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High-quality photos are critical for the remote diagnosis of dental trauma and thus are beneficial to the prognosis. The quality of the images obtained using a cell phone depends on the level of dental and photography knowledge of the person who is taking the photos.
This study aimed to determine the efficacy of photography education in improving images used for the remote diagnosis of dental trauma.
The subjects comprised 30 laypeople and 30 dentists who were randomly assigned to 15 subgroups with 2 subjects in each. Each subject was asked to take photos of their own anterior teeth and those of their partner on the assumption that an accident occurred using both an iPhone 4s and iPhone 6. Education about how to take an appropriate photo of the anterior teeth for teleconsultation purposes was then provided, after which photos were taken again. Photos were assessed by a dentist for their usefulness in diagnosis.
This study analyzed 965 photos: 441 taken by laypeople and 524 taken by dentists. Photos taken after providing education had significantly higher scores for all assessment items than those taken before education (
Both laypeople and dentists might find photography education useful for when they are taking photos to be used in teleconsultations. The type of cell phone does not significantly affect the usefulness of such photos.
The World Health Organization has recently released a statement emphasizing the use of appropriate digital technologies for public health [
Rapid progress in information technology has resulted in successful implementation and testing of the electronic submission of clinical images for remote consultations in most medical and surgical subspecialties [
Devices used to provide remote oral care services include oral video cameras (intraoral image capturing devices), digital single lens reflex (DSLR) cameras, and cell phones with built-in cameras [
Cell phones are highly portable, have high-resolution cameras, and are now almost ubiquitously used by people of all age groups. Continuing developments have allowed for such devices to be used not only for telecommunication but also to provide multiple computer-like communication functions including text, photo, and video transfer, as well as internet access. Different types of remote consultation or treatment based on the use of cell phones are currently being investigated in the field of telemedicine [
However, the quality of the images obtained using a cell phone depends on the level of dental knowledge of the person who is taking the photos and the imaging conditions [
This study investigated differences in image quality according to who photographed the traumatized tooth (dentist vs laypeople), the effect of receiving photography education (before vs after), and what model cell phone was used (including different numbers of camera pixels).
This clinical research was approved by the institutional review board of the dental hospital at Yonsei University (number 2-2012-0025). The subjects consisted of 60 Korean adults (30 laypeople and 30 dentists) selected from 62 volunteers. The laypeople comprised 21 males and 9 females ranging in age from 21 to 39 years (28.67 [SD 4.20] years), while the dentists comprised 14 males and 16 females who ranged in age from 26 to 37 years (30.74 [SD 3.21] years). The inclusion criteria were being older than 20 years, able to operate the camera on a cell phone, having continuous anterior dentition (including any prosthesis and orthodontic brackets), and signing the consent form for the experiment.
The subjects were randomly arranged into 15 subgroups with 2 subjects each, and they were asked to take photos of themselves and their partner using both an iPhone 4s (0.3-megapixel front camera, 8-megapixel rear camera, Apple), and iPhone 6 (1.2-megapixel front camera, 8-megapixel rear camera, Apple) before and after receiving photography education (
Summary of experimental design.
We assumed that injuries had occurred in the subjects because of an accident. Subjects were encouraged to freely take photos of the maxillary anterior area including 4 incisors and 2 canines by using the functions of autofocusing, blurring, white balance, focal length, and resolution provided by the cell phone, with the built-in front camera and the default camera app. They were then asked to take photos of their colleagues’ teeth using the same methods but with the built-in rear camera.
Photography education was then provided by an experienced dental hygienist, face to face, to every subject with the following contents: how to take photos from frontal and occlusal views, how to take a photo in which all 6 anterior teeth appear, how to use a retractor to expose soft tissue, how to adjust the focus, and how to adjust the camera settings according to the protocol proposed by Park et al [
The captured images were assessed twice with a 1-week interval on a desktop computer (LG, screen resolution 1920×1080 pixels, 8-bit color depth) by a single dentist in the Department of Advanced General Dentistry at Yonsei University.
After all the photos had been collected, errors that appeared frequently during the experiment were analyzed and images of frontal and occlusal views were evaluated. Frequent errors included retraction failure and incomplete frontal and occlusal views. Each photo was evaluated as either good or failure, and the relationships between this categorization and the frequency of errors were evaluated by the dentist (
Examples of photos that were appropriate and inappropriate for the initial assessment.
The two assessments meant that the assessment score for each tooth type was on a 10-point scale. The highest score was used when multiple photos of the same type were assessed. The central incisors, lateral incisors, and canines were assessed separately against the items listed in
Assessment items.
