Effects of Platelet-Rich Fibrin/Collagen Membrane on Sciatic Nerve Regeneration.

ABSTRACT: Alternative treatment approaches to improve the regeneration ability of damaged peripheral nerves are currently under investigation. The aim of the current study was to evaluate the effects of leucocyte/platelet-rich fibrin (L-PRF) with or without a collagen membrane as a supporter on crushed sciatic nerve healing in a rat model. Recovery of motor function and electrophysiologic measurements were evaluated at 4 weeks postoperatively. The whole number of myelinated axons, peripheral nerve axon density, average nerve fiber diameter (µm), and G-ratio were analyzed and compered among the groups. Functional, electrophysiological, and histological evaluations showed no significant difference among the groups with the exception of the L-PRF with collagen membrane groups that showed relatively positive effects on the functional and histological nerve recovery. In addition, the collagen membrane with L-PRF can be effect in nerve regeneration.

Prevalence of osteoma cutis in the maxillofacial region and classification of its radiographic pattern in cone beam CT.

BACKGROUND: Osteoma cutis is a rare soft tissue ossification of cutaneous tissue and may be primary or secondary. In the majorityof cases it is clinically asymptomatic and may detected incidentally on radiographic examination. Cone beam computed tomography (CBCT) has can be of great assistance in the detection of this asymptomatic lesion. OBJECTIVES: In this retrospective study, the prevalence and different radiographic appearance of osteoma cutis was evaluated. MATERIALS AND METHODS: A total of 6,500 CBCT images were evaluated for the presence of osteoma cutis. Ectopic existence of calcified tissue within the soft tissue of the dermis or epidermis that was incompatible with the calcification of other anatomic structures or soft tissue calcifications was considered to be osteoma cutis. Accordingly, the detected patterns were divided into four distinct groups: (1) a single nodule, (2) plate-like lesion, (3) single or multiple depth lesion(s), trans-epidermal, and (4) multiple, disseminated lesions of various sizes known as multiple miliary. The data were evaluated in terms of prevalence and variations. The frequency, total prevalence, percentage and the prevalence of different radiographic forms of this lesion were calculated. RESULTS: One hundred and forty eight (2.27%) cases of 6,500 evaluated tomograms had osteoma cutis. Of these, 5 (0.07%) were in the form of a single nodule, 4 (0.06%) were single, plate-like lesions, 7 (0.1%) were multiple plate-like lesions, 2 (0.03%) were in the form of a deep thread-like lesion, and 130 (2%) presented as multiple disseminated lesions. CONCLUSION: According to the radiographic views, osteoma cutis may be categorized into single nodular, single or multiple plate- like, deep, and multiple disseminated forms. Of the mentioned radiogarphic patterns, the multiple disseminated form (miliary) hada higher prevalence in our study. CBCT images enable accurate evaluation of the nature and frequency of osteoma cutis.

Multifocal epithelial hyperplasia: a forgotten condition in the elderly.

Multifocal epithelial hyperplasia (MEH), also known as focal epithelial hyperplasia and Heck disease, is a relatively rare condition caused by the human papillomavirus. This case report describes a 92-year-old man who presented with multiple, asymptomatic, circumscribed, soft, flattened papules in different sizes on the retrocommissure of his lower lip. The lesions were of 2 months' duration and had the same coloration as the adjacent normal mucosa. Histopathologic examination showed orthokeratinized stratified squamous epithelium with acanthosis, some areas of club-shaped rete ridges, and a few superficial epithelial cells with koilocytic changes and a mitosoid-like appearance. A diagnosis of MEH was established. Although MEH tends to occur in the first 2 decades of life, it can be encountered in elderly patients as well.

Prevalence of Histopathologic Types of Gingival Lesions in the Iranian Population: A 22-Year Retrospective Study.

