Immunohistochemical expression of Cyclooxygenase 2 reflects the proliferative activity in the epithelium of odontogenic lesions

Purpose: Odontogenic cysts and tumors comprise a major component of lesions of the oral and maxillofacial region. The pathogenesis of these lesions involves the interaction between the odontogenic epithelium and the ectomesenchyme. However, the clinical behavior of these biological entities is unpredictable. The aim of this study was to evaluate the role of Cyclooxygenase 2 (COX-2) in the pathogenesis and prognostication of odontogenic lesions.Material and method: : In this study formalin-fixed paraffin-embedded tissue section of Odontogenic Keratocyst (n=10) Dentigerous cyst (n=10), Radicular cyst (n=10) and unicystic ameloblastoma (n=10) were immunohistochemically stained with COX-2 (NCL2-COX-2- 4H12) and with Ki 67 (Ki-67 GM001) using standard staining protocols. The cytoplasmic expression of COX-2 in all the lesions was semi-quantitatively assessed. The pattern of expression of COX-2 among the different odontogenic lesions was statistical analyzed using the ANOVA test and the chi-square test.Results: All the 40 odontogenic lesions that were evaluated expressed COX-2 immunohistochemically. A high number of odontogenic epithelial cells expressed COX-2 in most of the odontogenic keratocyst, radicular cyst and unicystic ameloblastomas. The expression of COX-2 was significantly (p=0.036) higher in Unicystic Ameloblastomas and Radicular cyst compared to that of Odontogenic Keratocyst and the dentigerous cyst.Conclusion: The recognition that expression of COX-2 by odontogenic epithelial cells may indeed shed a new light on the biological mechanisms involved in the development of these benign yet aggressive lesions of the jaws. An insight into the molecular interactions occurring in the odontogenic epithelium will aid in better management of these lesions.

A retrospective analysis of oral and maxillofacial pathological lesions in a group of Egyptian children over 21 years

Objectives The goal of the current study was to evaluate the relative frequency of oral and maxillofacial pathological lesions among Egyptian children. Materials and methods Records of biopsies submitted to the department of oral and maxillofacial pathology from the year 1999 to 2019 were retrieved and reassessed for all cases under the age of 18 years. Information on age, sex, location of the lesion, and the histopathologic diagnosis was analyzed. Results Over the course of twenty-one years, 1108 specimens were analyzed where reactive soft tissue lesions, which accounted for 397 (35.8%) of all cases ranked the highest presented category, followed by inflammatory odontogenic cysts, which accounted for 213 cases (19.2%). With 208 cases, the inflammatory radicular cyst was on the top of the most common 20 lesions, followed by pyogenic granuloma (160 cases). Malignancy was found in 19 cases, with soft tissue tumors (10 cases) being the most common, followed by salivary gland (5 cases) and bone pathologies (4 cases). Conclusions The frequency of oral and maxillofacial pathological lesions among Egyptian children increased over the years but remained consistent with global trends. Clinical relevance This is the first study evaluating the relative frequency of oral and maxillofacial pathological lesions among Egyptian children and provides an insight into the most commonly encountered pediatric pathologies. This may aid in the understanding of the most prevalent oral lesions that impact the pediatric population, as well as providing the key to early detection of lesions.

Inflammatory Odontogenic Cysts

Cystic conditions of the jaw cause bony destruction and may cause resorption or displacement of adjacent teeth. Odontogenic cysts have developmental or inflammatory origins. To describe in detail the inflammatory odontogenic cysts, a manual search was done in hard copy books of oral and maxillofacial pathology, and an electronic search was done in the google website, oral and maxillofacial pathology E-books, PubMed, Research Gate, Academia, and Google scholar using the keywords "odontogenic cysts," "classification of the odontogenic cysts," "radicular cyst," "periapical cyst," "lateral inflammatory cyst," "residual cyst," "paradental cyst," "collateral inflammatory cyst," "treatment of inflammatory odontogenic cysts," and matching each odontogenic inflammatory cyst subtype with these words "gross description," "pathogenesis," "microscopical," clinical," "radiographical" appearance. Articles published till February 2021 were included in this review. In conclusion, an accurate diagnosis of an inflammatory odontogenic cyst requires information relative to its clinical, radiographical, macro- and microscopical findings. In many instances, two cysts that are classified differently may exhibit similar histopathological features. In such cases, clinical and radiographic findings are necessary to make a precise diagnosis.

