Comparative Evaluation of The Analgesic Effect of Virtual Reality With Topical Anesthesia to Reduce Pain During Administration of Local Anesthesia
Phase: NA
Conditions: Pain
Sponsor: Riyadh Elm University

Cover letter  
 
Comparison between the Analgesic 
Effectiveness of Virtual Reality and Topical 
Anesthesia: A Clinical Study  
 
 
Date of document: April 28th 2021 
 
 
 
 
 
 
 
 

Aim  
The aims of the study are to compare the analgesic and anxiety control effectiveness of virtual 
reality (VR) and topical anesthesia (TA) gel during administration of local anesthesia in adult 
dental patients, and to determine which approach the patients preferred to reduce pain of dental 
injections.  
The null hypothesis was that there will be no significant difference between the effect of virtual 
reality compared to that of topical anesthesia gel in reducing pain during administration of local 
anesthesia injections in adult dental patients.  
Materials and method  
The study was performed in accordance with the Declaration of Helsinki. Twenty-one adult 
volunteers visiting the Riyadh Elm University dental hospital participated in the study, with an 
age range from 22 to 59 years. The procedures were explained to the volunteers in detail and 
an informed written consent form were signed by each participant. IRB Approval no. 
RC/IRB/2019/321 was obtained from the Research Center at Riyadh Elm University, Riyadh, 
Saudi Arabia. 
The study was conducted according to the design of split-mouth randomized controlled double-
blinded trials Each participant was randomly allocated to first receive the conventional 
injection technique under the influence of either topical anesthesia or virtual reality at the area 
of the upper second premolar on one side; and then the other procedure on the contralateral 
tooth after an average of a 10-minute interval. Since it was a split-mouth design, each 
participant served as his/her own control.  
Sample Power Calculation  
Sample power was calculated using the G-Power sample power calculator (Universtat Kiel, 
Kiel, Germany). Given the split mouth study design, an effect size of 0.75 (high effect size) 
was assumed and for a power of 0.95, the total number of participants was determined as 21.  
The inclusion criteria  

• 
Class I of the American Society of Anesthesiologists (ASA) as approved by the ASA 
House of Delegates on October 15, 2014; aged 18 and above, both genders.  
• 
Participants are in good general health, take no medications, and have no 
contraindications to the use of local anesthetic.  
• 
The ability to understand oral and written instructions.  
Protocol for Injection of Local Anesthetic Solution 
The injection was made with 1.8 ml Xylocaine 20mg/ml (DENSPLY Pharmceutical, USA); 
(adrenaline: 1:100.000), delivered in cartridges using a 27 - gauge short needle (0.4 x 25 mm, 
C-K jet) and sterile non-aspirating syringe.  
The anesthetic solution was administered into the buccal sulcus of the treated tooth following 
a standard technique (Handbook of Local Anesthesia, 2013). The syringe was held parallel 
with the long axis of the tooth while the tissue was pulled out. The needle was inserted in the 
mucobuccal fold above the apex of the tooth at 45o with buccal cortical plate of the bone and 
with the gauge facing the bone. A few drops of local anesthetic solution were deposited 
immediately before the needle entered the tissue. After 2 to 3 seconds, the needle was advanced 
apically until the bone was reached and the rest of the solution was administered at a slow rate 
over approximately 1 minute. The needle was then withdrawn gently and slowly.  
Procedure with Topical Anesthesia Gel (TA)  
For each participant, the pulse rate was recorded prior to the procedure using an FDA approved 
pulse oximeter (SantaMedical SM-165 Fingertip Pulse Oximeter, China). The injection site 
was dried and isolated using a cotton roll and a small quantity of the topical anesthesia Iolite 
20% benzocaine (Dharma Research , Miami, USA) anesthetic gel was applied using the end of 
an applicator stick directly at the site of penetration for 15 seconds and then left for 2 minutes 
to ensure effectiveness (Handbook of Local Anesthesia, 2013). All the time periods were 
calculated using Clock App timer available on an iPhone device. The injection of anesthetic 
solution was performed according to the standard technique mentioned above. After the 
injection, the pulse rate was recorded a second time. 
Procedure with Virtual Reality (VR)  

