[Radiolucency at both lower third molars: the paradental cyst]. / Radiolucentie bij beide derde ondermolaren: een paradentaire cyste.

A 23-year-old man presented with an irritating sensation at the third molar on the left side of the mandible and a bad taste in his mouth. Radiographic and histopathological examination revealed the abnormality was caused by a paradental cyst. The paradental cyst is located distal to a lower third molar and, together with the mandibular buccal bifurcation cyst, belongs to the inflammatory collateral cysts. Treatment consists of enucleation of the cyst and removal of the lower third molar. Recurrences do not occur.

Mandibular Buccal Bifurcation Cyst: Report of Two Cases.

Mandibular buccal bifurcation cyst is a rare inflammatory odontogenic cyst. We reported two cases who complained of painful swelling of extraoral soft tissue. Intraoral examination revealed the partially erupted mandibular first molar. Cone beam computed tomography showed a well-defined cystic lesion surrounding the first molar. Histopathologic images showed the cyst wall was infiltrated by a large number of plasma cells, neutrophils and eosinophils, and lined with a thin layer of non-keratinized stratified squamous epithelium. Finally, the two patients were diagnosed as mandibular buccal bifurcation cyst and treated with cyst enucleation and curettage.

Odontogenic Keratocyst Is Frequently Misdiagnosed for a Lateral Periodontal Cyst in Premolar and Anterior Tooth-Bearing Areas.

INTRODUCTION: Radiolucent lesions with gingival swelling found in the premolar and intercanine region can elicit a different clinical diagnosis than one confirmed by histologic findings. The purpose of the study is to identify and present the frequency of the unexpected microscopic diagnosis of odontogenic keratocyst (OKC) in a location preoperatively favoring a lateral periodontal cyst (LPC) with similar clinical and radiographic appearance. METHODS: A retrospective analysis of biopsies received from 2011 and 2019 was performed, and the number of LPC and OKC cases was assessed. The alignment of clinical and radiographic diagnosis to histologic findings and anatomic location was analyzed, and the number of OKC cases preoperatively misdiagnosed as LPCs was identified. RESULTS: A total of 79,257 biopsies were received. Of those, 184 were diagnosed as LPCs and 742 as OKCs. For all preoperatively diagnosed LPCs, the clinical and histologic diagnosis aligned; however, 182 of 742 OKCs were submitted with a clinical misdiagnosis of LPCs. The location of these lesions with the unanticipated diagnosis overlapped with those for LPCs, specifically the maxillary and mandibular anterior and premolar regions. CONCLUSIONS: Radiolucent lesions with gingival swelling in the premolar and intercanine region are frequently clinically and radiographically misdiagnosed. A biopsy should be considered in all cases to establish the correct pathologic diagnosis and treatment course.

Gingival cyst of the adult, lateral periodontal cyst, and botryoid odontogenic cyst: An updated systematic review.

The aim of the present review was to integrate the available data published on gingival cyst of the adult (GCA), lateral periodontal cyst (LPC), and botryoid odontogenic cyst (BOC) into a comprehensive analysis of their clinical/radiological features. An electronic search was undertaken in July/2017. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm the diagnosis. A total of 146 publications (157 GCAs, 213 LPCs, 96 BOCs) were included. GCA and LPC presented highest prevalence in the sixth/fifth decades; BOC in the sixth/seventh decades. LPCs were larger lesions than GCAs and GCAs appeared at an older age than LPC. There was no statistically significant difference between them for other factors (location, symptoms, recurrence, follow-up time). In comparison with LPC, BOC lesions were larger, appeared more often in mandible and in older subjects, had more often a multilocular appearance, and presented a higher recurrence rate. Recurrence rates: GCA (3.2%), LPC (2.4%), BOC (21.7%). No factor seems to influence the recurrence rate of GCA or LPC. Multilocular radiological appearance seems to affect the recurrence rate of BOCs. Conservative surgical approaches seem to be enough for GCA/LPC. BOC presents a more aggressive behavior than GCA/LPC. Therefore, treatment of this lesion might involve some kind of adjunctive therapy after enucleation.

Botryoid odontogenic cyst. Exploration of proliferative activity, apoptosis and expression of TP53 and BCL2 compared to the histologically identical lateral periodontal and gingival cysts.

