A comparative study on effectiveness of mucosal vibration and topical anaesthetic gel in reducing pain duringadministration of local anaesthetic in paediatric patients.

INTRODUCTION

Pain, is an unpleasant sensory and emotional experience arising from real or potential tissue destruction¹ . Paincan be generated by various factors other than tissue damage, which includes any unpleasant noise or the prick of a needle. The persisting anxiety or feeling of fear acts as a stimulant which exaggeratesthesensation of pain. Anxiety is a matter of concern for Paediatric dentists as the first dental visit leaves a lasting impact and guides the future behaviour of the child towards dental treatment. Moreover, dental anxiety can last till adulthood, and lead to dental neglect. In Pediatric Dentistry, local anaesthetic syringe is the most common cause of anxiety which affects the quality of treatment provided. Hence, pain and anxiety control is animportant consideration in administration of local anaesthetic in a Pediatric dental set up.

Various methods such as topical anaesthetic agents² , distraction techniques³ and reduced speed of injections^4,5 have been introduced to reduce pain, but each proved to have its own clinical limitations. The primary goal of using topical anaesthesia is to minimize the pain and discomfort of needle penetration into the soft tissue. Commonly used topical anaesthetic concentrations are as follows: benzocaine up to 20%; lidocaine solution/ ointment upto 5%; lidocaine spray up to 10%.

Mucosal vibrations induced by vibration stimuli, along with local anaesthetic injection have been initiated asa non-pharmacological technique to reduce pain. It works on basis of Gate Control Theory⁶ , the "Pain gate" can be shut by stimulating nerves responsible for carrying the signals which enable the relief of pain through massage techniques, rubbing, pressure, ice packs, acupuncture, electrical analgesia and the application of vibration. Implementing the concept of vibration, we have used Oral Care Musical Toothbrush for kids. The present study was thus conducted to compare the effectiveness of topical anaesthetic agent and mucosal vibrator during local anaesthetic administration.

MATERIALS AND METHODOLOGY

A cross-sectional study was conducted in the Department of Paediatric and Preventive Dentistry, Krishnadevaraya College of Dental Sciences, Bangalore. Ethical clearance was obtained from the ethical committee board of the institution to start the study. 2 % Lignocaine hydrochloride anaesthetic gel (Systochem laboratories Ltd) and a battery operated electric musical toothbrush for kids™ (Oral Care Solutions, India) were used in this study. (FIGURE I)

Subjects were arbitrarily chosen from outpatient department.

Inclusion criteria:

• Patients with a mean age of 8-11 years who required inferior alveolar nerve block for invasive dental procedures

• No previous dental history

• Frankl’s behaviour rating - positive or definitely positive

Exclusion Criteria:

• Patients with Frankl’s behaviour rating - negative or definitely negative

• Medically compromised patients were excluded from thisstudy.

Written informed consent was obtained from each patient’s parent/ guardian.

Subjects were divided into 3 groups- Group 1 - control (n=10), Group 2 - topical anesthetic gel (n=10) and Group 3 - intraoral mucosal vibrator (n=10).

Group 1- The injection site was isolated and dried using cotton roll and saline is applied using sterile applicator, followed by injection of 1ml of local anaesthetic solution using a 24 gauge sterile syringe.

Group 2- The injection site was isolated and dried using cotton roll, topical Lignocaine hydrochloride anaesthetic gel (2%) was applied using sterile applicator for 30 seconds to the injection site and left for 3-5 minutes after informing the child. Thereafter, 1ml of local anaesthetic solution was deposited using a 22 gauge sterile syringe.

Group 3- The head of the electric toothbrush (Oral care musical toothbrush for kids™) was covered with a cellophane, and was placed in close vicinity to the needle for 1 minute, before and during the administration of 1ml local anaesthetic solution using a 24 gauge sterile syringe. The vibration continued for 15 seconds even after the removal of needle. This had a masking effect and aided in the dissipation of the local anaesthesia solution. (FIGURE II)

As it is extremely difficult to quantify pain in children, one objective and two subjective scales were used in this study. The procedure was explained to every patient in each group before the start, using tell show do technique.

Objective scale - SEM Scales (FIGURE III); Subjective scales - Modified Venham scale (FIGURE IV) and Modified Wong Baker Faces Pain Rating(FPR)Scale (FIGURE V), were used which were modified with common cartoon characters. A set of six cartoon faces were shown to children with varying facial expressions ranging from a smiling face to a sad face. Earlier to the administration of local anaesthesia a brief explanation was given to the child about each face. The child was instructed to choose the face that best described his/her feelings while receiving local anaesthesia.

RESULTS

The collected data both from the subjective and objective scales were entered in the Microsoft Excel Sheet and subjected to statistical analysis. Kruskal Wallis TestANOVA and Man Whitney test was used to compare scores between different groups.