OBJECTIVES: Gingiva is one of the supporting tissues around the teeth that can be affected by various neoplastic or nonneoplastic lesions. Previous studies have examined several types of gingival lesions, but the lack of a standardized classification system has hindered meaningful comparisons. Additionally, many studies focused primarily on reactive lesions. Our study aims to contribute to the understanding of gingival lesions by investigating their prevalence across age groups, genders, sites, and by their clinical presentation. This research could lead to improved diagnostic accuracy and treatment strategies. MATERIALS AND METHODS: This retrospective study explores the prevalence of gingival lesions based on biopsies during a 22-year span. The patient's demographic details, including age, gender, and lesion's clinical presentation were systematically collected. These lesions were categorized into six groups. Descriptive statistics, χ2 test of independence, and one-way ANOVA were used for data analysis. RESULTS: Among the 7668 biopsied lesions, 684 (8.9%) lesions were located in the gingiva, with a greater occurrence in women (63.5%). Soft tissue tumors represented the most prevalent group in the gingival lesions (72.1%), and peripheral giant cell granuloma (PGCG) was the most frequent lesion (21.2%), followed by, pyogenic granuloma (19.3%), peripheral ossifying fibroma (17.8%) and focal fibrous hyperplasia (7.6%); all of which predominantly affected women, with mean ages falling in the fourth decade of life. Squamous cell carcinoma was recognized as the most common malignancy. CONCLUSION: In this study, PGCG was found to be the most common lesion in the gingiva in Iranian population. Further analysis using a unanimous categorization is required to confirm these results.

Mandibular Arteriovenous Malformation with Unusual Radiographic Appearance.

Arteriovenous malformation of head and neck is a rare vascular anomaly but when present, it is persistent and progressive in nature. It can also represent a lethal benign disease due to massive hemorrhage. There are several indications for treatment including age, location, extension and type of vascular malformation. Endovascular therapy can effectively cure most lesions with limited tissue involvement. Surgery can be used in selected cases in combination with embolization. Here, we present a rare case of arteriovenous malformation of mandible with floating tooth appearance in an 11-year-old boy patient. Given the spectrum of imaging presentations seen and the crossover with other lesions, microscopic histopathological examination is the gold standard for diagnosis.

The present and future status of oral and maxillofacial pathology in Iran: A multicenter study.

Background: At present, the status of oral and maxillofacial pathology (OMFP) in the country is not properly good. This study aimed to investigate the current status and develop practical approaches to improve occupational condition of the specialty in the future from the viewpoint of the beneficiaries. Materials and Methods: This was a descriptive cross-sectional study. The participants were oral and maxillofacial pathologists of the country (200 individuals), OMFP residents (9 individuals), and final year dental students at six dentistry school of the country at 2020 (200 individuals) through multicenter design. At the first phase, the related questionnaires were developed and assessed psychometrically. Reliability of the questionnaires, internal consistency, and repeatability were computed and confirmed. At the second phase, the survey questionnaires on the current and future condition were sent electronically to the study groups. The data were analyzed using descriptive statistical tests (mean, standard deviation, percentage) and the Pearson test using SPSS. Results: At the first phase, after primary design of the study too, 23 variables with content validity ratio below 0.56 and content validity index (CVI) below 0.79 were omitted. The questionnaire for the specialists was confirmed with Cronbach's alpha of 0.75 and intraclass correlation coefficient (ICC) as 0.83, and the questionnaire for the students and the residents were confirmed with Cronbach's alpha of 0.95 and ICC of 0.80. Results of the second phase showed that score of tendency of students to select OMFP specialty to continue education was 1.58 ± 0.57 from 5. Satisfaction score of specialists on specialized activity of this specialty is 2.7 ± 1.52 from 5. The most important reason for the students to select this specialty was "interest in being faculty member," and the "difficulty of the specialty" was the most probable reason for not selecting this specialty. The most important priority of the residents was "interest in specialty" and for the specialists was "being faculty member." The most important reason to change attitude regarding the specialty by the specialists was mentioned as "high occupational and profession responsibility as well as low income" with the score of 1.38 ± 3.99. "Fundamental revision in the educational curriculum of the specialty" with a score of 4.60 ± 0.93 from 5 was considered as the most important revisionary approach from the viewpoint of specialists. Conclusion: At present, the main problem regarding the OMPF specialty in the country is "high number of graduates and lack of the present occupational opportunities." Evaluation and validation of the relevant specialized departments, producing occupational opportunities, and fundamental revision in the educational curriculum to train well-powered specialists are necessary.

Evaluation of BIRC6 Expression in Oral Squamous Cell Carcinoma, Epithelial Dysplasia, Lichen Planus with and without Dysplasia, and Hyperkeratosis.

