Effect of Buzzy Bee in Reducing Pain Perception during Local Anesthesia in Children: A Split-mouth Crossover Study

Abstract

Background

Diverting the child's mind from unpleasant stimuli is the major technique employed, allowing a more comfortable and less stressful dental experience. This study aims to assess the effectiveness of a noninvasive externally cold and vibrating pain-reduction device in reducing pain perception during intraoral local anesthetic (LA) administration in children.

Materials and methods

A sample of 39 children aged 6–10 years scheduled for bilateral dental procedures requiring local anesthesia were recruited for the crossover study. Two visits were scheduled for procedures at each side, with an intervening washout period of 7 days. The study sample was randomly allocated to two groups, alternatively receiving the intervention at each visit. Participants' subjective assessments of pain were measured using the Wong–Baker facial expressions rating scale. The pain that was witnessed was documented using the sound, eyes, and motor (SEM) scale, and parents were asked to assess their child's pain tolerance from 1 to 10. The pulse rate and behavior levels based on the Frankl behavior rating scale (FBRS) were also recorded.

Results

Subjective pain scores reduced significantly in the test group compared to the control group at both visits (p < 0.001). Pain scores of both parental (p < 0.05) and SEM scale (p < 0.001) demonstrated significant reduction in the test group only at the first visit. No significant differences were noted in pulse rates and behavior levels.

Conclusion

The externally cold and vibrating pain-reduction device appears to effectively reduce pain perception during intraoral LA administration in children.

How to cite this article

Vishwanathaiah S, Maganur PC, Areshy RA, et al. Effect of Buzzy Bee in Reducing Pain Perception during Local Anesthesia in Children: A Split-mouth Crossover Study. Int J Clin Pediatr Dent 2025;18(11):1390–1396.

Introduction

The term “pain” refers to a range of unpleasant sensory and emotional experiences that may or may not be linked to real or possible harm to tissues.¹ Among the leading theories proposed for pain modulation is the gate control theory. The brain's ability to regulate the transmission of pain signals via a gating mechanism in the dorsal horn of the spinal cord is further supported by this finding. According to this model, nonnoxious stimuli such as pressure, vibration, or changes in temperature stimulate larger diameter nerve fibers that effectively close the gate to nociceptive (pain) signals, thereby reducing the perception of pain. On the basis of this knowledge, several methods which include application of topical anesthetics, buffering the local anesthetics (LAs), warming anesthetic solutions, application of distraction techniques, usage of computer-controlled injections, and altering the rate of infiltration to reduce dental pain have been suggested.^2,3

In addition to pain management, handling children presents a unique challenge for dental professionals. Uncooperative behavior could further hinder their treatment tolerance and extend the duration of procedures. A decline in the tolerance of treatment and an increase in the duration of treatment period are common hurdles that dentists must navigate through while treating children.³ Capturing the child's focus to the procedure, as well as engaging their cognitive abilities, is essential for fostering a positive relationship between the child and the dentist. Thus, proper pain management plays a pivotal role in successful behavior management.⁴

Behavior management through nonpharmacological measures is considered a best practice especially in pediatric care as it not only helps in addressing behavioral challenges but also plays a crucial role in pain relief. These measures include voice control, modeling, distractions, hypnosis, and many more.^5,6 Diverting the child's mind from the unpleasant stimuli is the major technique employed, allowing a more comfortable and less stressful dental experience.⁷ A measure that could incorporate both the distraction as well as the pain reduction at the injection site could be a useful tool in pediatric dentistry.⁸

