Paradental cyst mimicking a radicular cyst on the adjacent tooth: case report and review of terminology

A distinctive form of paradental cyst can occur on the buccal and apical aspects of erupted mandibular molars. This cyst has peculiar clinical and radiographic features, although the microscopic findings are the same as those of odontogenic inflammatory cysts. Diagnostic and therapeutic problems can occur when this lesion is misinterpreted as a radicular cyst. The purpose of this paper is to present an additional case of a paradental cyst in the buccal and mesial aspects of a mandibular second molar involving the apical area of a mandibular first molar. The difficulty of diagnosis, treatment, and controversies regarding terminology are also discussed.     

The inflammatory paradental cyst

The inflammatory paradental cyst has previously been described as the collateral inflammatory cyst, the inflammatory lateral periodontal cyst, the paradental cyst, or the mandibular infected buccal cyst. Clinical, radiographic, and histologic features of 29 inflammatory paradental cysts diagnosed over a 5-year period were studied. The cysts occurred in relation to a partly or fully erupted tooth with a vital pulp. Twenty-seven of the cysts were located in the mandible and the remaining two in the maxilla. The mandibular cysts were in all cases associated with a molar. The observation that the cysts are diagnosed within a few years after tooth eruption and the demonstration of a statistically significant difference (p = 0.001) in age distribution and in the type of tooth involved suggest that eruption is important for the development of the cysts. The consistent finding of a hyperplastic, nonkeratinized stratified squamous epithelium with an intense inflammation in the connective tissue is in accordance with the hypothesis that inflammation is important for the development of these cysts.     

The lateral periodontal cyst: aetiology, clinical significance and diagnosis

The lateral periodontal cyst (LPC) is a relatively uncommon but widely recognized odontogenic cyst of developmental origin. It is found mostly in adults and has no sex predilection. LPC is usually discovered during routine radiographic examination, is located mainly between the roots of vital mandibular canines and premolars, and seldom causes pain or other clinical symptoms. The defect appears on radiographs as a round or teardrop-shaped, well circumscribed radiolucency. Due to its location it can easily be misdiagnosed as a lesion of endodontic origin. In this paper, two cases of lateral periodontal cysts are presented. In the first case, the patient (woman, 62 years old) complained of an asymptomatic gingival swelling in the region between the right maxillary canine and premolar. The radiographic examination revealed a well circumscribed radiolucency with a radiopaque margin between the roots of the canine and premolar. The adjacent teeth had vital pulp. Surgical enucleation of the lesion was performed and the histological examination revealed that the lesion was a "lateral periodontal cyst of developmental origin". In the second case, the patient (women, 44 years old) complained of a swelling in the area of tooth 32. During radiographic examination a well circumscribed radiolucency between the roots of the lateral incisor and the canine was discovered. Surgical enucleation of the lesion was performed and the histological examination revealed that the lesion was a "lateral periodontal cyst of developmental origin".     

Bilateral mandibular infected buccal cyst: a new image

BACKGROUND: The mandibular infected buccal cyst is an uncommon lesion associated with the permanent mandibular first or second molar in children just prior to tooth eruption. The World Health Organization includes this lesion under the category of paradental cyst and suggests the term "mandibular infected buccal cyst" (MIBC) for lesions that occur on the buccal surface of the permanent mandibular first molar in children approximately 6 to 8 years of age. We present the case of a patient with bilateral mandibular cyst affecting the second molars of an 8-year-old boy. To the best of our knowledge, this is the first case of bilateral MIBC published with a three-dimensional model made using an interactive three-dimensional (3D) implant planning system. METHODS: An 8-year-old boy presented with swelling over the buccal gingiva of his lower left first molar. He complained of pain on chewing. Clinical examination revealed a 10-mm, firm, round swelling buccal to the lower left first molar. Computed tomography with multiplanar reconstruction of the jaws showed well-defined bilateral ovoid radiolucencies at the apices of the lower left first molar and the lower right first molar. A three-dimensional study was made using the interactive 3D implant planning system showing the presence of the cyst and its relation with the molar and the dental nerve. The treatment was to enucleate the left cyst and maintain the involved tooth. RESULTS: The histopathologic diagnosis of the lesion was an MIBC. CONCLUSION: The objective of the present study is to 1) familiarize dentists and oral surgeons with the entity of the MIBC; 2) show new image techniques for the diagnosis; and 3) emphasize the appropriate treatment approach.     