Modern Surgical Methods of Treatment of Odontogenic Jaw Cysts (Literature Review and Own Data)

The purpose of the study was to analyze the data of modern domestic and foreign professional literature, which are devoted to new surgical methods of treatment of odontogenic cysts, to highlight the results of own clinical studies on the effectiveness of developed methods of cystectomy in jaw bones and their anesthesia. Materials and methods. Analytical and bibliosemantic methods were used in the research. The search for scientific information on medical topics for the period from 2010 to 2021 was carried out in the databases of electronic searching systems. Results and discussion. The use of standard techniques of conduction anesthesia of the trigeminal nerve is not always effective during cystectomy in the lateral parts of the mandible, due to the variability of branching of the trigeminal nerve, the possibility of additional innervation of the jaw branch from the superficial cervical plexus. Taking into account these anatomical factors, it is painless to perform a cystectomy of odontogenic cysts on the mandible. During oronasal cystectomy of odontogenic cysts that have grown into the nasal cavity it is advisable to block the nasopalatine nerve in the middle nasal passage. Modified methods of marsupialization can be used as an independent method of treatment of odontogenic cysts of large size, or be combined with radical removal of the cyst membrane. The use of ultrasound medical techniques reduces the risk of damage to adjacent soft tissues during enucleation of bone membranes in complex topographic and anatomical areas. The use of modern laser technologies and medical radiophysical equipment can increase the effectiveness of surgical treatment of odontogenic jaw cysts. The use of endovideosurgery techniques reduces the percentage of intraoperative complications. The introduction of computer spatial imaging of anatomical objects in dental practice has made it possible to develop new surgical technologies for precision-guided osteotomy and resection of the tips of the roots of masticatory teeth adjacent to the shells of radicular jaw cysts. Conclusion. In modern clinical practice, technical developments are used, which are based on the latest advances in laser optics, radio physics, bioacoustics, computer technology, which minimizes injuries during cystectomy operations, reduces the frequency of intraoperative complications. Individual-anatomical features of innervation of the maxillofacial area should be taken into account during local anesthesia, cystectomy and cystotomy operations in the jaw bones

Odontogenic Cysts and Tumors of Maxilla and Maxillary Sinus (A Clinicopathological Analysis)

Background: Knowledge about the prevalence and distribution of pathologies in a particular location is important when a differential diagnosis is being formulated. The aim of this study was to describe the prevalence and the clinicopathological features of odontogenic cysts and tumors affecting the maxilla and to discuss the unusual presentation of those lesions within maxillary sinus. Materials and Methods: A multicenter retrospective analysis was performed on pathology archives of patients who were diagnosed with maxillary odontogenic cysts and tumors from 2010 to 2020. Data were collected with respect to age, gender and location. Result: A total of 384 cases was identified, 320 (83.3%) cases were diagnosed as odontogenic cysts and 64 (16.6%) as odontogenic tumors. The mean age was 30.5 years with a standard deviation of 16.2 years. Male patients were more commonly affected (n=220, 57.3%). Radicular cyst was the most common cyst (n=205, 64.1%), while the most common tumor was odontoma (n=14, 21.9%) and dentigerous cyst was the most common lesion to present within the maxillary sinus. Conclusion: This study indicates that there are some geographic similarities and differences in regard to distribution of odontogenic cysts and tumors in maxilla and it raises awareness of their presentation within maxillary sinus especially if there is an association with an ectopic or adjacent impacted tooth.

Dentigerous cyst in the maxilla: case report in a pediatric patient

Dentigerous cysts are the second most common odontogenic cysts of the jaws, and sometimes inhibit the eruption of teeth. Almost all of the dentigerous cyst encloses the crown of an unerupted tooth and the radiolucent area is attached to the tooth at the cementoenamel junction. Dentigerous cyst is more common in male patients and most commonly develop in the second and third decades of life. Clinically, a localized swelling of the alveolar bone can be detected, however, dentigerous cysts can be asymptomatic during a long period of time, leading to a significant destruction of bone. The conventional treatment plan is cyst removal and marsupialization. Marsupialization therapy can be useful to promote the spontaneous eruption of the involved tooth within the cyst. However, tooth eruption does not always occur spontaneously after marsupialization. This article aims to report a clinical case of the diagnosis and treatment of a dentigerous cyst in the maxilla associated with an unerupted canine in a pediatric patient and discussion of the treatment performed.

