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ORIGINAL ARTICLE
Year : 2021  |  Volume : 24  |  Issue : 11  |  Page : 1656-1661

Prevalence of apical periodontitis between root canal-treated and non-treated teeth and between genders: A cross-sectional CBCT study


1 Department of Restorative Dental Science, College of Dentistry, Jazan University, Jazan, Saudi Arabia
2 Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia

Date of Submission13-Oct-2020
Date of Acceptance27-Apr-2021
Date of Web Publication15-Nov-2021

Correspondence Address:
Dr. M Mashyakhy
Department of Restorative Dental Sciences, College of Dentistry, Jazan University, Jazan
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/njcp.njcp_627_20

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   Abstract 


Background: Apical periodontitis (AP) is one of the most important prognostic factors in almost all endodontic outcome studies. The high prevalence of AP has been reported in different populations. Aims: The aim of the present study was to investigate (a) the overall prevalence of AP among all permanent teeth, (b) the differences between root canal-treated (RCT) and non-treated teeth in association with AP, and (c) the influence of gender on AP in a Saudi Arabian population using cone-beam computed tomography (CBCT). Materials and Methods: A total of 208 CBCT radiographs (including 5,504 permanent teeth) were investigated. The CBCT machine used in this study was a 3D Accuitomo 170 (Morita, Japan) with the following features: 90 kV, 5–8 mA, 17.5 s exposure time, and 0.25 mm voxel size. The radiographs of the axial, coronal, and sagittal segments of each tooth were acquired to evaluate the presence or absence of RCT teeth and AP. The data were presented as frequencies and percentages. Z test was used to analyze the differences in proportions at the significance level of P < 0.05. Results: The overall prevalence of AP was 4.5% (264 out of 5,504 permanent teeth). AP had the highest frequencies in the mandibular and maxillary first molars (18.4 and 9.3%, respectively) with a higher prevalence in the maxillary teeth. AP was associated with endodontically treated teeth more than the untreated ones (66.3% compared with 33.7%) with a highly significant difference (P < 0.001). AP was more prevalent in females than in males but with no statistically significant difference (P > 0.05). Conclusion: AP had a low prevalence (4.5%) in all permanent teeth and was highly associated with RCT teeth (66.3%). First molars had the highest prevalence of AP. Care must be taken when examining patient radiographs to avoid missing AP, particularly in RCT teeth.

Keywords: Apical periodontitis, CBCT, cross-sectional study, root canal-treated teeth, Saudi population


How to cite this article:
Mashyakhy M, Alkahtany M. Prevalence of apical periodontitis between root canal-treated and non-treated teeth and between genders: A cross-sectional CBCT study. Niger J Clin Pract 2021;24:1656-61

How to cite this URL:
Mashyakhy M, Alkahtany M. Prevalence of apical periodontitis between root canal-treated and non-treated teeth and between genders: A cross-sectional CBCT study. Niger J Clin Pract [serial online] 2021 [cited 2021 Nov 28];24:1656-61. Available from: https://www.njcponline.com/text.asp?2021/24/11/1656/330474




   Introduction Top


Apical periodontitis (AP) is a pathological term that describes the local inflammatory response of apical tissues related to the tooth apex because of a microbial infection within the root canal system (RCS).[1],[2] One of the most important prognostic factors in almost all outcome studies is the presence of AP prior to root canal treatment or retreatment.[3–5] The prevalence of AP has been reported in many cross-sectional studies in different populations with an alarming number ranging from 6.2 to 58% with a substantially different frequency among root canal-treated (RCT) teeth.[6–10] Microorganisms within the RCS are the main cause of AP,[11],[12] and post-treatment endodontic disease leading to apical lesions can be revealed by radiographic examination.[13] AP is present quite often in RCT teeth,[14–16] although infection in the RCS that can cause AP may occur in treated and non-treated teeth.[17]

AP is usually asymptomatic and routinely found as apical radiolucencies during radiographic examination in regular dental visits.[18] Panoramic and periapical radiographs, with their inherent limitations, are widely used in regular dental examinations to assess and evaluate AP.[19],[20] However, this 2-D technology can distort some important anatomical structures and superimpose and mask important details.[18],[21] In addition, this technology is not consistent in detecting lesions that are limited to the cancellous bone and cannot reach the cortical plates.[19] Cone-beam computed tomography (CBCT) is currently utilized to overcome these limitations. CBCT is a 3-D imaging modality that allows the visualization of dental anatomy in all planes (coronal, sagittal, and axial), which improves its overall diagnostic ability in vivo.[20],[22],[23] In addition, CBCT has shown excellent accuracy value in detecting AP; CBCT found lesions that conventional radiography failed to detect.[24–30]

A literature search revealed that only one study using panoramic radiography evaluated the prevalence of AP in a Saudi Arabian population, but no study has used CBCT. Also, a few CBCT studies on AP in different populations were found.[7],[17],[31],[32] Therefore, the aim of the present study was to evaluate the overall prevalence of AP in all permanent teeth among a Saudi Arabian population using CBCT and comparing them to the other studies utilizing the same methodology. Differences between RCT and non-treated teeth in association with AP and the influence of gender on AP were also investigated as secondary objectives.