The botryoid odontogenic cyst (BOC) is a rare, locally more aggressive variant of the usually indolent lateral periodontal cyst (LPC) and gingival cyst (GC). A recent case of BOC provided an opportunity for an exploratory study on the causes of its more aggressive behavior. The limited objective was to see if the BOC was sufficiently different from the other cysts to warrant an investment in a large study. Sections of neutral buffered formalin fixed, paraffin-embedded tissues from the BOC and archival specimens of four GCs, four LPCs and three odontogenic keratocysts (OKCs) were stained using immunohistochemistry for Ki-67, a marker of proliferating cells, caspase-3, a marker of cells undergoing apoptosis, tumor suppressor p53, and the apoptosis inhibitor BCL2. The mean labeling index (LI) of immunoreactive cyst epithelial cells was computed for each antibody and type of cyst. Compared to the LPCs and GCs, the BOC exhibited a moderately larger Ki-67/caspase-3 LI difference, which indicates that the BOC had a net higher rate of growth. We found a much higher level of LI, therefore likely dysregulation of p53. We also found a much higher LI of BCL2. The LIs of p53 and BCL2 in the BOC were similar to and more than twice that of the OKCs, respectively. Although meaningful statistical analysis was precluded by our use of only one case of BOC and a small number of the other cysts, the high p53 and very high BCL2 labeling indices of the BOC offer a potential explanation for its reportedly more aggressive behavior that clearly is worthy of further investigation.

A Rare Case of Gingival Cyst in a Child.

Gingival cysts, which are more frequently reported as gingival cysts of adults (GCA), are soft tissue cystic lesions of odontogenic origin that are infrequently seen, especially in children. These lesions usually appear as localized firm elevations on the facial gingiva in the anterior segment of the mandible. The purpose of this paper is to present a rare case of a gingival cyst discovered on the palatal aspect of the posterior maxilla in a four-year-old child. The lesion was treated with excisional biopsy.

Odontogenic Cysts and Neoplasms.

This article reviews a myriad of common and uncommon odontogenic cysts and tumors. The clinical presentation, gross and microscopic features, differential diagnosis, prognosis, and diagnostic pitfalls are addressed for inflammatory cysts (periapical cyst, mandibular infected buccal cyst/paradental cyst), developmental cysts (dentigerous, lateral periodontal, glandular odontogenic, orthokeratinized odontogenic cyst), benign tumors (keratocystic odontogenic tumor, ameloblastoma, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, ameloblastic fibroma and fibroodontoma, odontoma, squamous odontogenic tumor, calcifying cystic odontogenic tumor, primordial odontogenic tumor, central odontogenic fibroma, and odontogenic myxomas), and malignant tumors (clear cell odontogenic carcinoma, ameloblastic carcinoma, ameloblastic fibrosarcoma).

Managing a Lateral Periodontal Cyst With Bone Graft: A Computed Tomography Assessment 18 Months Postoperatively.

The lateral periodontal cyst is a rare benign lesion that is generally asymptomatic and commonly discovered by routine intraoral radiography. Reports on proper management of this lesion are readily available. However, the literature is sparse regarding the long-term outcomes following surgery. A traditional radiographic technique does not provide an adequate image of the healing, and a patient may resist the prospect of a reentry procedure. The current report is the first to utilize a cone-beam computed tomography scan to evaluate the healing potential of a freeze-dried bone allograft approximately 18 months postoperatively.

Inflammatory collateral cyst associated with a palatoradicular groove: report of a case and discussion of nomenclature.

The aims of this article are to present a case demonstrating the connection between palatoradicular grooves and inflammatory collateral cysts and to discuss the related nomenclature. Radiographs in a 21-year-old man revealed a radiolucent, unilocular, well-defined area near the vital maxillary right lateral incisor and canine. Palatal swelling was present, and a 6-mm-deep periodontal pocket was found at the palatal surface of the right lateral incisor. The differential diagnoses were keratocystic odontogenic tumor, developmental lateral periodontal cyst, and inflammatory lateral periodontal cyst. The area was explored surgically, and the lesion was excised. Surgical exploration revealed a palatoradicular groove, which was scaled and planed with the aid of manual curettes with the intention of creating a flat surface to promote insertion of the periodontal fibers. Histopathologic analysis revealed that the lesion was an inflammatory cyst. The presence of a palatoradicular groove can put the periodontium at risk because a resulting lack of fiber insertion makes oral hygiene difficult. This established inflammatory process can initiate development of an inflammatory collateral cyst that may be misdiagnosed, hindering successful management. In this case, bone grafting and placement of a resorbable membrane were used to promote bone formation and subsequent sealing of the periodontal space.

Paradental cyst is an inclusion cyst of the junctional/sulcular epithelium of the gingiva: histopathologic and immunohistochemical confirmation for its pathogenesis.

