Ca. Hedin et al., THE RETROCUSPID PAPILLA AND FACTOR XIIIA - AN EPIDEMIOLOGIC AND HISTOMORPHOLOGIC STUDY, Scandinavian Journal of Dental Research, 102(5), 1994, pp. 290-294
The retrocuspid papilla (RCP) is a poorly recognized entity. In one pa
rt of our study, we found 10 cases of lesions clinically compatible wi
th RCP in 1150 consecutively examined patients. In another part of the
study, we found 15 cases of RCP in more than 2000 consecutive cases o
f oral mucosal hyperplasia submitted as surgical biopsies during 1989-
92. The lesions were situated in the attached gingiva, lingual to the
two mandibular canines, often bilaterally. They were covered by normal
pink mucosa with a size and a height each of 2-3 mm. Histologically,
the RCP was a broad-based, often downfolded hyperplasia, covered with
a parakeratinized epithelium of normal thickness. The rete pegs were o
ften elongated and blunt, frequently bent inward toward the center. Th
e lamina propria was mostly composed of a loosely arranged, delicate,
fibrous connective tissue. The lesions could be classified into two gr
oups by the presence or absence of stellate and occasionally multinucl
eated fibroblasts. Immunohistochemical staining with an FXIIIa antibod
y disclosed a population of reactive spindle-shaped cells, mainly loca
lized in the connective-tissue papillae. These cells may be of pathoge
netic importance.