Experimental dentigerous cysts and enamel hypoplasia: their possible significance in explaining the pathogenesis of human dentigerous cysts

Conservative Management of Dentigerous Cysts Associated With Mixed Dentition: A Retrospective Cohort Study

Objectives The pediatric dentigerous cysts might vary by region and population group. Large cystic lesions are typically treated with marsupialization before enucleation in order to decompress the lesion and reduce its volume; however, in pediatric cystic lesions, conservative marsupialization and decompression can be used to manage the condition without additional enucleation. The current study's objectives were to present a case series of pediatric dentigerous cysts and discuss the conservative management of these cystic lesions associated with mixed dentition. Methods A retrospective cohort analysis of patients diagnosed with cystic lesions between 2016 and 2023 was identified. Data on clinical, radiological, pathological, and odontogenic causes were collected. The marsupialization approach was performed in all cases. Patient demographic information was also examined, and a literature review was carried out to identify comparable cases. Results Sixteen young patients were diagnosed with dentigerous cysts, and this was confirmed by clinical, radiological, and pathological examinations. Females comprised 56.2% of the cases, with the right side predominating (62.5%). Deciduous teeth related to the lesion could be extracted normally in all cases. All associated permanent teeth erupted rapidly after the intervention. Conclusion The marsupialization technique used in the current cases of dentigerous cysts associated with mixed dentition was highly successful, and all permanent impacted teeth erupted without any cystic recurrence.

Bilateral Nonsyndromic Cystic Lesions Involving Impacted Teeth: Nomenclature and Diagnostic Protocol

Aim

To present a brief overview of etiopathogenesis, nomenclature, and treatment modality for a case of nonsyndromic bilateral cysts in the mandible.

Background

Odontogenic cysts, though comprise a distinct group of lesions have on and off posed challenges in etiopathogenesis and nomenclature. The prima facia role of development/inflammation in the buildup of fluid between the reduced enamel epithelium attached at the cementoenamel junction and the enamel in the pathogenesis of dentigerous cysts has long been discussed. Along with this, the spread of inflammatory exudate from an overlying primary tooth could also be the source of an inflammatory dentigerous cyst.

Case description

Bilateral swellings in a 12-year-old patient presented with a chief complaint of pain in the lower jaw for 4 months. The radiographic picture exhibited unilocular, well-circumscribed radiolucent areas extending from 34 to 37 on the left side and from 44 to 47 on the right side of the mandible and involving retained mandibular second premolars on both sides.

Conclusion

Mere expansion of a follicle due to inflammation from an overlying infected/necrosed/treated primary tooth in which the reduced enamel epithelium does not appear to be attached at the cementoenamel junction should be aptly referred to as an “inflammatory follicular cyst”.

Clinical significance

The present article attempts to illuminate the notable differences between dentigerous cysts and inflammatory follicular cysts of jaws which requires an adequate distinction in pediatric cases for diagnostic and management considerations.

How to cite this article

Sethi A, Shetty DC, Tandon A, et al. Bilateral Nonsyndromic Cystic Lesions Involving Impacted Teeth: Nomenclature and Diagnostic Protocol. Int J Clin Pediatr Dent 2020;13(4):429–432.

Longstanding dental pathology in Neandertals from El Sidrón (Asturias, Spain) with a probable familial basis

Two Neandertal specimens from El Sidrón, northern Spain, show evidence of retained left mandibular deciduous canines. These individuals share the same mitochondrial (mtDNA) haplotype, indicating they are maternally related and suggesting a potential heritable basis for these dental anomalies. Radiographs and medical CT scans provide evidence of further, more extensive dental pathology in one of these specimens. An anomalous deciduous canine crown morphology that developed before birth subsequently suffered a fracture of the crown exposing the pulp sometime after eruption into functional occlusion. This led to death of the tooth, periapical granuloma formation and arrested deciduous canine root growth at an estimated age of 2.5 years. At some point the underlying permanent canine tooth became horizontally displaced and came to lie low in the trabecular bone of the mandibular corpus. A dentigerous cyst then developed around the crown. Anterior growth displacement of the mandible continued around the stationary permanent canine, leaving it posteriorly positioned in the mandibular corpus by the end of the growth period beneath the third permanent molar roots, which, in turn, suggests a largely horizontal growth vector. Subsequent longstanding repeated infections of the expanding cyst cavity are evidenced by bouts of bone deposition and resorption of the boundary walls of the cyst cavity. This resulted in the establishment of two permanent bony drainage sinuses, one through the buccal plate of the alveolar bone anteriorly, immediately beneath the infected deciduous canine root, and the other through the buccal plate anterior to the mesial root of the first permanent molar. It is probable that this complicated temporal sequence of dental pathologies had an initial heritable trigger that progressed in an unusually complex way in one of these individuals. During life, this individual may have been largely unaware of this ongoing pathology.