Residual periodontal defects distal to the mandibular second molar 6-36 months after impacted third molar extraction

AIM: This retrospective study investigated the periodontal conditions distal to mandibular second molars 6-36 months after routine surgical extraction of adjacent impacted third molars. METHOD: Subjects were randomly selected by systematic sampling from computer records of 3211 surgical mandibular third molar extractions in the Hong Kong dental teaching hospital. Records and pre-extraction radiographs of the selected cases were retrieved. Selected subjects (n = 283) were invited for an interview followed by a clinical examination. Community Periodontal Index (CPI) protocol was used for the assessment of the general periodontal status (excluding the mandibular second molar of interest, i.e. the subject tooth) followed by a detailed periodontal examination of the subject tooth. RESULTS: In all, 158 subjects, aged 29 +/- 7 years, were examined with only 6% (nine subjects) having a highest CPI score of 4 (excluding the subject tooth), but local periodontal defects were prevalent at the distal surface of subject mandibular second molars: mean probing pocket depth (PPD) was 5.4 +/- 1.9 mm with 67% (106 subjects) exhibiting PPD >or= 5 mm and 23% (36 subjects) exhibiting PPD >or= 7 mm; mean recession was 0.8 +/- 1.0 mm; bleeding on probing 96% and suppuration on probing 5%. Multiple linear regression analysis was used to analyse the effects of 12 independent variables on the PPD at the distal surface of the involved mandibular second molar. Three possible risk indicators (P < 0.001, R2 = 0.27) associated with localised increased PPD at the distal surface of the mandibular second molars were identified: 1) third molar 'mesio-angular' impaction; 2) pre-extraction crestal radiolucency and 3) inadequate post-extraction local plaque control. CONCLUSION: The results suggest that periodontal breakdown initiated and established on the distal surface of a mandibular second molar in the vicinity of a 'mesio-angular' impacted third molar evidenced by pre-extraction crestal radiolucency in association with inadequate plaque control after extraction can predispose to a persistent localised periodontal problem.     

Clinicopathologic features of 54 cases of paradental cyst.

OBJECTIVE: The aim of the study was to evaluate the clinicopathologic features of 54 paradental cysts. METHOD AND MATERIALS: The cases were retrieved from the files of the Department of Oral Pathology of the University of S?o Paulo, in Brazil. Only case files that included complete data, radiographs, and clinical history were used for the study. RESULTS: Most of the cysts were adjacent to a partially erupted mandibular third molar; only two cysts were adjacent to mandibular second molars, and one cyst was adjacent to a first molar. Women were affected more often than were men (33:21), and most of the patients were in their second or third decades. In most cases, the affected tooth had a history of one or more episodes of pericoronitis. Histologically, these cysts presented the typical features of an inflammatory cyst, having a lining epithelium, which apparently resulted from a union between reduced enamel epithelium and oral epithelium. CONCLUSION: Development of the paradental cyst could be avoided if episodes of pericoronitis were properly treated, because the cyst is usually related to pericoronitis.     

The lateral periodontal cyst: aetiology, clinical significance and diagnosis

Abstract – The lateral periodontal cyst (LPC) is a relatively uncommon but widely recognized odontogenic cyst of developmental origin. It is found mostly in adults and has no sex predilection. LPC is usually discovered during routine radiographic examination, is located mainly between the roots of vital mandibular canines and premolars, and seldom causes pain or other clinical symptoms. The defect appears on radiographs as a round or teardrop-shaped, well circumscribed radiolucency. Due to its location it can easily be misdiagnosed as a lesion of endodontic origin. In this paper, two cases of lateral periodontal cysts are presented. In the first case, the patient (woman, 62 years old) complained of an asymptomatic gingival swelling in the region between the right maxillary canine and premolar. The radiographic examination revealed a well circumscribed radiolucency with a radiopaque margin between the roots of the canine and premolar. The adjacent teeth had vital pulp. Surgical enucleation of the lesion was performed and the histological examination revealed that the lesion was a "lateral periodontal cyst of developmental origin". In the second case, the patient (woman, 44 years old) compained of a swelling in the area of tooth 32. During radiographic examination a well circumscribed radiolucency between the roots of the lateral incisor and the canine was discovered. Surgical enucleation of the lesion was performed and the histological examination revealed that the lesion was a "lateral periodontal cyst of developmental origin".     