BACKGROUND: BIRC6, regarded as the pivotal member of the inhibitor of the apoptosis (IAP) family, has been linked to the development of different types of cancer in humans. The objective of this study was to examine the expression of BIRC6 in various oral conditions, including OLP with dysplasia (OLPD), hyperkeratosis (HK), OLP, epithelial dysplasia (ED), and oral squamous cell carcinoma (OSCC), to investigate its potential involvement in the development of OSCC and the pathogenesis and malignant transformation of OLP, which is known as a precancerous condition. METHODS: In this retrospective cross-sectional study, 99 cases, consisting of 19 cases of OSCC, 21 cases of ED, 23 cases of OLP, 20 cases of OLPD, and 16 cases of HK as the control group, were investigated regarding BIRC6 expression by immunohistochemical staining. After that, the immunohistochemical expression of BIRC6 in the epithelial compartment was analyzed. Statistical analysis was performed to investigate the relationship between the expression of BIRC6 and clinicopathological variables. The statistical analysis of the data involved the use of one-way ANOVA, post hoc Tukey, Kruskal-Wallis, Chi-square, Spearman's correlation, and Mann-Whitney tests. The significance level was set at p < 0.05. RESULTS: Positive BIRC6 staining was found in 91.7% of the subjects of OLP, 88.1% of HK, 86.1% of ED, 93% of OLPD, and 94.7% of OSCC. OSCC showed the highest BIRC6 expression (p = 0.00). The average total staining score was remarkably greater in OSCC and dysplastic lesions compared with HK (p = 0.00, p = 0.00). CONCLUSIONS: While the current study suggested that BIRC6 may play a role in the tumorigenesis of OSCC, its role in the malignant transformation of OLP has yet to be definitively established.

Immunohistochemical analysis of proliferating cell nuclear antigen and minichromosome maintenance complex component 7 in benign and malignant salivary gland tumors.

Background: Proliferation markers have been used to determine the behavior and prognosis of benign and malignant tumors; this study was aimed to compare the immunohistochemical (IHC) expression of proliferating cell nuclear antigen (PCNA) and novel marker minichromosome maintenance complex component 7 (MCM7) in common salivary gland tumors including pleomorphic adenoma (PA), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (AdCC), to find a possible significant correlation between benign and malignant tumors. Materials and Methods: In this cross-sectional study, a total of 90 cases, including 30 PAs, 30 MECs, and 30 AdCCs, were collected. The IHC expressions of PCNA and MCM7 were evaluated. Their expressions were compared with each other and between benign and malignant tumors. Statistical analysis was performed by Chi-square and Tukey's test. P value was considered 0.05. Results: Out of 30 cases of PA, 28 cases (93.3%) were PCNA positive and 28 cases (93.3%) were MCM7 positive. In the AdCC cases, 29 cases (96.6%) were PCNA positive and 29 cases (96.6%) were MCM7 positive. In the MEC cases, all cases (100%) were PCNA positive and 23 cases (76.6%) were MCM7 positive. The labeling index (LI) of MCM7 and PCNA was evaluated, and this index was lower in MCM7 LI than PCNA in all tumors. The MCM7 and PCNA expression showed a significant difference in PA and MEC (P < 0.001). Conclusion: PCNA expression was higher than MCM7 expression in salivary gland tumors. However, more studies are needed to evaluate the malignant activity of these tumors with group of markers such as MCM family members.

Unusual Case of External Juxta Coronal Odontoma.

Odontomas are benign tumors of jaws with mixed tissue, which are the result of proliferation of odontogenic epithelium and mesenchymal cells. They occur almost centrally and seldom peripherally. There is no report of such a lesion externally while attaching a tooth crown. In this case, we present a lesion on the buccal surface of the right maxillary central incisor crown, which is misconstrued with a dental overgrowth. Such cases may confuse diagnosis during clinical examination. Radiographically, such odontomas may be mistaken for various other lesions. Ultimate diagnosis should be relied upon microscopic evaluation and histopathological results.

Evaluation of VEGF expression correlates with COX-2 expression in pleomorphic adenoma, mucoepidermoid carcinoma and adenoid cystic carcinoma.

