dentaires à l'ère de la télémédecine : une étude pilote
S. Patterson, B.Sc., DDS, MPH
C. Botchway, BDS, LDSRCS (Eng), MSC (Uni Lon) DDPHRCS (Eng)
L'étude pilote permettait de comparer les données récoltées au moyen, d'une part,
de méthodes d'examens dentaires visuels traditionnelles et, d'autre part, d'une caméra
intrabuccale. Les données étaient respectivement regroupées dans un environnement
scolaire et transmises à distance par télémédecine.
Aux fins de l'étude, 137 écoliers ont été examinés suivant les méthodes
traditionnelles. Deux mois plus tard, 32 enfants ont été sélectionnés au hasard et
réexaminés en un seul jour au moyen d'une caméra intrabuccale et de la télémédecine.
Les unités de mesure utilisées étaient deft/DMFT.
Le fossé de comparaison entre les données récoltées à l'aide des deux méthodes
d'examen ne s'est révélé être que minime. Les taux de recoupement entre les méthodes
variait de 89 à 100 p. 100.
Dans les régions recluses et mal desservies, la télémédecine peut permettre
d'identifier avec précision les troubles bucco-dentaires et servir de véhicule de
consultation à distance entre les spécialistes, les praticiens dentaires généralistes,
les hygiénistes dentaires et les patients individuels.
Mots clés MeSH :
dental care; rural health services;
© J Can Dent Assoc 1998; 64:806-10
Le présent article a fait l'objet d'une
révision par des pairs.
[ Methods and Materials | Results | Discussion
| Conclusions ]
Telehealth is a joining of telecommunications technology
with health delivery. Using interactive video, audio and computer technologies as the
information transfer platform, medical information can be transmitted over long distances
between urban centres and under-serviced rural areas.1
Through the use of conventional telephone lines,
microwaves or satellite link-ups, physicians at a central medical hub can examine and
treat patients at multiple satellite locations.2 Telehealth can be used for
situations in which (1) physical barriers prevent the ready transfer of information
between the health care professional and patient, and (2) information availability is key
to proper medical management.3
Much of the framework for telehealth technology is
currently in place. Telephones have proven to be economical and reliable for data
transmission.4 Many dental offices are already equipped with intraoral cameras,
video monitors and computers,5 and digital imaging systems6 are
becoming more widespread.
The University of Alberta Telehealth Centre
is the collaborative effort of an interdisciplinary health committee. The Telehealth
Centre is currently linked to the Two Hills Health Care Centre in eastern Alberta, and
steps are being taken to expand telehealth sites to other communities in the province.
Many health disciplines including dentistry could make use of this technology in
delivering clinical diagnostic services to remote areas that are unaccessed by dental
specialists or, in some cases, general dental practitioners.
|Fig. 1: Dental hygiene students operating telehealth
equipment at Two Hills site.
Many dental public health programs are involved in oral
health screenings in school settings throughout the province. This level of programming
requires moving equipment and qualified staff to remote locations. It does not allow for
direct consultations with dental practitioners since public health dental hygienists or
assistants complete this work. As telehealth technology spreads across the province,
dental programs could potentially utilize this mode of communication for consultations,
diagnostic appointments, data collection and post-treatment evaluation.
This pilot study investigated whether the use
of telehealth communication technology and intraoral cameras for completing visual oral
health screenings would be comparable to visual screenings in the traditional school
setting. Implementation of such technology could potentially reduce the need for
highly trained health workers to commute to and from remote areas for purposes of
screenings, oral diagnosis and referral. In addition, if images transmitted via telehealth
technology correspond to those seen in person, then consultations between specialists in
central locations and health care workers in remote areas could be carried out.
[ Top ]
Methods and Materials
The University of Alberta Telehealth Centre was
established utilizing the LinkCarer System, which was developed by Hughes Training Inc.,
an Arlington, Texas, company. LinkCarer has a modular design that allows for different
levels of equipment and capability that are open, upgradeable and easily integrated. The
system ranges from full diagnostic treatment to triage/monitoring, and includes fully
interactive audio and video components that transmit consultations, medical databases,
real-time ultrasound and moving images (ECGs), heart, lung and blood flow sounds,
radiographs, EKGs, EEGs and other diagnostic study records, live video pictures of
affected body parts and tissues, and precise still images.
The link between the Telehealth Centre and Two Hills is
via telephone lines, although capacity for satellite, microwave and cellular transmission
is also a possibility for future connections. A coder-decoder device (CODEC) digitizes and
compresses the video and audio signals and transmits images using a relatively small,
narrow bandwidth. There are two 20-inch monitors with standard resolution, one for viewing
the local site and one for viewing the distant site. The sites are connected by a two-way
audio system. Both sites have document cameras with graphic capabilities for presenting
still images only and single-chip cameras, which can be panned, tilted and zoomed locally
or remotely by a touchscreen controller. The touchscreen controller is used to control all
of the operations except the computer. Each site has a VCR, a computer, and diagnostic
instruments. A patient camera at the remote site allows for a greater degree of
magnification and detail resolution in transmitting live images.7 The intraoral
camera system utilized was the Revealr system by Patterson Dental.