   Materials and Methods Top


The sample size for the current cross-sectional study was based on the findings of a previous investigation.[17] The earlier study indicated that around 5.9% of a study sample of 656 had AP. Therefore, with an alpha set at 5% and an addition of 10% for a possibility of dropouts, the sample size using the OPENEPI software was estimated at 105. This radiographic cross-sectional study included the CBCT scans of 208 subjects (100 males and 108 females) with 5,504 permanent teeth. The scans were collected for the patients who attended the College of Dentistry of Jazan University in Saudi Arabia between 2018 and 2020 with a mean age of 28.74 ± 9.56 years. The CBCT scans were obtained for different diagnostic reasons other than endodontics. The institute's ethical approval was attained before commencing the study (CODJU-19682). All permanent teeth were included in the investigation. Fractured teeth, distorted/unclear images, remaining roots, impacted teeth, and deciduous or permanent teeth with immature apices were excluded. The CBCT machine used in this study was a 3D Accuitomo 170 (Morita, Japan) with the following features: 90 kV, 5–8 mA, 17.5 s exposure time, and 0.25 mm voxel size. The software imaging program, i-Dixel 3D (Morita, Japan), was used to process the CBCT radiographs. The scans of axial, coronal, and sagittal segments were acquired to investigate whether the teeth are RCT or not and to evaluate the presence of apical radiolucency in a given tooth. Periapical periodontitis was considered when the low-density area associated with the radiographic apex was at least twice the width of the periodontal ligament space and/or when the disruption of the lamina dura was detected.[26],[33] Twenty CBCT images were evaluated twice with an interval of 2 weeks for reliability. Cohen's kappa test was used, and the results revealed a kappa value of 0.94 with a high significance level (P < 0.001).

Statistical analysis

The collected data were uploaded in a statistical software program for Windows (SPSS V25; IBM, Chicago, IL). The results were presented as frequencies and percentages. Z test was used to determine the significance of difference in proportions at P < 0.05.


   Results Top


A total of 5,504 permanent teeth were investigated in this study, of which 246 (4.5%) teeth had AP. In addition, 246 teeth (4.5%) had root canal treatment. Mandibular and maxillary first molars presented the highest frequency of AP (18.4 and 9.3%, respectively). The presence of AP in the maxillary teeth was higher than in the mandibular teeth. As expected, AP was associated with endodontically treated teeth more than untreated teeth (66.3% compared with 33.7%) with a highly significant difference (P < 0.001). The same was observed in the maxillary and mandibular teeth. The prevalence of AP was higher in the females than in males but without significant difference (P > 0.05; [Table 1]).
Table 1: Overall prevalence of apical periodontitis among teeth according to RCT and gender

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[Table 2] shows the prevalence of AP among the maxillary teeth. Its prevalence was higher in the maxillary first molars (9.3%) and maxillary centrals (7.8%). All maxillary endodontically treated canine teeth, 94.7% of maxillary second premolars, and 75.0% of maxillary first premolars were significantly associated with AP (all P < 0.001). In general, the prevalence of AP was higher among RCT teeth than untreated teeth with significant difference (P < 0.05; [Table 2]). Mandibular endodontically treated canines and first premolars (100%), mandibular second molars (66.7%), and mandibular first molars (62.9%) were significantly (P < 0.05) associated with AP. It was more associated with untreated mandibular central and lateral incisors unlike maxillary teeth in which AP was more associated with treated teeth. More details are shown in [Table 3].
Table 2: Prevalence of apical periodontitis among all and RCT maxillary teeth

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Table 3: Prevalence of periapical radiolucency among all and RCT mandibular teeth

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Differences between males and females to the prevalence of AP are presented in [Table 4]. No significant differences were observed in the prevalence of AP between both genders except for maxillary first premolars in which 93.8% of the teeth (n = 15) with AP were found in females and only 6.2% (n = 1) in males.
Table 4: Prevalence of apical periodontitis according to gender among all maxillary and mandibular teeth

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   Discussion Top


This is the first study in a Saudi population utilizing CBCT and it was used in this retrospective cross-sectional study because it is more accurate in detecting AP compared to conventional radiography.[13],[34],[35] A study[13] showed a substantial difference among CBCT, periapical, and panoramic radiograph in detecting apical radiolucency in the same teeth (63.3, 35.3, and 17.6%, respectively). The same author found that conventional radiography might underestimate AP prevalence because approximately 30–50% mineralized bone loss is needed for the radiographic detection of a lesion. By contrast, CBCT overestimates the presence of AP and shows a false-positive result in RCT teeth.[36] Small field of view (FOV) is recommended in endodontics[20] to precisely detect apical pathoses. However, we included full head scans in this prevalence study to provide a true convenient sample where the scans were taken for different diagnostic reasons other than endodontics. Small FOV for endodontics were excluded to remove the bias of including scans that already included AP.

