Comparative Evaluation of Clinical and Radiographic Success of Pulpectomy Done with and without Dental Operating Microscope in Pediatric Patients: An In Vivo Study
Corresponding Author: Ferah Rehman, Department of Pediatric and Preventive Dentistry, Maulana Azad Institute of Dental Sciences, Delhi, India, Phone: +91 8826246696, e-mail: firstname.lastname@example.org
Aim: To assess the clinical and radiographic success of conventional pulpectomy and pulpectomy done under an endodontic microscope over a period of 12 months.
Materials and methods: The study was conducted as a single-blinded, parallel-group prospective, randomized, and controlled clinical trial. The enrollment of the study involved the assessment of 258 deciduous molars for eligibility as per the inclusion criteria. A total of 104 teeth were allocated to each group, that is, group I (conventional pulpectomy) and group II (pulpectomy under microscope). However, due to unavoidable circumstances during the coronavirus disease 2019 (COVID-19) pandemic, 98 and 90 teeth were treated in each group, respectively. Pulpectomy in both groups was done using standard protocol except for the use of an endodontic microscope in group II. The clinical and radiographic outcomes were assessed by an independent blinded observer and analyzed using appropriate statistical tests.
Results: The clinical success at 6 months is 95.7 and 96.5%, and at 12 months is 96.6 and 97.7% in groups I and II, respectively. The radiographic success at 6 months is 93.5 and 95.4%, and at 12 months is 95.5 and 98.8% in groups I and II, respectively. The overall success rates of both groups with statistically no significant differences.
Conclusion: The present study concludes comparable results are achieved using an endodontic microscope to conventional pulpectomy without magnification.
How to cite this article: Kumar G, Rehman F. Comparative Evaluation of Clinical and Radiographic Success of Pulpectomy Done with and without Dental Operating Microscope in Pediatric Patients: An In Vivo Study. Int J Clin Pediatr Dent 2023;16(S-2):S155–S160.
Source of support: Nil
Conflict of interest: None
Keywords: Clinical and radiographic success, Endodontic therapy, Manual technique, Primary dentition, Primary teeth, Pulpectomy, Rotary technique
Pediatriс endodontics plays a crucial role within the field of pediatric dentistry. A pulpectomy is a common treatment for the prevalent issue of carious teeth in primary dentition, where root canals become infected, and the infection spreads around the apical foramen and furcation area. The objective of performing a pulpectomy in primary teeth is to thoroughly eliminate bacterial infection through effective endodontic instrumentation and proper irrigation. Additionally, the root canals are filled with a suitable material to ensure successful obturation. The success of this procedure is determined not only by the resolution of clinical and radiological signs and symptoms but also by the natural exfoliation of the treated primary tooth and the unobstructed eruption of the succeeding tooth.1
When the necrotic material in the canal cannot be effectively cleaned, sterilized, and adequately filled, the chances of a successful pulpectomy decrease. The variation in root canal anatomy is a significant contributing factor to the failure of root canal treatment in primary molars.
The intricate nature of root canal systems establishes the parameters that influence the likelihood of success in root canal therapy, particularly when addressing primary mandibular first molars.2 Over the past 15 years, there has been a remarkable advancement in the field of endodontics, characterized by a surge in new technologies, instruments, and materials for both nonsurgical and surgical procedures. These innovations have significantly enhanced the precision of endodontic treatments. Among these advancements, the introduction and widespread utilization of the operating microscope (OM) has revolutionized the practice of endodontics, marking a significant milestone. Apotheker and Jako introduced the dental OM (DOM) in 1981.3 Prior to the introduction of the OM, the detection of issues such as ledges, perforations, blockages, or broken instruments in endodontic procedures relied solely on subjective perception. Clinical management of these problems was inherently unpredictable.
Endodontic procedures were predominantly conducted without visual aid, requiring the endodontist to rely heavily on their tactile dexterity, mental visualization, and determination. However, with the advent of the DOM, even the most challenging obstacles within the straight section of the root canal system, including those situated at the apical region, can now be readily observed and effectively addressed. It is worth noting that there is limited availability of literature concerning the utilization of the DOM, specifically in pediatric cases. A study conducted by Rehman et al.4 evaluated the knowledge, attitude, and practice of pediatric dentists regarding the use of a DOM in children. The findings revealed that a majority of the pediatric dentists surveyed were familiar with the utilization of DOM in their field. However, only a few possessed knowledge about the specific magnification levels offered by DOM. While the majority agreed that DOM was beneficial in locating canals in deciduous teeth, opinions varied when it came to the behavior management aspect of treating children using DOM, resulting in a controversial viewpoint. Sayed et al.5 conducted a study to explore the impact of utilizing the live visual output of the DOM as an adjunct to the tell-show-do technique in pediatric patients. The aim was to enhance the child’s engagement in the procedure and reduce fear of the unknown. The findings demonstrated a notable decrease in anxiety levels and improved patient compliance during visits where DOM was employed. This suggests that DOM can be effectively utilized in pediatric patients, similar to its advantages in adult care. Building upon this background, the current project was designed with the objective of evaluating the influence of the endodontic microscope on the outcomes of root canal treatment in deciduous molars.