While pediatric dentistry has advanced considerably, injections still evoke a major concern. The challenge of managing the discomfort associated with it persists, largely due to the absence of an established standardized technique. Hence, interventions that are simple, quick to implement, economical, and reusable become more valuable. One such intervention is Buzzy Bee (MMJ Labs, Atlanta, Georgia, United States), which is a bee-shaped noninvasive, reusable, inexpensive tool designed to relieve pain. It consists of a battery-powered vibrating unit connected to removable ice wings to provide a cold sensory experience. Dr Amy Baxter, a pediatric emergency physician based in the United States, is credited for its creation.⁹ It is operated based on gate control theory outlined by Melzack and Wall in 1965 and the descending inhibitory mechanism.⁷ The Buzzy device can be a promising alternative with practical advantages.⁷ The effectiveness of using Buzzy Bee in pediatric population was shown in previous studies, where Buzzy Bee demonstrated superior performance compared to conventional methods.^7,9,10

While assessing the effectiveness of any technique to reduce pain perception, it is essential to assess the pain perceived by an individual at three different stages of administration of LA—during needle insertion, during solution deposition, and following tissue delivery to obtain an overview of the technique. Nevertheless, only a few studies have reported the pain perception during solution deposition.^8,11,12 Furthermore, evaluating parents' perception in conjunction with the child's pain experience may serve as a reliable proxy to determine the child's overall experience. In consideration of these knowledge gaps, the current investigation aimed to determine if a noninvasive pain reduction device may alleviate discomfort during delivery of LA.

Materials and Methods

Study Design

Following the recommendations of the 2010 statement—extension to randomized crossover studies to guarantee transparent reporting by the Consolidated Standards of Reporting Studies (CONSORT), a split-mouth crossover study was carried out.¹³ A CONSORT diagram (Fig. 1) illustrates the flow of participants.

Fig. 1:

CONSORT diagram

Ethical Considerations

The study obtained ethical clearance from the Institutional Ethics Committee of the College of Dentistry at Jazan University in Jazan (REC 46/06/1253). The trial commenced after obtaining informed consent in writing from the parents of the participants. The detailed protocol of the trial was explained to the parent or legal guardian prior to enrolling the participants. The trial was conducted adhering to the ethical standards outlined in the Declaration of Helsinki (1964) and its latest revisions.

Sample Size Estimation

The sample size was calculated based on assumptions reported in a previous study.¹⁴ The formula used for sample size calculation is as follows:

$$n=\frac{2S_p^2{\left[Z_{1–\frac{\alpha }{2}}+Z_{1–\beta }\right]}^2}{{\mu }_d^2}$$

$$\text{ where, }=S_p^2=\frac{S_1^2+S_2^2}{2}$$

Z_1−α/2 = 2.58 for 99% confidence interval.

Z_1−β = 0.84 for 80% power.

S₁ = 1.54 (standard deviation in device group).

S₂ = 2.14 (standard deviation in conventional group).

µ_d = 3.14 (difference in mean pain scores between two groups).

The sample size estimated was nine in each group. After adding 20% of attrition rate to compensate sampling loss, the minimum sample size required for this study was estimated to be 12 participants in each group for this study. But the final sample size included in the study was 19 in each group.

Participant Selection

Inclusion Criteria

Children in the age of 6–10 years, with proper parental consent, scheduled for bilateral dental procedures requiring LA administration in either maxillary or mandibular arches and demonstrating positive or definitely positive behavior in the pretreatment assessment with a score of 3 or 4 on the Frankl behavior rating scale (FBRS) were included.

Exclusion Criteria

Children with symptoms of irreversible pulpitis and dentoalveolar abscess, known allergy to LAs, and who were mentally or medically compromised were not allowed to participate in the study.

Study Setting

A total of 38 children visiting the outpatient clinic of the Department of Pediatric and Preventive Dentistry, Jazan, were enrolled in this study.

Test Intervention: Buzzy Bee™

This research used a vibrating device, Buzzy Bee™ (Pain Care Labs, United States), during the LA injection technique. The device was coupled to a precooled (up to 50°C) gel icepack containing water, sodium polyacrylate, and mixed isothiazolinones.⁸ During the surgery, the Buzzy Bee™ device was placed at the ramus of the mandible (Fig. 2) or the zygomatic arch (Fig. 3), allowing for LA infiltration at the appropriate arches. Prior to extraoral administration, participants were permitted to play with the gadget, and the intervention was introduced using the “Tell-Show-Do” strategy.