The scores of SEM scale and Doremon pain scale when subjected to Kruskal Wallis Test ANOVA and Man Whitney test gave a p value of <0.001 which was statistically significant. (TABLE I) (TABLE II)(TABLE III) (TABLE IV)

The scores of the Motupatlu anxiety scale when subjected to Kruskal Wallis Test ANOVA gave a p value of 0.157 (TABLE V) and Man Whitney test p value of 0.149. (TABLE VI)

DISCUSSION

Local anaesthesia is the most potent, safest, tested and tried method in the management of pain during the paediatric dental procedures. However, factors such as anxiety related to tryphanophobia and the syringe prick pain experienced by the children during the delivery of local anaesthesia standsasthe biggest challenge to the pedodontist.⁷

In the current study, intraoral mucosal vibrator is being compared to topical anaesthetic gel because of its frequency of chair side use.

In a study done by Vinod Kumar⁸ et al the prevalence of anxiety related to dental treatment was as high as 84.4% among 6-12 year old South Indian children. According to Anju Singh Rajwar⁹ et al the factor that caused the most fear was “feeling the needle injected” and fear of “injections” (38.8% and 37.9% respectively). To achieve most efficient and painless delivery of the local anaesthesia in paediatric dental patients the newer drug delivery systems came up taking advantage of the gate control theory of pain management by Melzack and Wall which suggests that pain can be reduced by simultaneous activation of nerve fibres through the use of vibration⁶ . Inui10 and colleagues have shown that pain reduction due to non-noxious touch or vibration can result from tactile-induced pain inhibition within the cerebral cortex itself and that the inhibition occurs without any contribution at the spinal level, including descending inhibitory actions on spinal neurons.

Many a devices such as VibraJect, Dental Vibe and Accupal have been introduced in the market which functions using the above principle.¹¹

Ali Bagherian¹² et al in his study stated that physical distraction with cotton roll method was moreeffective than routine topical anaesthesia application in reducing behavioural pain reactions in children during administration of local anaesthesia.

E Nanitsos¹³ et al stated extra oral vibration can be used to reduce pain duringdental local anaesthetic administration.

Mangalampally Shilpapriya¹⁴ et al in her study, stated that Dental vibe® (Dental Vibe Inc.) can be a useful accessory device prior to the use of dental injection syringe to alleviate pain and stress of injection both physiologically (based on Gate Control Theory of pain) and psychologically (based on the audible distraction of the device) and has shown to be a beneficial tool in paediatric patient management.

Rahaf Dak-Albab¹⁵ et al also supported the use of DentalVibe as aeffortless and effective method to alleviate pain associated with dental injections as compared to the traditional topical analgesic gels.

Kalpna Chaudhry¹⁶ et al in her study stated that Vibraject provides less pain while giving local anaesthetic injections in comparison to the conventional injection technique in clinical paediatric dental procedures. Visual analog scale (VAS) and faces pain rating scale (FRS) were used for assessment in this study.

Amina¹⁷ et al stated vibration stimulus was found to be effective when applied extra-orally while administering local anaesthesia to children.

But the devices mentioned above are not routinely used in the paediatric dental clinic due to many reasons, cost being the foremost factor.

To counteract these factors, in this study we have used a modified battery operated musical toothbrush was used as an intraoral mucosal vibrating device. The toothbrush had a small accessible head which was covered with cellophane. And to measure the anxiety and pain perceived by the patients, three types of scales were used.¹⁸

SEM scale (FIGURE III) was recorded by the observer i.e. the paediatric dentist delivering the local anaesthesia. Modified Venham picture scale for anxiety¹⁹ and Modified Wong Baker FACES pain rating scale were recorded in regard to the responses of the patient being administered the local anaesthetic.

Considering the popular cartoon characters the scales were formulated- Motupatlu scale for anxiety- Modified Venham picture scale for anxiety (FIGURE IV) and Doremon FACES pain rating scale- Modified Wong Baker FACES pain rating scale ( FIGURE V). The scales were devised keeping the following ideals in consideration.

According to Buchanan²⁰, an ideal anxiety assessment scale should be:

a. Short in length to maximize the response from children and minimize the time for its administration.

b. Include items which are more relevant to the child’s dental experience.

c. Easily grab the attention of the child.

d. Allowed for limited cognitive and linguistic skills.

e. Simple to score and interpret.

The scales were made familiarized to the children before the procedure for their easy understanding. The SEM scale scores recorded showed considerably less anxious behaviour while using an intraoral mucosal vibrator during delivery of local anaesthesia compared to topical anaesthetic gel application and control group. (FIGURE VI)

The Doremon FACES pain rating scale readings recorded as said by the patient after the administration of the local anaesthesia had notable findings between the groups. The group of children in whom the intraoral mucosal vibrator was used had lesser pain sensation during the prick of the needle. (FIGURE VII)

But to the contrary, the results of the Motupatlu scale for anxiety did not have a marked difference amongst the groups. The patients were anxious before administering the local anesthesia in all the groups. The slightly bulky nature of the intraoral mucosal vibrator did not seem to have reduced the anxiety level. (FIGURE VIII)

Results of this study may have marked importance in paediatric dental practice as a compact battery operated intraoral mucosal vibrating device has been proved helpful in reducing pain perceived during local anaesthetic injections.

CONCLUSION

The battery operated intraoral mucosal vibrating device serves as a useful, handy and cost effective chair side method to reduce pain during local anaesthesia administration in paediatric patients.

And the novel modified cartoon scales have a better understanding by the paediatric crowd, as they can relate to the characters in the scale better than the prototype figures.

Acknowledgements - not applicable.