International Journal of Clinical Case Reports, 2016, Vol.6, No.15, 1-9
6
Figure 6 a Histo-pathological examination revealing proliferating hyperkeratinized epithelium and connective tissue showing
collagen fibers and proliferating fibroblasts
Figure 6 b Histo-pathological examination showing trabeculae of woven bone with collagen fibers and proliferating fibroblasts
3 Discussion
Gingiva is one of those anatomical regions in the oral cavity with the broadest array of lesions occurring ranging
from inflammatory to neoplastic. POF is one such reactive lesion, which occurs exclusively on gingiva. Although,
intra-oral ossifying fibromas have been described in the literature since the late 1940s, still there are lot of theories
and various schools of thoughts regarding its pathogenesis. The widely accepted etio-pathogenesis for POF is the
inflammatory hyperplasia of the cells of the periosteum or periodontal ligament; as there is excessive proliferation
of mature fibrous connective tissue in response to gingival injury, gingival irritation, sub-gingival calculus or a
foreign body in the gingival sulcus. Chronic irritation of the periosteal and periodontal membrane causes
metaplasia of the connective tissue and resultant initiation of formation of bone or dystrophic calcification. An
origin from cells of periodontal ligament has been suggested because of exclusive occurrence of POF from
interdental papilla, the proximity of gingiva to periodontal ligament, the presence of oxytalan fibres within the
mineralized matrix of some lesions, the age distribution which is inversely related to the number of lost permanent
teeth, and the fibro-cellular response similar to other reactive gingival lesions of periodontal ligament origin
(Mathur et al., 2014).
Another concept attracting much of interest regarding the origin of POF is the development of POF secondary to
fibrosis of the granulation tissue of pyogenic granuloma (PG). This concept lies on the basis that both PG and
POF share similar sex and site predilection, as well as similar clinical and histological features. Hence, these
lesions may simply be considered as variable histological responses to irritation (Babu et al., 2010).
The third pathology sharing this spectrum of chronic irritation induced gingival hyperplasia is Peripheral giant cell
granuloma (PGCG) and is known to be a related pathology to both PG and POF. Since it is known that
periodontium responds to similar irritants in a different way, it is postulated that PGCG is a more intense response
of periosteum to the irritation factors than that associated with the formation of the more common lesion that is
pyogenic granuloma (Patil et al., 2014).
