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Research Article
ARTICLE IN PRESS
doi:
10.25259/JGOH_22_2022

Impact of COVID-19 pandemic on using dental radiography

Department of Dentomaxillofacial Radiology, Ankara Yildirim Beyazit University, Etlik-Keçiören/Ankara, Turkey
Corresponding author: Berrin Çelik, Assistant Professor, Department of Dentomaxillofacial Radiology, Ankara Yildirim Beyazit University, Faculty of Dentistry, Etlik-Keçiören/ Ankara, Turkey. bcelik@ybu.edu.tr
Licence
This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: YildızerKeris E, Çelik B, Arslan ZB. Impact of COVID-19 pandemic on using dental radiography. J Global Oral Health, doi: 10.25259/JGOH_22_2022

Abstract

Objectives:

This study aimed to analyze the impact of the COVID-19 pandemic on using dental radiography.

Materials and Methods:

This retrospective study included adult patients who applied at 3-time intervals reflecting changes in the course of the COVID-19 pandemic in 2020 (T1-T2-T3). Patients’ demographics, the number of radiographic and clinical procedures provided, and radiographic findings were noted during T1-T2-T3.

Results:

The frequency of using dental radiography was the lowest at the beginning of the pandemic and significantly increased over time. Using radiography increased when the number of COVID-19 cases increased. The course of the COVID-19 disease did not affect using radiography by dentists. The use of dental radiography in elderly patients was found to be less than in younger patients. Invasive treatments applied to the patients who had radiographs were significantly higher than those who had not at T2 and T3.

Conclusion:

This study demonstrated the changes in dental radiographic procedures during the pandemic. It was ordered to avoid intraoral radiography as much as possible due to aerosol production during the COVID-19 pandemic. To make better use of dental radiography, manufacturers should improve extraoral radiography with better image quality with lower radiation doses.

Keywords

COVID-19
Dental radiography
Intraoral radiography
Panoramic radiography
Cone-beam computed tomography

INTRODUCTION

The COVID-19 pandemic affected the world and changed all healthcare services. The dental practice had a higher risk of cross-infection compared to many medical disciplines due to droplets and aerosols.[1] Infection control protocols were published in dentistry and oral maxillofacial radiology applications specific to COVID-19 disease.[2-4] It was ordered that intraoral radiography should not be used as much as possible due to aerosol production, and extraoral radiographs should be preferred instead of it.[1,5] While the use of radiography may be needed in the diagnosis and treatment planning of urgent cases,[2,6] the limited use of intraoral radiography makes it difficult to reveal the clinical problem. The basic principle in the imaging request is to clarify that clinical evaluation is insufficient for definitive diagnosis and treatment planning.

Articles presenting a strategy for the practice of oral and maxillofacial radiology during the COVID-19 pandemic are very limited[2-4] and clinical data on changes in radiographic procedures were not presented.

The purpose of our study was to analyze using dental radiography by evaluating and comparing the frequency of radiographs of patients admitted to a university dental hospital and the characteristics of the patients during the COVID-19 pandemic time points reflecting changes in the course of the disease in 2020.

MATERIALS AND METHODS

This study was approved by the Ethics Committee of Ankara Yıldırım Beyazıt University (2021–68). We planned a retrospective study that included adult patients who applied to Ankara Yıldırım Beyazıt University Faculty of Dentistry.

We collected data at three different time intervals. These periods were:

  • T1: The 3 days of the month when the first official COVID-19 case was announced in Turkey, several restrictions were started, and when our hospital’s adaptation process begins to improve (March 23–25, 2020).

  • T2: The 3 days of the month when the number of cases decreased in Turkey and the restrictions were eased with gradual normalization (June 1–3, 2020).

  • T3: The 3 days of the month when the number of COVID-19 cases increased again (second peak in Turkey) and tighter restrictions started (November 1–3, 2020).

