Original Article 1, Issue 13.3

Effect of Hypnopedia on Dental Anxiety, Cooperation, and Orofacial Behavior in Children With and Without Risk of Sleep-Disordered Breathing: A Randomized Controlled Study

ABSTRACT

Background:

Childhood sleep-disordered breathing (SDB) is linked with behavioral dysregulation, dental anxiety, and orofacial dysfunction, making pediatric dental care more complicated. Hypnopedia, or sleep-learning via auditory suggestion during non-rapid eye movement sleep, has shown promise in behavioral modulation but has never been tested in pediatric dental situations.

Objectives:

To assess the effectiveness of hypnopedia in minimizing dental fear, enhancing cooperation, and maximizing orofacial posture in children, with a comparison across children at high and low risk for SDB.

Methods:

A prospective, randomized, controlled, single-blinded, 2×2 factorial design trial was completed on 160 children aged 5 to 8 years who needed at least two dental visits. Participants were stratified based on high- or low-risk SDB status using the Sleep Disturbance Scale for Children (SDSC) or FAirEST-15, and randomly assigned to either hypnopedia intervention (positive self-statements during early non-rapid eye movement sleep) or control (white noise). Main outcomes were change in dental anxiety (Children's Fear Survey Schedule – Dental Subscale [CFSS-DS]) and cooperation (Frankl Behavior Rating). Secondary outcomes were orofacial rest posture, parent-reported changes in behavior, and intervention compliance.

Results:

The CFSS-DS and Frankl score were improved in the hypnopedia groups compared with control groups (P < 0.05), especially in the high-SDB-risk subgroup. Orofacial rest posture and parental concern about behavior also improved after intervention. Two-way analysis of variance revealed positive interaction between hypnopedia exposure and SDB risk status.

Conclusions:

Hypnopedia is a promising, noninvasive adjunct for enhancing behavioral cooperation, decreasing dental fear, and facilitating orofacial development in pediatric dental patients. Pediatric dental patients with SDB risk appear especially amenable, implicating a role for sleep-based behavioral modulation in pediatric dentistry.

Keywords:

hypnopedia, pediatric dentistry, sleep-disordered breathing, dental fear, behavior management, orofacial posture.

Citation:

Nair LS, Salim S. Effect of Hypnopedia on Dental Anxiety, Cooperation, and Orofacial Behavior in Children With and Without Risk of Sleep-Disordered Breathing: A Randomized Controlled Study. J Dent Sleep Med. 2026;13(3).

INTRODUCTION 

Sleep-disordered breathing (SDB) in children is a continuum of disorders ranging from primary snoring to obstructive sleep apnea (OSA) with an incidence varying between 1% and 11%.¹ SDB has been implicated with numerous adverse outcomes such as neurobehavioral dysfunction, mood changes, and academic impairment.^2,3 Specifically, daytime symptoms such as hyperactivity, irritability, and impulse control difficulties make pediatric dental behavioral management challenging.

Dental anxiety is one of the most prevalent behavioral problems presented in pediatric dentistry. Children with intrinsic behavioral dysregulation, frequently associated with sleep disturbances, are less resilient to dental interventions.⁴ Also, mouth breathing, low posture of the tongue, and abnormal orofacial muscle tone are frequent in children with SDB and may cause interference with both orofacial craniofacial development and behavior during dental treatment.^5,6

Hypnopedia or sleep-learning is the presentation of audio-suggestive stimuli during sleep—specifically during non-rapid eye movement (NREM) stages when the brain is most receptive to procedural and behavioral reinforcement.⁷ Although not widely explored in pediatric dentistry, hypnopedia has proved promising for habit reinforcement and behavioral modulation in other areas of pediatric treatment, such as language learning and habit reversal.^8,9

Despite this promise, there are no studies that have assessed the effect of hypnopedia on influencing behavior, anxiety, or orofacial rest postures in pediatric dental patients, especially those who are at risk of SDB. With the mutual relationship between sleep and behavior, the current study investigates whether an out-of-office, noninvasive sleep-learning intervention will affect dental treatment behavior in children with disparate sleep quality.

