The primary objective of this cadaver study was to assess the feasibility of a novel custom helical distraction system and a patient-specific antral maxillary distractor. The study involved two fresh cadaver heads and followed a systematic procedure. First, virtual planning was conducted for an asymmetric maxillomandibular advancement. Custom patient-specific hardware was then fabricated to enable sequential mandibular advancement and gradual maxillary distraction. The mandibular lengthening procedures were found to be highly accurate, with only minor deviations from the planned results. In terms of maxillary distraction, the patient-specific antral distractors demonstrated favorable outcomes, with two noteworthy exceptions. Ideal forward maxillary advancement was short by a modest 2-3 mm in both cadavers. Additionally, cadaver 2 exhibited an unplanned pitch malrotation. However, an excellent occlusion was achieved in cadaver 1 and an acceptable anterior occlusion in cadaver 2, albeit with bilateral posterior open bites that could be readily corrected with interdental elastics in a clinical setting. This cadaver model study provides compelling evidence for the feasibility of patient-specific antral helical distractors, highlighting their potential to yield positive outcomes. Importantly, the study results suggest that patient-specific antral distractors may offer superior results compared to the current standard of linear distractors.