OSTEOPETROSIS: Roentgenographic features:Medullary cavities are replaced by bone and the cortex is thickened. Density of bone may be such that, the roots of the teeth are nearly invisible on dental roentgenogram. Ends of long bones are bulbous called Erlenmeyer's flask deformity. In osteopetrosis, there is normal appositional bone growth, but failure of physiologic root resorption.On X-ray, bones might appear club-like or show an appearance of a bone within bone (Endobone). Vertebrae are extremely radiodense and may show alternating bands, known as the "rugger-jersey" sign. Lab findings of Osteopetrosis:Myelophthisic anemia (as bone marrow is replaced by bone). Hypocalcemia (Shafer reports normal serum calcium, phosphorus and alkaline phosphatase levels). Secondary hyperparathyroidism.