Overview
Preoperative anxiety and loud equipment noises, such as dental drills, create significant stress and autonomic fluctuations in patients undergoing oral surgery. Brainwave entrainment using alpha-band (10 Hz) binaural beats is a non-invasive audio method designed to promote relaxation and activate the parasympathetic nervous system. The purpose of this randomized controlled clinical trial is to evaluate the clinical effectiveness of a 10 Hz alpha-band binaural beat track embedded in continuous rain sound on reducing perioperative anxiety, maintaining hemodynamic stability, and improving postoperative recovery in patients undergoing impacted third molar extraction. Fifty-four healthy adult participants (ASA I) scheduled for impacted third molar surgery will be randomly assigned into three groups:Binaural Beats Group: Listening to 10 Hz alpha binaural beats embedded in a rain sound via active noise-cancelling (ANC) headphones during surgery. Placebo Group: Listening to rain sound only via ANC headphones during surgery. Active Control Group: Wearing ANC headphones with no audio broadcast (noise cancellation feature only). Preoperative dental anxiety, hemodynamic parameters (blood pressure, heart rate, oxygen saturation) at four distinct intraoperative stages, post-surgical stress levels, and 7-day postoperative pain/analgesic consumption will be measured and compared among the groups.
Description
Dental anxiety and phobia are common psychological challenges that frequently lead to treatment avoidance, increased stress, and heightened pain perception during surgical procedures. High-frequency acoustic triggers generated by dental handpieces further exacerbate acute intraoperative stress and autonomic reactivity. While pharmacological management options exist, non-pharmacological neuromodulatory interventions provide safe and non-invasive alternatives with minimal side effects. Binaural beats occur when two slightly different auditory frequencies are presented separately to each ear, causing the brainstem's superior olivary complex to perceive a third oscillating frequency. Alpha-band frequencies (8-13 Hz) are associated with reduced state anxiety and enhanced parasympathetic tone. Integrating a 10 Hz binaural beat into continuous broadband masking noise (rain sound) aims to deliver therapeutic neuromodulation while simultaneously masking high-frequency clinical sounds. Study Protocol and Workflow:Preoperative Evaluation: Eligible participants complete the Modified Dental Anxiety Scale (MDAS) questionnaire in the waiting room prior to surgery. Randomization \& Blinding: Participants are randomized into three equal groups (n=30 per group) using sealed envelopes. Outcome assessors and statisticians are blinded to group allocation. Surgical Standardization: All surgical extractions are performed by a single experienced oral and maxillofacial surgeon following standardized surgical protocols (local anesthesia, mucoperiosteal flap elevation, bone drilling/tooth sectioning under saline irrigation, and primary suturing). Hemodynamic Monitoring: Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and oxygen saturation (SpO2) are recorded at four physiological stress milestones:T0: Baseline resting state in the dental chair. T1: Moment of local anesthesia administration. T2: Maximum stress period during bone drilling and tooth sectioning. T3: Recovery phase following final suture placement. Postoperative Assessment: Immediately after surgery, perceived stress and discomfort are measured using a 10-point Visual Analogue Scale (VAS). Patients are provided with a 7-day pain diary to record daily maximum pain scores (VAS 0-10) and total analgesic tablet consumption.
Eligibility
Inclusion Criteria:
- Systemically healthy patients classified as American Society of Anesthesiologists (ASA) physical status I
- Aged between 18 and 45 years
- Requiring surgical extraction of at least one impacted mandibular third molar
- Normal hearing acuity in both ears
- Voluntary participation and signed written informed consent
Exclusion Criteria:
- Presence of any systemic disease (ASA II or higher)
- History of hearing impairment, acoustic trauma, or tinnitus
- History of neurological disorders, epilepsy, or psychiatric conditions
- Current use of psychotropic, sedative, or analgesic medications within 48 hours prior to surgery
- Pregnancy or lactation
- Known allergy to local anesthetics or prescribed medications
- Active acute pericoronitis or severe localized infection at the surgical site


