Glandular odontogenic cyst: An updated analysis of 169 cases reported in the literature

Glandular odontogenic cyst misdiagnosed and treated as a periapical inflammatory lesion for 6 years in an older adult

OBJECTIVES

To document the case of a patient who underwent several endodontic treatments due to a glandular odontogenic cyst misdiagnosed as an inflammatory periapical lesion.

BACKGROUND

Glandular odontogenic cysts behave more aggressively, while others have an indolent course. There is limited information on this cyst in the gerodontologic literature.

MATERIALS AND METHODS

A 76-year-old male patient presented with an asymptomatic expansive lesion in the anterior mandible resistant to several endodontic treatments. Cone-beam computed tomography revealed a multilocular osteolytic lesion measuring 6.0 × 4.0 cm, with cortical bone perforation.

RESULTS

Histopathological analysis of a biopsy specimen was consistent with glandular odontogenic cyst. The patient underwent marginal mandibulectomy with preservation of the base of the mandible.

CONCLUSION

A strict diagnostic process is important to avoid unwanted consequences, particularly in the geriatric population.

Recurrence of Glandular Odontogenic Cysts: A Systematic Review

BACKGROUND

The glandular odontogenic cyst (GOC) is a benign developmental cyst of the jaws that is characterized by a high recurrence rate.

METHODS

A systematic review is presented of reported cases, case series, and retrospective studies of recurrent cases of glandular odontogenic cysts, to determine the overall and detailed demographic features with documentation of the specific histologic features of the initial presentation of each cyst. Searches of detailed databases were carried out to identify articles published in the English language from 1988 to 2023. The variables were demographics, patient symptoms, cyst location, radiographic features, histopathological findings, type of treatment, and minimum eight months of follow-up.

RESULTS

Eighteen cases were identified: with an equal gender presentation of 50% females and 50% males. The average age was 44.7. The mean size was 3.5 cm. The most common location was in the anterior mandible in 50% (n = 9) of cases, followed by the posterior mandible 27.8% (n = 5). Most patients were asymptomatic 55.6% (n = 10). The most common histologic features at first diagnosis were mucous cells in 88.9% (n = 16), variable thickness with 83.3% (n = 15), eosinophilic cuboidal cells 88.9% (n = 16), microcysts 83.3% (n = 15), and clear cells 77.8% (n = 14) cases.

CONCLUSION

GOC has an aggressive behavior. Evidence was not conclusive to link any single or combination of histologic features to recurrence, and the strongest correlation for recurrence was the type of treatment. Since this is an uncommon cyst, more cases are needed. Follow-up should continue for at least five years, because recurrences were higher between years 3 and 5.

Glandular Odontogenic Cyst in the Anterior Mandible: A Case Report of a Conservative Approach and a Recurrence Detection

PURPOSE

The glandular odontogenic cyst (GOC) is considered a rare developmental cyst, with an odontogenic origin and both epithelial and glandular characteristics, with less than 200 reported cases in the literature.

METHODS

In the present case, a 29-year-old man was referred for evaluation of an asymptomatic slow-growing swelling in the anterior region of the mandible, with one-year history. The patient's medical history did not reveal any systemic alteration. The extraoral examination did not show enlargement of the facial contour and the intraoral examination showed vestibular and lingual swelling. Panoramic radiography and CT scan revealed a well-defined unilocular radiolucent lesion involving the inferior incisors and canines bilaterally.

RESULTS

Histopathological analysis revealed multiple cysts lined by stratified epithelium with varying thickness and characteristics, in addition to duct-like structures filled with PAS-positive amorphous material, suggestive of GOC. Conservative treatment was performed through surgical curettage, peripheral ostectomy of the surgical site and apicectomy of the teeth involved in the lesion. There was one recurrence, which was detected in postoperative follow-up, leading to a new surgical approach.

CONCLUSIONS

Fifteen months after the second procedure, no signs of recurrence were identified, and bone neoformation within the surgical site occurred, supporting that a conservative approach for the treatment of GOC is viable.