The data of the study group were obtained from electronic hospital records. Patients with inadequate radiographic image quality and patients under the age of 15 were excluded from the study. Patients with a full diagnostic record were included in this study.

Patients’ age and sex and dental clinical and radiographic procedures provided (on the day of their application to the hospital at T1, T2, and T3) were noted and their panoramic, intraoral, and Cone-beam computed tomography (CBCT) radiographs were examined. Each image was evaluated blindly each other. Radiographic findings were evaluated according to eight subcategories: Caries (primary/ secondary), pulp-related caries, periapical infectious lesion, periodontal disease, pericoronitis, crown/cusp/root fracture, impacted teeth, and others (such as cyst, tumor, jaw fracture, periimplantitis, and temporomandibular disorder findings). For this study, common causes of dental urgency[7] were considered when creating these categories. The radiographic diagnosis was made by the consensus of three dentomaxillofacial radiologists (EYK, ZBA, and B.Ç).

The dental clinical procedures included invasive dental procedures (aerosol and/or non-aerosol generating) and non-invasive procedures (prescription/advise/no dental procedure). We did not categorize dental treatments as aerosol and/or non-aerosol generating because the procedures that produce aerosols were not clear.[8,9] The items of invasive treatments provided were classified into six main treatment areas: Restorative, endodontic, surgical prosthetic, periodontal treatments, and other surgical procedures. Orthodontic urgencies were not included in the study because we cannot see the records of orthodontics and pedodontics clinics in the electronic hospital software program.

Statistical analysis

Data were analyzed with Chi-square and Kruskal–Wallis H test using SPSS Version 21 (IBM Corp, Armonk, NY) statistical program. The significance level was determined as P < 0.05.

RESULTS

Patients’ demographics

The comparisons of the patients’ demographics and distribution of radiographic procedures among the COVID-19 pandemic time points (T1, T2, and T3) are presented in Table 1.

Table 1:: Patients” demographics during COVID-19 pandemic and distribution of radiographic procedures.
T1 T2 T3 P
Age
Average 47.4 43.3 43.3 0.0001
Median 48 43 42
Min-max 15–88 15–90 15–93
Gender (number/%) Total
Female 296 (44.4) 458 (49.5) 472 (52.6) 1226 (49.3) 0.006
Male 370 (55.6) 468 (50.5) 425 (47.4) 1263 (50.7)
Radiographic procedures (number/%)
Patients without a radiographic procedure 644 (96.7) 599 (64.7) 479 (53.4) 1722 (69.2) 0.0001
Patients with a radiographic procedure 22 (3.3) 327 (35.3) 418 (46.6) 767 (30.8)
Total 666 (100) 926 (100) 897 (100) 2489 (100
Radiographic technics (number/%)
Intraoral 2 (9.1) 4 (1.2) 45 (10.8) 51 (6.6) 0.0001
Panoramic 22 (100) 326 (99.7) 391 (93.5) 739 (96.3) 0.0001
CBCT 0 (0) 1 (0.3) 9 (2.2) 10 (1.3) 0.084

The total number of patients provided radiography is less than the total number of radiographs because some patients had one more radiograph. P<0.05, CBCT: Cone beam computed tomography

The mean age of the patients was significantly higher at T1 (47.4%) than at T2 (43.3%) and at T3 (43.3%) (P = 0.0001 < 0.05). The frequency of male patients was found to be higher than females at T1 and T2, while, found to be lower than for females at T3 (P = 0.006 < 0.05).

Radiographic procedures of the patients

The frequency of the patients who had a radiographic procedure was the lowest at T1 and was the highest (46.6%) at T3 [Table 1].

Radiographic procedures of those aged 65 and over

The number of radiographic procedures for patients aged 65 and over was lower than for those aged 64 and below [Table 2].

