Fig. 2.

The determination of Point E1 and E2. (A) The lowest point (Point M) of the maxillary alveolar ridge intersects with a perpendicular line extending from the lateral margin of the nasal incisure. The lowermost point (Point N) of the alveolar crest was identified by taking a line at a tangent to the lateral margin of the infraorbital foramen; (B) Point E1 is located 5 mm palatally from Point M, and point E2 is situated 5 mm palatally from Point N