Hyperactivity of the lateral pterygoid muscle (LPM) is one of the theories postulated to explain anterior disc displacement, which can result in difficulty in jaw opening, jaw protrusion, or jaw-deviation dystonias and interferes with mastication, speech, and swallowing. Injection of botulinum toxin of the LPM is considered a conservative therapeutic modality for this condition.

The LPM is a deep facial structure and several techniques have been described that use magnetic resonance imaging, arthroscopic, or electromyographic guidance to perform intramuscular botulinum toxin injection safely this to prevent incorrect injection or complications, such arterial bleeding. This study provided a described step-by-step description of the computer-aided design and manufacturing procedure for the fabrication of an in-house guide to simplify the method of botulinum toxin injection in the LPM and ensure accuracy and safety in medical office.