Evaluation of mast cell counts and microvessel density in reactive lesions of the oral cavity

Background. Reliable immunohistochemical assays to assess the definitive role of mast cells (MCs) and angiogenesis in the pathogenesis of oral reactive lesions are generally not available. The aim of the present study was to evaluate mast cell counts (MCC) and microvessel density (MVD) in oral reactive lesions and determine the correlation between MCC and MVD. Methods. Seventy-five cases of reactive lesions of the oral cavity, including pyogenic granuloma, fibroma, peripheral giant cell granuloma, inflammatory fibrous hyperplasia, peripheral ossifying fibroma (15 for each category) were immunohisto-chemically stained with MC tryptase and CD31. Fifteen cases of normal gingival tissue were considered as the control group. The mean MCC and MVD in superficial and deep connective tissues were assessed and total MCC and MVD was computed for each lesion. Results. Statistically significant differences were observed in MCC and MVD between the study groups (P < 0.001). MC tryptase and CD31 expression increased in the superficial connective tissue of each lesion in comparison to the deep con-nective tissue. A significant negative correlation was not found between MCC and MVD in oral reactive lesions (P < 0.001, r = -0.458). Conclusion. Although MCs were present in the reactive lesions of the oral cavity, a direct correlation between MCC and MVD was not found in these lesions. Therefore, a significant interaction between MCs and endothelial cells and an active role for MCs in the growth of oral reactive lesions was not found in this study

Mandibular Fracture Associated with a Dentigerous Cyst: Report of a Case and Literature Review

Background and aims. Pathological fractures are rare in the maxillofacial region and account for less than 2% of all frac-tures in this site. They are defined as fractures that take place when bone has been weakened by an underlying pathologic process. Among all pathoses, cysts (although so common in the maxillofacial region) constitute a very small part. Here we report a case of a dentigerous cyst in a 38-year-old man.The cyst was associated with a mandibular second premolar tooth and resulted in a pathologic fracture. Excision of the lesion was performed and bony union was observed after 6 months. In the literature review, only one case of dentigerous cyst causing pathologic fracture was found. In addition to the report of the present case, pathologic fractures associated with all types of odontogenic cysts (totally just 12 cases) are reviewed in this article to provide a comprehensive and detailed collection

Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst

Purpose: The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. Methods: 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. Results: RC showed the highest mean numbers of MCs and microvessels (p<0.05). The subepithelial zones of all cysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). Conclusion: Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear

Consistency Rates of Clinical Diagnosis and Histopathological Reports of Oral Lesions: A Retrospective Study

Background and aims. A correct diagnosis is the most important step in the treatment of oral lesions and each oral lesion has specific clinical features that provide clinical diagnosis; however, some of these features are common among different lesions. In these situations, biopsy and histopathological examination are indicated. The aim of this study was to evaluate the relationship between clinical and histopathological diagnosis of patients referred to the Department of Oral Pathology, Tabriz Faculty of Dentistry, from 2009 to 2011. Materials and methods. In this retrospective study, individual data and clinical findings of 311 patients who had been referred to the Department of Oral Pathology during a three-year period were collected through questionnaires and compared with histopathological reports. Data were analyzed by using chi-squared and Fisher's tests. Results. In 80.7% of the cases the clinical diagnosis of the lesions was consistent with pathology reports. In 19.3% of the cases, the clinical diagnosis of the lesions was not confirmed histopathologically. The greatest consistency was observed for lichen planus (100%) and inflammatory fibrous hyperplasia (epulis fissuratum) (94.3%). Conclusion. Although great consistency rates were observed in this study between clinical diagnoses and pathology reports, there was also a significant disagreement with the literature, indicating that comprehensive clinical examination, high consistency with oral lesion features and effective cooperation between surgeons and pathologists are necessary

Nucleolar Organizer Regions in Oral Squamous Cell Carcinoma

Background and aims. Several diagnostic methods are being employed to detect benign and malignant lesions, one of which is silver nitrate staining for organizer regions. The number of nucleolar organizing regions (NORs) can be used to show the degree of cell activity or metabolism in pathologic lesions. This study was designed to evaluate NORs as determinants of precancerous and squamous cell carcinoma. Materials and methods. A silver colloid technique was applied on paraffin sections of 40 cases of oral squamous cell carcinoma and 25 cases of precancerous lesions; 15 specimens of normal epithelium were selected for the control group. After staining with silver nitrate, argyrophilic nucleolar organizer regions (AgNORs) were counted in 100 epithelial cells in three groups with the use of an oil immersion and ×1000 objective lens. One-way ANOVA and a post hoc Tukey test were used for statistical analysis. Results. The mean numbers and standard deviations of AgNORs were 1.58 ± 0.76 in normal epithelium, 2.1 ± 1.05 in precancerous lesions and 2.43 ±1.33 in squamous cell carcinoma (SCC). There were statistically significant differences in AgNORs numbers between the groups (P<0.001) and significant differences in precancerous lesions between dysplastic and non-dysplastic epithelia (P<0.001). The mean AgNORs count per nucleus increased from healthy epithelium to precancerous lesion to SCC. Conclusion. This study suggests that the silver staining technique for the detection of NORs (AgNOR) can be used to distinguish precancerous lesions and benign and malignant lesions