Unicystic ameloblastoma: a possible pitfall in periapical diagnosis

AIM: To report a clinical case of unicystic ameloblastoma previously misdiagnosed as radicular cyst. SUMMARY: A 49-year-old white male was referred to a private practitioner complaining of an asymptomatic bony hard swelling of the left posterior mandible. The patient's dental history indicated that his left mandibular first molar had been extracted approximately 10 years previously. At that time, preoperative radiographic examination demonstrated a radiolucent area of 1.5 cm diameter with well-defined margins involving the distal root of tooth 36. The lesion was diagnosed as cystic and surgery for its removal was advised, but not performed. At presentation, radiography demonstrated a well-defined 3 cm diameter radiolucency extending from the second premolar to the second molar. The lesion was enucleated and histopathological examination confirmed a diagnosis of unicystic ameloblastoma. KEY LEARNING POINTS: *Despite a clinical diagnosis of periapical disease of endodontic origin, a nonendodontic lesion may be present. *Unicystic ameloblastoma located on the periapical area of a tooth can lead to a pulp-periapical misdiagnosis, and should be considered in differential diagnosis. *All tissue specimens recovered in apical surgery should be submitted to histopathological analysis.     

Odontogenic carcinoma occurring in a dentigerous cyst: case report and clinical management

This case report describes an unusual odontogenic carcinoma, which was detected during routine periodontal examination. The lesion occurred in a dentigerous cyst associated with an impacted third molar in an otherwise asymptomatic 66-year-old male patient. The impacted tooth and lesion were excised based on evidence of radiographic change and clinical findings. An unusual histopathologic presentation is reported. The treatment provided for this tumor and the management of impacted teeth is reviewed.     

Paradental cysts: a role for food impaction in the pathogenesis? A review of cases from Northern Ireland

We present the clinical, radiographic and histological findings of 15 paradental cysts. These were the second most common type of cyst associated with mandibular third molars, comprising 25% of all lesions at this site. Ten patients were aged 30 years or younger and 13 gave a history of pericoronitis. There was a close relationship between the site of the cyst and the angle of the impacted tooth; the cyst lay mesially to two mesioangularly impacted teeth, buccal to two vertically impacted teeth and distal/distobuccal to the remainder, all but one of which were distoangular in impaction. The pericoronal follicular space was preserved in nine cases, a useful diagnostic sign. Most cysts were lined with epithelium that resembled that seen in radicular cysts, although the lining of three cysts resembled that of unicystic ameloblastoma, a potential diagnostic pitfall. We propose that the relation between location of cyst and angle of impaction points to a role for food impaction in the pathogenesis of paradental cysts.     

Unusual surgical approach in a bilateral case of mandibular buccal infected cyst

In the new edition of WHO's "Histological typing of odontogenic tumors", the mandibular infected buccal cyst, that is associated with the lower first or second permanent molars, is considered a paradental cyst as well as the inflammatory collateral cyst, which is usually related to the lower third molar. The lesion occurs on the buccal and lateral aspects of the roots of mandibular molars with vital pulp, at the eruption time, in children aged between 6 and 10 years. The inflammation is always present in these cysts and may have an important role in their pathogenesis because it stimulates hyperplasia and cystic change of the reduced enamel epithelium or the epithelial cell rests of Malassez. The authors report the case of a 7-year-old girl, in whom both first mandibular molars were affected by an infected buccal cyst. A different surgical approach was performed with marsupialization on the left side and cystectomy on the right side. The case reported here seems to be interesting because it is the second well documented case of bilateral mandibular infected cyst associated with unerupted molars and because the adopted treatment differs from the therapeutical approach suggested in the literature. A 6-year follow-up demonstrates a correct dental and bone evolution on both mandibular molar sides.     