Fig. 2:

Buzzy Bee for mandibular infiltration

Fig. 3:

Buzzy Bee for maxillary infiltration

Standard Care

The usual treatment was the standard LA infiltration approach, in which 5% lidocaine anesthetic gel is administered topically, followed by the injection of 2% lidocaine 1:80,000 adrenaline solution in a cartridge for both mandibular and maxillary infiltration (Figs 4 and 5).

Fig. 4:

Standard technique for maxillary infiltration

Fig. 5:

Standard technique for mandibular infiltration

Procedure

Using a computer-generated random sequence, a research sample of 19 people was recruited and divided into two groups, group A and group B. At the initial visit, group B received standard care, whereas group A received standard care with the test intervention. This was followed by a washout period of 7 days. At the second visit, group B received standard care with the test intervention, while group A received standard care. Each participant alternated between the right and left sides of the allocation on each visit, receiving the intervention on one side and serving as the control on the other.

After being seated in a dental chair, the patient was asked to assess their level of discomfort following an injection by choosing a face from the Wong–Baker scale (WBS), and a pulse oximeter was attached to their index finger to monitor their pulse rate. The demographic details of the participants were recorded before the commencement of the trial. All the procedures were performed by the principal investigator.

Outcomes

Pain

The subjective and objective assessment of pain was the primary outcome of this study.

The Wong–Baker facial expressions rating scale: This measure is employed to evaluate pain subjectively.¹⁵ Each of the six facial expressions on the scale has a numerical value between 0 and 6, which represents the level of pain. The scale's scores were used to categorize pain: 0–4 indicated mild pain, 4–6 indicated moderate pain, 6–8 indicated severe pain, and 8–10 indicated intolerable agony.

Sound, eyes, and motor scale: This objective scale was used to assess the pain and behavior based on a video filmed before and after anesthesia using a mobile phone. The pain was evaluated on a scale of 0–3 in each component—sound, eyes, and motor (SEM)—based on signs of comfort, mild discomfort, moderate pain, and pain, summing up to a total score of 0–9.¹¹

Parental scale: Parents evaluated their child's pain tolerance using this observational measure. Based on responses like no tolerance, tolerance with sobbing, with tears just, without expression, and with a grin, the pain tolerance was measured on a scale of 1–10, with higher scores denoting more tolerance.¹¹

Pulse Rate and Frankl Behavior Rating Scale

The secondary outcomes such as pulse rate and Frankl behavior rating were assessed for this study. The pulse rate was recorded “before,” “during,” and “after” LA administration. The “before” values were recorded over a 15-minute period before LA administration to account for fluctuations, and the final mean was computed. The “after” values were recorded 1 minute after the injection. The FBRS was used to evaluate the child's behavior prior to, during, and following anesthesia. The cooperation and responsiveness of the child throughout the dental surgery are assessed using this 4-point ordinal scale (one being certainly negative, two being negative, three being positive, and four being absolutely positive).¹⁶

Statistical Analysis

The statistical analysis was performed using Statistical Package for Social Sciences (SPSS 20 for Windows, SPSS Inc., Chicago, United States). The Chi-squared test was used to analyze distribution of participants across the groups based on age, gender, and accompanying person. The normality of data was assessed by the Shapiro–Wilk test. The Mann–Whitney test was used to perform intergroup comparisons of patient behavior, parental scale, and intensity of pain, while the unpaired t-test was used to analyze intergroup comparisons of pulse rate.

Results

Distribution of the participants in relation to age and gender among the two groups (conventional LA vs Buzzy Bee technique) was described in Table 1. A very high statistically significant difference was observed for intensity of pain after the procedure during the first visit (p < 0.001), and in the second visit, a high statistical significance (p = 0.002) was observed for WBS scores after the procedure, with a greater median score of “4” reported in groups A and B (conventional technique group), as shown in Tables 2 to 4.