OBJECTIVE: The aim of this study was to characterize the histologic and immunohistochemical profiles of paradental cyst-lining epithelia to clarify its histopathogenesis. STUDY DESIGN: Ten surgical specimens of paradental cysts were examined for clinical profiles and to determine the histopathologic characteristics of the lining epithelia. Immunohistochemical profiles for keratin (K) subtypes, as well as for perlecan, UEA-I lectin binding, and proliferating cell nuclear antigen (PCNA), were determined and compared. RESULTS: The paradental cyst was clinically characterized by its occurrence in young adults (mean age, 36.8 years; male, 42.8, female 27.8). Eight of the 10 cases arose in the retromolar area. The cyst wall was basically granulation tissue that was attached to the periodontal ligament space. Thin irregular anastomosing epithelial cords lined the cyst walls of immature granulation tissue with vascular dilation and hemorrhage. The intercellular space of the lining epithelia was widened with inflammatory cell infiltrates. Immunohistochemically, the lining was positive for K13, K14, K17, K19, UEA-I binding, and perlecan, suggesting its junctional/sulcular epithelial character. CONCLUSION: The results showed that the paradental cyst was lined by epithelial cells with characteristics of the junctional/sulcular epithelium. The cyst can thus be considered as a kind of inclusion cyst arising in the periodontal pocket, most frequently of the mandibular third molars of young adults.

Lateral periodontal cyst.

The lateral periodontal cyst (LPC) is a harmless developmental aberration derived from odontogenic epithelia lying between the roots of vital teeth. The exact histogenesis of LPC is a matter of debate but therapy is usually only required to maintain stable periodontal conditions and in case of evidence for growth of the cyst. We report on a case of LPC where successful surgical therapy had initialized osseous restoration. We further discuss the value of histological findings to substantiate a clinical and radiological diagnosis.

A clinicoradiographic and pathological study of pericoronal follicles associated to mandibular third molars.

BACKGROUND: Third molar surgery is considered the most frequently performed procedure in oral surgery. Although there are some indications for the removal of this tooth, such as the possibility of cystic degeneration or a tumor of the adjacent pericoronal follicle, there is no consensus in the literature about their prophylactic removal. OBJECTIVES: The aims of this study were to investigate the pathological alterations related to mandibular third molar dental follicles and to perform a narrative literature review. METHODS: A prospective clinical, radiographic, and histopathologic study was conducted with pericoronal follicles of third molars. After histopathologic evaluation and establishment of diagnosis, 2 groups were defined: G1 (pericoronal tissues with pathological alterations based on histopathologic analysis) and G2 (pericoronal tissues without pathological alterations based on histopathologic analysis). In addition, a systematic review of the literature was performed. RESULTS: One hundred thirteen specimens were analyzed. G1 was the most prevalent (P = 0.0004). Lesions were found in patients between 20 and 25 years of age (P < 0.004). The most prevalent histological diagnosis was the paradental cyst (47.7%; P < 0.0001). The narrative literature review showed that the majority of cases were mainly dentigerous cysts (P < 0.05). CONCLUSIONS: The mandibular third molars in young adults showed a direct relationship with age and a statistical propensity for the development of these cystic alterations, notably paradental cysts.

Juvenile paradental cyst: presentation of a rare case involving second molar.

The aim of this article was to describe a rare case of paradental cyst of the permanent mandibular second molar. A 14-year-old girl was referred to Oral Surgery Department, Dental Clinic, IRCSS Fondazione Ca' Granda, University of Milan, Italy, for the evaluation of the deep probing located on the buccal aspect of her erupted mandibular left second molar. Clinical signs of inflammation were absent and the mucosa around the second molar appeared clinically normal. Pulp tests for the second molar were positive. The evaluation of the panoramic radiograph did not revealed radiolucency. The Cone-beam tomography showed a well-defined semilunar-shaped radiolucency demarcated by a fine radiopaque line. The cyst was enucleated. The histopathologic analisys revealed the presence of hyperplastic, non-keratinized squamous epithelium with heavy, dense inflammatory cell infiltrate in the epitelium and connective tissue wall. This analysis associated with macroscopic, clinical and radiografic examination confirmed the diagnosis of paradental cyst. A clinic-pathologic correlation, incorporating the surgical, radiographic and histologic findings, is required to obtain the final diagnosis of paradental cyst. Today, the treatment of choice is simple enucleation and thorough curettage of the cyst without extraction of the involved tooth, but if CT demonstrates erosions in the buccal or lingual cortices, marsupialization should be the treatment of choice.

Bilateral lateral periodontal cyst.

The bilateral lateral periodontal cyst is a rare nasological entity, which despite clinical and radiological presentation is being diagnosed by histological characteristics. It is asymptomatic in nature and is observed in routine radiography. The aim and objective of this article is to present a rare case of bilateral lateral periodontal cyst in a 14-year-old child. The clinical and radiographical findings, along with its management have been discussed. Enucleation of bilateral cyst without extraction of the adjacent tooth was performed. Lesion samples were sent for histopathological analysis. The histopathological analysis revealed a thin, non keratinised stratified squamous epithelium resembling reduced enamel epithelium. Epithelial plaques were also seen. A clinicopathological correlation incorporating the surgical, radiographical and gold standard histopathological findings was obtained to suggest the final diagnosis of the bilateral lateral periodontal cyst.

