Histopathological study of radicular cysts diagnosed in a Brazilian population

Maxillary Postsurgical Ciliated Cysts (PSCCs): A Series of Three Cases

Introduction

A postsurgical ciliated cyst (PSCC) is an epithelial cyst that usually develops in the maxilla, although in rare cases, it can affect the mandible or other facial bones. The typical age of diagnosis is 40-50 years, with no gender prevalence, and the mean cyst development occurs approximately 10-15 years following a surgical or traumatic event. Some epithelial respiratory cells can be trapped into the bone tissue during maxillary surgical procedures or maxillary fractures. The pathogenetic mechanism can be attributed to an inflammatory process that stimulates epithelial proliferation, leading to cyst expansion caused by osmotic pressure difference.

Methods

This study presents case series involving three surgical ciliated cysts located in the left maxilla, affecting two female patients (aged 49 and 55 years) and one male patient (aged 39 years). In all three cases, symptoms such as pain or swelling were mild and not consistently present. Two cases showed cyst development 10 and 15 years after implant placement, while one case was not associated with any surgical or traumatic event. CT scan identified well-defined unilocular lesions in the maxillary bone in each patient.

Results

Histopathological examination of the surgical specimens confirmed the suspected diagnosis of a PSCC of maxilla. The cystic walls consisted of fibrous connective tissue with chronic inflammatory infiltrate, lined exclusively by a thin layer of ciliated pseudostratified columnar epithelium. In the third patient, it was not possible to rule out an unusual radicular cyst.

Conclusions

Although PSCCs are not commonly encountered in daily practice, clinicians should consider this possibility including it in the differential diagnosis of odontogenic jaw cysts and benign jaw tumors, particularly in patients who have undergone previous surgeries in the maxillary area.

Expression of epithelial growth factors and of apoptosis-regulating proteins, and presence of CD57+ cells in the development of inflammatory periapical lesions

The mechanisms that stimulate the proliferation of epithelial cells in inflammatory periapical lesions are not completely understood and the literature suggests that changes in the balance between apoptosis and immunity regulation appear to influence this process.

Association between Cone-Beam Computed Tomography and Histological and Immunohistochemical Features in Periapical Lesions Correlated with Thickened Maxillary Sinus Mucosa

Background and Objectives: Odontogenic sinusitis is a frequently underestimated pathology with fewer symptoms in patients with periapical lesions, periodontal disease, or iatrogenic foreign bodies in the maxillary sinus. The aim of our study was to determine the correlation between maxillary sinusitis and periapical lesions using cone-beam computed tomography (CBCT) imaging and histological and immunohistochemical investigations. Materials and Methods: A total of 1450 initial patients diagnosed with maxillary sinusitis in the Ear-Nose-Throat (ENT) Department, University of Medicine and Pharmacy “Grigore T. Popa” Iasi, Romania, were treated with anti-inflammatory drugs. Of these, 629 still had unresolved symptomatology and were later referred to the Dental Medicine departments for further investigations. Only 50 subjects with periapical lesions in the premolar/molar maxillary area were included in the present study. All the periapical lesions were observed on CBCT and classified using the Periapical Status Index (PSI) and the mean maxillary sinus mucosa thicknesses (MSMT). The enrolled patients underwent surgical procedures with the excision of periapical lesions. The excised samples were submitted to the histological and immunohistochemical investigations. Results: The 50 patients presented periapical lesions of their maxillary teeth in 328 dental units. There was a higher prevalence of periapical lesions in men than in women (chi-square test). We observed a significant difference between the mean MSMT of individuals with periapical lesions compared to those without (p < 0.01). Mean MSMT was 1.23 mm for teeth without periapical lesions and 3.95 mm for teeth with periapical lesions. The histopathological study identified 50% cases with periapical granulomas, 10% cases with periapical granulomas with cystic potential, and 40% cases as periapical cysts. Immunohistochemical stainings showed that CD4+ helper and CD8+ cytotoxic T lymphocytes, along with CD20+ B lymphocytes and CD68+ macrophages, were diffusely distributed in all periapical cysts and in some periapical granulomas, but CD79α+ plasma cells characterized especially periapical granulomas. Conclusions: The current study observed a significant correlation between CBCT maxillary mucosa thickness and type of periapical lesion. Chronic inflammatory lympho-histiocytic infiltrate predominates in periapical lesions, supporting the idea that lesion progression is determined by a humoral-type (CD20+ and CD79α+ B lymphocytes) but also by a cellular-type (CD4+ and CD8+ T lymphocyte population) immune mechanism.

Actinomycosis is not Frequent in the Periapex But is a Persistent Lesion

Periapical actinomycosis caused by a gram-positive anaerobic pathogen characterizes a typical extra-radicular infection. This study determined the frequency and correlated the content of bacteria colonies with the of periapical actinomycosis size. The study comprised a total of 218 periapical lesions (PL) (cysts, granulomas or abscess). The specimens embedded in paraffin were sliced into 4-µm sections and stained with hematoxylin-eosin, Gram, Periodic Acid-Schiff (PAS) and Grocott's stain. The presence of bacterial colonies composed of filamentous structures labeled with the histochemical stains were described as Actinomyces, and for each case, the bacterial colonies were counted and measured. The correlation between the number and size of bacterial colonies and the size of PL was tested using Pearson's adjusted correlation coefficient. From 218 PL, bacterial colonies were identified in 64 biopsies. Seven cases (0.3%) fulfill the criteria for diagnosis of periapical actinomycosis. All of cases were therapy-resistant and did not showed periapical repair after 12 months of follow-up. Periapical surgery or dental extraction was performed. The correlation test indicated no correlation between the number of bacterial colonies and the lesion size (p=0.752, r=-0.148). However, a larger bacterial colony size generally resulted in a larger periapical lesion (P=0.000, r=0.657). The frequency of periapical actinomycosis was low, and this lesion should be included in the differential diagnosis of PL. The size of the Actinomyces colonies seemed to contribute to increase the size of the periapical lesion.