This research seeks to establish whether the provision of positive, targeted audio cues on sleep can decrease dental fear, enhance cooperation, and improve orofacial rest posture in children. It also investigates whether these outcomes vary according to the child's risk profile for SDB. By uniting the fields of sleep science and pediatric behavior management, the goal of this research is to lead to implementation of an innovative, low-cost adjunct to enhance outcomes in pediatric dentistry.
 

OBJECTIVES

Primary Objectives

1. To assess the effectiveness of hypnopedia to alleviate dental anxiety in children receiving routine dental care.
2. To determine whether the application of hypnopedia improves behavioral cooperation during clinic visits, as indicated by standardized pediatric behavior rating scales.
3. To compare the efficacy of hypnopedia for children who are identified as low risk and high risk for SDB, thus determining the modifying influence of sleep quality on behavioral effects.
    

Secondary Objectives

1. To measure parental perception of changes in behavior and orofacial function after the hypnopedia intervention, via standardized feedback measures.
2. To monitor and record alterations in orofacial rest posture—i.e., tongue position, lip seal, and nasal breathing—after completion of the intervention period, correlated with clinical findings.
3. To test the feasibility, acceptability, and compliance with an at-home hypnopedia program delivered over a 2-week period, according to caregiver compliance diaries and qualitative acceptability ratings.

These goals seek to establish a multidimensional assessment of hypnopedia not just as a behavior instrument but also as a possible adjuvant in orofacial and sleep-integrated pediatric dentistry.
 

ETHICAL CONSIDERATIONS

This study protocol was considered and approved by the Institutional Ethical Committee (IEC) of the study center, reference number IEC Number: PMS/IEC/2024/Add/dhr/June/45/Rev-1, which also already performed a similar observational study on pediatric sleep-disordered breathing performed in the same setting. All human studies were carried out according to the ethical rules of the institutional and/or national research committee and with the 1964 Helsinki Declaration and later amendments.

Informed consent in writing was provided by parents or legal guardians before participation in the study. Whenever possible, verbal or written assent from the participating children was also acquired. The intervention held no anticipated physical or psychological risks for participants because the hypnopedia procedure consisted of passive exposure via audio to sleep, a noninvasive and behaviorally neutral procedure.

All information was anonymized by participant identification codes, and confidentiality of health data was strictly upheld. Participation was voluntary, and families were assured that they were free to withdraw at any time with no effect on the child's clinical care.
 

STUDY DESIGN AND METHODOLOGY

Study Design

Prospective, randomized, controlled, single-blinded, 2×2 factorial clinical trial over 4 weeks of study duration. Factorial design enabled simultaneous assessment of the effect of the intervention (hypnopedia versus control) and the effect of the child's risk status for sleep-disordered breathing (low versus high).
 

Study Duration

Participants were tracked for 4 weeks. Baseline assessment and screening occurred during the first week. The next two weeks consisted of intervention, where each night, either the hypnopedia or control audio tracks were played at home. Postintervention behavior and orofacial reassessments were done during the fourth week.
 

Setting

The research was done in the pediatric dental clinic of a tertiary dental college, and prior approval was gained from the Institutional Ethics Committee. Informed consent was obtained from parents or guardians, and assent from children where appropriate.
 

Randomization and Group Allocation

 Children were stratified according to their risk for SDB with use of validated screening instruments. Within SDB risk category, participants were randomly assigned to intervention or control groups with a computer-generated randomization sequence. Allocation concealment was ensured with use of sequentially numbered opaque sealed envelopes.

The four study groups were:

• Group A1: Hypnopedia intervention + Low SDB Risk
• Group A2: Hypnopedia intervention + High SDB Risk
• Group B1: Control group (white noise) + Low SDB Risk
• Group B2: Control group (white noise) + High SDB Risk

Each group comprised an equal number of participants (n = 40 per group), ensuring balanced sample sizes for comparative analysis. The dental examiners assessing behavioral outcomes and orofacial features were blinded to group allocation. Participants and their caregivers were not blinded due to the nature of the intervention. This design permitted evaluation of both the independent and interactive effects of hypnopedia and sleep quality on pediatric dental behavior, thereby enhancing the internal validity of the findings.

