Table 1 Characteristics of the included studies and summary of results (N = 16)

1. Patterson and Botchway 1998 [29]

Canada

J Can Dent Assoc

Pilot study

Cross-sectional (observational)

Dental screening

•137 screened via traditional method

•Among them, 32 telehealth screened after 2 months,

•27 analyzed as 5 children lost teeth in between the 2 months

N/A

2 Elementary Schools

•Telehealth screenings conducted by dental hygiene students and regional dental officer. Images were transmitted to the Telehealth Centre and screened by the same dental hygienists and dentist who had conducted the initial school screenings. Telehealth screenings were compared to baseline data

LinkCarer System: fully interactive audio and video components via telephone lines

Effectiveness of telehealth technology versus traditional screenings,

screening time,

screening cost

•Deft/DMFT indices score and number of errors in spreadsheet compilation

•No significant difference between two methods and agreement between these ranged between 89%-100%

•Perfect agreement was found for primary teeth to be extracted, permanent missing and permanent filling; very good agreement for primary filled; and moderate agreement for both decay groups

2. Scuffham and Steed 2002 [30]

United Kingdom

J of Telemedicine and Tele care

Non-randomized trial for 12 months

Economic evaluation of teledentistry

25

Mean 46

(16–49)

Patients requiring a referral to a specialist in 2 general practices Questionnaires: 14 patients; 18 specialists and 15 GDPs

•Specialist consultation via videoconference compared to specialist outreach visits and patients’ hospital visits at two general dental practices

Videoconference: ISDN connection,

Teleconsultation

Costs fixed, direct, indirect

•Questionnaires completed by patients, GDPs, and specialists

•Additional cost for national health service (€36 and €44/patients at both dental practices) compared to outreach visits, cost savings (€270 and €1.54 at both dental practices) compared with hospital visits

•Indirect cost savings were higher with teledentistry (79%) and outreach visits (84%) compared to hospital visits

•Cost-savings for the NHS, however patients (travel) and general dental practitioners incurred some new costs (time)

3. Ignatius et al 2010 [31]

Finland

J of Telemedicine and Tele care

Observational descriptive

Diagnosis and treatment plans

49:

25 professionals: 18 dentists, 2 dental hygienists and 5 nurses;

24 patients

N/A

Patients requiring prosthetic or rehabilitation treatment Central hospital and regional health centers

•Effectiveness of videoconferencing for accurate diagnosis and making treatment plans for rehabilitation treatment

Videoconferencing using standard commercial units via an IP network, at bandwidths of 762 kb/s–

2 Mb/s

Number of diagnosis and treatment planning

Satisfaction of dentists and patients

•Dentist examination by videoconference;

•Questionnaires

•Videoconferencing equipment functioning was reliable and led to smooth consultations in 24 out of 27 cases

•Patients were satisfied. The greater the distance, the higher the satisfaction (p < 0.01)

•Professionals were also satisfied

4. Herce et al 2011 [32]

Spain

J Oral Maxillofac Surg

Evaluative pilot study (multicenter, longitudinal, descriptive)

Evaluation of presurgical management of impacted third molar pathology

97

(52♀ 45♂)

35.07 ± 13

Patients with impacted third molars with no contraindication for extraction under local anesthesia;

university hospital and 4 rural dental clinics

•Presurgical management of third molar pathology: dentist examination via PC, information is gathered and sent to Oral and Maxillofacial surgery unit

Store-and-forward telemedicine system (SFTMS)

Clinical effectiveness of SFTMS as a preoperative management and planning tool; waiting intervals; patient satisfaction

•Evaluation of teleconsultations by the maxillofacial surgeon, patient examination and clinical information compared to clinical data registered by PC dentist

•Days between visit to PC dentist and day of inclusion on surgical wait list

•Patient satisfaction surveys

•The SFTMS is effective tool in the presurgical management of patients

•Statistically significant shorter waiting intervals achieved by SFTMS (3.33; 95% CI = 2–4.65 days) in comparison to conventional referral system (28; 95% CI = 24.51–29.6 days) (p < .001)

•Avoidance of unnecessary hospital visits

•No statistical significance in cancellations between telemedicine and traditional system (p = 0.76)

•Patient satisfaction: 77.3% very satisfied and 22.3% just satisfied

5. Salazar-Fernandez et al 2012 [33]

Spain

J Oral Maxillofac Surg

Quasi-experimental

Analytical

Clinical study

Management of temporomandibular

Joint (TMJ) Disorders patients

1052

E: 342

(276♀ 66♂)

C: 710

(587♀ 123♂)

E: 38.3

C: 41.08

TMJ Disorders patients in 10 primary care hospitals, Northern Seville

•Using telemedicine system (images and clinical records examined by 2 distant maxillofacial surgeons) as a method for the selection, diagnosis, and treatment of patients with TMJ disorders at remote site compared to conventional hospital consultation