Table 2:: Correlations of radiography provided (per patient) of the age groups at T1, T2, and T3.
Age groups Radiography
Without a radiographic procedure (n/%) With a radiographic procedure (n/%) Total (n/%) P
T1
65 and over 97 (99) 1 (1) 98 (100) 0.141
64 and under 547 (96.3) 21 (3.7) 568 (100)
T2
65 and over 72 (75.8) 23 (24.2) 95 (100) 0.011
64 and under 527 (63.4) 304 (36.6) 831 (100)
T3
65 and over 81 (77.9) 23 (22.1) 104 (100) 0.0001
64 and under 398 (50.2) 395 (49.8) 793 (100)

n: Number of patients. The total number of patients provided radiography is less than the total number of radiographs because some patients had one more radiograph. P < 0.05

Radiographic findings

Values for radiographic findings at T1, T2, and T3 are provided in Table 3. Radiographic images of 16 of 767 (2%) patients were normal.

Table 3:: Radiographic findings of the patients during the pandemic.
T1 T2 T3 T1+T2+T3 P
n % n % N % n %
Caries 1 4.5 104 31.7 210 50.2 315 41.0 0.0001
Caries related pulp 10 45.5 234 70.9 270 64.6 514 66.8 0.0001
Periapical infectious lesion 10 45.5 124 37.5 101 24.2 235 30.5 0.0001
Periodontal disease 2 9.1 91 27.6 191 45.7 284 36.9 0.0001
Pericoronitis 3 13.6 25 7.6 39 9.3 67 8.7 0.513
Crown-root fracture 4 18.2 93 28.2 119 28.5 216 28.1 0.577
Impacted teeth 3 13.6 72 22.0 101 24.2 176 22.9 0.452
Other diseases 0 0.0 11 3.4 2 0.5 13 1.7 0.008

n: Number of patients. P<0.05

Variables of using CBCT are shown in Table 4. Reported signs related to the CBCT images were limited to the scanning area.

Table 4:: Characteristics of the patients who had CBCT and their radiographic features at post-COVID time intervals.
Age Gender Time interval Using conventional radiographs prior to CBCT Radiographic findings of the conventional radiographs Radiographic findings of the CBCT
27 Female T2 Panoramic Other diseases Other diseases
19 Female T3 Both panoramic and intraoral Caries, deep caries, pericoronitis, impacted teeth Impacted teeth
20 Female T3 Both panoramic and intraoral Caries, deep caries, pericoronitis, impacted teeth Impacted teeth
30 Female T3 Panoramic Impacted teeth Impacted teeth
61 Female T3 Panoramic Periodontal disease, impacted teeth Other diseases
32 Male T3 Panoramic Other diseases Other diseases
47 Male T3 Panoramic Periapical infection Periapical infection
61 Male T3 Panoramic Other diseases Other diseases
50 Male T3 Panoramic Other diseases Other diseases
30 Female T3 Panoramic Periodontal disease Periodontal disease
48 Female T3 Panoramic Other diseases Other diseases

CBCT: Cone beam computed tomography

Correlations between treatments and radiography provided

The correlations between provided treatments and radiography at T1, T2, and T3 are presented in Table 5.

There was no significant dependence between providing radiography and dental treatments regarding invasive and non-invasive procedures at T1 (P > 0.05) while invasive treatments applied to the patients who had radiographs (48% at T2 and 47.6% at T3) were significantly higher than those who did not (28.4% at T2 and 28.2% at T3) (P < 0.05).