STUDY POPULATION

Inclusion Criteria

1. Children between 5 and 8 years of age.
2. Medically fit children who needed at least two scheduled visits for dental procedures such as pulpotomy, restorations, or other similar interventions.
3. Children with mild to moderate dental anxiety, defined as a score on the Children's Fear Survey Schedule–Dental Subscale (CFSS-DS) higher than 19.
4. Informed written consent from parents or legal guardians, and verbal or written assent from the children according to their age.

 Exclusion Criteria

1. Children who have a past history of neurologic, developmental, or severe behavioral disorders (e.g., Autism Spectrum Disorders, Attention Deficit Hyperactivity Disorder that required pharmacologic treatment).
2. Previously diagnosed sleep disorders or concurrent use of sedative drugs.
3. Children with hearing loss or clinically significant language delays likely to compromise auditory reception or verbal cue comprehension.

Sample Size Calculation: An a priori power analysis was also performed using G*Power software (version 3.1.9.2). With an anticipated medium effect size (Cohen d = 0.6) for behavioral outcomes, 80% power, and a significance level (alpha) of 0.05, the required sample size was calculated as 40 children per group. For four groups in the 2×2 factorial design, the total sample size was 160 participants.

TOOLS AND INSTRUMENTS

Dental Anxiety

Dental anxiety was measured by the CFSS-DS. This established questionnaire contains 15 items rated on a 5-point Likert scale with the total score ranging from 15 to 75 points. A higher score shows more dental fear. It was used at baseline (preintervention) and postintervention to measure change.

Behavioral Cooperation

SDB Risk Stratification

Orofacial Observation

Parental Perception

1. Likert-scale items (1 to 5) assessing perceived changes in sleep, cooperation, and dental anxiety.
2. Open-ended questions for qualitative understanding of child behavior and parental experience with the intervention.

Audio Compliance

INTERVENTION

The group that was receiving hypnopedia was given a prerecording in the form of a soothing, kid-friendly voice reading positive behavioral statements intended to encourage cooperation and adequate orofacial posture. The recording said statements such as, "You are brave and relaxed at the dentist. You open your mouth like a superhero. You breathe through your nose. Your lips remain together. You put your tongue up and loose." This recording was repeated every evening during the first 2 hours of the child's sleepiness—non-REM sleep—when the mind is most open to external auditory stimulation. Each treatment took approximately 5 to 7 minutes and was given for 10 successive evenings.

Control participants were instead given an audio recording of neutral, low-level white noise without semantic or linguistic content. The same duration and frequency was played as that of the hypnopedia audio. Both sets of participants completed the protocol at home, and parents were given instructions on how to prepare for best playback conditions (eg, placement of the source of the audio, minimizing external interference).

This design allowed the study to assess the particular behavior and physiologic effects due to content-based sleep audio listening exposure (hypnopedia) while holding constant nonspecific auditory stimulation.

The 4-week total study duration was selected to balance two needs: to allow adequate time for measurable behavioral and orofacial changes to emerge after the intervention, and to minimize participant attrition typical of longer home-based pediatric trials. The 10-day intervention window corresponds to established behavioral-conditioning literature suggesting that nightly repetition for 7 to 10 days optimizes consolidation of new cues without habituation. The 5- to 7-minute playback time was based on pilot trials showing that longer recordings tended to disturb sleep onset, whereas shorter exposures reduced message reinforcement.

OUTCOME VARIABLES

 The research employed primary as well as secondary outcome measures in order to thoroughly assess the effect of hypnopedia. The primary outcomes were the difference between CFSS-DS scores at baseline and postintervention, reflecting the efficacy of hypnopedia in eliminating dental anxiety, and the difference in Frankl Behavior Rating between the first and second dental visits, reflecting behavioral improvement during treatment.

Secondary outcomes measured more general behavioral and physiologic effects. These were clinical changes in orofacial rest posture—such as tongue position, lip seal, and nasal breathing—improving as a measure of unconscious behavioral reinforcement. Parent-reported behavior improvement and reduced anxiety levels were also gathered using standardized questionnaires, adding a qualitative edge to results. SDB risk status versus responsiveness to the intervention was correlated to investigate whether sleep quality can modulate the behavioral effects of hypnopedia.