Posterior mandibular glandular cyst: A rare case report

BACKGROUND

Odontogenic glandular cyst (GOC) is one of the uncommon cysts of the jaws with difficult diagnosis due to the presence of many clinical and histopathological overlaps with other odontogenic lesions, and the definitive diagnosis is only possible by histological examination. It is initially asymptomatic and affects the anterior mandible with no gender predilection. Surgical resection is the preferred treatment due to the high rate of recurrence. To date, there are less than 200 documented cases worldwide.

CASE PRESENTATION

A 33-year-old female patient who consulted the Department of Oral and Maxillofacial Surgery due to numbness and swelling. She has no medical history with medications or genetic diseases. The lesion was diagnosed as an odontogenic glandular cyst, and then treated with surgical resection and plate-and-screw replacement.

CLINICAL DISCUSSION

Odontogenic Glandular cyst is an uncommon cyst it is difficult to diagnose depending on clinical features and radiographic imaging only, the definitive diagnosis is based on histological examination. The preferred treatment is surgical resection with safety edges.

CONCLUSION

More care should be given to report this rare entity to assure accurate and early diagnosis.

Glandular Odontogenic Cyst: a Case Report and Literature Review

Background

The glandular odontogenic cyst is now a well-known entity comprising < 0.5% of all odontogenic cysts with a recent review tabulating about 200 cases in the English literature. Glandular odontogenic cyst shows epithelial features that simulate salivary gland or glandular differentiation. The importance of glandular odontogenic cyst relates to the fact that it has a high recurrence rate and shares overlapping histologic features with central mucoepidermoid carcinoma. The purpose of this paper is to describe the clinical, radiological, and histopathological features of a case of glandular odontogenic cyst with the course of treatment and 9-years follow-up, followed by a review of the literature.

Methods

A 63-year-old male was referred for further investigation of a mandibular radiolucency observed by his general dental practitioner. The main complaint was a murmuring sensation in the lower jaw right side. Radiological examination revealed a well-defined, unilocular, radiolucent lesion, involving the right mandible with 17 and 68 mm in mediolaterally and anteroposterior dimension, respectively.

Results

A total enucleation of the cystic lesion and surgical extraction of tooth #46, #47 and #48, was performed under local anaesthesia. Histopathologic examination revealed a glandular odontogenic cyst.

Conclusions

Glandular odontogenic cyst shows no pathognomonic clinico-radiographic characteristics, and therefore in many cases it resembles a wide spectrum of lesions. Diagnosis can be extremely difficult due to histopathological similarities with dentigerous cyst, lateral periodontal cyst and central mucoepidermoid carcinoma. Therefore a careful histopathological examination and a long-term follow-up (preferably seven years) are required to rule out recurrences.

Cystic Lesions of the Jaws: The Top 10 Differential Diagnoses to Ponder

BACKGROUND

Cystic lesions of the gnathic bones present challenges in differential diagnosis. This category includes a smorgasbord of odontogenic and non-odontogenic entities that may be reactive or neoplastic in nature. While most cystic jaw lesions are benign, variability in biologic behavior makes distinction between these entities absolutely crucial.

METHODS

Review.

RESULTS

Two clinical cases are presented in parallel and are followed by an illustrated discussion of the ten most likely differential diagnoses that should be considered when confronted with a cystic jaw lesion. Strong emphasis is placed on the histologic differences between these entities, empowering readers to diagnose them with confidence. Perhaps even more importantly, the more common diagnostic pitfalls in gnathic pathology are discussed, recognizing that a definitive diagnosis cannot be rendered in every situation. The histologic diagnoses for the two clinical cases are finally revealed.

