatic apical periodontitis was made for tooth #11, #12, and #21. The guided endodontic management was advised for tooth #12 and #21. Tooth #11 was advised to be managed with conventional root canal treatment. Informed valid consent was obtained from the patient. CBCT scan was taken and revealed root canal calcifications (Tooth #12 and #21) and periapical changes (Tooth #12, #11 and #21) [Figure 7]a, [Figure 7]b, [Figure 7]c, [Figure 7]d, [Figure 7]e.
|Figure 6: (a and b) Illustration showing preoperative clinical and radiographic view©. The isolation of teeth and placement of the surgical guide for the access to teeth #12 and #21. (d-g) Radiograph showing the working length and master cone verification of tooth #12 and #21. (h and i) Immediate postoperative radiograph|
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|Figure 7: (a and b) Illustration showing preoperative cone-beam computed tomography sagittal section with canal calcification in relation to #12, and #21 respectively. (c-e) Axial section showing canal calcification and apical changes. (f and g) showing access to the calcified canal and path of the bur of the teeth #12 and #21 respectively|
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The guide was checked for its fit and the endodontic treatment of tooth #12 and #21 were completed using the same protocol as described in the case report 1 and conventional root canal treatment was performed for tooth #11 [Figure 6]c, [Figure 6]d, [Figure 6]e, [Figure 6]f, [Figure 6]g, [Figure 6]h, [Figure 6]i and [Figure 7]f, [Figure 7]g. During the endodontic shaping, file separation was encountered in tooth #12 and was retrieved with the irrigant flush [Figure 6]d. The 1-year follow-up examination was suggestive of absence of clinical symptoms and periapical healing. The patient was satisfied with the treatment. The timeline of events is summarized in [Table 2].
| Discussion|| |
The endodontic case complexity assessment criteria of American Association of Endodontists classify endodontic therapy in teeth with PCO as high difficulty. PCO cases requiring surgical interventions generally result in emotional distress for the patient, increased operative time, bone loss, and postoperative pain and complications. In such instances, the operating time to localize the canals can range from 15 min to 1 h. Calcified canals increase the risk of excessive tooth structure loss, perforation, and instrument separation even when performed by a specialist., Thus, accurate and predictable preoperative planning is strongly advised and 3D imaging can be a beneficial tool.
The advancement of planning software and 3D printing technologies has led to the development of guided endodontics. According to Krastl et al., guided endodontics is a precise approach for managing PCO cases to preserve more dental tissue, which could lead to an increase in the longevity of the treated tooth.
This case series describes the treatment of teeth with PCO and periapical bone loss with the SG endodontics technique. The SG approach requires meticulous approach especially during the access opening phase. Recently, microguided endodontic technique has been advocated, which employs the smaller head size (0.85 mm diameter) bur in order to avoid more heat generation and dentinal crack formation. In this case, the bur of head size 1 mm diameter was used. However, repeated irrigation was done while gaining access to the root canal, to reduce the rise in the temperature of the tooth structure and debris mass clogging the access cavity. After drilling to the level of cemento-enamel junction, a small flexible K file was inserted through the guide along with lubricant to allow its smooth passage. When negotiating and penetrating calcified canals, however, smaller size files are more likely to fracture. This error could reduce the success of endodontic therapy. In this case, a file of size 15k was fractured during the initial steps of biomechanical preparation. Immediate radiograph was taken to locate the fracture segment with in the canal and retrieval was attempted. A size 10 k file was inserted to bypass the fractured segment. Once the instrument bypassed a size 20 k file was inserted to loosen the fractured segment, which was then flushed out. This was followed by thorough irrigation and instrumentation with the rotary files.
Cases with PCO and apical periodontitis may require CBCT and SG-approach to retain the tooth. Endodontic success rate reported to be 89% in cases with calcified canals, while for teeth with PCO and apical periodontitis was only 62.5%. In such conditions, SG approach offers conservative management even without dental microscope. The SG endodontic approach allows for the management of such cases in short chairside time along with the conservation of the tooth structure.
The time needed to plan, design, and fabricate the guide would be relatively long when compared to conventional root canal treatment. Planning for SG approach seems to be very time-consuming and costly; however, the chair side treatment time is less and chances of tooth retention is more.,,
One limitation of this approach is employed only in straight root canals and in cases of sufficient interocclusal space. Due to the sufficient space in anterior teeth, guides with sleeves were used in all three describes cases. The application of sleeved guides does not find their role in case of molars. In contrast to this, sleeveless guides have been reported in cases with limited interocclusal space., Therefore, the success of technique should not be generalized to the molar teeth.
The another drawback of this technique could be rise in the temperature of the periodontium. However, there is no clear data in the literature regarding the degree of rising temperature. To date SG approach has been utilized for access to root canals, its utilization for simplifying the other endodontic procedures need to be studied. This case series was prepared according to the PRICE 2020 Guidelines [Figure 8].
| Conclusions|| |
The “Static Guided Endodontic” technique is safe, accurate, and conservative approach for the endodontic management of teeth with PCOs.
However, the usage should not be generalized to the molar teeth and teeth with insufficient interocclusal space and efforts must be made to refine the procedure and expand its use to the treatment of posterior teeth as well as removal of fiber posts. Nevertheless, more studies are needed to compare the performance of various planning software, materials, and designs for both 3D guides and burs.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8]
[Table 1], [Table 2]