DATA ANALYSIS

All statistical analyses were performed using SPSS. Paired t-tests with normally distributed data or Wilcoxon signed-rank test with nonparametric distributions were used to compare within-group preintervention and postintervention values (changes in CFSS-DS scores, Frankl Behavior Ratings). Comparisons between groups (hypnopedia versus control, low versus high SDB risk) were made using independent t-tests or the Mann–Whitney U test based on normality assumptions. In order to examine interaction effects of intervention type by SDB risk category, a two-way analysis of variance was used. This enabled the examination of both main effects as well as possible synergistic or moderating effects of SDB status on intervention outcomes. In addition, multiple linear regression models were run to control for possible confounders such as age, sex, and mean nightly sleep time. Significance was established at P < 0.05 for all tests.

RESULTS

Table 1 presents the 2×2 factorial grouping of children based on two criteria: whether they received the hypnopedia intervention or not; whether they were at low or high risk for SDB, as determined by SDSC scores. Each group had 40 participants, for a total of 160. This ensures equal distribution across intervention and SDB risk strata.

Table 2 shows the CFSS-DS measuring dental anxiety. Group A1 (hypnopedia + low SDB risk) showed the greatest reduction in anxiety. Group A2 also improved, though less than A1, indicating that SDB may blunt the effect of hypnopedia. Groups B1 and B2 (controls) showed minimal or no statistically significant improvement. 

Table 3 shows Frankl ratings range from 1 (definitely negative behavior) to 4 (definitely positive behavior). Significant behavioral improvement was observed in the hypnopedia groups (A1 and A2). Group A1 showed the most improvement. Control groups had marginal, statistically non-significant changes. This confirms hypnopedia’s role in behavioral conditioning during dental procedures.

Table 4 shows the percentages of children who showed improvement in oral rest posture parameters. Group A1 again shows the highest gains in nasal breathing, lip seal, and tongue posture. This suggests that sleep-based cues might reinforce myofunctional habits. Children with high SDB risk (A2) improved less—possibly due to disrupted or lower-quality sleep affecting learning consolidation. Control groups showed minimal gains.

Table 5 shows that the parents of children in hypnopedia groups reported greater perceived improvements. Scores reflect strong agreement (score ≥ 4) in A1 and A2, particularly for behavior and cooperation. Even sleep quality was perceived to improve in hypnopedia groups, possibly due to calming presleep rituals. Control groups reported lower, near-neutral scores.

Table 6 indicates that the main effects include both the intervention (hypnopedia) and SDB risk status independently influenced outcomes. Interaction effect indicates that the effectiveness of hypnopedia was modified by SDB status—i.e., that is, hypnopedia worked better in children without SDB. Statistically significant interaction (P < 0.05) confirms that intervention outcomes are not uniform across SDB risk groups.

As shown in Table 7, the most prominent differences between high- and low-SDB-risk groups were observed for mouth breathing during sleep, frequent snoring, and night awakenings, which were markedly more prevalent among children in the high-risk group (P < 0.001). Daytime sleepiness and difficulty waking in the morning were also significantly higher in the high-risk category. These findings highlight the baseline functional airway disparities between the two groups, which may partly explain the greater responsiveness to hypnopedia observed in the low-risk subgroup.
 

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DISCUSSION

The current randomized controlled trial examined the effectiveness of hypnopedia—a sleep-based, noninvasive behavioral intervention—on pediatric dental anxiety, cooperation, and orofacial behavior, with further analysis according to the child's risk for SDB. The findings show that hypnopedia was effective in significantly enhancing outcomes in all major areas, with the strongest effects in children at low risk for SDB.

Dental Anxiety

The CFSS-DS scores indicated a considerable decrease in both the hypnopedia groups, particularly in children at low SDB risk (A1). This is congruent witha previous study that  indicated significant dental anxiety reductions with nonpharmacologic interventions in children.⁴ In the same way, Girón et al. illustrated that hypnotic induction procedures can successfully reduce dental anxiety among children.¹⁰ The study findings validate hypnopedia as an instance of passive behavioral conditioning, especially efficient in children without disturbed sleep patterns.

Cooperation and Frankl Behavior Rating

Children in the hypnopedia groups exhibited meaningful behavioral enhancements during dental appointments. Previous studies also reported comparable changes in cooperation with conventional behavioral management methods such as tell-show-do and voice control.¹¹ Additionally, Kulkami et al.  identified that sleep quality can significantly affect children's responsivity to dental behavior management.¹² This work is extended by the current study findings that interventions based on sleep phase such as hypnopedia are more likely to succeed when sleep quality is intact, such as in children at low risk for SDB.