MATERIALS AND METHODS
The outline of this in vivo study was assessed and approved by the Institute Ethical Committee. The patients were recruited from the Outpatient Department of Paediatric and Preventive Dentistry, Maulana Azad Institute of Dental Sciences, New Delhi, India. The patients in the age group of 3–8 years, irrespective of gender having primary molars with deep carious lesions and necrosed pulps, were screened for inclusion in the study. The study was conducted as a single-blinded, parallel-group prospective, randomized, controlled clinical trial.
The enrollment of the study involved the assessment of 258 deciduous molars for eligibility as per the inclusion criteria. Out of 258 molars, 50 teeth were excluded (38 teeth did not meet the inclusion criteria, and 12 patients/parents refused to participate). A total of 208 deciduous molars were finally selected that fulfilled the inclusion criteria. A total of 208 deciduous molars were randomly divided into two groups. Each group consisted of 104 deciduous teeth.
Group I (control group): Comprised of 104 teeth treated with conventional pulpectomy.
Group II (experimental group: Comprised of 104 teeth treated with pulpectomy under an endodontic microscope.
Simple random sampling was done using computer-generated numbers.
A detailed history of the participants was obtained, followed by a thorough clinical and radiographic examination. Intraoral preoperative radiographs were taken for screening of the periapical and furcation areas. Paralleling cone technique was performed for standardizing the periapical radiographs using radiovisiography sensor size 0 (Durr Dental, Bietigheim-Bissingen, Germany) with the help of a film positioner.
The armamentarium used in both groups is shown in Figure 1. After administering local anesthesia using 2% lignocaine with 1:100,000 epinephrine, the tooth was isolated with a rubber dam. A cavity outline form was established, and caries was removed. After caries removal, coronal access was performed using no. 33 high-speed bur with water spray to unroof the pulp chamber. After chamber access with a fissure bur in a high-speed handpiece, necrotic pulp tissue was removed using a sterile sharp spoon excavator and irrigated with 1% sodium hypochlorite (NaOCl). Canal orifices were located with an endodontic explorer, and the root length was determined using an electronic apex locator (EAL). A rubber stop was placed at the determined working length on the number 15 K-file, which was used to negotiate all the canals before instrumentation with rotary files. Pedo files from Neo Endo Flex, which is a two-file system, were used for cleaning and shaping canals.
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To ensure thorough debris removal, copious irrigation with 1% NaOCl was performed after each instrument was used. The canals were then dried using sterile paper points, and Metapex was directly filled using a prepacked syringe. The clinical and radiographic details of group I are illustrated in Figure 2.
In cases where the canals exhibited excessive bleeding or pus exudates, they were carefully dried with paper points. A creamy consistency paste was prepared by mixing calcium hydroxide with distilled water, which was then applied to the root canals using a lentulo spiral. During a subsequent appointment (7–14 days after medication), if no signs or symptoms of inflammation were observed, the canals were irrigated with 1% NaOCl, dried, and prepared for obturation. However, if inflammation was present, the canals were recleaned and remedicated, and the root canal filling procedure was postponed.
Following the root canal filling with metapex, a thick mixture of zinc oxide eugenol (cavit) was placed in the coronal pulp chamber. In a subsequent visit (after 1 day), the patient was recalled, and the temporary restoration was removed. The final restoration was then performed using glass ionomer cement.
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All treated deciduous molars were restored with preformed primary stainless steel crowns (3M ESPE, Germany) using glass ionomer luting cement after tooth preparation. The children were recalled for clinical and radiographic examination postoperatively at 3, 6, and 12 months. The expected follow-up at 3 months could not be done due to the coronavirus disease 2019 (COVID-19) pandemic and lockdown restrictions. The teeth were examined clinically and radiographically at follow-up visits by an independent observer (GK) who was blinded to the procedure.
The clinical procedure in group II is the same as group I, which is described above, with the additional use of a DOM while doing the procedure. The procedure done under both groups is shown in Figure 3. The clinical and radiographic presentation of the case done under a microscope (group II) is shown in Figure 4.
Data collected was in the form of a number of teeth showing clinical and radiographic signs at follow-up visits. The data were entered into MS Excel spreadsheets and analyzed using Statistical Package for the Social Sciences software. Data were presented as frequency and percentage. Intergroup comparison was made by Chi-squared test with a p-value of <0.5 considered significant.