Dentigerous Cyst of Inflammatory Origin

A dentigerous cyst encloses a crown of an unerupted tooth by its follicle and is attached to the neck of the tooth. They may be of developmental or inflammatory origin. Dentigerous cyst of inflammatory origin occurs in immature tooth as a result of inflammation from preceding non-vital deciduous tooth or from other source spreading to involve the tooth follicle. These are diagnosed in the first and early part of second decade either on routine radiographic examination or when patient complains of swelling and pain. They generally involve mandibular premolars.

This article presents a case report of an 11-year-old male patient with a dentigerous cyst of inflammatory origin in the left mandibular premolar region with radiographic feature of a large unilocular radiolucency involving unerupted second premolar. The treatment rendered in this patient comprised of surgical enucleation of cyst under local anesthesia along with extraction of mandibular first and second primary molars.

Trauma-induced dentigerous cyst involving an inverted impacted mesiodens: case report

There have been only a small number of studies on the association of dentigerous cysts with supernumerary teeth. The purpose of this article was to report the case of a dentigerous cyst associated with an impacted inverted mesiodens that developed secondary to trauma to its predecessor, a non-vital permanent maxillary central incisor. As a consequence of trauma, the central incisor's root development was prematurely arrested and the open apex lay close to the follicle of the underlying inverted mesiodens. The negligent attitude of both the child and parent in seeking dental treatment was a contributing factor. The case was further complicated by impaction of the adjacent permanent central incisor due to the presence of another unerupted but normally oriented mesiodens. Occlusal and Intraoral periapical radiographs revealed a well-defined radiolucent area surrounding the inverted mesiodens. Microscopic examination revealed a cystic cavity that was lined by 2-3 cell thick non-keratinized stratified squamous epithelium resembling reduced enamel epithelium. Dentigerous cysts associated with impacted permanent teeth are not uncommon but the cysts which are induced by trauma are uncommon. Development of trauma-induced dentigerous cyst around an inverted impacted mesiodens associated with the periapical area of a traumatized, non-vital, immature permanent central incisor is a rare occurrence.

Radiographic examination of dentigerous cysts in the transitional dentition

OBJECTIVES

To examine radiographically the relationship between the deciduous tooth and dentigerous cyst of the permanent successor during the transitional dentition.

METHODS

From a retrospective review of all patients who visited our institution from April 1988 to August 2001, 70 patients under 16 years of age who had histologically confirmed dentigerous cysts that had developed from the central incisor to the second premolar were identified. These 70 patients were investigated using panoramic and periapical radiographs.

RESULTS

In most cases (54 cases; 77.1%) the cyst was in the premolar region. Of the 54 premolars with dentigerous cysts, the overlying deciduous tooth had already been lost in 7 cases. Of the 47 remaining premolars with associated deciduous tooth, 35 (74.5%) had bone resorption of the periapical or bifurcation region, or irregular resorption of the associated deciduous tooth. Of the remaining 12 deciduous teeth with no periapical lesions, 9 had been treated with root canal therapy. Thus, 44 of these 47 cases (93.6%) had the possibility of inflammation at the deciduous tooth associated with the dentigerous cyst. Evidence from one case in the present study suggesting the process by which cyst development occurs is also given.

CONCLUSION

Inflammatory change at the apex of the deciduous tooth may bring on a dentigerous cyst of the permanent successor.

Pathologically significant pericoronal lesions in adults: Histopathologic evaluation

PURPOSE

Oral and maxillofacial surgeons devote a large portion of their practice to the removal of impacted teeth. Many of these teeth have associated soft tissue that is submitted along with or without the tooth for histopathologic examination. This study reports the histopathologic diagnoses of a large series of pericoronal lesions in adults submitted to an oral and maxillofacial pathology biopsy service.

MATERIALS AND METHODS

Two thousand six hundred forty-six pericoronal lesions received during a 6-year period were reviewed for location, age, and histopathologic diagnosis.

