Study of maxillary and mandibular cystic lesions Poster No.: C-1428 Congress: ECR 2013 Type: Educational Exhibit Authors: M. L. Rozas Rodríguez, M. E. Banegas Illescas, M. Y. Torres Sousa, R. M. Fernández Quintero, R. Quintana de la Cruz, R. Ruiz Martinez; Ciudad Real/ES Keywords: Head and neck, CT, Cysts DOI: 10.1594/ecr2013/C-1428 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 28
Learning objectives To show the different lesions with a cystic morphology in panoramic radiography and CT scan that locate in the maxilla and mandible. Background Cystic mandibular and maxillary lesions that we frequently see in facial and paranasal sinuses studies. CT with panoramic radiography are the diagnostic tools used in their evaluation. The possibility of reconstructions in different planes help us in the diagnosis. We make a review of the diseases seen at our institution in the last three years. We study them with a 40 detector multidetector CT scan (Brillance, Philips, Holland), with a 0'9 mm thickness and an interval of reconstruction of 0'45 mm, in the axial plane and we make multiplanar and 3D reconstructions. Occasionally curved reconstructions are very useful for a better view of the anatomic relationships with the other important structures in their treatment as the inferior dental nerve and the teeth. We present the features of each lesion and the differential diagnosis between the lesions: epithelial cysts odontogenic and non odontogenic, inflammatory as radicular cysts, and non epithelial as the aneurismal bone cyst, tumoral lesions as ameloblastoma, fibrous dysplasia, etc. Imaging findings OR Procedure details Maxillary and mandibular cyst classification: Odontogenic Inflammatory (radicular cyst or apical) Not inflammatory or developmental Non odontogenic from other epithelial remains. a)cyst of the nasopalatine duct (incisive canal): hard (bone compromise) (middle palatine cyst) b)nasolabial cyst (nasoalveolar): soft Inflammatory odontogenic cysts Page 2 of 28
Radicular cyst (50-55%), located: Apical Lateral (The infection goes through the lateral ducts) Residual cyst within the maxillary or mandibular foramen after exodontia. Paradental cyst Inflammatory follicular cyst: inflammation of the dental follicle of a permanent tooth after the inflammation of the epithelium of a temporary tooth. Radicular cyst: 50-75% of all the maxillary cysts. Ethiology: Apical granuloma (not necessarily will become a cyst) It activates the epithelium of Malassez remains and it forms a hole covered by epithelium and with variable content. Pathogenesis Increase of the luminal osmotic pressure (elimination of proteins and epithelial remains to the lumen), enters fluid, and the hole expands. Molecules with the potential of bone resorption Il-1, THF-a, prostaglandins, MMP (matrix metalloproteinase) Most frequent location Maxilla anterior>posterior Mandible posterior>anterior rd th Age :3 to 7 decades (very infrequent in children) Clinical symptoms Asymptomatic unless infected or reaches a great size. It expands the maxillary bone. Radiology Fig 1 Page 3 of 28
Translucent cavity Circumscribed With cortical bone that extends to the alveolar cortical of the tooth. When the limits are not well circumscribed it is because of infection, fast growth, the bone cannot react and form a new cortical. If the radicular cyst stays after exodontia it becomes a residual cyst. Complications It is lateral it can displace. It can cause bone or root resorption It can move the adjacent teeth. We cannor distinguish if an apical lesion is a granuloma or a cyst. It is said that if it diameter is greater than 1 cm it is a radicular cyst. It can only be determined by histology. Residual cyst Radicular cyst that remains within the bone when the tooth is removed. Features similar to radicular cyst. After removing it, the bone accumulates fluid, fibrous tissue and then it becomes a scar. Radiography: Fig 2 With the passing of time it becomes dense in the center. Paradental Cyst Origin: Inflammatory Associated to a vestibular projection of the enamel and partially erupted teeth. Radiology Translucent Circumscribed Unilocular Page 4 of 28