Table 5:: Numbers and distribution of treatments and correlations of invasive and non-invasive treatments radiography provided (per patient) among T1-T2-T3.
T1 T2 T3 Total P
N % n % n % n %
Number of the patients provided treatment
Non-invasive 493 74 599 64.7 563 62.8 1655 66.5 0.0001
Invasive 173 26 327 35.3 334 37.2 834 33.5
Number of the invasive treatments
Restorative treatment 2 1.2 59 18.0 45 13.5 106 12.7 0,0001
Endodontic treatment 0 0.0 5 1.5 11 3.3 16 1.9 0.0001
Surgical procedure 11 6.4 168 51.4 206 61.7 385 46.2 0.031
Prosthetic procedure 156 90.2 99 30.3 87 26.0 342 41.0 0,031
Periodontal treatment 5 2.9 4 1.2 1 0.3 10 1.2 0.0001
Other surgical procedures 0 0.0 12 3.7 22 6.6 34 4.1 0.002
Radiography P
Dental treatment Without a radiographic procedure (n/%) With a radiographic procedure (n/%) Total (n/%)
T1 493 (74) 0.397
Non-invasive 475 (73.8) 18 (81.8) 173 (26)
Invasive 169 (26.2) 4 (18.2) 666 (100)
Total 644 (100) 22 (100)
T2 599 (64.7) 0.0001
Non-invasive 429 (71.6) 170 (52) 327 (35.3)
Invasive 170 (28.4) 157 (48) 926 (100)
Total 599 (100) 327 (100)
T3 563 (62.8) 0.0001
Non-invasive 344 (71.8) 219 (52.4)
Invasive 135 (28.2) 199 (47.6) 334 (37.2)
Total 479 (100) 418 (100) 897 (100)

n: Number of the patients. The total number of the patients provided treatment and radiography is less than the total number of the procedures and radiographs because some patients had one more procedures and radiographs. P<0.05

DISCUSSION

The incidence of patients who had a radiographic procedure was the lowest at the beginning of the pandemic and significantly increased over time. The frequency of patients who had a radiographic procedure was higher (46.6%) at T3 than at T2. Using radiography increased when the number of COVID-19 cases increased. It can be said that the course of the disease did not affect using radiography by dentists. It can be explained as an adaptation of the dentists to the new pandemic conditions.

Intraoral radiography was the most used radiographic technique before the COVID-19 pandemic[10-14] because it has a lower radiation dose and higher image quality than panoramic radiography. It continues to be superior to other radiographic methods in the diagnosis of proximal caries and endodontic treatment planning.[15] Although American Dental Association issued interim guidance recommending avoiding or reducing intraoral radiography when the COVID-19 pandemic begins,[16] MacDonald et al.[2] created a flowchart to guide the prescription of radiographic procedures during the recovery phase of the COVID-19 pandemic. In this flowchart, they recommended that if the patient who needs radiography is infected or suspected infection with COVID-19, only urgent treatment should be performed, and the first imaging method should be panoramic radiography. They suggested providing conventional dental procedures for patients without or suspected COVID-19 infection and the use of conventional radiography including intraoral radiography as the initial imaging modality if the patient does not have a gag reflex. However, these recommendations are prepared to be used in the recovery phase of the COVID-19 outbreak. It cannot be said that the epidemic was in the recovery phase since vaccination was not yet started in Turkey during the periods included in the study. In addition, considering the possibility of people infected with COVID-19 being asymptomatic,[17] dentists should treat each patient as an infected or suspected case, as a basic principle of contamination prevention.

Dental panoramic radiography became the star of dental imaging during the COVID-19 pandemic because of its advantages such as having a lower radiation dose compared to full-mouth periapical radiography and CBCT, no gag reflex, and no aerosol formation[18] but it was difficult to manage urgent treatments using panoramic radiography because it was insufficient to diagnose periapical pathology and pulp-related caries[15] The main areas of using panoramic radiography are clinical suspicion of teeth with periapical pathology, the presence of partially erupted teeth, clinically evident caries lesions, swelling, and clinically suspected unerupted teeth.[6]

Recently, conventional panoramic devices have been developed and panoramic machines with extraoral-bitewing functions have been introduced to the market. The extraoralbitewing function of a panoramic device has an orthogonal view and provides better visualization of the interface contacts of the teeth compared to conventional panoramic radiographs.[19] The popularity of the extraoral-bitewing function of a panoramic machine increased during the COVID-19 period and it was discussed to replace intraoral radiography[2,19,20] and suggestions were presented to improve image quality.[19] However, according to the results of the previous studies, it was contradictory that it was superior to intraoral radiography for caries diagnosis.[21-23] Dave et al.[24] implied that avoidance of using intraoral radiography was inappropriate during the pandemic because the advantages of intraoral radiography cannot be ignored.

