رضا زارع محمودآبادی

The present study aimed to evaluate vascular density in giant cell lesions with different biologic behavior. Therefore, CD34 expression in central and peripheral giant cell granulomas and the aneurysmal bone cyst was evaluated by immunohistochemistry.

A total of 15, 15, and 8 samples of PGCG, CGCG, and ABC were selected from the archives of the Dentistry School of Mashhad University and Ghaem Hospital, Mashhad, Iran, respectively. Immunohistochemical evaluation of CD34 expression was performed according to the manufacturer's instructions to assess microvessel density (MVD). MVD was calculated in five microscopic fields and the mean MVD of samples was evaluated. Findings were analyzed using t-test, ANOVA, and Pearson’s correlation coefficient.

CD34 expression was 31.53, 31, and 26.40 in CGCG, ABC, and PGCG samples, respectively. Although the highest MVD was in CGCGs, no statistical difference was observed between the studied groups (0.270).

According to the findings of the present study, evaluation of microvessel density with CD34 expression indicates no pathogenesis and different biological behavior of the studied groups. Therefore, further research seems necessary.

Resistance of oral pathogenic bacteria to chlorhexidine mouthwash is increasing; therefore, researchers are looking for a replacement of chlorhexidine with suitable herbal mouthwash. This study aimed to investigate the antimicrobial effect of hydroalcoholic extract of Plantago major (a native strain of Khorasan, Iran) with and without zinc oxide nanoparticles on Streptococcus mutans.

In this in vitro study, the samples were tested in two groups of hydroalcoholic extract of Plantago major leaves with and without zinc oxide nanoparticles. To determine the minimum bactericidal concentration and minimal inhibitory concentration, agar diffusion and broth dilution methods were applied, respectively. A concentration of 500 ppm zinc oxide nanoparticles with a 0.4 nm diameter was used continuously in all stages of the experiment. The materials used in this study consisted of a standard strain of Streptococcus mutans (ATCC 25175), chlorhexidine 0.2% as a positive control, and distilled water as a negative control.

The mean diameter of the growth inhibition zone was obtained as 15±1 mm for the hydroalcoholic extract of Plantago major leaves with zinc oxide nanoparticles at a concentration of 1.56 mg/ml. The same extract at the same concentration, however without zinc oxide nanoparticles, showed the mean diameter of growth inhibition zone of 7.67±0.57 mm. The results of the t-test were indicative of a significant difference between the two groups (P-value<0.001).

In this study, the antimicrobial effect of Plantago major leaves extract with or without zinc oxide nanoparticles was well established. This research is peculiar since it revealed the effectiveness of low concentrations of this plant in killing Streptococcus mutans.

Ameloblastoma is a prevalent odontogenic maxillofacial tumor. Human papillomavirus (HPV) is considered to be one of the main risk factors for ameloblastoma. The current research aimed to investigate the presence of HPV in the ameloblastoma of jaw samples using the polymerase chain reaction (PCR).

This study was conducted on 77 formalin-fixed and paraffin-embedded tissue blocks, which were obtained from the archives of the Department of Pathology at Mashhad Dentistry School and Ghaem Hospital in Mashhad, Iran. Deparaffinization and DNA extraction in the samples were performed in accordance with the instructions of the YTA genomic DNA extraction mini kit. After PCR, the presence of HPV was evaluated in the samples. Data analysis was performed in SPSS version 16 using descriptive statistic (frequency distribution tables and charts), Chi-square, and logistic regression.

Among 77 lesions, 20 cases were follicular, four cases were acanthomatous, three cases were basal cells, eight cases were desmoblastic, 17 cases were unicystic, and 25 cases were plexiform. Moreover, five samples (6.5%) were positive for HPV. HPV was detected in one follicular case, two unicystic cases, and two plexiform cases.

Considering the low prevalence of HPV in the examined lesions, it could not be concluded that the virus was involved in the etiology and pathogenesis of the lesions. Therefore, further investigations must be conducted on larger sample sizes for more accurate results

Complications resulting from removable denture consist of a wide range of oral mucosal lesions, the prevention of which and dealing with their complications are both the dentist’s and the patient’s responsibilities. The aim of this study was to evaluate the frequency of denture hyperplasia in Mashhad Dental School.

In this descriptive-cross sectional study, we aimed to assess the incidence of denture hyperplasia lesions on biopsies received in the Department of Pathology of Mashhad Dental School since 1357 till 1387 Collected data were statistically analyzed using the SPSS software and tables and diagrams were generated.

The lesions results from denture were 5.6% of all lesions. From 462 cases, 368 cases occurred in women and 94 in men. In 97.8% of patients IFH and in 2.2% of patients IPH were found. In this study, IFH with 452 cases were observed more frequently in the female (79.7%) than the male subjects and in the 5th and 6th decades (68.2%). The common location of this lesion was mandible (69.9%) and anterior region (85.7%). Lesion enlargement (4.6%), Pain and burning (9%) sensation were recognized as the two most common referring factors to the dentist associated with these lesions.

In this study the IFH had the highest frequency and the IPH occurred only in a small percentage of lesions. Overall, the denture hyperplasia was more common in females in the 4th and 5th decades. The highest frequency of referring to the Dental School was between years 1367-1376 (54.9%).