Orofacial Rest Posture

In the current study, significant improvements were observed in lip sealing, nasal breathing, and tongue posture among children receiving hypnopedia. This is in agreement with a previous study, that identified that orofacial myofunctional therapy enhanced equivalent parameters among children with nasal obstruction.⁶ These outcomes likely reflect enhanced neuromuscular coordination and reinforcement of oral functional patterns through subconscious auditory conditioning during sleep. Nevertheless, the magnitude of change was modest and varied depending on baseline airway patency. Thus, hypnopedia may be regarded as a supportive behavioral aid rather than a definitive treatment modality, complementing orthodontic, myofunctional, and ear, nose, and throat--based therapies in comprehensive airway rehabilitation.

Parental Perceptions

The parent-assessed outcomes corresponded well with the clinical ratings. Cox IC et al. highlighted the validity of parental response in pediatric dental assessment, especially for behavior and cooperation.¹³ The current study’s A1 and A2 high Likert scores highlight the real-world effect of hypnopedia as seen in the home and clinical environments.

Interaction With SDB Risk

Statistical interaction tests revealed that children at high risk for SDB were less responsive to hypnopedia, especially in cooperation and anxiety measures. This aligns with Chervin et al., who linked SDB with impaired executive function and emotion regulation in children.³ Galland et al.  also verified this association in their meta-analysis of SDB and cognitive and behavioral difficulties.¹⁴ Children at low risk for SDB typically have more stable sleep architecture, better oxygen saturation, and fewer arousals, which collectively enhance the consolidation of subconscious auditory learning during NREM sleep. This relative physiological stability likely facilitates stronger conditioning effects from hypnopedia, allowing reinforcement of desired oral posture patterns such as lip seal, nasal breathing, and proper tongue rest position. Additionally, better neuromuscular coordination and unobstructed airway function in these children contribute to greater adaptability to behavioral training cues.

In contrast, children at high risk for  SDB often experience disrupted sleep cycles due to intermittent hypoxia, microarousals, and heightened sympathetic activity. These factors may impair memory consolidation during sleep and reduce the brain’s ability to integrate externally presented cues. Moreover, chronic mouth breathing and orofacial muscular hypotonia may limit their capacity to internalize and maintain functional changes, despite exposure to hypnopedic suggestions. From a behavioral standpoint, children at high risk for SDB also tend to show reduced attention span and cooperation during dental procedures, possibly due to cumulative sleep deprivation and discomfort related to airway compromise. Such factors further attenuate their responsiveness to hypnopedia-based conditioning
 

Critical Implications

 
The study findings propose that hypnopedia can be incorporated into practice as a home preparatory approach, particularly for children without SDB. Yet, the diminished efficacy in children with SDB emphasizes the necessity of initial sleep screening. The combination of hypnopedia and active treatments, such as myofunctional training or cognitive behavior techniques, should be examined in subsequent trials.
 

Limitations and Future Directions

This research did not track sleep structure (NREM sleep stages), which constrains assessment of best timing for delivery of hypnopedia. Parents were instructed to begin playback only after confirming stable, rhythmic breathing and absence of movement—indicators of sleep onset. Each morning, children were informally asked whether they recalled hearing the audio; none reported recall. Although objective verification of NREM sleep (polysomnography) was beyond the study’s scope, playback was scheduled within the first two hours of sleep, when NREM stages N2–N3 predominate. Objective measures such as actigraphy or polysomnography would enhance accuracy. More extended follow-up is also required to assess retention of behavioral modification and possible incorporation into orthodontic or airway-directed therapy. Also, because the caregivers were aware of their child’s group assignment, their perception of behavioral change may have been influenced by positive bias; future studies should incorporate blinded outcome assessments.
 

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SUBMISSION & CORRESPONDENCE INFORMATION

Submitted July 11, 2025
Submitted in final revised form October 13, 2025
Accepted for publication October 23, 2025

Address correspondence to: Dr. Lekshmy SR Nair, MDS. Email: lekshmysrnair@gmail.com
 

DISCLOSURE STATEMENT

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