Differential Expression of Claudin in Odontogenic Cysts

Objective This study aimed to analyze claudin-1, -4, and -7 expression in different types of odontogenic cysts (odontogenic keratocysts [OKCs], dentigerous cysts [DCs], calcifying odontogenic cysts [COCs], and radicular cysts [RCs]) as well as its association with OKC recurrence. Materials and Methods Seventy samples of odontogenic cysts samples were immunohistochemically stained to detect claudin-1, -4, and -7 expression. Patient information and OKC recurrence data were recorded. The staining was analyzed semiquantitatively and categorized based on the pattern and percentage of positively stained cystic epithelial cells. Statistical Analysis Expression of different claudins between groups was analyzed using the Kruskal–Wallis test with Dunn's test, followed by post hoc pairwise comparison. The association between claudin expression and OKC recurrence was analyzed by the Mann–Whitney U test. Correlations among claudin expression were examined with Spearman's correlation coefficient. Level of significance was at p < 0.005. Results Claudin-1 was widely expressed in every odontogenic cyst. Most DCs (50%) expressed claudin-1 in more than 75% of cells, as did RCs (65%), while most OKCs (50%) expressed claudin-1 in 26 to 50% of cells. Most COCs (50%) expressed claudin-1 in 51 to 75% of cells. Every sample of OKC and RC was positive for claudin-4, but no sample showed staining in more than 51% of cells. Every odontogenic cyst was positive for claudin-7. DCs (35%), OKCs (55%), and RCs (40%) mostly showed staining in 26 to 50% of cells. High claudin-1 expression was shown in COCs, DCs, and RCs, while low expression of claudin-4 was shown in every odontogenic cyst. For claudin-7, the expression is high only in COCs. Claudin-1 and -4 was significantly different among each odontogenic cyst. High expression of claudin-1 was correlated with OKC recurrence. The correlations of claudin-1 with claudin-7 expression and claudin-4 with claudin-7 expression were significant in DCs. In COCs, claudin-1 and claudin-7 expression was significantly correlated. Conclusions The expression of claudin-1, -4, and -7 was present in every odontogenic cyst, but the proportion of positive staining cells was different. Expression of claudin-1 is associated with OKC recurrence. Dysregulation of claudin expression may play a pathogenic role in cyst pathogenesis.

Evaluation of the Response of Odontogenic Keratocysts to Tube Decompression: A Clinical and Radiographic Study

Background and Objectives: Keratocyst is the most aggressive entity of odontogenic cysts with a high tendency to recure after enucleation. This study was conducted to assess the effect of decompression in inducing cyst shrinkage before enucleation. Materials and Methods: A prospective non-randomized study was conducted on 11 patients with odontogenic keratocyst the department of maxillofacial surgery, university-affiliated teaching hospital, between February 2016 to March 2021. There were 8 males and 3 females, with a mean age of 57 years. Tube decompression was conducted as a preliminary treatment, before enucleation. The size of the cyst was measured on orthopantomograph, before, during, and after decompression. The percentage of reduction was calculated, as well as, the correlation of cyst regression with the initial size of the lesion and age of the patient. Results: The mean duration time of decompression was 208 days (152-316). The pre- and post-decompression size of the cysts was 14.51 cm2 (5.63 cm2 -32.37 cm2) and 6.69 cm2 (1.76 cm2-14.81 cm2), respectively. The total and monthly percentage of reduction in the size of the cysts was 54.39% (37.29%-76.37%) and 7.84% (4.45%-11.27%), respectively. The initial size of the lesion has no significant correlation with the percentage of reduction, whereas the age of the patients showed a significant negative correlation with the percentage of reduction. Conclusion: Decompression is a well-tolerated conservative treatment, which leads to marked reduction in cyst dimensions. It induces shrinkage of the cyst away from anatomical structures, to reduce the morbidity associated with subsequent surgical treatment.