We evaluated the prevalence of AP in 5,504 teeth and found that the overall frequency of AP was 4.5%, which is very similar to the other recent studies that utilized CBCT in different populations (3.4, 5.8 and 5.9% in Brazilian, Scottish, and Belgian population, respectively) and lower than a report from Portuguese population 10.4%.

A previous study by Estrela et al.[13] concluded that CBCT imaging modality had a higher sensibility for AP detection and conventional radiographs tend to underestimate the presence of apical radiolucency. However, a recent panoramic radiographic study[6] in a Saudi population from different cities evaluated 926 patients (25,028 teeth) and reported a slightly higher frequency of AP 6.2% compared to our results. In addition, our findings fell within the lower range (1.4–15.1%) of previous studies that used panoramic radiographs[15],[37],[38]

The accuracy of CBCT might be related to the nature of the sample and study design, where patients referred for endodontic treatment or teeth with previous RCT may normally present with AP, and once you compared the frequency of AP in these samples, CBCT will show more prevalence because of its accuracy.[13] While this is not the case once the sample was collected from different patients who were exposed to radiography for different diagnostic and treatment purposes. It seems that there is no difference in the frequency of AP detected by panoramic radiography and CBCT, with the panoramic imaging modality having the advantage of being more accessible, cheaper, and giving a complete overview of all the teeth at once.

AP was more frequent in maxillary teeth (5.1%) compared with mandibular teeth (3.8%). Mandibular and maxillary first molars presented the highest frequency of AP (18.4 and 9.3%, respectively). This finding is in agreement with the previous studies.[7],[31] The higher frequency of AP in first molars might be explained by the early eruption of first molars and their complex occlusal and internal root anatomy, which make them more prone to caries and result in difficulties in appreciating their RCT during chemo-mechanical shaping and cleaning.[35],[39],[40]

One interesting finding as a secondary finding of this study was that the prevalence of RCT teeth (4.5%, 246 out of 5,504 teeth) among the samples was the same as AP (4.5%). However, the presence of AP was significantly associated with endodontically treated teeth compared with non-treated teeth (66.3 and 33.7%, respectively; P < 0.001). This finding is consistent with three previous CBCT studies,[7],[41],[42] which presented a strong association between RCT teeth and AP (55.5, 55.5, and 59.5%, respectively).

This finding is best explained by the presence of microorganisms within the RCS of RCT teeth as a consequence of the inability of clinicians to perform adequate endodontic treatment.[43],[44] In addition, outcome studies have reported many factors associated with failed RCT, including poor root canal filling, missed canals, remaining intercanal infection, improper coronal seal, and iatrogenic errors, which lead to the presence or persistence of AP.[45–49]

The influence of gender on AP was also investigated in the present study, and the results showed no association between gender and the presence of AP. We found that females tend to have a higher frequency of AP compared with males with no statistically significant difference (P > 0.05) except for maxillary first premolars, in which 15 teeth with AP were found in females and only one tooth with AP was found in males. Another study in the same population[6] used panoramic radiography and reported no differences in gender in association with AP. Other studies utilized CBCT in Belgium,[17] Brazilian,[31] Scottish[32] populations and found no substantial difference in the prevalence of AP between males and females. Our findings and other previously mentioned studies showed that gender appears to have no influence on the presence or absence of apical pathology.

The main limitation of the present study is its nature as a cross-sectional evaluation of a given situation at a certain point in time in the investigated population.[50] This type of study lacks important information, including the preoperative diagnosis of a tooth, time since the treatment was done, the quality of the treatment, and the skills of the practitioner, which affect the outcome; therefore, a cause-effect relationship cannot be established. However, these types of studies notify about illnesses that represent the real clinical situations which need to be addressed and managed properly by establishing preventive measures.

Based on our findings and in comparison with the previous studies that utilized both conventional or CBCT imaging modalities, we could recommend not to expose a patient for CBCT for the sake of finding apical pathosis. Instead, panoramic radiograph should be the first line in examining the patient for a comprehensive diagnosis then periapical radiography and/or small FOV CBCT if more details are needed.

New retrospective studies comparing the prevalence of AP using panoramic radiography and CBCT of the same patients are recommended to detect the accuracy of detection of apical pathoses.


   Conclusion Top


The overall prevalence of AP and RCT teeth was 4.5%, and AP was highly prevalent in the first molars. The frequency of AP was highly associated with RCT teeth 66.3%. Gender had no significant influence in the presence of AP. CBCT and conventional radiography of a patient should be carefully evaluated for the presence of AP, especially in RCT teeth.

Authors' contribution

MM and MA participated in the design of the study, data collection, interpretation of the data and drafted the manuscript. All authors read and approved the final manuscript.

Acknowledgments

We would like to thank Dr. Rawan Alfaifi, Dr. Fatimah Hadi, and Dr. Hashimah Alhazmi for their help in collecting and organizing the data.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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