Summary A study was conducted in dentulous and edentulous subjects to determine the location of occlusal plane as related to the maxillomandibular space. The results from both the dentulous and edentulous groups indicate a close angular affinity between the occlusal and maxillary planes. In the dentulous group, significant associations were found between the angulation of the occlusal plane to the maxillary plane and the height and length of the maxillomandibular space. The occlusal plane in the long-and-low type of maxillomandibular space tends to be more parallel to the maxillary plane, while the occlusal plane in the short-and-high types of maxillomandibular space tends to be more steeply angulated to the maxillary plane. The occlusal plane deviates away from a mean angulation to the maxillary plane when the height and length of the maxillomandibular space tend to be toward the opposite extremes of the normal range.