Evaluation of the Position and Course of the Posterior Superior Alveolar Artery by Cone-Beam Computed Tomography in an Iranian Population

Background and Aim: Understanding the vascular anatomy of the maxillary sinus plays an important role in the success of sinus grafting and determining the location of lateral osteotomy. The aim of the present study was to localize the posterior superior al-veolar artery (PSAA) and to measure the distance from this vascular canal to the maxil-lary sinus floor and alveolar crest by cone-beam computed tomography (CBCT). Materials and Methods: This study was conducted on 600 CBCT scans. The distance from the inferior border of the PSAA to the maxillary sinus floor and alveolar crest was measured and the position of this vascular canal was evaluated. The distance from the vascular canal to the maxillary sinus floor was also compared in dentulous and edentulous patients. The results were analyzed by repeated measures ANOVA and Tukey’s post-hoc test. Results: The PSAA was detected on 150 scans. The intraosseous position of the canal was seen in 51.30% of the cases. There were insignificant differences among the distances from the vascular canal to the maxillary sinus floor in different dental areas. However, there were significant differences in the distances from the vascular canal to the alveolar crest in different regions (P<0.001). Conclusion: In this study, the PSAA was detected in 25% of the cases. The smallest distance between the vascular canal and maxillary sinus floor was observed in the first premolar and first molar regions, respectively. Determining the position of the PSAA by CBCT is useful for reducing perioperative bleeding; therefore, CBCT is recommended as a routine imaging technique prior to sinus lifting

Schwannoma in the Midline of Hard Palate: A Case Report and Review of Literature

Schwannoma is a benign encapsulated slow-growing tumor that originates from Schwann cells of the peripheral nerve sheath. It usually occurs in the head and neck; however, it is rare in the oral cavity. The tongue is the most common site of intraoral schwannomas, followed by the floor of the mouth, palate, gingiva, vestibular mucosa, lips and mental nerve area. We report a rare case of schwannoma in the midline of hard palate with ulcerated surface in a 21-year-old male with a twomonth history of a painless swelling on his palate. Clinical, radiographic and histopathological features along with differential diagnosis and treatment are also discussed

Prevalence of Head and Neck Tumors in Children under 12 Years of Age Referred to the Pathology Department of Children’s Hospital in Tabriz during a 10-year Period

Background and aims. Head and neck tumors are the most common complaints of people referring to different medical sections, especially in children. The aim of this study was to evaluate the prevalence of these tumors in children less than 12 years of age to provide a better perspective for future studies. Materials and methods. All the files in Department of Pathology at Tabriz Pediatric Hospital from 2001 to 2011 were screened for head and neck tumors in children under 12 years of age. Data including age and gender as well as the type, the location, and benign/malignant characteristic of the tumor were recorded. Data were analyzed by SPSS 15 statistical soft-ware, using descriptive statistics and chi-square test. Results. A total of 160 cases were identified. Most of the tumors were benign (68%) and most of the tumors occurred in the neck region (41%). The most frequent benign and malignant tumors were lymphangioma and non-Hodgkin lymphoma, re-spectively. The majority of benign tumors were found in children younger than 2 years old (P=0.007), but there was no age predilection for malignant tumors. Conclusion. According to our results, benign tumors were more prevalent than malignant ones. Although a low rate of benign tumors in males shows that more attention should be paid to the early diagnosis of head and neck tumors

Therapeutic Efficacy of Orally Delivered Doxorubicin Nanoparticles in Rat Tongue Cancer Induced by 4-Nitroquinoline 1-Oxide

Purpose: Oral cancer is one of the most significant cancers in the world, and squamous cell carcinoma makes up about 94% of oral malignancies. The aim of the present study was to compare the efficacy of doxorubicin plus methotrexate - loaded nanoparticles on tongue squamous cell carcinoma induced by 4NQO and compare it with the commercial doxorubicin and methotrexate delivered orally on seventy SD male rats. Methods: 70 rats were divided into five groups. During the study, the animals were weighed by a digital scale once a week. Number of mortalities was recorded in the data collection forms. At the end of the treatment, biopsy samples were taken from rat tongues in order to evaluate the severity of dysplasia and the extent of cell proliferation. The results were analyzed using ANOVA, descriptive statistics and chi-square test. Results: No statistically significant difference was found in the mean weight of five groups (p>0.05). No significant relationship was found between groups and mortality rate (P = 0. 39). In addition, there was a significant relationship between groups and the degree of dysplasia (P <0.001). The statistical analysis showed a significant relationship between groups and the rate of cell proliferation (p <0.001). Conclusion: The results of the present study showed that the use of doxorubicin plus methotrexate - loaded nanoparticles orally had more therapeutic effects than commercial doxorubicin plus methotrexate