Table 1:

Demographic characteristics of study population

Sl. no.	Parameters	Group A N (%)	Group B N (%)	p-value
1	Age
	7–8 years	8 (42.1)	10 (52.64)	0.36
	9–10 years	11 (57.9)	9 (47.36)
2	Gender
	Male	9 (47.36)	7 (36.84)	1
	Female	10 (52.64)	12 (63.16)

Table 2:

Comparison of pulse rate during local anesthesia administration

Visit	Parameter	Group A (Mean ± SD)	Group B (Mean ± SD)	p-value
First visit	Pulse rate
	Before anesthesia	93.48 ± 9.19	94.97 ± 10.6	0.652
	During anesthesia	97.52 ± 9.5	98.78 ± 11.6	0.716
	1 minute after LA administration	95.52 ± 10.46	97.26 ± 10.77	0.617
Second visit	Pulse rate
	Before anesthesia	100.4 (92.8, 105.9)	96.2 (91.2, 102)	0.397
	During anesthesia	101 (92, 108)	98 (92, 105.5)	0.672
	1 minute after LA administration	97 (88.5, 102)	99 (90.5, 102)	0.907

Table 4:

Comparison of intensity of pain during local anesthesia administration

Visit	Parameters	Group A [Median (Q1, Q3)]	Group B [Median (Q1, Q3)]	p-value
First	WBS
	Before the procedure	0 (0, 0)	0 (0, 0)	NA
	After the procedure	4 (4, 6)	2 (2, 4)	<0.001**
Second	WBS			NA
	Before the procedure	0 (0, 0)	0 (0, 0)
	After the procedure	2 (2,3)	4 (2, 6)	0.002*

NA, not applicable; WBS, Wong–Baker scale; Significant at 0.05 level; *Significant at 0.01 level; **Significant at 0.001 level

The parental perception scores demonstrated a statistically significant difference in the rating of pain tolerance between groups at the first visit (p = 0.03). However, at the second visit no statistically significant difference between groups was observed, as described in Table 5.

Table 5:

Comparison of intensity of pain during local anesthesia administration

Visit	Parameters	Group A [Median (Q1, Q3)]	Group B [Median (Q1, Q3)]	p-value
First	Parental scale	8 (4, 9)	9 (8.5, 9.5)	0.03*
Second	Parental scale	9 (8, 9)	9 (7.5, 9)	0.754
First	SEM
	Sound	1 (0, 1)	0 (0, 1)	0.312
	Eyes	1 (1, 2)	1 (0, 1)	0.003**
	Motor	1 (0, 1)	0 (0, 0)	0.001***
Second	SEM
	Sound	1 (0, 1)	1 (0, 1)	0.528
	Eyes	1 (0, 1)	1 (0, 1.5)	0.597
	Motor	0 (0, 1)	1 (0, 1)	0.11

*Significant at 0.05 level; **Significant at 0.01 level; ***Significant at 0.001 level

On analyzing the SEM scores, a highly significant difference was observed for the “eyes” score (p = 0.003) during the first visit across the groups with a median score of 1 in both. A very high statistically significant difference (p < 0.001) was obtained for the “motor” scores [1(0,1), 0(0,0)] with no pain reported in the Buzzy Bee group during the first visit, as shown in Table 5.

Statistically significant difference was not obtained during analysis of pulse rate and patient behavior during the procedure, as described in Tables 2 and 3. However, there was a mild increase in pulse rate during LA administration in the Buzzy Bee group during both visits without any statistical significance.

