the field of dentistry frequently encounters developmental odontogenic cysts, with the lateral periodontal cyst (lpc) standing out due to its relatively uncommon presentation.
often initially identified as a radiographic anomaly, this cyst typically appears as a well-defined, circular, or teardrop-shaped radiolucent area. its strategic placement, often adjacent to the roots of healthy teeth, can lead to initial misdiagnoses, frequently mistaken for lesions originating from the tooth's pulp or nerve pathways.
definitive confirmation of an lpc relies heavily on meticulous histopathological examination.
this paper aims to illuminate a typical instance of a lateral periodontal cyst discovered in the anterior mandibular region and to offer a comprehensive review of existing literature, detailing the clinical, radiological, and histopathological hallmarks of these unique cysts.
the importance of accurate diagnosis and appropriate management cannot be overstated, particularly when considering the potential for confusion with other oral pathologies.
case presentation: a patient's experience
a 50-year-old female patient sought consultation due to a noticeable, yet painless, swelling on her gums, situated between her left mandibular lateral incisor and canine.
preliminary radiographic assessments revealed a distinct, well-circumscribed radiolucency measuring approximately 0.8 cm in diameter. critically, the teeth adjacent to this lesion exhibited healthy, vital pulps, ruling out endodontic involvement as the primary cause.
following these findings, a surgical intervention was planned.
the treatment involved the complete enucleation of the cyst. intraoperative observation confirmed a singular lesion, with no apparent connection or communication to the surrounding oral environment. subsequent histological analysis confirmed the nature of the lesion as a "lateral periodontal cyst of developmental origin." a thorough follow-up over a 24-month period revealed no signs of recurrence or any post-operative complications.
this case underscores a crucial diagnostic consideration: the lateral periodontal cyst must be included in the differential diagnosis when a radiolucent lesion is identified in close proximity to the roots of vital teeth.
the primary treatment approach involves surgical excision, followed by detailed histological evaluation to solidify the diagnosis. recurrence rates for this condition are generally low.
odontogenic cysts: classification and characteristics
according to the world health organization (who) classification system, odontogenic cysts are categorized based on their epithelial lining into two primary groups: inflammatory and developmental.
within the developmental category, lateral periodontal cysts (lpcs) have been recognized as a distinct entity.
defining the lateral periodontal cyst
lpcs are characterized as non-keratinized, non-inflammatory developmental cysts that arise adjacent to, or laterally from, the root of a vital tooth.
while their most common site of occurrence is the mandibular premolar region, instances have been documented in various other locations within the jawbones.
prevalence and clinical presentation
lpcs represent one of the less frequently encountered types among developmental odontogenic cysts.
a significant characteristic is their typically asymptomatic nature; patients rarely report pain or other noticeable symptoms, leading to their frequent discovery during routine dental examinations and radiographic screenings.
radiographic imaging of an lpc usually displays a well-defined, round or oval radiolucent area, often bordered by a sclerotic (dense bone) margin. the majority of these lesions measure less than 1 cm in diameter.
histological features
histologically, the lateral periodontal cyst is distinguished by its epithelial lining.
this lining is typically thin, composed of one to five layers of non-keratinized epithelium, closely resembling the reduced enamel epithelium. focal thickenings or plaques within this epithelial layer are common, often containing clear, glycogen-rich cells.
the connective tissue immediately beneath the epithelium may exhibit a zone of hyalinization, a unique histological finding.
the distinct characteristics of the lpc necessitate careful differentiation from lesions of endodontic and periodontal origins, as well as other related cysts within the odontogenic group.
understanding these nuances is vital for accurate diagnosis and treatment planning.
pathogenesis and differential diagnosis
the origins and developmental pathways of the lateral periodontal cyst, the gingival cyst of the adult, the botryoid odontogenic cyst, and the glandular odontogenic cyst are thought to be interconnected.
some researchers propose a shared histogenesis between the gingival cyst of the adult and the lpc, suggesting that these lesions can manifest both outside (extra-osseous) and inside (intra-osseous) the jawbone.
this article presents a classic case of an lpc situated in the anterior mandible and provides a concise review of its clinical, radiological, and histopathological aspects, drawing from existing scientific literature.
case details revisited
the 50-year-old patient, identified as black, was referred to the são paulo state university (unesp), são josé dos campos dental school, department of biosciences and oral diagnosis, in são josé dos campos, são paulo, brazil.
her chief complaint was the mobility of her left mandibular lateral incisor. she reported a history of using her teeth to manipulate objects in this area, with the onset of the observed change occurring approximately six months prior to her visit. clinical examination revealed slight horizontal mobility of the affected tooth.