CONCLUSION

Cystic lesions of the maxilla and mandible may be odontogenic or non-odontogenic. The most common cystic lesions are the reactive periapical cyst, and the dentigerous cyst (which is developmental in nature). It is important to note that cystic neoplasms also occur in the jaws, and that the presence of inflammation may obscure the diagnostic histologic features of lesions like odontogenic keratocyst and unicystic ameloblastoma. Ancillary testing is of limited diagnostic value in most scenarios. However, both clinical and radiographic information (such as the location, size, duration, associated symptoms, and morphology of the lesion in its natural habitat) are significantly useful.

Frequency and Demographic Profile of Odontogenic Cysts in Riyadh, Saudi Arabia: Retrospective Multicenter Study

Odontogenic cysts (OCs) are etiologically diverse conditions with a shared origin in the jaws. Unfortunately, there is a scarcity of published data regarding OC frequency, treatment, and follow-up information in Saudi Arabia, especially from tertiary centers.

OBJECTIVES

The study aims to assess the relative frequency, clinicopathological features, treatment, and follow-up of OCs in three tertiary medical centers.

METHODS AND MATERIAL

OCs were identified from King Abdulaziz Medical City, King Fahad Medical City, and Prince Sultan Military Medical City from January 2010 to December 2021.

RESULTS

Three hundred and seventy-two cases of OCs were identified from the archive of three medical centers in Riyadh; one hundred and forty-nine (40%) cases were retrieved from Prince Sultan Military Medical City. The mean age of all OCs was 32 years (range 2-90), with 225 (60.4%) cases occurring in males. There was an almost equal distribution of OCs between the maxilla (47.0%) and the mandible (53.0%). The apical radicular cyst (ARC) accounted for half of the cases, followed by dentigerous cyst (DC) (29.3%) and odontogenic keratocyst (OKC) (14.2%). Enucleation was the most common treatment modality (52.8%), followed by excision (35.0%). Thirteen cases showed recurrence: one ARC, four DCs, and eight OKCs.

CONCLUSION

This is the first large multicenter study of OCs in Riyadh, Saudi Arabia. All three centers showed that ARC was the most common, followed by DC and OKC.

Clinical and radiologic spectrum of glandular odontogenic cysts: A multicenter study of 92 cases

OBJECTIVE

The purpose of this multicenter retrospective study was to report the clinical and radiologic features of 92 glandular odontogenic cysts (GOCs) diagnosed over a 20-year period.

STUDY DESIGN

Histologically confirmed cases of GOC were retrospectively reviewed from 4 oral pathology laboratories in South Africa and Brazil to categorize the clinical and radiologic spectrum of GOCs.

RESULTS

The mean age of patients was 46 years (range 17-87) with a male-to-female ratio of 1.2:1. GOCs had a mandibular predilection (68%), with 42% of all cases located anteriorly. Additionally, 42% of cases crossed the midline. Radiologically, most lesions were unilocular (53%) and uniformly radiolucent (97%), with well-demarcated borders (93%). Cortical expansion (62%), loss of cortical integrity (71%), and maxillary sinus (67%) and nasal cavity encroachment (72%) were common findings. Significant differences in lesions between the 2 countries were discovered in sex predilection, clinical signs and symptoms, and lesion locations within the mandible and maxilla.

CONCLUSION

GOCs present with a wide spectrum of clinical and radiologic features, ranging from cysts with typical GOC-like presentations to more aggressive lesions. The need for advanced imaging in the surgical planning of GOCs exhibiting radiologic signs of aggression is justified based on the high recurrence rate.

Glandular odontogenic cysts: a collaborative investigation of 22 cases and proteins related to invasiveness

BACKGROUND

A glandular odontogenic cyst has an intriguing, aggressive behaviour whose mechanisms have not yet been clarified.

OBJECTIVE

To conduct a collaborative cross-sectional study on the clinical, demographic, microscopic, and immunohistochemical characteristics of glandular odontogenic cysts, emphasizing the histopathological characteristics and expression of proteins related to invasiveness.