The subjects for the pilot were children who attended Two
Hills Elementary School and who had received parental consent for the regular public
health dental screening. A total of 137 children were screened at the school by a
registered public health dental hygienist and a registered dental assistant (who acted as
recorder), both of whom had been trained by the regional dental officer. This initial
screening was to provide baseline data using the traditional method of data collection in
the school. The indices used were deft/DMFT. An intraoral mirror, a portable chair and a
light source were utilized. Appropriate infection control procedures were followed. All of
the 137 children were given a letter of consent for the second screening explaining the
purpose of the telehealth screening and the methods employed.
Two months later, the second screening was carried out on
32 randomly selected children in each grade who had received parental consent for the
telehealth screening. After time for travel and equipment set up at the Two Hills Health
Care Centre, the children were screened using the intraoral camera. Of the 32 screenings,
only 27 data results were analyzed as five children had lost teeth in the two months since
the school screening, thus altering the deft/DMFT scores from the original screening.
Three dental hygiene students and the regional dental
officer conducted the telehealth screenings. One student operated the intraoral camera
while another assisted with the children. The same portable light source, intraoral
mirrors and infection control procedures were employed as in the school screenings. The
images picked up on the intraoral camera were transmitted to the Telehealth Centre, where
the same dental hygienist and dental assistant who had participated in the first screening
received and interpreted the images using deft/DMFT as their indices.
The telehealth equipment involved two TV monitors (Fig. 1). One monitor displayed the camera image being sent to the other
location and the other monitor displayed the image being received from the distant site.
Audio communication was also available. All verbal communication was clear and
understandable. If any difficulty in visualizing a particular surface of a tooth was
noted, requests for the camera to be moved were made by the recorders at the Telehealth
The results of the first and second
inspection were compiled through a spreadsheet, charting both the deft and DMFT. The score
and number of errors were analyzed for percentage agreement. Chi-squared tests indicated
that there were no significant differences between the two screening methods, and
statistically, the results were similar.
| Table I
|Screening Results for the Primary Dentition (deft
|Number of Teeth
||School Screening Number of Children
||Telehealth Screening Number of Children
|To be extracted:
| Table II
|Screening Results for the Permanent Dentition
|Number of Teeth
||School Screening Number of Children
||Telehealth Screening Number of Children
| Table III
|Inter-method Agreement and Reliability for School
and Telehealth Screenings
|Primary to be extracted
[ Top ]
The initial baseline data obtained from the visual oral
health screenings in the school were compared with data obtained from the telehealth
screenings for primary tooth decay, primary teeth needing extraction, and primary restored
teeth (deft index), and for permanent tooth decay, permanent teeth missing due to caries
and permanent restored teeth (DMFT index). Only small variations occurred between the two
methods (Tables I and II). Chi-squared tests were used at p<0.05. The groups showed no
statistically significant differences.
Kappa statistics8 were applied to the data to
determine agreement in excess of that expected through chance (Table III). Perfect
agreement existed for the three categories of primary teeth to be extracted, permanent
teeth missing and permanent teeth filled. For both the primary and permanent teeth with
decay groups, the kappa statistic showed moderate agreement, and for the group in which
primary teeth were to be filled, the agreement was very good. The percentage agreement
between the traditional school visual screening and the telehealth screening was very
close, and in those areas where variation occurred, the kappa agreement showed moderate to
very good agreement.
Overall, the screening results between the
traditional and telehealth methods of performing dental screenings were similar, with no
difference found in the areas of detection of primary teeth to be extracted or filled, and
permanent missing teeth.
[ Top ]
Though not new to medicine, telehealth technology has not
become part of every day health care or dentistry. Technical immaturity, economic
feasibility and legal considerations may be partly responsible for its restricted role.
Cost-effectiveness is also an important consideration in evaluating its potential use.
Capital equipment costs for the telehealth system are very high and will vary from
facility to facility. The cost of the LinkCarer System, which can have many equipment
configurations, can range from approximately $40,000 to $130,000. For dental screenings to
be cost-effective using this system, it would likely be necessary for the telehealth
infrastructure to be already present. Alberta Health is currently considering expanding
the telehealth equipment to more sites within the province, which would allow a
"piggyback" effect for completing dental consultation and screening services
without having to purchase and install equipment solely for that purpose. If a health
facility or clinic purchased telehealth equipment, then the capital costs could be passed
on in the form of user fees for the clinicians or groups utilizing the equipment.
This study showed that a number of factors contributed to
the cost of each process. Both types of screenings involved a team consisting of a dental
hygienist and a dental assistant. Extra personnel were required at both the school and the
telehealth facility to help with getting the children to and from the screening site.
Set-up time was similar in both settings. Although the telehealth screening time per child
was initially a little slower, experience with the system eventually allowed for the two
types of screenings to take about the same amount of time.
