Angulation of bone in lower molar area is about:
In the posterior mandible, the submandibular fossa mandates implant placement with increasing angulation as it progresses distally. Hence in the second premolar region, the angulation may be 10 degrees to a horizontal plane; in the first molar area, 15 degrees; and in the second molar region, 20 to 25 degrees.
5 degrees
10 degrees
15 degrees
20 degrees