Table 3:

Comparison of patient behavior during local anesthesia administration

Visit	Parameters	Group A [Median (Q1, Q3)]	Group B [Median (Q1, Q3)]	p-value
First	FBRS
	Before anesthesia	4 (3, 4)	4 (3.5, 4)	0.738
	During anesthesia	3 (2, 4)	3 (3, 4)	0.313
	After anesthesia	4 (3, 4)	4 (3, 4)	0.906
Second	FBRS
	Before anesthesia	4 (4, 4)	4 (3, 4)	0.121
	During anesthesia	4 (3, 4)	3 (3, 3.5)	0.063
	After anesthesia	4 (3.5, 4)	3 (3, 4)	0.105

FBRS, Frankl behavior rating scale

Discussion

Pain control holds paramount importance in dentistry. The fear associated with injection significantly affects the patient experience.¹⁷ Various methods were developed to alleviate pain during injection. The Buzzy Bee, an externally cold and vibrating device, was used in the current study to measure the child's discomfort during the injection of local anesthesia.

Pain reduction strategies include pharmacological, physical, and psychological interventions.^18,19 Consequently, approaches that are less time-consuming, simple to use, and inexpensive, especially while treating children, could offer clear advantages.¹⁹ One such device is the Buzzy Bee (MMJ Labs, Atlanta, Georgia, United States). The Bee's body vibrates while its detachable ice wings hold ice. It provides the advantage of both vibration and topical application of ice while giving local anesthesia.²⁰ Afferent pain transmission fibers (A delta and C fibers) are inhibited when vibration triggers nonnoxious A beta fibers, which may subsequently stimulate inhibitory interneurons. Cold administered for 30–60 seconds at the location of nociception may activate C nociceptors and block A delta fiber-mediated pain signals. By stimulating C fibers in response to cold, it is possible to transmit dull pain and harmful heat signals to the brain, which in turn activates systems for supraspinal modulation that raise the pain threshold generally and causes hypoalgesia anywhere the examination is performed.^21,22

Wong–Baker scale was used in this study to assess the pain experienced by the children. This scale is considered the most accepted subjective measure to report perceived pain, especially among children. As a self-reported scale, it easily allows children to identify and communicate their pain levels by selecting the face that best represents their experience.²³ Many previous studies have employed similar scale to assess the pain in children.^7,12,24,25 In this study, pain perceived by the children after using the Buzzy Bee device was lesser when compared to the other group of children who were administered LA without the application of the Buzzy Bee device. In contrast, studies by Suohu et al., Narimany et al., and Hassan et al. reported no difference in the pain perceived by the children who received Buzzy Bee application and conventional injection techniques.^17,23,26

A notable aspect of this study is the use of parental scale to ascertain the parent's perception of the child's ability to tolerate pain. Parents could perceive the feelings of the child and could inform regarding the child's fears about dental care.²⁷ Hence, they were considered a reliable proxy reporter to assess the pain experienced by the child. Parents were asked to rate their child's pain based on the behavior and expression in the present study. The median pain parental score was significantly lower for the Buzzy Bee group in the first visit. This was contradictory to the findings of AlHareky et al. that reported no difference in the parent's perception of the child's pain tolerance between the groups.¹¹ However, in the second visit, high pain tolerance by children was indicated by their parents in both the groups with no significant difference. The heightened sensitivity to their child's discomfort by the parent in the first visit could have attributed to the scores of the first visit. Meanwhile, the comfort and familiarity that the child expressed in the second visit could have been interpreted as reduced pain by the parents in the second visit.

The objective assessment of pain also included rating the SEM response in a video filmed during the procedure. In the first visit, the children treated with Buzzy Bee showed significantly lesser scores for eye and motor responses, implying the effectiveness of Buzzy Bee in reducing the perceived pain by children. In contrast to our study, AlHareky et al. reported no significant differences in the SEM scores. While in this study topical anesthetic gel was applied only in the control group prior to injection, AlHareky et al. applied topical anesthetic gel before LA administration in both the groups.¹¹ The effect of topical gel could have caused the variability of results from our study.