METHODS

Twenty-two cases of glandular odontogenic cyst from three oral and maxillofacial pathology services in Brazil were selected from 1988 to 2018. Clinical and demographic data were collected. Histopathological features were evaluated in detail. Sixteen cases of glandular odontogenic cyst were also submitted to immunohistochemistry to detect MT1-MMP, TKS4, TKS5, and cortactin, the key regulators of invadopodia formation.

RESULTS

GOCs were primarily seen in men over 40 years of age, in the posterior mandible and the anterior maxilla as a unilocular, radiolucent lesion. All cases presented hobnail cells, clear cells, and variable thickness of the lining epithelium, three of the ten key histopathological parameters to be evaluated in glandular odontogenic cysts. Immunohistochemistry revealed a greater expression of the studied proteins in the glandular odontogenic cysts than in the controls (p <0.0001).

CONCLUSION

Overexpression of proteins that regulate cell invasiveness was identified, and the present study's findings suggest that invadopodia activity is a possible mechanism used by glandular odontogenic cysts to promote local invasion, which could partly explain its intriguing biological behaviour.

Scalloped border as a possible diagnostic aid for differentiating jaw lesions: A pictorial essay

Purpose

The aim of this study was to introduce a category of jaw lesions comprising cysts and tumors associated with scalloped borders.

Materials and Methods

General search engines and specialized databases including Google Scholar, PubMed, PubMed Central, and Scopus, as well as an authoritative textbook, were used to find relevant studies by using keywords such as “jaw lesion,” “jaw disease,” “scalloping,” “scalloped border,” “scalloped margin,” “irregular border,” and “irregular margin.” Out of 289 articles, 252 records were removed because they were duplicates, did not have a relevant title, or did not mention the frequency of findings described using the term “scalloped border.” Finally, 37 closely related articles were chosen.

Results

According to the relevant literature, scalloped borders are found most frequently in ameloblastoma, followed by simple bone cyst, central giant cell granuloma, odontogenic keratocyst, and glandular odontogenic cyst.

Conclusion

The lesions most frequently reported to have scalloped borders are ameloblastoma, central giant cell granuloma, odontogenic keratocyst, simple bone cyst, and glandular odontogenic cyst.

Nonendodontic periapical lesions: a retrospective descriptive study in a Brazilian population

Background

Several nonendodontic diseases can occur in the periapical region, resembling endodontic inflammatory conditions. Therefore, the aim of the present study was to determine the frequency of nonendodontic periapical lesions diagnosed in a Brazilian population.

Material and Methods

The files of two Oral Pathology laboratories were reviewed and all cases including at least one clinical diagnosis of endodontic periapical lesions were selected for the study. After initial selection, demographic and clinical data, clinical diagnosis and final diagnosis were reviewed and tabulated. Final diagnosis included endodontic periapical lesions, and benign and malignant nonendodontic periapical lesions. Data were descriptively and comparatively analyzed among the three groups, with a significance level of 5% (p<0.05).

Results

Nonendodontic periapical lesions were identified in 208 (19%) out of the 1.125 registries included in the final sample. Benign nonendodontic periapical lesions (200 cases, 18%) were mostly odontogenic keratocysts, ameloblastomas, nasopalatine cysts, dentigerous cysts, glandular odontogenic cysts, and benign fibroosseous lesions. Malignant nonendodontic periapical lesions (8 cases, 1%) included carcinomas, adenocarcinomas, and melanoma. In general, nonendodontic periapical lesions were more common in males and in the posterior mandible (p>0.05).

Conclusions

The frequency of nonendodontic periapical lesions was high and, although the general distribution was similar to the results from other populations, some features were probably associated with the profile of the studied populations and to the methods applied in the present study. Knowledge on differential diagnosis of endodontic and nonendodontic periapical lesions is essential to avoid unnecessary treatments and diagnostic delay in routine dental practice.

Key words:Differential diagnosis, nonendodontic, periapical lesion, pulp necrosis.