BACKGROUND: Pleomorphic adenoma (PA), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (AdCC) are the most common benign and malignant salivary gland tumors. Cyclooxygenase-2 (COX-2) is a key regulatory enzyme that its overexpression in various tumors is correlated with progression, metastasis, and apoptosis inhibition. Vascular endothelial growth factor (VEGF) is a potent angiogenic mediator that has an important role in neoplastic angiogenesis. The aim of this study was to immunohistochemically analyze the expression of COX-2 and VEGF and to compare the expression of benign and two malignant salivary gland tumors with varied structures. MATERIALS AND METHODS: In this cross-sectional study, 90 specimens including 30 cases of each tumor were retrieved. Immunohistochemical staining of COX-2 and VEGF was performed for all the samples. The percentage of positive tumor cells and staining intensity was evaluated by two pathologists blindly. Data were analyzed by Chi-square and Gamma test and P < 0.05. RESULTS: A statistically significant difference was noted between the expression and intensity of COX-2 and VEGF in PA, MEC, and AdCC (P < 0.05). A significant correlation was observed between COX-2 and VEGF expression in MEC and AdCC (P < 0.05). However, no significant correlation was found between the expression and intensity of COX-2 and VEGF with histologic grade and lymph node metastasis in MEC and AdCC (P < 0.05). CONCLUSION: High expression of VEGF and COX-2 in malignant tumors compared to PA suggested the role of both markers in malignant transformation. The significant correlation of VEGF expression with COX-2 may represent the role of COX-2 in tumor angiogenesis by modulating VEGF production.

Granular Cell Odontogenic Tumor, an Extremely Rare Case Report.

The granular cell odontogenic tumor is an extremely rare odontogenic neoplasm which about 38 cases has been reported with sufficient documentation in the literature. It has a prominent predilection to occur in the posterior of mandible of middle-aged women. Here, we report a case of mandibular granular cell odontogenic tumor in a 57-year-old female with chief complaint of swelling and tooth mobility. As rarity of these lesions, their clinical behavior and prognosis are not clear; hence, reporting more such cases may be beneficial to correct diagnosis and prevent unnecessary treatment.

CD44 expression in pleomorphic adenoma, carcinoma ex pleomorphic adenoma and their adjacent normal salivary glands.

BACKGROUND: CD44 is a transmembranous proteoglycan, with a main role of cell adhesion to other cells and to extracellular matrix involved in the preservation of three-dimensional structure of organs. Pleomorphic adenoma (PA) is a common benign salivary gland tumor, composed of myoepithelial and ductal components. Carcinoma ex-PA (CXPA) is malignant transformation of the epithelial elements in PA. The aim of this study was to evaluate CD44 expression by immunohistochemistry in these two tumors and normal salivary gland near these tumors. MATERIALS AND METHODS: In this cross-sectional immunohistochemical study, 40 paraffin blocks (formalin fixed, paraffin embedded) with thirty belonging to PA and ten blocks of CXPA and 18 paraffinized blocks of normal salivary glands' tissue adjacent to tumoral tissue (13 in the vicinity of PA and 5 in the vicinity of CXPA) were selected. Immunohistochemical expression of CD44 was observed and compared with each other. For data analysis, we used Chi-square, Kruskal-Wallis, and Mann-Whitney tests and the quantity of P values was considered 0.05. RESULTS: There was a significant difference in CD44 expression frequency between PA, CXPA, and normal salivary glands with higher expression noted in CXPA. Furthermore, expression frequency of CD44 in adjacent normal salivary gland of CXPA was significantly higher than PA. There was no significant difference in the expression of CD44 with respect to lymph node metastasis. CONCLUSION: Higher expression of CD44 in CXPA might illustrate CD44's role in malignant transformation of PA.

Ameloblastic Fibro-Odontoma in a 7-Month-Old Infant: A Case Report.

Ameloblastic fibro-odontoma is a relatively rare, benign odontogenic tumor that usually occurs in children and adolescents with unerupted teeth. This article reports an ameloblastic fibro-odontoma in the anterior mandible as a "bump on her gum" in a 7-month-old girl. This is the first case under 9 months old reported to date. Radiographic and histologic findings as well as the treatment are discussed.

Head and Neck Lymphoma in an Iranian Population.