Location Distal or vestibular to a partially erupted third molar (18, 28, 38, 48). Inflammatory follicular cyst Inflammation of the inferior premolar follicle (within the bone thickness) associated to a temporary molar treated with endodontia. Age: Fist decade (8-12 years old). Features: More frequently in the inferior premolar More frequently on the left side Mandibular area (more frequently in 2 nd left temporary molar) It expands the vestibular bone and causes a facial asymmetry. The permanent tooth can remain locked within the cystic cavity. Identical features as the inflammatory cyst. Cyst wall with different stages of chronic inflammation. Non inflammatory odontogenic cysts Dentigerous or follicular cyst (Fig 3-8) Eruptive, a variant of dentigerous cyst (Fig 9-12) Keratocyst Gingival (or alveolar) cyst of the newborn Gingival cyst of the adult Periodontal lateral cyst Calcifying odontogenic cyst Glandular odontogenic cyst Follicular or dentigerous cyst Page 5 of 28
Cystic cavity that surrounds teeth within the bone. The cyst wall is joined to the tooth in the amelocementary limit (neck of the tooth). The most frequent The tooth and the cyst must be within the bone Location More frequently in the third inferior molar and superior canine (teeth that usually get included)) Age: 10-30 years old Gender 1'6:1 M: F Asymptomatic Radiology Absence of the tooth in the physical examination so an X-ray is performed Radiolucent cavity Clear limits Unilocular Variable degree of cortical surrounding Unspecific image It can destroy roots and displace adjacent teeth. Differential diagnosis with a thickened pericoronal sac: To be a cyst it has to have more than 3 mm of diameter. Types according to location: Central: surrounds the tooth (corona) Lateral: lateral to the tooth Circumferential: surrounds the whole tooth It can becomes an Ameloblastoma (odontogenic tumor) Page 6 of 28
Squamous cell carcinoma (if it becomes malignant, very infrequent) Mucoeoidermoid carcinoma (within the bone) Keratocyst 10-20% of developmental odontogenic cysts Two age peaks: 20-30 years and 50-60 years old Mandible 60-80% (posterior body, ramus) If it originates in an anterior tooth it is called primordial cyst. High recurrence rate 2-5, 62% Radiolucent cavity Clear limits More frequently unilocular, but it can be multilocular Location Posterior in the ramus Instead of the tooth Surrounding the crown simulating a dentigerous cyst. Between two teeth simulating a lateral periodontal cyst. Nasopalatine cyst Fig 13 and 14 They originate between the fourth and sixth decades of life They cause a divergence between the central superior incisive. Asymptomatic or painful if they become infected Radiology Radiolucent Conspicous Unilocular Page 7 of 28
Pseudocystic lesions of the jaws Not covered by epithelium Aneurysmal bone cyst Simple bone cyst Aneurysmal bone cyst Cavities with blood inside More frequent in people younger than 30 years old and women Usually in the molar area They have a rapid growth, they can be painful, with expansion of the inner bone and loss of cortical bone. Clear limits, uni or multilocular and expansive Differential diagnosis with keratocysts (usually not expansive) and with giant cell granuloma (without blood content) 50% recurrence rate after treatment with curettage Simple bone cyst Second decade, infrequent after 25 years old They usually are radiolucent lesions, with clear limits, and unilocular. The projections surrounding the tooth roots are characteristic. Differential diagnosis with keratocysts and ameloblastomas. Other cystic-like lesions Ameloblastoma Fibrous dysplasia Ameloblastoma Figs 15 to 22 Epithelial neoplasia: benign epithelial neoplasm. Age: More frequent between the third and fifth decades Page 8 of 28
Symptoms Slow growing painless mass Location Rami and posterior body of the jaw (80%) Radiological findings Radiologically well defined 1.-Radiolucent well defined masses, unilocular, with cortical and well differentiated (associated to the crown of the erupted or impacted teeth. Differential diagnosis Keratocyst Dentigerous cyst Undistinguishable by X-rays 2.- Multilocular masses with septa inside, honeycombing or bubble of soap pattern Differential diagnosis Big keratocysts CT Cystic areas of low attenuation with isodense solid areas inside. Fibrous dysplasia Figs 23 to 26 Common bone disease characterized by an undifferentiation of the bone forming mesenchyme More frequent in the maxilla that the in the mandible Symptoms Increase in size of the jaw that interferes with their functions or disfigures Radiology Scalloped appearance, ground glass pattern with cortical thinning, with cystic areas because of the hemorrhage. Page 9 of 28