Unique case of glandular odontogenic cyst showing mucoepidermoid carcinoma-like islands in cystic wall

Glandular odontogenic cyst (GOC) is a very rare jaw cyst accounting for 0.2% of all odontogenic cysts. It presents usually in adults with a slight male predominance. It shows radiological, histopathological and even immunohistochemical overlap with low grade intraosseous mucoepidermoid carcinoma (MEC) but their distinction is crucial. A 57-year-old woman with bilocular radiolucency in the anterior mandible crossing the midline is described here. Microscopy features were consistent with glandular odontogenic cyst but multiple MEC-like islands were seen in the capsule, creating a diagnostic head trip with low grade intraosseous MEC. However, the absence of cellular atypia and epidermoid and intermediate cells led to a final diagnosis of GOC, with close follow-up of the patient recommended. This rare finding shows the relation between GOC and MEC or the origin of MEC from GOC.

A slow-growing anterior maxillary mass

A 43-year-old-male with no medical conditions presented to his dentist with a left maxillary swelling present for 1 year. His physical exam revealed a 2-cm × 2-cm, poorly demarcated, firm mass in the left anterior maxilla causing mobility of the associated teeth. He had a bluish discoloration of the anterior maxillary mucosa. A computed tomographic scan demonstrated a homogeneous and uniformly radiolucent, well-defined mass in the left anterior maxilla primarily involving the alveolus and the roots of teeth 7-12. The mass caused expansion and tooth displacement. An incisional biopsy was done and MUC 4 staining was diffusely positive so the diagnosis of low-grade fibromyxoid sarcoma (LGFMS) was made. He underwent wide local excision and reconstruction with a fibula free flap and a three-dimensionally printed, implant-retained prosthesis. The final pathology confirmed the diagnosis of LGFMS, stage pT4aN0M0, with negative margins. The patient had no evidence of recurrence at 1-year follow-up.

Glandular Odontogenic Cyst-A Case Series

The glandular odontogenic cyst (GOC) is an uncommon jawbone cyst with a challenging diagnosis because of the presence of several clinical and histopathologic overlaps with other odontogenic lesions and central mucoepidermoid carcinoma. To date, less than 200 cases of GOC have been published in the literature with reliable clinical and histopathologic information. Furthermore, the lack of a well-documented GOC case series impairs a more detailed understanding about the biological behavior and appropriate management of the lesion. Therefore, in this study, we report 3 well-documented cases of GOC in the literature. In one of the cases, the incisional biopsy was misdiagnosed as a dentigerous cyst, and the lesion recurred. Therefore, we also discuss key points regarding the diagnosis and treatment of GOC.

Ameloblastoma with mucous cells: A clinicopathological, BRAF mutation, and MAML2 rearrangement study

OBJECTIVES

To investigate the clinicopathological features, BRAF V600E mutation, and MAML2 rearrangement of ameloblastoma with mucous cell differentiation.

MATERIALS AND METHODS

Five cases of ameloblastoma with mucous cell differentiation were retrospectively studied. Clinicopathological features, BRAF V600E mutation, and MAML2 rearrangement were analyzed. Follow-up information was available for all cases.

RESULTS

Of five cases, two cases were male and three were female, aged 18-55 years. Four cases were located in the mandible and one case in the maxilla. Histologically, four of the five cases (80%) presented with cystic features and three of the five cases (60%) with varying degrees of squamous metaplasia. The mucous cells were located in the epithelial islands or the luminal aspect of the cystic cavities. The BRAF V600E mutation was found in three of five cases (60%). All the cases showed no MAML2 rearrangement. Two cases were recurrent lesions, and one case had a local recurrence during the follow-up.

CONCLUSIONS

Ameloblastoma with mucous cell differentiation is closely related to the cystic features, squamous metaplasia, and shows a high prevalence of BRAF V600E mutation. The absence of MAML2 rearrangement reveals that ameloblastoma with mucous cell differentiation and central mucoepidermoid carcinoma (MEC) are two distinct tumor entities.