Mandibular second molar periodontal status after third molar extraction.

BACKGROUND: Extraction and treatment of third molars have been cited as causing periodontal problems. To evaluate the long-term effects of third molar extraction on the periodontal health of the mandibular second molar, a comparison of the periodontal status was performed around 2 groups of mandibular second molars, with and without third molar extraction. METHODS: A total of 312 sites in 57 adult periodontitis patients were examined and the buccal and lingual locations of the mesial and distal root surfaces around the second molars were recorded. Two-hundred and thirty-two sites were experimental teeth; i.e., third molars had been surgically removed more than 5 years ago, 80 sites served as control molars; i.e., congenitally missing third molars. Clinical periodontal parameters including probing depth, attachment loss, and gingival recession and radiographic intrabony level were measured. The effects of the surgery and the examination (buccal or lingual) locations on the measurements were statistically analyzed. RESULTS: Neither extraction history nor examination location affected the probing depth on mesial surfaces. However, significant effects of the surgical history on the probing depth were observed on the distal surfaces. Similar results of greater attachment loss and radiographic alveolar bone loss were observed only at the distal sites of the experimental group. In addition, the increased radiographic bone loss was only found at the distal sites (adjacent to the surgical location) and not at the mesial sites (distant from the surgical location) on the experimental group. CONCLUSIONS: In this study, greater periodontal breakdown, including probing depth, attachment loss, and radiographic alveolar bone loss, was found at the distal sites, but not at the mesial sites, of the experimental molars where the third molar was surgically extracted compared with the control teeth (no surgery). In the experimental molars, more radiographic bone loss was found at the sites adjacent to the surgical location than at the sites distant to the surgical location. Therefore, we suggest that the surgical removal of the mandibular third molar may lead to a periodontal breakdown on the distal surface of the second molar. Periodontal re-evaluation after the initial healing of third molar extraction is indicated.     

The inflammatory paradental cyst: a critical review of 342 cases from a literature survey, including 17 new cases from the author''s files

BACKGROUND: A total of 325 cases of inflammatory paradental cysts (IPCs) and 17 own cases were reviewed. Although known since 1930, the IPC is still unrecognized by many clinicians. The IPCs show a relative frequency of 0.9-4.7%. The majority of cysts occur distally or distobuccally to vital, permanent mandibular molars with a history of pericoronitis (IPC/3rd mandibular molar alone accounts for 64.9%). Radiologically, the cyst appears as a well-defined, semilunar unilocular radiolucency. MATERIALS AND METHODS: Cases of inflammatory paradental cysts and related lesions were retrieved from a worldwide literature survey. In addition, 17 new cases from the files of the authors have been added. RESULTS: The mean ages for patients with IPC/1st, 2nd and 3rd mandibular molars are 8.7, 17.4 and 27.6 years, respectively. The male:female ratio was 1 : 0.9 for IPC/1st and 2nd mandibular molars, and 1 : 0.4 for 3rd mandibular molar. CONCLUSION: Reduced enamel epithelium, cell rests of Malassez and remnants of the dental lamina stimulated by inflammation are thought to play a role in the pathogenesis of IPC. Histological features are indistinguishable from those of the inflammatory, periapical (radicular) cyst.     

智齿拔除后羟基磷灰石恢复牙槽骨高度的临床研究

目的:研究拔除下颌智齿后,用羟基磷灰石人工骨填塞牙槽窝,修复第二磨牙牙槽骨高度的方法。方法:拔牙术后即刻植入羟基磷灰石微粒于牙槽窝内,术后12周进行第二磨牙牙槽高度、牙周袋深度、牙龈附着、龈指数的检查。结果:第二磨牙牙槽高度得到较好修复。结论:智齿拔除后即刻植入羟基磷灰石人工骨有利于第二磨牙远中牙槽高度的恢复。     

Orthodontic extraction of mandibular third molar to avoid nerve injury and promote periodontal healing