For each participant, the pulse rate was recorded prior to the procedure using an FDA approved 
pulse oximeter (SantaMedical SM-165 Fingertip Pulse Oximeter, China). The virtual reality 
standalone headset used in the study was the 128 GB Oculus Quest® (Facebook Inc. USA). 
The device was loaded with the animated short movie ‘Henry’ (Oculus Story Studio, USA) 
and then properly adjusted around the patient’s head and in front of her/his eyes. The volume 
level was controlled and interpupillary distance (IPD) was adjusted by each participant after 
providing brief instructions. The movie was played for some time prior to administration of the 
injection to enable the participant to interact and get involved with the scene. The next step 
comprised of guiding the patients to turn their heads and adapt with the dentist’s instructions 
while watching the movie. The injection of anesthetic solution was performed according to the 
standard technique mentioned above while the participants continued watching the VR movie. 
After the injection, the pulse rate was recorded a second time. 
Patient Input 
After each procedure was performed (TA or VR), the participants were asked to evaluate the 
degree of pain that they experienced using the Wong-Baker Faces Pain-rating Scale (W-BFPS). 
Official permission was issued from the Wong-Baker FACES Foundation. 
Additionally, each participant was also asked to state his/her preference of delivery system for 
future injections. 
Risk of bias  
To avoid the risk of bias, the following were considered:  
• All participants were blinded to the order of the technique to be used.  
• Both procedures were coded and blinded to the one who did the analysis.  
• Both types of procedures were performed in one session by the same operator to avoid an  
inter-operator variability influence.  
• Special attention was given to keep the syringe out of their line of sight.  
• Regarding communication with the participants, the words (injection shot, pain, and hurt) 
were not used to avoid increasing stress or fears.  

Statistical Analyses  
The normality of the heart rates observed was calculated and was observed to be within 
acceptable limits of Kurtosis and Skew. Therefore, parametric tests were used to analyze 
differences in heart rate. Given the subjective nature of Wong-Baker faces pain-rating scale 
(W-BFPS), non-parametric tests were used to analyze differences in W-BFPS.  
The paired t test was used to compare the heart rates of the individuals between the two 
methods. The Wilcoxon Sign rank test was used to compare the W-BFPS between the two 
methods. The spearman’s correlation was used to check the association between W-BFPS and 
heart rate for each procedure. All tests were performed at p<0.05.  
 
Results 
Analysis of the Descriptive Statistics 
The sample comprised of 21 participants (10 male, 11 female) aged between 25 to 55 years of 
age.  
 
The heart rates of the participants were normally distributed during each procedure (Table 1). 
This necessitated the use of parametric statistics for the analysis of heart rate. 
 
Table 1: Overview of Heart Rates before and after each procedure 
N 
Minimum Maximum Mean 
Std. 
Deviation 
Skewness 
Kurtosis 
Statistic Statistic 
Statistic Statistic Statistic Statistic 
Std. 
Error Statistic 
Std. 
Error 
Heart 
Rate 
Before 
(with 
VR) 
21 
64.00 
101.00 77.7143 
9.64957 
.878 .501 
.675 .972 

Heart 
Rate 
After 
(with 
VR ) 
21 
61.00 
93.00 75.9048 
8.53173 
.240 .501 
-.518 .972 
Heart 
Rate 
Before 
(with 
TA) 
21 
62.00 
109.00 80.4286 12.35950 
.465 .501 
.269 .972 
Heart 
Rate 
After 
(with 
TA) 
21 
64.00 
102.00 79.0000 10.02497 
.705 .501 
.317 .972 
 
 
In order to measure the impact of procedure on heart rate, the heart rates before and after the 
procedure were compared. It was observed that for both procedures the mean heart rate after 
the procedure was slightly lower than mean heart rate before the procedure (Table 2). However, 
the paired t test showed that the difference between the heart rate before and after treatment 
were not significantly different (Table 3). 
 