The number of participants who were initially enrolled in the study was 104 in each group, but due to the COVID-19 outbreak, only 98 children in group I and 90 children in group II were given treatment within the stipulated time period. The demographic details of the study participants are represented in Table 1 and show comparable distribution in both groups with respect to age, gender, and teeth type.
|Parameters||Group I (n = 98) (%)||Group II (n = 90) (%)||p-value|
|Age (in years)||0.832|
|Mean ± standard deviation||5.49 ± 0.997||5.52 ± 0.986|
|Male||64 (65.3)||60 (66.7)|
|Female||34 (34.7)||30 (33.3)|
|First primary molar||43 (43.9)||42 (46.7)|
|Second primary molar||55 (56.1)||48 (53.3)|
Table 2 represents the number of teeth showing different types of clinical symptoms at baseline, 6, and 12 months in both groups. At the 6-month follow-up visit, five children in group I and three children in group II could not report as their families migrated to native villages due to loss of employment during the lockdown period. Four teeth in group I showed pathologic mobility and gingival abscess, which were classified as failure cases, and extraction was done for the same. At 12 months, the teeth which were extracted were excluded from the evaluation. As is evident from the no statistically significant difference is observed in the clinical representation of both the groups.
|Clinical signs and symptoms||Baseline||6 months||12 months|
|Group I (98)||Group II (90)||p-value||Group I (93)||Group II (87)||p-value||Group I (89)||Group II (87)||p-value|
|Pain||98 (100)||90 (100)||NA||4 (4.3)||3 (3.4)||NA||0(0)||0 (0)||NA|
|TOP||45 (45.9)||33 (36.7)||0.255||8 (8.6)||3 (3.4)||0.255||3 (3.3)||2 (2.3)||0.733|
|Gingival abscess||25 (25.5)||25 (27.8)||0.852||1 (0.1)||0 (0)||0.852||0 (0)||0 (0)||NA|
|Teeth mobility||14 (14.3)||11 (12.2)||0.840||3 (3.2)||0 (0)||0.840||0 (0)||0 (0)||NA|
|Extraoral swelling||57 (58.2)||46 (51.1)||0.410||0 (0)||0 (0)||0.410||0 (0)||0 (0)||NA|
Table 3 represents the number of teeth showing different radiological findings. At 6 months, it was observed that six teeth showed increased intraradicular radiolucency, out of which four were extracted because of poor prognosis as evidenced by their clinical symptoms as well, and two teeth were further followed. At 12 months, the same two teeth showed increased intraradicular pathology, and in addition, two more teeth showed the pathologic radiolucency and hollow-out effect of metapex. In group II, less number of teeth showed radiological signs, although two teeth in group II showed external root resorption, which was considered a normal physiological condition depending upon the age of the child being 9 years and the teeth involved as first molar.
|Radiographic sign||Baseline||6 months||12 months|
|Group I (98)||Group II (90)||p-value||Group I (93)||Group II (87)||p-value||Group I (89)||Group II (87)||p-value|
|Periapical radiolucency||69 (70.4)||61 (67.8)||0.817||0 (0)||0 (0)||NA||0 (0)||0 (0)||NA|
|Intraradicular radiolucency||81 (82.7)||73 (81.1)||0.932||6 (6.8)||4 (4.6)||0.669||4 (4.6)||1 (1.2)||0.833|
|Internal resorption||2 (2.0)||0 (0.0)||0.515||0 (0)||0 (0)||NA||0 (0)||0 (0)||NA|
|External resorption||34 (34.7)||27 (30.0)||0.596||0 (0)||0 (0)||NA||2 (2.3)||0 (0)||1.00|
Table 4 depicts the overall success rates of both groups with statistically no significant differences.
|Success||Follow-up period||Group I||Group II||p-value|
|Clinical||6 months||95.7% (89/93)||96.5% (84/87)||0.922|
|12 months||96.6% (86/89)||97.7% (85/87)||0.733|
|Radiographic||6 months||93.5% (87/93)||95.4% (83/87)||0.669|
|12 months||95.5% (85/89)||98.8% (86/87)||0.833|
The primary objective of an endodontic intervention is to restore the functionality of the affected tooth by promoting healing and preserving periapical tissue integrity while eliminating microorganisms to prevent reinfection.6 Numerous studies have focused on primary tooth pulpectomies, investigating various aspects such as filling materials,7,9 irrigants,10 instrumentation methods, and their varying success rates ranging from 56 to 100%. However, these studies have limitations, including small sample sizes and relatively short follow-up periods of less than 18 months.
