Effect of photobiomodulation on recovery from oral soft tissue local anaesthesia in paediatric patients: a preliminary split-mouth randomized clinical trial

Paediatric dental patients are particularly vulnerable to inadvertent soft-tissue injury following local anaesthesia (LA) This preliminary study evaluated. the clinical efficacy of 810-nm diode laser photobiomodulation (PBM) in reversing oral soft-tissue anaesthesia in paediatric patients. Thirty-four children aged 8-12 years requiring bilateral primary toothextractions under infiltration LA were enrolled in by consideration of ethical codes. Local anaesthesia was administered using 2% lidocaine with 1:80,000 epinephrine, as per the local infiltration anesthesia protocol. Participants were randomly allocated to receive both PBM and sham Laser with 7-10 days washout period between the two interventions. PBM was delivered using an 810-nm diode laser in continuous mode at 200 mW for 12 s per point at six predefined intraoral and extraoral sites. An independent examiner assessed soft-tissue sensation at 5-minute intervals by standardized bilateral palpation, using the non-anaesthetized side as the reference. The primary outcome was time to first assessment at which sensation on the anaesthetized side was judged normal. Data were analysed using a paired-samples t-test. Mean reflection time was significantly shorter in the PBM group (60.7 ± 27.3 min; p < 0.001) compared with the Sham lasergroup (78.2 ± 17.0 min). Subgroup analysis demonstrated significant reductions in reflection time in both maxillary and mandibular arches. Photobiomodulation using an 810-nm diode laser demonstrated a reduction in subjective soft tissue anaesthesia recovery time following infiltration LA in paediatric dental patients under the conditions tested.