According to our results, using CBCT did not increase over time. CBCT indication can be summarized as the situations in which conventional radiographic imaging is insufficient for diagnosis and treatment planning. It should not be an alternative to intraoral radiography due to its high radiation dose.[24] The analyses of our study were consistent with the nature of the use of CBCT.

As shown in studies,[8,10,25,26] patients mostly apply for dental pulpal or periapical lesions and cellulitis or abscess during the COVID-19 period. The most common radiographic findings were found as caries related pulp (66.8%), caries (41%), periodontal disease (36.9%), and periapical infectious lesion (30.5%) during overall pandemic time points on average in this study. Considering that the radiographic findings also reflect the reasons for admission to the hospital, these results were compatible with other studies.[8,10,25,26] While our results showed that periodontal disease increased gradually from 9.1% (at T1) to 45.7% (at T3) and caries gradually increased from 4.5% (at T1) to 50.2% (at T3). This may be related to the disruption of dental treatments due to the pandemic and patients’ need for these treatments was gradually increasing. We should also point out that, since intraoral radiography was rarely used during the COVID-19 period, the radiographic findings reported in our study were limited by the diagnostic ability of panoramic radiography.

The results of this study demonstrated that non-invasive treatments were higher than invasive treatments. Since no urgent triage clinic was established in our hospital and every applicant was accepted for dental interviews, the number of cases requiring urgent dental treatment was not clear. Although invasive dental treatments increased gradually during the pandemic process, dentists did not use radiography in 28% of patients who underwent invasive treatment. Since it took time for the hospital to establish a suitable environment by taking infection control measures in the early days, the interventions changed over time. Surgical and prosthetic procedures were found as the most common treatments among invasive dental procedures. The number of prosthetic treatments was highest at T1 because, at the beginning of the pandemic, unfinished prosthetic treatments were completed. The surgical treatments increased gradually over periods and most tooth extraction was performed. Restorative treatments (12.7%) and other surgical procedures (4.19%) made up rarely and endodontic and periodontal treatments were extremely infrequent (fewer than 2%). It was recommended to extract the tooth causing severe pain to reduce the risk of infection, shorten the treatment period, and minimize re-visits.[27] Restorative treatments were applied mostly by an excavation of caries using handpieces, and by restoration with temporary fillings or glass ionomer.

The results of the study showed that the dentists avoided the use of radiography in elderly patients and the use of radiography in the aged 65 and over patients was found to be lower than in those aged 64 and under. Measures were taken to ensure that the time spent by the elderly patients who were a risky group and had a curfew, in our hospital was as short as possible. The incidence of male patients was found to be higher than females at T1 and T2. In a study evaluating the attitudes of dental patients toward the Mers-A virus, women were found to be more anxious about infection than men.[28]

Limitations of this retrospective study include a lack of clinical variables because the reasons for patient admission were not included in the hospital’s software. The causes for the patients’ admission to the hospital should be noted; however, according to the results of our study, 98% of the patients who had radiographs showed radiographic findings of common dental urgency cases.

CONCLUSION

The rate of patients provided dental radiography was strikingly the lowest at the beginning of the pandemic. Later, a significant increase was found over time. The course of the COVID-19 disease did not affect using dental radiography because it was higher at the time when the COVID-19 cases increased than when the cases decreased. The use of dental radiography in elderly patients was found to be less than in younger patients during the COVID-19 period. Invasive treatments applied to the patients who had radiographs were significantly higher than those who did not. This study demonstrated the changes in radiographic procedures of dental patients at different times of the COVID-19 pandemic.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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