RESULTS

Retrospective evaluation showed that 67.1% of all submissions were nonpathologic follicular tissue. Pathologically significant lesions were diagnosed in 32.9% of cases. Among these lesions were 673 dentigerous cysts (28.4%), 79 dentigerous cysts with mucous cell prosoplasia, 71 odontogenic keratocysts (2.68%), 19 odontomas (0.7%), 13 ameloblastomas (0.5%), 6 carcinomas (0.23%), 6 calcifying odontogenic cysts (0.23%), 4 calcifying epithelial odontogenic tumors, and 1 odontogenic myxoma (0.04%). When stratified by age, the data showed pathologically significant lesions and age are related (chi(2), P <.0001).

CONCLUSIONS

Because of selection bias inherent in a study of this nature, population generalizations cannot be made. However, this study serves to show that the potential for the development of significant, even life-threatening, disease associated with impacted teeth is real and should be a factor in the decision-making process when oral surgeons and others are confronted with the dilemma of managing an impacted tooth.

A contribution to the diagnosis of the small dentigerous cyst or the paradental cyst

The aim of this study was to verify the relationship between the radiographically measured width of the pericoronal space (PS) and the microscopic features of the follicle in order to contribute to the diagnosis of small dentigerous cysts and paradental cysts. One hundred and thirty unerupted teeth (UT) and thirty-five partially erupted teeth (PET) were radiographed and extracted. The radiographic analysis consisted of measuring the width of the PS. The results of the radiographic analysis were compared with those of the histopathologic examination of the dental follicle. The width of the PS ranged from 0.1 to 5.6 mm. The most frequently observed lining of the follicles was a reduced enamel epithelium (REE) (68.4%) in UT and a hyperplastic stratified squamous epithelium (HSSE) (68.5%) in PET. Inflammation was present in 36.1% of the UT and in 82.8% of the PET. There was a statistically significant association between the presence of stratified squamous epithelium (SSE) and PS enlargement for UT (p < 0.05). There was a tendency of association between inflammation and PS enlargements in PET and, possibly, in UT, despite the absence of statistical significance. Surgically, we did not detect bone cavitation or luminal cystic contents in pericoronal spaces smaller than 5.6 mm. We suggest that the first radiographic diagnosis for a PS enlargement, in most of the routine clinical cases, should be of "inflammation of the follicle". The hypothesis of "dentigerous cyst" or "paradental cyst" is suggested as a second diagnosis. The final differential diagnosis between a small dentigerous or a paradental cyst and a pericoronal follicle depends on clinical and/or surgical findings, such as the presence of bone cavitation and cystic content.

Experimental odontogenic cysts induced by in vitro 4-nitroquinoline 1-oxide (4NQO) treatment of F344 rat incisor tooth germs

This study was designed to establish an experimental animal model for elucidating the early stages of odontogenic cysts and tumors. It involves the in vitro treatment of tooth germs with 4-nitroquinoline 1-oxide (4NQO) at the early bell stage and their subsequent transplantation into the kidney subcapsular space. While all tooth germ transplants of the control group not exposed to the carcinogen showed continued tooth development with no pathological lesions, 21 of 23 4NQO-treated tooth germs developed into similar appearing keratinized cysts with or without associated tooth structures. The remaining two transplants failed to develop cysts and formed only a tooth. The present experimental procedure was effective in inducing keratinized cystic lesions that exhibit some similarities to human odontogenic keratocysts or primordial cysts.