Analysis of the frequency and nature of hyaline ring granulomas in inflammatory odontogenic cysts.

AIM: To determine the prevalence of hyaline ring granulomas (HRGs) in a large case series of inflammatory odontogenic cysts, and to investigate the nature of these structures. METHODOLOGY: All records from the patients diagnosed with inflammatory odontogenic cysts between January 1970 and April 2009 were reviewed. Histologic sections were evaluated by light microscopy and cases with HRGs for which sufficient biological material was available were submitted to histochemical analysis (Masson's trichrome) and immunohistochemistry (CD34, CD68 and collagen IV). RESULTS: Twenty-two (3.3%) of the 661 cases of inflammatory odontogenic cysts diagnosed during the study period presented HRGs. The relative frequency of HRGs was higher amongst residual radicular cysts (6.1%), followed by paradental cysts (5.6%) and radicular cysts (3.0%). HRGs appeared as roughly circular homogeneous/fibrillar masses in 14 (63.6%) cases and as round structures enclosing amorphous material in 3 (13.6%) cases. Most (77.8%) roughly circular homogeneous/fibrillar masses were positive for collagen, whereas all (100.0%) round structures enclosing amorphous material were negative for this protein. Immunohistochemistry showed that most mononucleated cells and all multinucleated giant cells were positive for CD68, but negative for CD34, in all cases. In addition, collagen IV immunostaining was negative in amorphous structures and weakly positive in homogeneous/fibrillar masses. CONCLUSIONS: The present results suggest a very low frequency of HRGs in inflammatory odontogenic cysts and support the hypothesis that these structures arise from the implantation of foreign material, most likely food particles of plant or vegetable origin. The diverse microscopic features of HRG possibly represent different developmental stages of this structure.

Lateral and median cysts of the neck.

THE AIM OF THE STUDY: was to present clinical picture, indications for surgery, immediate and remote results of surgical treatment for lateral and median cysts of the neck. MATERIAL AND METHODS: A total of 17247 patients were operated between 1 January 1990 and 31 December 2011 for neck tumors. RESULTS: Neck cysts were diagnosed in 34 (0.2%) patients, including lateral in 12 (35.3%) and median in 22 (64.7%). Lateral cyst once descended to the mediastinal. Nodular goitres were diagnosed in 17 (50%) of them--with the lateral cysts 4x and median cysts 13x. Guided fine-needle aspiration biopsy of the cyst-like lesions revealed the presence of protein masses in all patients. The lesions were found to have inflammatory character in 6 patients (17.6%) regarding median cysts (5x) or lateral cyst (1x). Out of them, 3 patients developed purulent inflammatory process. All patients were operated. The operation consisted of radical resection of the cyst only or plus partial resection of both thyroid lobes and total resection of pyramidal lobe if concomitant goitre was found. Two patients required one-stage resection of the enlarged lymph nodes in the neck. Suspected focus of thyroid papillary cancer was found by intra-operative examination in neck median cyst wall in one patient. However, paraffin tests did not confirm the suspicion. Another patient was found by histopathological examination to have active tuberculotic process within both lateral cyst and lymph nodes. The patient received intensive antituberculotic treatment postoperatively. CONCLUSIONS: 1. Median cysts of the neck are more often accompanied by thyroid tumor-like goitres than lateral cysts. 2. Radical resection of the cysts in operative treatment results in good long term patient condition and prevent in recurrence of the illness.

Ectopic production of hair keratin constitutes Rushton's hyaline bodies in association with hematogenous deposits.

A Rushton's hyaline body (HB) is a concretion occasionally found in odontogenic cysts. Unspecified substances produced by the lining epithelium or derived from blood components have been suggested as possible causes of HB formation, but the origin of HBs is still elusive. This study aimed to clarify the origin of HBs. Ten specimens with HBs were obtained from 400 odontogenic cysts. HBs were stained by orcein and Congo red. Immunohistochemical examination revealed that HBs were positive for hair keratin and keratin 17. Hair keratin was concentrated in HBs, and cells with hair keratin expression were hardly seen, while cells with keratin 17 expression were observed near HBs. HBs were also positive for hemoglobin alpha chain. The presence of hair keratin in HBs was confirmed by Western blot analysis. The present study suggests that HBs are formed as a consequence of two independent events: unusual alteration of epithelial differentiation so as to provide hair keratin, and hemorrhage so as to provide erythrocytic substances. Although the ectopic production of hair keratin appears more essential, our results reconcile the long-standing debate between two theories, the keratin theory versus the hematogenous theory, concluding that both substances are required for the genesis of HBs, and also suggesting that they might be novel non-pathological amyloidogenic proteins.