INTRODUCTION: This study is aimed to assess the prevalence and characteristics of head and neck lymphoma in a defined group of an Iranian population. MATERIALS AND METHODS: In this retrospective study, 126,450 biopsy reports from two referral Pathology Departments, (Tehran, the capital of Iran) were evaluated. In cases with head and neck lymphoma, other variables such as age, sex, specific location of lesions, and histopathological findings were recorded. Descriptive statistics were used to measure the prevalence and characteristics of head and neck lymphoma by means of SPSS soft ware, version 18. RESULTS: In total, 513 (0.4%) cases had head and neck lymphoma (46.9% male, 27.1% female) with a mean age of 46±6.2. Of the total lesions, 200 (0.15%) were Hodgkin lymphoma and 313 (0.25%) were non-Hodgkin lymphoma. Nodular sclerosis was the most common (62.5%) histopathological subtype among Hodgkin lymphoma. In non-Hodgkin lymphoma, diffuse large B-cell lymphoma (62.3%) had the highest frequency. In Hodgkin disease, classic Hodgkin lymphocytic rich, mixed cellularity, and lymphocyte depletion were only seen in the neck compartment. Bone involvement was only found in Hodgkin nodular lymphocytic predominant variation. In non-Hodgkin lymphoma, the tongue, palate, and vestibular mucosa were affected only by diffuse large B-cell lymphoma. Jaw bones were only involved with diffuse large B-cell lymphoma compared to other bony structures. T-cell lymphoma and mucosal associated lymphoid tissue lymphoma were also found. CONCLUSION: Diffuse large B-cell lymphoma is the most common subtype of non-Hodgkin lymphoma especially in the tongue, palate, vestibular mucosa, and jaw bones.

Head and Neck Lymphoma in an Iranian Population.

INTRODUCTION: This study is aimed to assess the prevalence and characteristics of head and neck lymphoma in a defined group of an Iranian population. MATERIALS AND METHODS: In this retrospective study, 126,450 biopsy reports from two referral Pathology Departments, (Tehran, the capital of Iran) were evaluated. In cases with head and neck lymphoma, other variables such as age, sex, specific location of lesions, and histopathological findings were recorded. Descriptive statistics were used to measure the prevalence and characteristics of head and neck lymphoma by means of SPSS soft ware, version 18. RESULTS: In total, 513 (0.4%) cases had head and neck lymphoma (46.9% male, 27.1% female) with a mean age of 46±6.2. Of the total lesions, 200 (0.15%) were Hodgkin lymphoma and 313 (0.25%) were non-Hodgkin lymphoma. Nodular sclerosis was the most common (62.5%) histopathological subtype among Hodgkin lymphoma. In non-Hodgkin lymphoma, diffuse large B-cell lymphoma (62.3%) had the highest frequency. In Hodgkin disease, classic Hodgkin lymphocytic rich, mixed cellularity, and lymphocyte depletion were only seen in the neck compartment. Bone involvement was only found in Hodgkin nodular lymphocytic predominant variation. In non-Hodgkin lymphoma, the tongue, palate, and vestibular mucosa were affected only by diffuse large B-cell lymphoma. Jaw bones were only involved with diffuse large B-cell lymphoma compared to other bony structures. T-cell lymphoma and mucosal associated lymphoid tissue lymphoma were also found. CONCLUSION: Diffuse large B-cell lymphoma is the most common subtype of non-Hodgkin lymphoma especially in the tongue, palate, vestibular mucosa, and jaw bones.

Squamous Cell Carcinoma as the Most Common Lesion of the Tongue in Iranians: a 22-Year Retrospective Study.

The tongue has been globally considered as an indicator of general health for millennia. This study aimed to determine the prevalence and distribution of tongue lesions in an Iranian population. In this retrospective study, data from 6,435 oral biopsy reports over a 22-year period (1992-2014) were retrieved from archives of Oral and Maxillofacial Pathology Department, Shahid Beheshti Dental School, Tehran, Iran. These reports were analyzed according to age, sex, type of lesion and location. Prevalence of tongue lesions were reported as percentages. Out of total oral lesions, 238 (3.7%) were found in the tongue, with the incidence peak (42%) being between 41-60 years. Men constituted 53% and women 47%of patients. The youngest patient was a 3-year-old girl with pyogenic granuloma and the oldest one was a 93-year-old man with squamous cell carcinoma (SCC). SCC was the most common (25%) lesion generally found in the lateral border of the tongue with a male predilection. The second and third most prevalent lesions of the tongue were benign keratosis (frictional keratosis) (13.4%) and leukoplakia (13%).White-red lesions (38.6%) were the most frequent subgroup followed by neoplastic lesions (28%). Moreover, irritation fibroma, non-specific ulcers, squamous papilloma, and hemangioma were found as the most frequent lesions in their related subgroups.Given the high rate of SCC of the tongue in Iranian patients, this area should be examined more carefully by dental practitioners and physicians.