 
 
 
 
Table 2: Heart rate before and after the treatment for each type of procedure 
Mean 
N 
Std. 
Deviation 
Std. Error 
Mean 
With  
VR 
Heart Rate Before  
77.7143 
21 
9.64957 
2.10571 
Heart Rate After  
75.9048 
21 
8.53173 
1.86178 
Heart Rate Before  
80.4286 
21 
12.35950 
2.69706 

With 
TA 
Heart Rate After  
79.0000 
21 
10.02497 
2.18763 
 
 
Table 3: Significance of difference in heart rate before and after giving the injection for 
each type of procedure 
 
Paired Differences  
t* 
Sig.  
(2- 
tailed
) 
Mean  
Std. 
Deviatio
n  
Std. 
Error 
Mean  
95% Confidence 
Interval of the 
Difference  
Lower 
Upper 
Wit
h 
VR  
Heart Rate 
Before - 
Heart Rate 
After  
1.809
52 
4.02019 
.87728 
-.02044 
3.63949 
2.06
3 
.052 
Wit
h 
TA  
Heart Rate 
Before - 
Heart Rate 
After  
1.428
57 
6.20138 
1.35325 
-1.39426 
4.25141 
1.05
6 
.304 
* Calculated using the paired t test Differences are not statistically significant  
The patients recorded lower heart rates while in VR than in Topical anesthetic as mentioned 
earlier. This was true both before and after the dental injections.  However, the paired t test 
found the differences to be statistically insignificant both before and after dental injections. 
While when gender differences were observed it was seen that the females had a higher heart 
rate compared to the males in each of the four situations. It was observed that these differences 
were statistically significant for TA-before, VR-before and VR-after (Table 4). 
 
 
 
 
 
 

Table 4 – Differences in Heart Rate according to Gender for each procedure 
 
Gender 
Mean 
Std. 
Deviatio
n 
t* 
Sig 
Heart Rate Before (VR) Male 
73.4000 6.09554 
-2.117 
0.048** 
Female 
81.6364 10.8284
1 
Heart Rate After (VR) 
Male 
73.9000 6.62403 
-1.102 
0.311 
Female 
77.7273 9.92059 
Heart Rate Before (TA) Male 
74.9000 9.65459 
-2.118 
0.048** 
Female 
85.4545 12.7778
2 
Heart Rate After (TA) 
Male 
74.1000 7.29459 
-.2.369 
0.029** 
Female 
83.4545 10.3572
5 
**Differences are significant at p<0.05 
 
A paired t test comparing the change in heart rate per procedure with the gender of the 
participants, showed no significance for both genders. 
The patient’s experience of pain with each group was measured using Wong-Baker Faces Pain-
rating Scale (W-BFPS). The Wilcoxon Sign Rank test showed that while 10 of the 21 
participants had a higher W-BFPS with TA when compared to VR, 5 of the 21 reported a worse 
experience with VR when compared to TA. There were six individuals who reported the same 
experience with both procedures (Table 5). These differences were however not significant 
(Z=1.662, sig= 0.096) 
 
Table 5: Comparisons and Ranking of W-BFPS 
N Mean Rank Sum of Ranks 
Z* 
 
Sig 
W-BFPS - VR 
 W-BFPS – TA 
Negative Ranks 5a 
6.50 
32.50 
1.662 0.096 
Positive Ranks 10b 
8.75 
87.50 
Ties 
6c 
 
 

Total 
21 
 
 
a. W-BFPS - TA < W-BFPS – VR 
b. W-BFPS - TA > W-BFPS – VR 
c. W-BFPS - TA = W-BFPS – VR 
*calculated using the Wilcoxon Sign Rank test 
Differences are not statistically significant 
 
In contrast to the heart rate and W-BFPS reading of pain level, when patients were asked which 
method they preferred, a significant majority (Chi square = 14.124, p=0.021) reported that they 
preferred the VR to Topical Anesthesia (Fig 1). 
   