There were, however, differences between the two methods
that would impact on any cost-benefit analysis. The school dental screenings involved the
cost and time of travel for the dental staff to go to the school. For the telehealth
screenings, the costs involved transporting the children from the school to the health
facility (which in this case were assumed by the school), the cost of having a trained
person operating the intraoral camera (which may or may not be a person with dental
training), and the cost of using the telehealth equipment.
There was no cost to the public health dental program for
utilizing the Two Hills Health Centre equipment, as both groups belong to the Lakeland
Regional Health Authority. If a system were to be used on a regular basis, and the capital
and transmission costs factored into any user fees, then the investment would eventually
be covered. Hopefully, the individual cost of using such equipment would not be too
prohibitive. Further studies are needed to investigate the very real issue of the economic
viability of this technology.
The merits of the telehealth screening method include the
fact that it is a potentially mobile system that can be manipulated by trained, non-dental
personnel. The telehealth system also allows for clear communication of visual and audio
data over great distances, all in real time, thereby significantly reducing travel time
and costs for both practitioner and patient. (It can also accommodate patient assessments,
history taking, transmission of digital data, radiographs and stilled images, either in
real time or on videotape for later use.) The technology could also be used for real time,
pre-authorization for dental insurance benefits.
Potential weaknesses of this method include the cost of
equipment, especially in start-up cases. As well, for clinicians unaccustomed to using an
intraoral camera, some preparation time and practise in visualizing the teeth and oral
cavity is required. Training of the distant health care worker in the use of the intraoral
camera is also necessary. It was noted, for example, that care needs to be taken during
the transmission of the visual image to ensure that correct colour tone and brightness are
achieved. Furthermore, if the screening is to be completed without the use of explorers,
there will be an accompanying loss of detail in the data recorded as no tactile
information will be transmitted. The system was found to be most effective in identifying
missing and filled teeth, probably because these two areas are easily visualized and do
not require tactile sense to detect. Another reason for this may be that there were very
few teeth in these index categories. The percentage agreement in these categories was
predominantly on sound teeth. Less agreement was observed in the detection of decay.
No explorers were utilized in the study. It is possible
that the dental hygienist was so accustomed to using an explorer for detecting decay that
she found using only visual detection less definitive or reliable than detection using
tactile sensation. In addition, visual detection of decay may have been hindered due to
the unfamiliarity with intraoral viewing of teeth. These factors could have introduced
variability in the recording of carious lesions and would have potentially decreased her
intra-examiner reliability. If concern existed in a clinical setting about the loss of
detailed diagnostic information as a result of not having the remote inspections completed
with the use of an explorer, both digital radiographs and standard films could be easily
transmitted to enhance the information being collected.
The population pool of the study was small
due to time constraints on that school day and to the fact that five children out of the
32 had lost some of their teeth, which impacted on their deft score. Their inclusion in
the study would have inappropriately reduced the statistical accuracy of the telehealth
screenings. In retrospect, it would have been prudent to reduce the time interval between
the first and second screenings to avoid the potential for change in the deft/DMFT status
as a result of exfoliation or dental treatment.
[ Top ]
This pilot study indicated that the data collected using
the telehealth system was similar to that of the traditional, intraoral visual screenings
currently completed in public health dental programs. The telehealth system enables
reliable, remote observation of oral conditions such as decayed, missing and filled or
extracted teeth. It is used to transmit oral images to dental hygienists, dentists or
specialists in urban centres for consultation or educational purposes (for example,
communication with dental students in satellite locations). Although digital imaging is
becoming more widespread and available in dentistry, the use of telehealth technology in
remote dental screenings will depend on the existence of telehealth equipment throughout
the province. The extensive cost of establishing telehealth sites will require financial
support and a utilization across a broad spectrum of health care disciplines. Although
networking of this technology may require some initial cost and implementation time, once
fully developed, the system could offer a simple and reliable alternative to remote dental
Acknowledgment: Special recognition and thanks
go to the following dental hygienists and assistants for their invaluable assistance in
carrying out this project: Shari Holland, Cory McQuaig, Patrick Miklos, Jennifer Parsons,
Afae Rodwell, Sandy Tillotson and Sherry Kokotailo.
The cooperation and support of the Lakeland Regional
Health Authority, Two Hills Health Care Centre and Two Hills Elementary School was greatly
Dr. Patterson is director of continuing dental
education in the Department of Oral Health Sciences, University of Alberta, and director
of the Dental Public Health Centre, University of Alberta.
Dr. Botchway is a clinical assistant professor
in the Department of Oral Health Sciences, University of Alberta, and is a member of the
Dental Public Health Centre, University of Alberta.
Reprint requests to: Dr. S. Patterson,
Department of Oral Health Sciences, Dentistry/Pharmacy Centre, University of Alberta,
Edmonton, AB T6G 2N8.
The authors have no declared financial interest in any
company manufacturing the types of products mentioned in this article.
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