Mast cells density in fibrotic capsule of enchondroma and well-differentiated chondrosarcoma: a method for histopathologic differentiation

An enchondroma is a benign and a well-differentiated chondrosarcoma is an invasive chondroid tumor with high recurrence potential. In spite of biologic differences, these two tumors have very similar histopathologic appearance. It has been shown that the biologic nature of the connective tissue around benign and malignant tumors varies in the number of mast cells. The aim of this study was to study the histopathologic distinction of enchondroma and well-differentiated chondrosarcoma using the density of the mast cells in fibrotic capsule. Twelve enchondroma and 15 well-differentiated chondrosarcoma were collected from Pathology department of Cancer Institute and Central Pathology department of Imam Khomeini Hospital in Tehran. 3 micron paraffin embedded tissue sections were stained by toluidine blue for mast cells counting. Mast cells were counted in fibrous capsule of all cases. Mast cells counts were accomplished in 10 high power fields .The average number of mast cells in 10HPF was determined as an index for each lesion. Mann-Whitney U test was used for statistical analysis. Mean index in enchondroma and well-differentiated chondrosarcoma groups were 0.1 +/- 0.12 and 0.31 +/- 0.33 respectively, showing a significant difference between number of mast cells in the fibrotic capsule in these two lesions [p=0.028]. Comparison of the corresponding points in ROC curve, showed a cut-off point = 0.15, with positive predictive value of 61%, negative predictive value 71%, specificity of 33.3% and sensitivity of 66.7%, [p=0.025]. Average density of the mast cells in the surrounding fibrotic capsules of enchondroma and well-differentiated chondrosarcoma along with other criterions, could be a beneficial factor for histologically differentiation between these two lesions

Evaluation of relationship between periodontal pocket on the distal surfaee of mandibular second molar and pattern and depth of third molar impaction

One of the asymptomatic lesions associated with an impacted mandibular third molar is localized periodontal pocket on the distal surface of mandibular second molar. In this study, relationship between periodontal pocket on the distal surface of mandibular second molars and pattern and depth of impaction is evaluated. The study was performed experimentally. A group of 100 patients, referring to surgical department of shahed dental school and shahid montazeri clinic [1386-87], were selected sequentially for the purpose. Pattern and depth of mandibular third molar impaction were recorded in studying form according to O.P.G radiograph. The impacted third molars were extracted by means of a clinical indication and depth of periodontal pocket was measured 4-24 months after surgical extraction. Statistical software of SPSS for windows was used for data analysis, using Kruskal-Wallis and Mann-Whitney tests for assessing relationship between periodontal pocket depth and pattern and depth of mandibular third molar impaction. The age of the patients was 24.S +/- 7, 55 individuals [55%] were females while the next 45 individuals [45%] were males. There was statistically significant difference between periodontal pocket depth and pattern and depth of mandibular third molar impaction. [p<0.001] Based on the findings of this study, deep periodontal pockets on the distal surface of a mandibular second molar, is mostly associated with horizontal, mesioangular and class C impacted third molar. So, more attention should be given to the detection of signs of periodontal pockets on the distal aspects of mandibular second molars when assessing the clinical state of the adjacent impacted third molars, because pattern and depth of impaction could be very determinative