Abstract
Comparative study of bone and lamellar bone formation in Peripheral Giant Cell Granuloma and Peripheral Ossifying Fibroma
 Dr. SH. Ghasemi Moridani* - Dr. H. Mahmoodi Chenari*
*-Assistant Professor of Oral and Maxillofacial Pathology Dept.-Faculty of Dentistry-Guilan University of Medical Sciences.
**- Dentist.
 Background and Aim: Peripheral Giant Cell Granuloma (PGCG) and peripheral ossifying fibroma (POF) are reactive gingival lesions producing bony tissue. This bony tissue can be woven or lamellar. The aim of this study was to compare the percent of bone and lamellar bone formation in PGCG and POF.
Materials and Methods: Twenty – five cases of PGCG and twenty – five cases of POG were selected from the files of Oral pathology department of Tehran Faculty of Dentistry and Razi Pathobiology laboratory of Rasht. Clinical data including age, gender and location of lesion were recorder. The percent of bone and lamellar bone formation were determined using light microscope and polarized light. In order to compare the percentage of bone formation in lesions t – test was used and Pearson correlation coefficient was used to investigate the relationship between the mentioned variables and age.
 Results: The percent of bone and lamellar bone formation in PGCG were 9.06% and 45.05%, respectively and in POF were 8.72% and 35.18%, respectively showing no statistically significant difference in these two lesions. There was no relationship between the percent of bone formation and age, gender and also location of lesion in each of them. Mean volume of PGCG and POF lesions were 3.18cm3 and 1.34cm3, respectively.
 Conclusion: There was no statistically significant difference in the percent of bone formation between PGCG and POF. However, considering the difference between volumes it appears that bone formation may be greater in POF.
Key words: Peripheral ossifying fibroma – Peripheral Giant Cell Granuloma – Bone formation - Lamellar bone