Category and finding | Suggested situation | |||
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Optimal focus | — | |||
Movement present | — | |||
Exposure | — | |||
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Shape | Crown fracture | |||
Position | Displacement | |||
Alignment | Displacement | |||
Bleeding spot with pink color | Pulp exposure | |||
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Shape | Crown fracture | |||
Position | Displacement | |||
Alignment | Displacement | |||
Bleeding spot with pink color | Pulp exposure | |||
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Gingival sulcus | Gingival bleeding | |||
Integrity | Laceration | |||
Color | Hematoma | |||
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Gingival sulcus | Gingival bleeding | |||
Integrity | Laceration | |||
Color | Hematoma |
Data were analyzed using SPSS Statistics version 25.0 (IBM Corporation). The intrarater reliability was assessed using Cohen kappa. Paired
Each photo was assessed by the dentist twice. The kappa indexes for intrarater reliability were .764 and .728 for the general assessment and the assessments of hard tissue and soft tissue, respectively.
This study analyzed 965 photos: 441 taken by laypeople and 524 taken by dentists. Frontal view photos were taken by all subjects before and after receiving education. In contrast, occlusal area photos were taken by only 16 subjects (4 laypeople and 12 dentists) which were further taken by all subjects after education, and so these photos were not suitable for performing comparisons.
In the group of laypeople, photos in which the retraction was evaluated as being appropriate were taken by 8 subjects with the front camera and 12 with the rear camera by the partners before receiving education, increasing to 23 and 28, respectively, after receiving education. In the group of dentists, photos in which the retraction was evaluated as being appropriate were taken by 20 subjects with the front camera and 19 with the rear camera by the partners before receiving education, increasing to 28 and 30, respectively, after receiving education.
Photos taken after education had significantly higher scores than those taken before education with the exception of the evaluation item of optimal focus for the iPhone 6 front camera (
This study assessed the use of cell phones for teleconsultations in dentistry. It was found that the photo scores were significantly higher for those taken by dentists than by laypeople for most of the evaluated items and for those taken after receiving education compared with beforehand except for one item in the iPhone 6 group with the front camera. The iPhone 6 did not have overwhelming advantages over the iPhone 4s.
There were common errors observed in the photos. Frontal view photos—and not occlusal view photos—were taken by both laypeople and dentists, and many images were taken without appropriate retraction. However, after participants received instruction in photography, the error rates in both the layperson and dentist groups were markedly reduced. Moreover, there were statistically significant differences in most of the evaluation categories between before and after receiving the education. These observations support the usefulness of providing image-taking instructions to both laypeople and medical staff in photography education sessions on appropriate methods for dental trauma teleconsultation using cell phones.
While the dentist group received higher evaluation scores both before and after the education compared with the laypeople group, there was no significant intergroup difference in the score for the item of shape in occlusal photos of hard tissue after the education using either the iPhone 4s or iPhone 6 (
According to the in vitro study of Park et al [
There are several reports of satisfactory results being obtained when using cell phone apps for caries screening and traumatic dental injuries [
In a study of the usefulness of an app in diagnosing dental trauma, Mohan et al [
However, a cell phone camera should be viewed as a complementary tool for use in teleconsultation, since images of dental trauma patients taken using cell phones may be different from images taken at a dental clinic. Moumoulidis et al [
This study was subject to several limitations. First, the study involved healthy subjects rather than actual trauma patients. Second, instead of evaluating images that had been taken with a cell phone and then transferred, the imaged files were analyzed directly on a computer screen. Third, we used iPhone 4s and iPhone 6 cell phones for the teleconsultations since most related studies have used iPhone devices, and so it might be worthwhile to repeat the experiment using Android cell phones in the future. Future studies should address the limitations of this study including trying to mimic actual traumatic events.
Photography education is effective for both laypeople and dentists. Further developments of teleconsultation using the camera built into a cell phone require an optimal photo-taking protocol that should include the following factors: (1) obtaining frontal and occlusal images with proper retraction applied so that 6 anterior teeth and soft tissue are clearly visible, (2) photos should be taken by another person, and (3) the rear rather than the front camera should be used in order to optimize the image quality.
Comparison of the quality of photos taken before and after education.
Comparison of the quality of photos taken using front and rear cameras.
Comparison of the quality of photos taken with the iPhone 4s and iPhone 6.
Comparison of the quality of photos taken by laypeople and dentists.
ubiquitous health care
digital single lens reflex
This research was supported by a grant from the Korea Health Technology Research and Development Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Republic of Korea (grant number: HI18C0474).
None declared.