Telediagnosis of Oral Disease

Jair Carneiro LEÃO1,2
Stephen R. PORTER1

1Department of Oral Medicine, Eastman Dental Institute for Oral Health Care Sciences, University of London, London, England
2Departamento de Clínica e Odontologia Preventiva, Universidade Federal de Pernambuco, Recife, PE, Brasil

Braz Dent J (1999) 10(1): 1-60 ISSN 0103-6440

| Introduction | Material and Methods | Results | Discussion | Acknowledgment | References |

Computers have increasingly found application in dentistry over the past 15 years, but at present there has been no investigation of the application of the Internet for distance diagnosis purposes in oral medicine. As a consequence, the objective of this article was to determine the acceptability to patient and clinician of the distant diagnosis of common orofacial diseases using the Internet. The study group comprised 20 patients who attended the Oral Medicine unit of the Eastman Dental Institute and Hospital, London, UK, for the diagnosis and management of oral mucosal diseases. Digital images of each patientís oral mucosal lesion were captured and stored on a personal computer and later transmitted via the Internet to a distant site. Patients were asked to complete a self-administered questionnaire detailing their opinion of the use of an intra-oral camera and a group of clinicians were asked to compare and contrast the original and transmitted images. The majority of patients found the procedure of recording images of their mouth very comfortable, were happy to view the inside of their mouths, and found the procedure generally useful in understanding their clinical problem. The clinicians were often not able to differentiate between the original and transmitted image but were able to accurately diagnose the patientís oral mucosal problems in 64% of the instances. The results of the present study suggest that telediagnosis of orofacial disease may be a feasible prospect.

Key Words:  telemedicine, oral disease, intra-oral camera, diagnosis.


    Computer technology has increasingly found application in clinical dentistry, particularly as computer hardware becomes cheaper, more widely available and more effective. In 1991, only about a quarter of all UK dental practices had appropriate computers (Eaton, 1994); however, the number of dental practices using computers is likely to increase significantly following the introduction of electronic data transmission of treatment schedules (Hammond et al., 1993). In addition, the rapid acceptance of the Internet and the World Wide Web as means of communication (Sund and Rinde, 1995) suggests that increasing numbers of medical and dental clinicians will use computers for many applications in clinical practice.
    To date computers have principally been employed in clinical dentistry for tasks such as recording patient appointments (Zimmerman et al., 1986), treatment schedules (Hammond et al., 1993) and other administrative duties (Abbey, 1987; Lee et al., 1995). There is, however, a great need to develop appropriate methods for distance diagnosis using computer technology.
    Telemedicine (telecommunication-supported medicine) permits doctors to investigate and treat patients via videoconferencing and electronic information exchange. Instead of patients being transported to the site of a clinician (or vice versa), digitized patient information is transmitted to the clinician thus saving time, transport and money.
    Use of telemedicine systems has varied between medical specialties. Radiology is probably the main user of telemedicine technology: digitized radiological images can be electronically distributed to distant clinical settings, for example Saudi Arabia to the USA (Goldberg et al., 1994).
    In addition, studies have also been undertaken in psychiatry (Kavanagh and Yellowlees, 1995; Baer et al., 1995), pathology (Nagase, 1995; Eusebi et al., 1997), rheumatology (Pal, 1997), orthopedics (Delaplain et al., 1993), dermatology (Norton et al., 1997; Perednia, 1997; Kvedar et al., 1997), otorhinolaryngology (Crump and Driscoll, 1996), oncology (Kunkler et al., 1997) and HIV medicine (Frank et al., 1997).
    In the UK, medical clinicians have assessed the possible benefits of communication between primary and secondary health care providers using ISDN (Integrated Systems Digital Network)-based technology. The ISDN-2 system employed in most of these evaluations permits digitized data to be transmitted rapidly at a bandwidth of 128 kilobytes per second and thus allows still and moving color images to be transmitted in real time, without visual degradation with distance.
    Evaluation of ISDN-2 technology in the practices of dermatology, histopathology and psychiatry suggest that such off-the-shelf technology may be of some clinical benefit in the diagnosis of disease by specialist health care workers at sites distant from the patient and primary health care worker (Malone et al., 1997). The ISDN-2 system does not provide appropriate bandwidth for real-time transmission of moving images, but this can be overcome by the use of additional ISDN lines.
    Although ISDN technology is readily available worldwide, the necessary hardware is still expensive in relation to the cost of a personal computer (PC). In contrast, the hardware and software required for the use of the Internet is inexpensive and all countries have ready access to it. The aim of this study was thus to determine the possible acceptability of recording and transmitting clinical images of patients with orofacial diseases via the Internet, and thus develop the application of the use of this network in the distant diagnosis of oral disease.