palpation of the vestibular surface of the alveolar process in the region of teeth 32 (left mandibular lateral incisor) and 33 (left mandibular canine) elicited no discomfort or pain. vitality tests confirmed that the pulps of both teeth 32 and 33 were alive and responsive.
radiographic findings and diagnosis
a periapical radiograph of the area was obtained.
the radiographic examination clearly showed a well-circumscribed, unilocular, radiolucent lesion measuring approximately 0.8 cm. this lesion was specifically located between the roots of the two adjacent vital teeth, 32 and 33. based on these combined clinical and radiographic findings, a preliminary clinical diagnosis of lateral periodontal cyst was established.
surgical management and histological confirmation
under local anesthesia, a full-thickness mucoperiosteal flap was carefully elevated to expose the lesion.
the cyst capsule was gently separated from the surrounding bone tissue. a complete enucleation of the cystic lesion was performed using a surgical curette. the excised cyst was then submitted for detailed histological examination.
histological sections revealed a solitary cystic cavity lined by epithelium of varying thickness.
in some areas, the lining consisted of one or two layers of cuboidal cells, while in other regions, it showed focal thickenings or clusters of more voluminous cells. notably, several of these cells contained periodic acid-schiff (pas) positive material, indicating the presence of glycogen.
the cyst capsule was composed of fibrous connective tissue, with some areas of bleeding and an absence of inflammatory cell infiltration. these histological findings definitively supported the diagnosis of a lateral periodontal cyst of developmental origin.
post-operative follow-up
the patient underwent a follow-up examination 24 months after the surgical procedure.
radiographic imaging at this time demonstrated complete and uneventful healing of the surgical site, with evidence of spontaneous bone regeneration in the periapical area.
lateral periodontal cyst: a comprehensive overview
the lateral periodontal cyst (lpc) is classified as a developmental odontogenic cyst with an infrequent occurrence, often found in association with vital teeth.
it accounts for approximately 0.5% to 1.5% of all odontogenic cysts.
epidemiology and demographics
literature reviews indicate that lpcs tend to affect adults, predominantly between the fifth and seventh decades of life, with an average age of onset around 52 years.
studies have not shown a significant predilection for any particular race or gender.
anatomical distribution
the most commonly reported location for lpcs is the mandibular premolar region. other frequent sites include the anterior region of the maxilla, followed by the mandibular anterior region.
less common locations have also been documented.
clinical and radiographic presentation
as previously mentioned, lpcs are typically asymptomatic. the associated teeth remain vital unless the cyst becomes secondarily infected. consequently, lpcs are often discovered incidentally during routine radiographic examinations.
the radiographic appearance is usually that of a well-defined, unilocular radiolucency, characteristically located lateral to the root of a vital tooth.
etiopathogenic hypotheses
several theories attempt to explain the pathogenesis of lpcs:
- reduced enamel epithelium: this hypothesis suggests that the cyst lining originates from the reduced enamel epithelium, a remnant from tooth development.
support for this theory comes from immunohistochemical studies demonstrating the presence of proliferating cell nuclear antigen (pcna) in the epithelial lining, a marker of cell proliferation.
- remnants of dental lamina: another theory posits that lpcs arise from remnants of the dental lamina, a structure crucial during early tooth development.
the presence of glycogen-rich clear cells, often seen in lpcs, is also a characteristic feature of the dental lamina.
- epithelial rests of malassez: the third prominent hypothesis suggests that the epithelial rests of malassez, small clusters of epithelial cells found in the periodontal ligament around the tooth root, play a role in lpc formation.
this is particularly relevant given the typical location of lpcs adjacent to the tooth root.
diagnostic considerations
it is crucial to reserve the diagnosis of lateral periodontal cyst for lesions definitively located in the periodontal space, lateral to the tooth root.
distinguishing lpcs from inflammatory cysts (such as radicular cysts) and keratocystic odontogenic tumors (kcot) requires a thorough evaluation of clinical, radiographic, and pathohistological findings. specific histological features, such as the nature of the epithelial lining and the presence or absence of keratinization and inflammation, are key to accurate differentiation.
contextualizing research in brazil
while the core of this discussion focuses on lateral periodontal cysts, it's important to acknowledge the broader context of health research in regions like são josé dos campos, brazil.
for instance, studies on pre-exposure prophylaxis (prep) for hiv prevention among men who have sex with men (msm) and transgender women highlight the complexities of health interventions in diverse populations. the "imprEP" study, conducted across brazil, mexico, and peru, demonstrated the feasibility of same-day initiation of oral prep for these at-risk groups.
however, it also identified socioeconomic and educational factors, such as lower educational attainment and younger age, as potential barriers to consistent prep adherence and long-term engagement. these findings emphasize the need to address social and structural determinants of health to maximize the benefits of preventative health strategies.