Which one of the following features is NOT associated with 1° hyperparathyroidism?

Radiographic features of hyperparathyroidism: The radiographic findings in this disease are of particular importance. The bones of affected persons show a general radiolucency as compared with those of normal people. Later, sharply defined round or oval radiolucent areas develop, which may be lobulated. If such a lobulated lesion develops in the mandible, it must be carefully differentiated from ameloblastoma, which frequently has the same appearance. Small cystic areas may be seen in the calvarium, and large and/or small sharply defined radiolucencies may be present in the maxilla and/or mandible. These small cystic areas must be differentiated from the lesions of multiple myeloma and eosinophilic granuloma. In this jaws, the bone radiograph in hyperparathyroidism has been described as having a 'ground-glass' appearance. The lamina dura around the teeth may be partially lost. Hypercementosis is not seen in primary hyperparathyroidism.