Aim: Impacted mandibular third molar extraction is a common procedure in oral surgery, not without risk of nerve injury and periodontal defects on the distal aspect of the adjacent second molar. The "orthodontic extraction" is proposed as a method to avoid mandibular nerve injury during the extraction of a deeply embedded third molar and to prevent or limit such periodontal problems.
Material and Methods: A 28-year-old man presented a deeply impacted left mandibular third molar that required extraction. Radiographs revealed a very slight quantity of bone at the distal surface of the adjacent second molar. The third molar was extruded according to the "orthodontic extraction" technique. A 3-month retention phase elapsed to ensure adequate bone maturation and the tooth was finally extracted.
Results: No neurological complications occurred. A minimal residual bone defect at the distal surface of the adjacent second molar was detected radiographically both post-operatively and at the 3-year follow-up.
Conclusions: Orthodontic extraction makes third molar removal easier and has no neurological risk. This procedure, followed by a 3-month retention phase, appears to be effective in preventing or limiting the development of periodontal problems on the distal aspect of the adjacent second molar.     

Primary failure of tooth eruption associated with secondarily inflamed dental follicle: inflammatory follicular cyst?

Primary failure of eruption represents a cessation of tooth eruption before emergence not due to a physical barrier or abnormal position and has no systemic cause. This failure of tooth eruption is rare phenomenon and it has not been associated with alterations of dental follicle. This case report describes a permanent right first molar with primary failure of eruption at the inferior border of the mandible presenting microscopic, clinical and radiographic findings compatible with follicular cystic lesion. The follicular tissues of this molar showed microscopic aspects of inflammation. Thus, pericoronal tissues surrounding long-term unerupted teeth with primary failure of eruption has potential to develop into odontogenic cysts. The lesion presented herein probably arose in association with a periodontal pocket mesial to the adjacent second molar, representing an atypical inflammatory follicular cyst. This case shares etiological, radiological and microscopic features with the usual form of the inflammatory follicular cyst associated with infected primary teeth, except for the infection pathways reaching the tooth follicle. The controversies regarding the terminology for this cyst are discussed.     

Infected paradental cysts in children: a clinicopathological study of 15 cases

We report the clinical, radiographic and histological features of 15 paradental cysts of the first and second molars and recommend conservative surgical treatment. Twelve young patients were operated on for 15 paradental cysts of the first and second molars, and had conservative operations with partial preservation of the mandibular cortical bone. After 2 years there had been no recurrences. The differential diagnosis of paradental cyst was fundamental to allow the correct treatment and the early diagnosis of lesions on the opposite side. The maintenance of periodontal hygiene in the immediate and late postoperative periods was an aid to ensure complete remission of the lesions.     

Association between the presence of a partially erupted mandibular third molar and the existence of caries in the distal of the second molars

The objective of this study was to verify, using periapical radiographs, whether a partially erupted mandibular third molar is a factor in the presence of dental caries on the distal surface of the adjacent second molar. Two-forty six high quality periapical radiographs were selected, each showing a partially erupted mandibular third molar. The variables analyzed were: tooth number; gender; age; radiographic presence of caries on the distal surface of the adjacent molar; Pell and Gregory classification; Winter classification; angulation and distance between the second and mandibular third molar. The examiners were previously calibrated to collect data (kappa statistics from 0.87 to 1.0). The prevalence rate of caries on the distal surface of the second molar was 13.4%. In the logistical multivariate regression analysis, the angulation (OR=8.5; IC95%: 1.7-43.8; p=0.011) and the gender (OR=3.3; IC95%: 1.4-7.7; p=0.005) remained statistically significant after an age adjustment was made. The results indicate that the presence of a partially erupted mandibular third molar with an angulation of 31 degrees or more, is a risk factor for caries on the distal surface of the mandibular second molars.     

Unerupted mandibular second primary molar with an unusual histopathological finding: a case report

This is the case of a healthy 6-year old female with a clinically absent right mandibular second primary molar with no history of that tooth ever being present. Radiographic examination revealed a well-circumscribed pericoronal radiolucency surrounding the mandibular right primary second molar. The mandibular right second premolar was displaced mesially. Treatment consisted of enucleation of the lesion with removal of both the unerupted primary second molar and second premolar. The histopathology of the excised lesion revealed a hyperplastic dental follicle with a focal proliferation of odontogenic epithelium and duct-like structures, probably representing an incipient adenomatoid odontogenic tumor.