Odontogenic keratocyst and ameloblastoma: radiographic evaluation

OBJECTIVES

To describe the radiographic features of odontogenic keratocysts (OKCs) and ameloblastomas and to compare the radiographic findings between these 2 lesions.

METHODS

Radiographs of OKCs and ameloblastomas were retrospectively reviewed. Location, border, shape, association with impacted tooth, tooth displacement, root resorption, and bone expansion were evaluated. Chi-squared or Fisher's exact tests were used for statistical analysis. A p value < 0.05 was considered to indicate statistical significance.

RESULTS

One hundred OKCs and 101 ameloblastomas were reviewed. The ratios of maxilla to mandible were 1:1.4 and 1:9.1 in OKCs and ameloblastomas, respectively. All evaluated features significantly differed between OKCs and ameloblastomas (p ≤ 0.001). Most OKCs showed smooth border (60%) and unilocular shape (82%), while most ameloblastomas showed scalloped border (77.2%) and multilocular shape (68.3%). Association with impacted tooth was found in 47% of OKCs and 18.8% of ameloblastomas. Adjacent tooth displacement was found in 33.7% of OKCs and 55.8% of ameloblastomas. Root resorption was more common in ameloblastomas (66.7%) than in OKCs (7%). Bone expansion was also more common in ameloblastomas (96.3%) than in OKCs (63.6%).

CONCLUSION

A unilocular radiolucent lesion with smooth border, no adjacent tooth displacement, no root resorption and causing mild or no bone expansion is suggestive of an OKC rather than an ameloblastoma.

Glandular odontogenic cyst-Report of a rare case

Glandular odontogenic cyst is a rare developmental odontogenic cyst that bears similarity to several other odontogenic lesions. Till 2017, only 169 such cases have been reported in the literature. Herein, we describe one more case of it occurring in a 35-year-old female patient.

Differential Diagnosis of Periapical Radiopacities and Radiolucencies

Periapical pathoses represent changes noted at the apices of teeth within the alveolar process that are suspected on examination, visualized via imaging, and confirmed via histopathology. They can be bone forming or destructive. There are pathologic entities that show both types of changes at the apical regions. These lesions must be identified if they are odontogenic in origin because treatment modalities differ. This article discusses identification of radiopaque and radiolucent lesions noted on radiographs. The common opacities and lucencies are described. When required, advanced imaging is used to depict changes within the bone near the periapical regions of mandibular and maxillary teeth.

Demographic and Clinical Characteristics of 5294 Jaw Cysts: A Retrospective Study of 38 Years

The aim of the present study is to report the demographic and clinical characteristics of all jaw cysts diagnosed in a single Oral Pathology Department. 5294 cases of jaw cysts diagnosed during a 38-year period were retrospectively collected and classified according to the latest classification of Head and Neck Tumors of the World Health Organization. The patients' gender and age, as well as the main clinical features of the cysts were retrieved from biopsy report forms. Jaw cysts were more common in male patients, with a male to female ratio of 1.6:1. Most patients were in the 4th-6th decade of life, with a mean age of 42.3 ± 16.1 years. There was no jaw predilection and the majority of lesions were more commonly encountered in the anterior region of the maxilla, followed by the molar region of the mandible. The most common jaw cyst was radicular cyst followed by dentigerous cyst, residual cyst and odontogenic keratocyst. The majority of jaw cysts are of inflammatory origin and represent a sequale of pulp necrosis. However, other type of jaw cysts may also be found.

Adenomatoid odontogenic tumor: An updated analysis of the cases reported in the literature

PURPOSE

To review the clinical and radiographic features of the available data published on adenomatoid odontogenic tumor (AOT) with special emphasis on the comparison of its variants.

METHODS

An electronic search was undertaken in July 2018. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm the diagnosis.