Store-and-forward telemedicine system

through the Andalusian

Public Health System Intranet (TMJ, ISDR-B, and Frame Relay/ADSL networks) to the e-mail account

1. Clinical effectiveness (rates of diagnosis of myofascial syndrome and/or internal derangement Wilkes Stages I-II-III, internal derangement Wilkes Stages IV–V, other arthropathies; resolved teleconsultations, number of second teleconsultations; rate of referrals to hospitals; mean treatment delay; reduction of number of first hospital visits,

2. Cost (lost working hours/patients)

3. Patient satisfaction

•X-ray images, clinical information, standard

•Questionnaires satisfaction surveys

•No statistical differences in clinical effectiveness were found between the two groups (standard vs telemedicine)

•Rates of pathologies requiring assistance in the TMJ unit (10.2% vs 11.6%)

•Patients requiring non-surgical treatment (89.7% vs 88.4%)

•Resolved consultations (88% vs 74.5%; p = 0.07)

•Second teleconsultation (0.8% vs 4.6%, p = 0.07)

•Mean cost of lost working hours per patient (16.8 Vs 32.24; p < .01)

•Mean waiting time was significantly lesser in teleconsultation (2.3 days; 95% CI: 2.2–2.4) compared to standard system 78.6 days; 95% CI: 77.0–80.1) (p = .00)

•63% patients were very satisfied, 36.7% satisfied, and only 1 patient was unsatisfied

6. Birur et al 2015 [34]

India

J of ADA

Descriptive Observational study

Screening

3440

Cohort 1 (targeted screening by

health care workers) = 2000

Cohort 2 (Opportunistic screening by dental professionals) = 1440

(> 40)

Adults with high prevalence of oral cancer risk habits

Primary health center

•Effectiveness of a mobile-phone based remote oral-cancer surveillance program to detect lesions and capture interpretable images

•Dental screening by general dentist and health care workers and specialist diagnosis (reference standard)

Mobile health application for remote oral cancer surveillance

(Oncogrid)

Lesion detection,

Capture of interpretable images of the oral cavity

•Risk evaluation questionnaire,

•Image detection by specialist,

•Histological evaluation using WHO classification

•In the targeted cohort showed 45% concordance with specialists and the opportunistic cohort showed 100% concordance

7. Marino et al. 2016 [35]

Australia

Journal of Telemedicine and Telecare

Cost-analysis

Screening and caries assessment

Cost evaluation

100

N/A

Residential aged care facility in

rural areas of the Australian state of Victoria,

•Comparing the cost and benefits of face-to-face patient examination assessments conducted by a dentist with two teledentistry (asynchronous and real time)

Teledentistry

Costs–fixed, direct, indirect

•Costs

•Cost for Teledental asynchronous = AU$32.35/resident (lowest);

•Cost for teledental real time = AU$41.28/resident

•Cost for face-to-face examination = AU$36.59 /resident

8. Wood et al 2016 (I) [36]

USA

J Oral Maxillofac Surg

Cross sectional

Assessing perceived utility and demand for the application of telemedicine for

improved patient care

226 GP and 41 OMS

NA

Practicing Virginia Dental Association members on an e-mail list (approximately

2,200)

Virginia Society of Oral Maxillofacial Surgery

members on an e-mail list (approximately 213)

•Determine the perceived utility and demand for the application of telemedicine

Teledentistry

Perceived utility and demand for the application of telemedicine

•Two distinct questionnaires, one for the non-surgical dental practitioners (GPs) and oral and maxillofacial surgeons (OMS)

•Rural patients had a longer time from referral to OMS consultation (P = .003) and traveled longer distances (P < .0001);

•GPs moderately agreed to the benefits of telemedicine while OMS were mostly neutral

•GPs agreed to refer more patients if teleconsultation was used. More referrals would influence OMSs' decision to offer teleconsultations

•GPs had neutral opinion on the reliability of teleconsultations, whereas OMS said they would use it if provides equally good consultations as face-to-face consultations

9. Wood et al 2016 (II) [37]

USA

J Oral Maxillofac Surg

Retrospective study

Assessing patients for surgical treatment under

Anesthesia

(triage)

335

(331 ♂ [99%])

Mean 32.5 years (SD = 9.31 years)

Data were collected from a retrospective patient

chart review from telemedicine consultations performed

between the Virginia

Commonwealth University Medical Center and the Virginia Department of Corrections from May

2008 to June 2014

•Efficiency and reliability of telemedicine consultations for preoperative assessment of patients