Material and Methods

Study Patients

    The study group comprised 20 patients (12 males, 8 females; median age 45 years, range 23-72 years) referred to the Oral Medicine unit of the Eastman Dental Institute for Oral Health Care Sciences, London, UK for the diagnosis and management of oral mucosal disease.

Electronic capture of clinical images

    At the end of their initial clinical consultation in the Oral Medicine unit, digital images of each patientís oral mucosal lesion were captured using a ĎClear-VUí (Digital Services (DPS), Welwyn, UK) digital camera equipped with an extra-oral lens and stored on a 486 DX2 66 Hertz personal computer equipped with 8 MB RAM and a Super VGA monitor (Trust Computers, Hertford, England). The software employed to capture images was Screen Machine II (FAST Multimedia AG, Kronberg, Germany).

Transmission of clinical images

    All the captured images were also stored on videotape using a Panasonic NV SD40B Videorecorder (Matsushita Electronic Industrial Co., Ltd., Osaka, Japan), and patients were able to view the captured images on a 14 inch color monitor (KV M1401U; Sony Corporation, Slough, England). Photographs of each lesion were additionally recorded and printed using a high quality image printer (Mavigraph VP 1200 EPM; Sony Corporation, Slough, England) and stored in the patientís clinical notes.
    Following electronic capture, clinical images were sent via the Internet as attached files. In addition, details of the patients (e.g., clinical history and clinical examination, without name or address) were recorded on a standardized electronic letter and sent separately via the Internet again as an attached file. The digitized and transmitted images were received on a DELL P90t PC (Dell Computer Corporation, Berkshire, UK) equipped with an 11-inch Super VGA screen. The original images were also transferred to an identical personal computer for later evaluation.

Patientsí acceptability, image capture and viewing of clinical images

    All patients were asked to complete a self-administered questionnaire detailing their opinions of the use of the intra-oral camera, and the acceptability of viewing images of their oral lesions.

Acceptability of transmitted clinical images for diagnosis of oral disease

    To determine the acceptability of the transmitted clinical images in the diagnosis of oral mucosal disease, a group of judges were asked to compare and contrast consecutively the original and transmitted clinical images. The judges were 12 dental-qualified clinicians and 2 non-clinicians. All judges were asked to score the quality of the original and transmitted images and to distinguish between the original and transmitted images, using a score system of 1 (inadequate) to 5 (excellent). These dental-qualified judges (1 Registrar grade and 11 Senior House Officer grade) were also asked to provide a provisional diagnosis of each patientís clinical problem based upon the data provided in the accompanying standardized letter, and the transmitted clinical image. The provisional diagnosis of the clinical judges was compared to that of the attending consultant (SRP) in the oral medicine clinic.


Patient acceptability of use of intra-oral video camera

    The majority (85%) of patients indicated that the reason for recording images of their oral lesions had been fully explained by the attending clinician, and 75% of patients found the procedure of recording images of their mouths comfortable and not unpleasant. Twelve of the 20 patients were happy to view images of their oral lesions (Table 1A) and 13 (65%) indicated that this aided their understanding of their clinical problem (Table 1B). Just under half of the patients reported the procedure to be time-consuming (Table 1C). No patient had any concerns about the procedure and all were agreeable to have the procedure repeated.