RESULTS

A total of 436 publications reporting 1558 cases were included, of which 739 follicular, 247 extrafollicular, and 30 peripheral AOTs. Impacted canine is associated with follicular AOTs in almost 70% of the cases. AOTs were more prevalent in females, in the second decade of life, in maxillae, in anterior region of the jaws, and most are asymptomatic, with a considerable number of lesions presenting cortical bone perforation. Most of the lesions were treated by enucleation. Some cases of recurrence were reported in the literature, but only one was well documented. No difference was found when comparing the clinical/radiological features of the follicular, extrafollicular, and peripheral variants.

CONCLUSIONS

Adenomatoid odontogenic tumor variants do not show distinctive clinical radiological features. Recurrence of AOT is very rare, which justify its conservative management.

Melanotic neuroectodermal tumour of infancy of the jaws: an analysis of diagnostic features and treatment

The purpose of this study was to integrate the available published data on melanotic neuroectodermal tumour of infancy (MNTI) of the jaws into a comprehensive analysis of its clinical/radiological features, with emphasis on the predictive factors associated with recurrence. Eligibility criteria included publications with sufficient clinical/radiological/histological information to confirm the diagnosis. A total of 288 publications reporting 429 MNTI cases were included. MNTIs were slightly more prevalent in males and markedly more prevalent in the maxilla. Most of the lesions were asymptomatic, presenting cortical bone perforation and tooth displacement. Nine lesions were malignant, with metastasis in five cases. Enucleation was the predominant treatment (67.2%), followed by marginal (18.4%) and segmental resection (6.1%). Eighty-one of 356 lesions (22.8%) recurred. Recurrence rates were 61.5% for curettage, 25.3% for enucleation alone, 16.2% for enucleation+curettage, 20.0% for enucleation+peripheral osteotomy, 11.3% for marginal resection, 10.0% for segmental resection, 30.0% for chemotherapy, and 33.3% for radiotherapy. Enucleation and resection presented significantly lower recurrence rates in comparison to curettage. Curettage appears not to be the best form of treatment, due to its high recurrence rate. As resection (either marginal or segmental) is associated with higher morbidity, enucleation with or without complementary treatment (curettage or peripheral osteotomy) would appear to be the most indicated therapy.

Odontogenic myxoma: An updated analysis of 1,692 cases reported in the literature

The aim of the present study was to integrate the available data published on odontogenic myxoma (OM) into a comprehensive analysis of its clinical/radiological features. Electronic search undertaken in January/2018, looking for publications reporting cases of OM. A total of 377 publications were included. We identified 1,692 lesions, and 695 were used for the analysis of recurrence. There is a predominance of OMs in females and in mandibles. OMs usually present with bone expansion, asymptomatic cortical perforation, and a multilocular appearance. Lesion location (maxilla/mandible), bone expansion, cortical bone perforation, locular radiological appearance, tooth resorption, odontogenic epithelial rests, or angular septa are not associated with recurrence. While curettage (31.3%) showed the highest recurrence rate, marginal resection (1.3%) and segmental resection (3.1%) showed the lowest values. Enucleation + peripheral osteotomy (6.7%) showed better results than enucleation (13.1%) or enucleation + curettage (12.7%). In comparison with unilocular lesions, multilocular ones were significantly more prevalent in mandibles, more often presented expansion and cortical bone perforation, had larger mean size, and were more often treated by segmental resection. Conservative surgical procedures are associated with higher probability of recurrence of OM. Taking into consideration the recurrence rate and morbidity associated with different surgical treatments, tumor enucleation followed by peripheral osteotomy should be considered as the first therapeutic choice.

[Cystic lesions of the jaws]

Cystic lesions of the jaws comprise a spectrum of inflammatory, developmental and neoplastic changes that can clinically appear strikingly similar. Squamous cell metaplasia due to superinfection can further blur the histologic hallmarks of the individual lesions. In this article an overview of the most important differential diagnoses and the novelties of the latest World Health Organisation (WHO) classification on head and neck tumours released in early 2017 is provided. In contrast to the previous edition, odontogenic cysts have been re-introduced and several changes in terminology and taxonomy have been complemented.