Data from telemedicine consultations

Chief complaint, history of current illness, and

medical history by ‘‘face-to-face’’ video interview,

examination by intraoral

camera,

Radiographic examinations,

Physical examination assisted by a nurse or surgical

technician at the remote site,

estimated cost savings over the 6-year period on comparing with the previous study data at the National Institute

of Justice

•Dental electronic health charts

•92.2% of the time practitioners successfully used the data collected for diagnosis and treatment plan

•95.9% patients were given an accurate diagnosis and treatment plan

•99.6% patients were accurately triaged

•98% patients were given adequate medical assessments and underwent surgery as planned

•Cost saving was substantial at $134,640 for 6 years

10. Petruzzi and De Benedittis 2016 [38]

Italy

Oral Surg Oral Med Oral Pathol Oral Radiol

Cross-sectional Observational study

Diagnosis

96

65 rural

N/A

339 clinical images relating to the 96 cases sent by eighty clinicians (general dental practitioners, hygienists, and physicians) and patients, or their relatives

92/96 patients (96%) attended Oral Medicine unit for a clinical examination

In 45 cases a biopsy was performed

•Clinical images were spontaneously sent to the authors’ smartphones via WhatsApp. Images were reviewed by two oral medicine experts. The patients then underwent an oral mucosa examination at the clinic, where all biopsied lesions were examined histopathologically by an independent pathologist

WhatsApp messenger mobile application version 2.10 or higher. One examiner used an iPhone 4 s (3.5″ screen) and the other a Galaxy S III (4.8″ screen)

Agreement rates between TM oral medicine expert’s diagnosis and clinicopath assessment

•Percentage calculation

•316 photos (93%) were good quality photos

•Telemedicine impressions by the two oral medicine experts agreed with the clinicopathologic assessment for 82% cases, with an inter-rater reliability of 100%

•Agreement rate for traumatic cases was 95%, for infectious lesion 96%, for preneoplastic/neoplastic disorders 71%, for autoimmune 82% and for non-pathological conditions was 67%,

11. Purohit BM et al. 2016 [39]

India

Journal of Public Health Dentistry

Cross-sectional

study

Screening/

dental caries assessment

139

(62♂, 77♀

12 years

School children from same racial/ethnic

group located in the region of

the outreach health centers of Bhopal district

•Standardized video recording of the oral cavity for caries assessment

A Sony Xperia smart phone with an 8-megapixel camera, 720 * 1,280-pixel resolution, and LED flashlight was used to standardise video recording of the oral cavity. The video files were stored in MP4 format, with a duration of 40 s and a file size of 60 MB, respectively

Mean DMFT

•Visual tactile and video-graphic assessments

•Mean DMFT was 2.47 ± 2.01 by visual tactile and 2.46 ± 1.91 by video-graphic assessment (p = 0.76)

•Fair agreement between visual tactile and video-graphic assessment (intraclass correlation coefficient = 0.56)

•Video-graphic assessment: Sensitivity and specificity values were 0.86 and 0.58 respectively. Positive and negative predictive values were 0.90 and 0.48 respectively (area under the curve = 0.69)

12. Estai M et al. 2017 [40]

Australia

Australian Health Review

A cost-minimization analysis

Cost analysis

Screening

2.7 million children

5–14 years

Australian school children

(Australian Bureau of Statistics)

•Compare the costs of teledentistry and traditional dental screening approaches

Teledentistry

The fixed costs and the variable costs,

including staff salary, travel and accommodation costs, and cost of supply

Direct and indirect costs

•Costs

•Total estimated cost of teledentistry model = $50 million

•The fixed cost of teledentistry = $1 million and fixed cost of staff salaries = $49 million

•Total annual saving with the teledentistry was $85 million. Estimated staff salary saved = $56 million, and the estimated travel allowance and supply expenses avoided = $16 million and $14 million respectively

•Teledentistry cost an average of $19 per child, compared to $41–187 per child for traditional screening, depending on the distance from residence

13. Teoh J et al. 2018 [41]

Australia

Telemedicine and e-health

A model-based analysis was conducted to determine

the potential costs of implementing teledentistry at the hospital

Assess the use of Teledentistry

367 Teledentistry appropriate consultations

NA

Royal Children’s Hospital

for rural and regional patients

•Assess the use of Teledentistry in delivering specialist dental services

•Conduct an economic evaluation by building a decision model to estimate

•Costs and effectiveness of Teledental consultations compared with standard consultations at the hospital

Teledentistry

Timely consultations (whether the

patient presented within an appropriate time according to the recommended schedule)

•Review of dental records of orthodontic or paediatric dental consultations at the hospital

•Cost-effectiveness analysis comparing teledentistry with the traditional method of consultation

•241(65.7%) consultations were timely

•The cost saving with teledentistry consultation was A$136.95 per appointment more compared to hospital consultations

