Along with sanitation improvements and the discovery of antibiotics, vaccines had the largest impact on infectious diseases in the 20th century.

Which of these mandibular teeth generally have the longest roots?

a. Central incisors b. Lateral incisors c. Canines d. Premolars

If a lateral lumbar spine reveals the L5-S1 joint space to be open, what must be applied in order to successfully image the L5-S1 intervertebral space open?

angle the central ray 5 degrees caudal angle the central ray 10 degrees caudal angle the central ray 5 degrees cephalic use a perpendicular central ray