Development and Validation of an Extraoral Condyle Locating Device and Its Effect on Low-Level Laser Therapy in Patients With Skeletal Class II Malocclusion: Protocol for a 2-Phase Randomized Controlled Trial

Background Precise localization of the mandibular condyle is essential for extraoral therapeutic procedures such as low-level laser therapy (LLLT) in patients with skeletal class II malocclusion undergoing myofunctional appliance therapy. Conventional localization methods rely on palpation and visual estimation, which are operator dependent and may compromise reproducibility and treatment outcomes. To address this limitation, a spectacle-mounted extraoral condyle locating device (EOCLD) has been developed to facilitate accurate and consistent condylar targeting. Objective This study aims to develop and validate the EOCLD for precise condylar localization and evaluate its impact on the clinical efficacy of LLLT in patients with skeletal class II malocclusion undergoing myofunctional appliance therapy. Methods This 2-phase study will be conducted in patients aged 10 to 13 years in a growth phase with skeletal class II malocclusion. In phase 1, the EOCLD will be evaluated for accuracy and reproducibility using standardized lateral cephalometric imaging. In phase 2, a prospective randomized controlled trial will be conducted in which participants undergoing myofunctional appliance therapy will be randomly allocated to either EOCLD-guided LLLT or conventional unguided LLLT. Skeletal and dentoalveolar changes will be assessed using standardized cephalometric analyses, while condylar growth and mandibular changes will be evaluated using pretreatment and posttreatment cone beam computed tomography (CBCT) imaging. Treatment duration, patient-reported comfort, and compliance will also be assessed. Results The study is self-funded and received approval from the institutional ethics committee on November 28, 2025. Phase 1 data collection took place from May 21 to August 30, 2026, with EOCLD validation performed in 50 participants. As of September 2026, the data are undergoing statistical analysis. Phase 2 is scheduled to commence on December 1, 2026. Conclusions This study will establish the clinical validity of the EOCLD and determine whether guided LLLT enhances treatment efficiency and skeletal outcomes in skeletal class II therapy. Trial Registration Clinical Trials Registry–India CTRI/2026/02/102982; https://tinyurl.com/4t3bwrnz International Registered Report Identifier (IRRID) PRR1-10.2196/94481