•With teledentistry, there will be a societal cost saving of $3,160.81 for every timely cleft lip and palate consultation and hospital consultations could have freed up 36.7 days of clinic time

14. Tynan et al. 2018 (I) [42]

Australia

BMC Health services research

A mixed method comparison study

Impact and experience

of an integrated oral health program utilising tele-dentistry and Oral Health Therapists (OHT)

27 residents (10♂, 17♀)

One focus group (5) + 8

Interviews (gender non-specified)

Mean 77.09 (34–101) 82.4 (44–97)

A total of 252 audits were complete across nine residential aged care facilities

(111 audits at facilities with integrated oral health and 141 audits at facilities without integrated oral health Out of the 27 participants, 7 were from residential aged care facilities with integrated oral health program and 20 were

from facilities without program

Participants for qualitative data included 5 nurses from facilities with integrated program and 8 nurses from facilities without the program

•Comparison between facilities with and without an integrated program by Audits, GOHAI surveys, 1 FG + 8 interviews

Tele-dentistry

(a dentist

for a remote real-time oral examination if required) The

OHT, specifically trained in manipulating the intraoral

camera, can simultaneously communicate with a remotely

located dentist

Comparison facilities with and without integrated oral health program

•Audit

•Qualitative content analysis

•GOHAI questionnaires

•Audit comparison of facilities with integrated oral health program implemented and with integrated programs showed better compliance with oral health standards at integrated facilities. (More satisfactory oral health plans, 89.2% vs 75.2%; p = 0.005)

•Mean GOHAI score 50.6 ± 5.1 vs 51 ± 5 indicating poor oral health quality of life

•Thematic analysis showed improvements in importance placed on oral health, better access to services and training, and decreased disruption in facilities with integrated programs

15. Tynan et al. 2018 (II) [43]

Australia

Aust. J. Rural Health

A quality improvement study incorporating

pre- and post chart audits and pre- and post consultation

with key stakeholders, including staff and residents,

expert opinion on cost estimates and field notes

were used

Screening via the oral health therapist

and teledentistry appointment

116

N/A

One regional and three rural residential aged

care facilities situated in a non-metropolitan hospital

and health service in Queensland

•Audits comparison between facilities with and without an integrated program

•Perceived impacts on staff and residents

•Cost comparison

Teledentistry

Comparison facilities with and without integrated oral health program

•Number of appointments avoided at an oral health facility

•Feedback on program experience by staff and residents

•Compliance with oral health care plan implementation

•Observations of costs involved to deliver new service

•Increase up to 96% of residents with an appropriate oral health care plan was observed

•Positive feedback was received from staff, residents, and their families

•Staff and managers reported increased awareness of residents’ oral health needs and prevention requirements; improved access to resources for oral health management; and savings from reducing the need to transport residents to an oral health facility

•Reduced disruption to high care residents;

•Positive cultural change in staff toward oral health care

•Initial screenings by the therapist resulted in potential problems being identified and addressed earlier than in the past

16. Vinayagamoorthy et al. 2019 [44]

India

Aust. J. Rural Health

An observational cross‐sectional study

Preventive screening of oral potentially malignant

Disorders

131

64.1%♀ + 35.9%♂

Mean (SD) age of

37.34 years (11.31)

Primary care setting in Udupi District, Karnataka, South India

•Clinical oral examination followed by photo capture of five areas of the patients' mouth

A Samsung Note 2 mobile phone

with an 8‐megapixel camera and a display with a resolution

of 720 × 1280 pixels with autofocus (Samsung, Seoul,

South Korea) was used

The photo messaging feature of the WhatsApp messenger

(Version 2.17.190; WhatsApp, Mountain View, CA, USA)

Both the examiners examined

the images in their mobile phones (Android

smartphones with a display size of 5.50″ and a display resolution

of 1080 × 1920 pixels) separately with the display brightness

at 50%

Reliability measures for the use of a photo messaging

service in diagnosing oral potentially malignant disorders, as compared to the

clinical examination

•Reliability of an exact diagnostic match of lesions between the examinations

•Inter‐examiner and intra‐examiner reliability of the clinical oral examination and photographic examination

•Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value

•Agreement between the two examiners for the diagnosis based on photo messaging

•When lesions were classified as normal or abnormal, the reliability between diagnoses for Examiners 1 and 2 based on photo messaging and clinical oral examination was 0.68 and 0.67, respectively

•Sensitivity for examiners 1 and 2 were 98.5% and 99.04%, respectively, and specificity was 72% and 64%, respectively

•When the agreement between photo messaging and clinical oral examination for an exact diagnostic match was evaluated, the reliability was 0.59 and 0.55 for Examiners 1 and 2, respectively

•Sensitivity for Examiners 1 and 2 were 98.1% and 98.7%, respectively, and specificity was 64% and 52% respectively