Opinions of clinicians and non-clinicians of the original and transmitted clinical images

    Both clinically-qualified and non-qualified judges could not differentiate between the original and transmitted images in 71.1% of cases, suggesting that the original and transmitted images are of similar quality.
    The judges regarded almost all images as of suitable quality for diagnosis, the mean scores being above 4, however the clinical judges correctly provided appropriate provisional diagnosis in only 64% of cases. Clinicians faired poorly on images number 19 and 20; only 40% providing the correct diagnosis. This may correlate with the poor quality of those two images. Nevertheless as the clinicians adequately interpreted most of the other images, the precise reasons for their poor diagnosis of some lesions remain unclear.


    Computers have had many applications in clinical dentistry, but to date their possible use in teledentistry has not been fully investigated. The ability for clinicians to communicate quickly and effectively is important to ensure appropriate patient management (e.g., the early diagnosis of oral malignancy), and subsequent education of the primary health care staff. To date the distant diagnosis by electronic means has principally been employed in medical specialities such as radiology, dermatology pathology and psychiatry; there is little data on the practical aspects and benefits of this to dentistry.
    The present study is the first to investigate the practical aspects of teledentistry, i.e. acceptability to patients and the ability of clinicians to provide provisional diagnosis of orofacial disease when provided with images and clinical details transmitted from a distant site via the Internet.
    In the present study only one of the twenty study patients had previously had images of their orofacial tissues captured electronically, nevertheless after appropriate explanation by the attending clinician the majority of patients believed that they understood why they were having the procedure and generally did not find it to be time consuming or uncomfortable. Only 12 (60%) of the patients regarded their viewing of the images of their orofacial disease as acceptable, but 13 (65%) did believe that it provided a fuller understanding of their orofacial problem. All images were transmitted during working hours as attached files, thus there was a delay of up to 30 minutes in the images arriving at the second PC. There was, however, no notable degradation of the images as a result of transmission, as both clinical and non-clinical judges could not reliably distinguish between the original and transmitted images.
    The clinicians could generally make a differential diagnosis based upon the electronic data transmitted. Indeed, despite the clinical judges being relatively junior clinicians, they provided the appropriate provisional diagnosis in 64% of instances. It is thus evident that if this method of communication was to be employed in regular clinical use, it is likely to be of practical benefit, permitting secondary health care staff with appropriate information to give primary health care staff the appropriate advice. The personal computers and videocapture card used in this study were, deliberately, not especially complex or expensive models, and thus likely to be within the financial constraints of general dental practitioners likely to have intra-oral digital cameras. Thus as the cost of such equipment continues to fall, the potential for distant diagnosis of orofacial disease will increase.
    Despite the aforementioned data suggesting that the digital recording of images of orofacial disease and the transmission via the Internet is a practical and effective means of communication, not all images were adequately interpreted by clinicians. In addition, although the clinical images and patients details were transmitted separately there is a need for some method of encryption to ensure the data cannot be read by non-involved parties, if data is inadvertently transmitted to the wrong site. The clinical judges did not view the transmitted images at the time of their transmission (i.e., interpretation was not in real-time). Information sent via the Internet generally does not pass directly from the sender to the recipient, instead as found in this study it can take considerable time before the message reaches the recipient, thus this means of transmission of clinical data may be inappropriate when a clinical opinion, based upon transmitted data, is required urgently.
    In conclusion the results of the present study suggest that teledentistry using the Internet may be a practical means of communication between dental clinicians and hence improve the management of patients with orofacial disease. There is, however, a need to undertake a more detailed study of a wider variety of orofacial diseases and compare the efficacy of transmission of clinical data via the Internet with other technologies, such as ISDN, that permits rapid transmission of a large amount of data, hence, real-time diagnosis of disease.


Jair Carneiro Leao is supported by a grant from CAPES-Ministry of Education, Brazil (BEX2783/95-9).


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Correspondence: Dr. Benjamin Peretz, Department of Pediatric Dentistry, Hadassah Faculty of Dental Medicine, P. O. Box 12272, Jerusalem, Israel. Fax: 972-2-6435610. E-mail:

Accepted November 26, 1998
Electronic publication: September, 1999