Lower lip numbness due to the mandibular canal narrowing after dental reimplantation: A case report.

Mandibular canal is the most important anatomical landmark in the body of mandible which always must be considered for implant surgery in posterior mandibular region. Damage to vessels and inferior alveolar nerve that passes through the mandibular canal can cause problems such as hemorrhage and neurosensory disturbances. Damage to the mandibular canal can occur during implant surgery. Depending on the severity of injuries, it would result in temporary or permanent neurosensory disturbances. We have reported a case that mandibular canal narrowing occurred following implant surgery and resulted in anesthetic and hypoesthetic areas in the lower lip. Patient had a history of implant surgery in the region of teeth numbered 30 and numbered 31. The inserted implant failed after 6 years, and reimplantation was done in this area, but due to lower lip numbness in the right side, the second implant was removed, and another implant was inserted in the region of the tooth numbered 32. After 2 years, right lower lip numbness was reported again by the patient. Cone beam computed tomography images showed canal narrowing in the region of the tooth numbered 31 where the second implant was inserted. It seems that the main cause for anesthesia and hypoesthesia in this patient is canal narrowing due to damage during implant replacement and removal.

Designing and Implementation of a Course on Successful Dental Practice for Dentists.

OBJECTIVES: We aimed to design, implement and evaluate the efficacy of a comprehensive course on non-clinical competencies that dentists must possess for a successful dental practice. MATERIALS AND METHODS: In this interventional before-after study an expert panel of five academic staff members and five general practitioners derived the topics for a course on successful dental practice, and aggregated them in the form of a two-day course. It was held for 46 randomly selected dentists in January 2010, at the School of Dentistry, Tehran University of Medical Sciences. The participants completed an anonymous questionnaire asking about their self-perceived need to receive training in each of the proposed topics and their self-assessed knowledge about each topic before and after attending the course. RESULTS: Participants gave a higher priority to the necessity of training on "ergonomics and professional health" and communication skills in post-test compared to pre-test (P<0.05). The self-assessed knowledge of dentists improved significantly after attending the course in seven domains: ergonomics and occupational health, workplace design, documentation principles and IT applications in dentistry, national rules and regulations of dental practice, medical emergencies, dental ethics and communication skills (P<0.05). More than 70% of the participants were completely satisfied or satisfied with practical implication of the course, conformity of the contents with the title and course settings. CONCLUSION: The designed course seemed to be successful in revealing the need of participants for further education. Considering the high satisfaction rate of the attendants, this course can serve as a model for continuing education purposes.

Evaluation of alveolar crest bone loss via premolar bitewing radiographs: presentation of a new method.

PURPOSE: This study aimed to assess the interdental bone level in premolar bitewing radiographs while retracting the cheeks. METHODS: Seventy-two horizontal bone defects were created on dried mandibles and maxillae. The distance from the bone level to the cement-enamel junction of premolars was detected by a modified digital caliper (considered the gold standard). The reliability of all radiographs was assessed by intraclass correlation coefficient (ICC), and the validity was compared to the gold standard using the analysis of variance test. P-values less than 0.05 were considered statistically significant. RESULTS: This study showed that the reliability of radiographs without a cheek simulator and with 0.16 second exposure time was significantly higher than that of the two other groups (ICC=0.96 compared to 0.93 and 0.88, respectively). The results from the radiographs without a cheek simulator and with 0.16 second exposure time were more similar to the gold standard measures than those of the two other groups, although the difference was not statistically significant. CONCLUSIONS: Retracting the buccal soft tissue plays an important role in increasing the accuracy of radiographs in detecting the interdental alveolar bone level and produces more accurate results than increasing the exposure time, although it does not have a significant role in reliability of results.