El-Labban N G, Kramer I R
Oral Surg Oral Med Oral Pathol. 1981 May;51(5):509-15. doi: 10.1016/0030-4220(81)90011-6.
The hyaline rings found in chronic periostitis and a radicular cyst were investigated ultrastructurally. These rings were composed of fine fibrillar material which was probably derived from degraded collagen fibrils, all of which eventually became degraded and unrecognizable. Foreign-body material in the form of circular bodies of probable plant origin were also found and should not be confused with the hyaline rings.