A recent retrospective study conducted by Dou revealed that the survival rate of primary anterior teeth at 24 months after pulpectomy was 72.1%, which was higher than that of primary molars (57.1%).11 Although studies have reported different success rates between primary anterior teeth and molars, the statistical significance of this difference is inconclusive due to small sample sizes, particularly in anterior teeth.12,13 This discrepancy is attributed to the morphological differences observed in primary teeth, where anterior teeth typically have a single canal with fewer lateral branches or root tip bifurcations, whereas primary molars often exhibit various forms of accessory root canals.14
The complex root canal structure in primary molars poses challenges in infection removal, as the presence of remaining bacteria can lead to pulpectomy failure. The lack of satisfactory survival rates for primary molars following root canal treatment motivated the present study, which aimed to evaluate the outcome of root canal treatment in primary molars using a DOM. Despite the advantages of magnification in endodontic procedures, there is a scarcity of literature on the use of magnifying devices in pediatric dentistry. It is often assumed that the use of magnification in pediatric treatment may evoke anxiety and noncooperation among children, limiting its application in this field. However, a study by Sayed et al.5 demonstrated the positive effect of live visual output from a DOM in reducing anxiety and increasing patient compliance during restorative procedures in children, showing promising results.
Considering the need for better outcomes in primary molar root canal treatment, the present study was designed as a single-blinded, randomized, and controlled trial. A blinded observer conducted the follow-up evaluations of clinical and radiographic signs. Simple random sampling was employed to select patients requiring endodontic procedures, ensuring equal chances of receiving one of the two treatment procedures. Various factors can influence the outcome of pulpectomy treatment, including tooth diagnosis, pathological conditions, nonvital pulp treatment, medications, irrigants, temporary materials, and permanent restorations.15 The present study ensured a fair distribution of teeth with mild, moderate, and severe pathological conditions, as well as a balanced distribution of gingival abscesses, tooth mobility grades, and extraoral swelling.
To minimize contamination and enhance success, all selected teeth underwent the procedure under rubber dam isolation, which provides optimal isolation from saliva bacteria.16 Additionally, 1% NaOCl was used for irrigation based on the findings of Verma et al.,10 who reported no significant difference in clinical outcomes between low (1%) and high (5%) concentrations of NaOCl. Irrigation was performed using 1% NaOCl at a gentle flow rate, with constant movement of the needle to prevent penetration into periradicular tissues.
The working length of the treated tooth was determined using an EAL, which has been demonstrated to be the most accurate method compared to radiographs and tactile methods.17 The use of EAL helps reduce operation time, which is crucial for maintaining patient cooperation, particularly in single-visit pulpectomy procedures often performed in pediatric dentistry.18
Rotary instrumentation was employed for chemo-mechanical preparation, as indicated by a systematic review and meta-analysis by Manchanda et al.,19 which reported similar clinical and radiographic success reduced postoperative pain, and shorter instrumentation time compared to manual techniques. Rotary files also improve patient cooperation by reducing treatment time and minimizing fatigue.20 The operator’s training in rotary instrumentation is essential for controlling working length since there is a decrease in tactile sensitivity during apical preparation compared to manual techniques.
The clinical and radiographic criteria employed for scoring were similar to those used in previous studies, such as the work by Nakornchai et al.9 Metapex, a calcium hydroxide-based paste, was used for obturation in both groups, demonstrating good clinical and radiographic success rates, as supported by other researchers.21-23 The overall clinical success rate at 12 months was 96.6% in the conventional group and 97.7% in the endodontic microscope group. The use of the DOM for pulpectomy procedures in primary molars showed a high clinical success rate, which aligns with previous prospective8,9,24-26 and retrospective studies27 reporting success rates of 96–100% at 12–22 months of follow-up. Regarding radiographic success, both groups exhibited an overall success rate of 95.5 and 98.8% at 12 months follow-up, surpassing some previous studies8,24,26 results. The low radiographic success rate reported in a study by Nakornchai et al.9 may be attributed to their sample selection, focusing on teeth with a poor prognosis. In the present study, most teeth included had slight intraradicular radiolucency, and previous research suggests that success differences may stem from the preoperative condition of the tooth rather than the filling technique itself.
Overall, the success of primary tooth endodontic procedures depends on factors such as preoperative pathological condition, isolation, chemo-mechanical preparation, instrumentation, debridement, root canal filling material, and restoration. In the present study, these factors were carefully controlled, and the procedure was performed by a single trained pediatric dentist, leading to successful clinical and radiographic outcomes regardless of conventional or microscopic endodontic approaches.
The impact of an endodontic microscope on the outcome of root canal treatment of deciduous molars showed promising results. Magnification improves the clinical outcome but requires a high-cost investment and training for the personnel using it. Additionally, conventional pulpectomy yields similar results provided, and standard protocols are followed. Thus, the present study concludes comparable results are achieved using an endodontic microscope to conventional pulpectomy without magnification.
We would like to acknowledge the financial support of the Department of Science and Technology, the Science and Engineering Research Board, and the Government of India for giving us the opportunity to carry out this project.
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