Images for this section: Fig. 1: Panoramic radiography that shows a radicular cyst in the inferior right molar Fig. 2: Panoramic radiography that shows a Residual Cyst adjacent to the root of the first left inferior molar (36) with a previously removed crown Fig. 3: Odontogenic cyst of the left inferior third molar (38). MDCT coronal reconstruction. Page 10 of 28
Fig. 4: Odontogenic cyst in the left inferior third molar (38).The cyst surrounds the tooth s crown. The diagnosis of keratocyst is histopathological in most cases. MDCT coronal reconstruction. Page 11 of 28
Fig. 5: Odontogenic cyst of 38 tooth in contact with the left inferior dental nerve that can cause prpblems in the exodontia. MDCT Curve reconstruction, in a similar plane to panoramic view radiography. Fig. 6: Odontogenic cyst. MDCT coronal reconstruction Fig. 7: Odontogenic cyst. MDCT in a coronal plane. Page 12 of 28
Fig. 8: Odontogenic cyst. MDCT Curve reconstruction Fig. 9: Cyst surrounding a non erupted canine. Panoramic view radiography Fig. 10: Cyst surrounding a non erupted canine or included tooth. MDCT axial plane. Fig. 11: Canine inclusion tooth cyst. MDCT Coronal plane reconstruction Fig. 12: Canine inclusion tooth cyst of the mandible. MDCT Volume rendering image that shows how the canine erodes and surpasses the mandibular cortical and the crown emerges. Page 13 of 28
Fig. 13: Nasopalatine duct cyst. MDCT with a coronal plane reconstruction. Page 14 of 28
Fig. 14: Nasopalatine duct cyst. MDCT axial image Page 15 of 28
Fig. 15: Maxillary ameloblastoma. Panoramic view radiography. Page 16 of 28
Fig. 16: Left maxillar ameloblastoma that displaces the teeth, crosses the middle line with a very thin cortical bone almost absent. MDCT. Axial plane. Page 17 of 28
Fig. 17: Ameloblastoma maxilar izdo que desplaza piezas dentarias, cruza la línea media con una cortical muy fina prácticamente ausente. TCMD Plano axial. Left maxillar ameloblastoma that displaces the teeth, crosses the middle line with a very thin cortical bone almost absent. MDCT. Axial plane. Page 18 of 28
Fig. 18: Ameloblastoma maxilar izdo que desplaza piezas dentarias, cruza la línea media con una cortical muy fina prácticamente ausente. TCMD Plano axial. Left maxillar ameloblastoma that displaces the teeth, crossed the middle line with a very thin cortical bone, almost absent. MDCT. Axial plane. Page 19 of 28
Fig. 19: Right mandibular body amelobastoma. Panoramic view radiography. Page 20 of 28
Fig. 20: Giant ameloblastoma of the right mandibular body, filled with content with areas of higher density typical of this pathololgy. MDCT. Axial plane. Page 21 of 28
Fig. 21: Giant ameloblastoma of the right mandibular body, filled with content with areas of higher density typical of this pathology. MDCT. MPR curve reconstruction Page 22 of 28
Fig. 22: Giant ameloblastoma of the right mandibular body, filled with content with areas of higher density typical of this pathology. MDCT. MPR oblique sagital reconstruction Page 23 of 28
Fig. 23: Monostotic fibrosus dysplasia of the right mandibular ramus that has caused teeth to fall. Panoramic view radiography. Page 24 of 28
Fig. 24: Monostotic fibrous dysplasia of the right mandibular ramus, that shows an increase of size with an heterogenous appearance with ground glass attenuation and cystic areas within. MDCT with a coronal reconstruction. Page 25 of 28
Fig. 25: Monostotic fibrous dysplasia of the right mandibular ramus. MDCT right lateral volume rendering image. Page 26 of 28
Fig. 26: Displasia Fibrosa monostótica de la rama mandibular derecha. TCMD Imagen de "Volume Rendering" oblicua frontal dcha Monostotic fibrous dysplasia of the right mandibular ramus. MDCT. Oblique frontal volume rendering image Page 27 of 28
Conclusion The study with panoramic radiography and CT of cystic lesions of the jaws allow us to know their features and to establish a better differential diagnosis that identifies the lesions, their relationship with surrounding structures and help to plan their treatment, that usually consist of surgical excision and pathological studies because of the similarity between them. References 1.- Cyst and cystic lesions of the Mandible:Clinical and Radiologic-Histopathologic Review Robert J. Scholl MD, Helen M Kellet MD, DAvid P Neumann MD, Alan G Lurie, DDS PhD Radiographics 1999; 19: 1107-1124 2.-Imaging of cysts and odontogenic tumors of the jaw.weber AL. Radiological Clinics of North America 1933, 31:101120 Personal Information Page 28 of 28