At the second visit in the present study, even when the objective scores were lesser while using Buzzy Bee, the difference between the groups was not statistically significant. This could be attributed to behavioral carryover effects underestimating the treatment effect, as they have fulfilled pain reduction.²⁸ Similar to the findings of the second visit in this study, the self-reported subjective score did not align with the behavioral scale measure of pain tolerance in the study by Abbasi et al.²⁹

Interestingly, the parental pain perception scores and SEM scores showed similar trends in their results in the present study. This might be due to the fact that both are observer–dependent scores and were based on visible behavior rather than the child's experience.

The results obtained in the present study reflected the pleasant experience and lesser pain perceived by the children when treated with Buzzy Bee. Both the subjective and objective scales used in the study reported reduced pain scores in the first visit. This suggests the effectiveness of Buzzy Bee in alleviating pain and discomfort during the initial exposure to dental procedures.

In addition to pain, the behavioral response and anxiety levels indicated by pulse rate were also assessed. On comparing the pulse rate of children before, during, and after administering infiltration we did not identify any difference between the groups at both the visits. Similar results of no difference in the pulse rate between the children treated with Buzzy Bee and conventional LA administration techniques were reported by Jain et al., as well as by Suohu et al.^9,17 However, Sahithi et al. and Shetty et al. reported that mean pulse rate was lesser among children treated with Buzzy Bee during the procedure compared to conventional techniques.^7,8 The results obtained in the present study implicates that, while Buzzy Bee could effectively reduce the subjective perception of pain, it might not be sufficient to elicit a measurable change in autonomic responses such as pulse rate. There are possibilities that the individual variability in baseline pulse rate and anticipation of treatment might have limited the sensitivity of pulse rate as a reliable pain indicator in this context. The behavior of the child assessed using FBRS did not show any difference between the groups in both the visits in the present study, which was in parallel with findings by Bilsin et al.²⁵

This study employed a split-mouth crossover design, in which each participant received intervention on one side, while the other served as a control, ensuring each participant served as their own control. Our study employed four reliable tools to assess the pain experienced by the child both objectively and subjectively. Administering both the treatment modalities in the same individual might have reduced the chance of occurrence of individual variability in our study. Influence of carryover effect in the present study was eliminated by the gap that was maintained after the first and second visit. As this study has incorporated the child, parent, and the investigator's perception of pain, we believe that a comprehensive result of the intervention has been obtained.

A potential limitation in the form of psychological bias could have affected the study, as the child's memory of the first visit could have influenced their behavior and experience. This might have influenced the perception and response during the second visit. This might have been the reason for difference in the results of subjective and objective assessment of pain, as the child could have underreported the pain based on familiarity rather than the actual sensory experience. Furthermore, all the procedures were performed by a single examiner, who was not blinded to pulse rates and objective and subjective pain scores of both the groups at each visit. Further studies employing validated anxiety assessment tools on larger stratified samples based on age and previous dental experience and children showing different levels of cooperation may provide deeper insights about this. Within the limits of the study, we conclude that the Buzzy Bee device was found to be an effective tool in reducing the pain perceived during local anesthesia administration in cooperative children, particularly during the initial visits.

Conclusion

The externally cold and vibrating Buzzy Bee apparently reduced the pain perception and increased the tolerance to withstand pain of intraoral LA administration in children. An overview of pain responses has been obtained from a comprehensive rating of the participant undergoing the procedure, the accompanying parent, and the principal investigator in this crossover study. Significant reductions in subjective pain perception scores were observed at both visits; however, the observed scores did not change at the second visit. Moreover, children's behavior did not alter at the second visit, which can be explained by the fact that they had become accustomed to the surroundings and procedure.

Orcid

Satish Vishwanathaiah https://orcid.org/0000-0002-8376-297X

Prabhadevi C Maganur https://orcid.org/0000-0002-0959-2597

Varsha Manoharan https://orcid.org/0000-0002-8409-5996