Renal dysplasia with secondary hyperparathyroidism and loose teeth in a young dog.

In a dog with renal dysplasia and secondary hyperparathyroidism, loose teeth resulted from excessive resorption of alveolar bone. Sharpey's fibers, still anchored in the cementum, were lost in the replacing fibrous tissue and few fibers found their way to distant bone fragments. The alveolar bone is the site of predilection for the excessive, generalized resorption of bone in hyperparathyroidism. Clinical radiographic examination of the jaws is a valuable tool in the detection of the disease.