Fig 1: Stated preference of procedure by the population 
 
 
 
 
 
15
4
2
VR
T OP IC A L A NE S T H E S IA
NO P RE F E RE NC E

 
INFORMED CONSENT FORM FOR PATIENT 
This Informed Consent Form is for men and women who attend dental clinic at Riyadh Elm 
University and who we are inviting to participate in research titled Comparison between the 
Analgesic Effectiveness of Virtual Reality and Topical Anesthesia: A Clinical Study 
Part I / Information sheet  
I am Dr May Almugait, working for the dental clinic at Riyadh Elm University. We are doing 
research on effectiveness of virtual reality (VR) in local dental anesthesia. I am going to give 
you information and invite you to be part of this research. You do not have to decide today 
whether or not you will participate in the research. Before you decide, you can talk to anyone 
you feel comfortable with about the research. There may be some words that you do not 
understand. Please ask me to stop as we go through the information and I will take time to 
explain.  
Purpose of the research  
The aims of the study are to compare the analgesic and anxiety control effectiveness of virtual 
reality (VR) and topical anesthesia (TA) gel during administration of local anesthesia in adult 
dental patients, and to determine which approach the patients preferred to reduce pain of dental 
injections.  
Type of research intervention  
This study involves doing local anesthesia twice for maxillary teeth, one with VR device, and 
one with topical anesthesia.  
Voluntary Participation  
Your participation in this research is entirely voluntary. It is your choice whether to 
participate or not. Whether you choose to participate or not, all the services you receive at 

this clinic will continue and nothing will change. You may change your mind later and stop 
participating even if you agreed earlier. 
Procedures and protocol  
Participants will receive dental anesthetic injections bilaterally for the maxillary second 
premolars, within the same visit. One side will be injected under the influence of the topical 
anesthesia (TA) 20% benzocaine, while the other side under the influence of a virtual reality 
(VR) animated movie using an Oculus Quest® device. The order of procedure will be random. 
Heart rates will be recorded prior to and after the injections using a finger pulse oximeter. 
Immediately after each injection, the participants will be directed to rate their pain experience 
using the Wong-Baker Faces Pain-rating Scale (W-BFPS), along with choose which delivery 
system they preferred. 
Duration  
The research takes place over one session for almost 30 minutes. 
Side effects 
It is unlikely to have any side effects during the study. 
Risks  
If any risk appears during the process, the healthcare workers will be looking after you and 
the other participants very carefully during the study.  
Reimbursements 
Your participation is free. You will not be given any other money or gifts to take part in this 
research 
Confidentiality 
The information that we collect from this research project will be kept confidential. 
Information about you that will be collected during the research will be put away and no-one 
but the researchers will be able to see it. Any information about you will have a number on it 

instead of your name. Only the researchers will know what your number is and we will lock 
that information up with a lock and key. It will not be shared with or given to anyone except 
Dr May who will have access to the information. 
Sharing the Results 
The knowledge that we get from doing this research will be published in a scientific journal. 
Confidential information will not be shared.  
Right to Refuse or Withdraw 
You do not have to take part in this research if you do not wish to do so. You may also stop 
participating in the research at any time you choose. It is your choice and all of your rights 
will still be respected. 
Alternatives to Participating 
If you do not wish to take part in the research, you will be provided with the established 
standard treatment available at the dental clinic. 
Who to Contact? 
If you have any questions, you may ask us now or later, even after the study has started. If 
you wish to ask questions later, you may contact Dr May at 0506195647. 
This proposal has been reviewed and approved by the research center in the university 
and given this IRB approval number: IRB Approval no. RC/IRB/2019/321. 
PART II: Certificate of Consent 
I have read the foregoing information, or it has been read to me. I have had the opportunity to 
ask questions about it and any questions that I have asked have been answered to my 
satisfaction. I consent voluntarily to participate as a participant in this research. 
Name of Participant__________________ 
Signature of Participant ___________________ 

Date ___________________________ 
Statement by the researcher/person taking consent 
I have accurately explained the information sheet to the potential participant, and to the best 
of my ability made sure that the participant understands that dental injection will be made 
twice for him/her, one with VR and another one with TA. 
I confirm that the participant was given an opportunity to ask questions about the study, and 
all the questions asked by the participant have been answered correctly and to the best of my 
ability. I confirm that the individual has not been coerced into giving consent, and the consent 
has been given freely and voluntarily.  
A copy of this consent form has been provided to the participant. 
Name of Researcher/ Dr May Almugait 
 
 
 
 
Signature of Researcher /person taking the consent__________________________ 
Date ___________________________