Respiratory Epithelium Lined Cyst of the Maxilla: Differential Diagnosis

Maxillary cysts, including the cysts lined by respiratory epithelium, can present a diagnostic challenge. We report an unusual case of a maxillary cyst on an endodontically treated tooth #16, in which the cavity was totally lined by a respiratory epithelium. The patient, a 35-year-old male, presented with a generalized chronic periodontitis and complained of a pain in the tooth #16 region. A periodontal pocket extending to the root apices with pus coming out from the gingival was found. A combined endodontic periodontal was observed on a panoramic radiography. CBCT-scan revealed a well-circumscribed radiolucent lesion at the apices of the distobuccal root of the 16. A communication with the right maxillary sinus cavity and a maxillary and ethmoidal sinusitis were also observed. The lesion was removed and histological examination revealed a cyst lined exclusively by respiratory epithelium. Ciliated and rare mucous cells were also observed. The diagnosis could evoke a surgical ciliated cyst mimicking the radicular cyst but the patient has no previous history of trauma or surgery in the maxillofacial region. It could also be an unusual radicular cyst in which the stratified squamous epithelium was destroyed by inflammation and replaced by a respiratory epithelium of the maxillary sinus.

Comparative immunoexpression of ICAM-1, TGF-β1 and ki-67 in periapical and residual cysts

Background

This study compared the immunohistochemical expression of ki-67, transforming growth factor beta 1 (TGF-β1) and intercellular adhesion molecule-1 (ICAM-1) in inflammatory periapical cysts and residual cysts.

Material and Methods

The study sample was composed by 25 periapical cysts and 25 residual cysts and immunohistochemical reactions were carried out using antibodies directed against ICAM-1, TGF-β1 and ki-67. Clinical, radiological, gross, histological and immunohistochemical data were tabulated for descriptive and comparative analysis using the SPSS software and differences were considered statistically significant when p<0.05%.

Results

There were no differences between the expression of ICAM-1 (p=0.239) and TGF-β1 (p=0.258) when comparing both groups. Ki-67 labeling index was higher in residual cysts compared to periapical cysts (p=0.017).

Conclusions

Results from the present study suggest that some specific inflammatory stimuli on residual cysts would modulate their mechanisms of etiopathogenesis, growing and repair.

Key words:Periapical cyst, radicular cyst, residual cyst, transforming growth factor beta 1 (TGF-β1), intercellular adhesion molecule 1 (ICAM-1), ki-67.

Correlation between inflammatory infiltrate and epithelial lining in 214 cases of periapical cysts

The aim of this study was to evaluate the prevalence of periapical cysts, identify their clinical and microscopic features and correlate their microscopic features with the inflammatory infiltrate present in the lesion site. A total of 214 cases were collected over a 10-year period. Clinical data, including gender, age, race, symptoms and location of the lesion, were recorded. Two independent examiners with no prior knowledge of the patients' clinical data conducted the microscopic evaluations. Statistical analyses were performed using Fisher's or chi-square tests at a 5% level of significance. The results showed that periapical cysts were more prevalent in white women, with a mean age of 35 years, and in the anterosuperior region. The majority of the lesions were lined by atrophic cystic epithelium, which was associated with moderate inflammatory infiltrate in the cystic capsule (p < 0.01), with a diffuse localization pattern (p = 0.03) and absence of neutrophils (p = 0.01). Our findings suggest that periapical cysts lined by atrophic epithelium are related to the presence of moderate mononuclear inflammatory infiltrate.

Retrospective study of oral and maxillofacial lesions in older Taiwanese patients

OBJECTIVE

The aim was to provide information regarding oral and maxillofacial (OMF) lesions in an older Taiwanese population.

BACKGROUND

The rate of increase of older people in Taiwan is expected to be rapid. OMF lesions are very frequent in the older population, but no studies have been performed on these lesions in Taiwan.

MATERIALS AND METHODS

OMF cases (between 2000 and 2011) in geriatric patients (≥60 years of age) with records of age, sex and histological diagnoses were retrieved from the Oral Pathology Department of our institution. These lesions were classified into four main categories: tumour/tumour-like reactive lesions, cystic/pseudocystic lesions, inflammatory/infective lesions and other miscellaneous lesions.

RESULTS

Six thousand seven hundred and twenty-six lesions were collected from a total of 39 503 OMF lesions in older Taiwanese patients in this study. Most of these lesions were distributed in the inflammatory/infective group, followed by tumour/tumour-like reactive lesions. Squamous cell carcinoma was the most common lesion, and, additionally, there was a high frequency of oral potentially malignant disorders.

CONCLUSIONS

The present study showed trends similar to previous reports from other countries. However, some detailed information was different, perhaps due to the different criteria and different geographic distribution. Worthy of note, our results indicated that screening for oral potentially malignant disorder and oral malignancy in the older population is essential.