Dentigerous cysts of inflammatory origin. A clinicopathologic study

The exact histogenesis of dentigerous cysts remains unknown, but most authors favor a developmental origin from the tooth follicle. The aim of this article is to report a series of 15 dentigerous cysts that we believe to be of inflammatory origin. These inflammatory dentigerous cysts occurred in the first and early part of the second decades of life. Males were affected more frequently, and there did not appear to be any racial predilection. All of the cases involved permanent teeth: premolars in nine cases, canines in four cases, and second molars in two cases. The mandible was affected twice as frequently as the maxilla. In 13 cases, nonvital grossly carious or heavily restored deciduous teeth were associated with the cysts. Some of these teeth had been extracted before the cysts were diagnosed. In the remaining two cases, both of which involved the second permanent molars, there were no nonvital deciduous teeth, however both had concomitant proliferative periostitis. All of the cysts were moderately or intensely inflamed and were lined predominantly or entirely by nonkeratinized stratified squamous epithelium that in some cases was markedly hyperplastic and exhibited anastomosing rete ridges mimicking radicular cysts. In the majority of cases, parts of the cysts were lined with a 2 to 3 cell layer thick cuboidal epithelium that we believe was derived from reduced enamel epithelium. Rests of odontogenic epithelium frequently were evident in the cyst walls. We suggest that these cysts arose as a result of periapical inflammation from any source but usually from a nonvital deciduous tooth and spreading to involve the follicles of the unerupted permanent successors. The inflammatory exudate causes separation of the reduced enamel epithelium from the enamel with resultant cyst formation. This study proposes the existence of two types of dentigerous cysts: one developmental and the other inflammatory in nature.

The small dentigerous cyst. A diagnostic dilemma

The dentigerous (follicular) cyst is recognized as one of the most common lesions of the jaws. Clinical, radiographic, histologic, and prognostic characteristics are well established for medium to large pericoronal cysts that are lined by nonkeratinized stratified squamous epithelium. However, it can be difficult, if not impossible, to distinguish between a small dentigerous cyst and a large dental follicle despite the availability of both radiographic and histologic information. Epidemiologic data derived from a comparative study of 1662 dentigerous cysts and 824 dental follicles showed considerable overlap in age distribution and site predilection and were therefore of minimal use in reaching a final diagnosis. At present, it appears that identifying a cystic cavity at the time of surgery may be the only reliable way to arrive at a definitive diagnosis when radiographic and histologic features are insufficient to distinguish between a small dentigerous cyst and a large dental follicle.

Developmental odontogenic cysts. An update

This review paper reports recent advances in the subject of developmental odontogenic cysts, essentially those of the past decade, starting with reference to the new WHO classification (1). On keratocysts, the latest reported recurrence rates are assessed as are their mode of growth, immunocytochemistry, immunology, genetic studies, and work on specific keratocyst antigens. There is a critical account of the group of lesions which includes the gingival cyst of adults, lateral periodontal cyst, botryoid odontogenic cyst and glandular odontogenic cyst, and their possible relationship to one another. On dentigerous cysts, reference is made to the relationship between them and deciduous teeth, as well as to their immunocytochemistry and immunology. Recent work on the unicystic ameloblastomas, their classification and prognosis, is assessed, as is the calcifying odontogenic cyst and its relationship with solid odontogenic tumours.

Odontogenic cyst induction by periapical infection in rats

The purpose of this study was to test the hypothesis that odontogenic cysts can be induced by periapical infection. Pulp extirpation and reaming beyond the root apices were performed in 53 lower first molars in 27 Sprague-Dawley rats. The cavities were left open to allow continuous contamination by oral bacteria. Animals were killed at 6 and more than 8 months after operation. Odontogenic cysts were found in association with 8/53 teeth in 6 animals. Histologically, cysts were observed around the lower incisors below the first molars. The cyst wall consisted of fibrous connective tissue with inflammation and was lined with keratinized squamous epithelium. The cyst cavity contained a mass of keratin and necrotic debris. These results support the hypothesis that inflammatory stimulation from the apices can cause cystic changes in the enamel epithelium of underlying teeth.

Ameloblastic fibroma in an infant

A case of ameloblastic fibroma associated with a hypoplastic lesion in an unerupted deciduous central incisor is presented. Whether this case provides new evidence concerning the time and source of origin of the ameloblastic fibroma is open to debate, but the possible implications may be worthy of further study.

Epithelial jaw cysts: 10 years of the WHO classification

Numerous papers on epithelial jaw cysts have appeared in the decade since the publication in 1971 of the WHO histological classification of odontogenic tumours, jaw cysts, and allied lesions. Despite clarification of certain cyst varieties no major revisions are necessary. The following minor modifications are proposed. In the developmental odontogenic group, the terms keratocyst and follicular are preferred to primordial and dentigerous. The alveolar cyst of infants is categorised separately from the gingival cyst of adults. The developmental lateral periodontal cyst is included as a distinctive new type. In the non-odontogenic group the globulomaxillary is deleted as a unique entity, whereas the midpalatal cyst of infants is a new inclusion. To the inflammatory category are added the inflammatory follicular and inflammatory lateral periodontal varieties.