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Zebra XXII, Part 2.
JOURNAL OF ENDODONTICS Copyright © 2001 by The American Association of Endodontists
Printed in U.S.A. VOL. 27, NO. 11, NOVEMBER 2001
ZEBRA HUNT Zebra XXII, Part 2. Giovanna Orsini, Massimiliano Fioroni, Corrado Rubini, and Adriano Piattelli
In the last issue of the Journal a case of a 46-yr-old female patient with several multiple radiolucent lesions located at the apex of several teeth was presented. Intraoral periapical radiographs (Figs. 1 and 2) showed that these lesions presented sharp, distinct margins. These lesions were painless. Two fibro-osseous lesions were offered for your differential diagnosis: cemento-osseous dysplasia (COD) and cemento-ossifying fibroma (COF). The importance of a correct diagnosis was stressed because of the completely different clinical behavior of the previously described conditions. COD represents a spectrum of nonneoplastic fibro-osseous lesions usually confined to the tooth-bearing areas of the jaws. COD represents a single disease process and is present in several forms. The term periapical denotes that lesions are located in close association with the roots of teeth; multiple lesions are often present and are usually asymptomatic and discovered in routine X-rays. Individual lesions are rarely ⬎1.0 cm and most are ⬍0.5 cm. The uniqueness of the COD location implicates the surrounding periodontal soft tissues as the origin. Within the fibrous tissue of the periodontal ligament it is possible to find progenitor cells that form
FIG 2. Intraoral periapical radiography of tooth #20, tooth #21, and tooth #22.
both bone and cementum, and these features are very similar to the microscopic aspects observed in COD. In some instances, COD may be found in areas where teeth have been surgically removed, where no periodontal ligament is present, and in other cases cementum-like calcifications are found outside of tooth-bearing areas, including the long bones of the extremities. COD seems not to have an inflammatory etiology; the inflammatory component, when present, seems to occur only when the dense sclerotic calcifications perforate the oral mucosa letting oral bacteria gain entry to underlying bone. COD seems to be a reactive self-limiting lesion. The marked predilection for Black women also goes against an inflammatory origin. Microscopically COD is characterized by a loosely cellular fibrous connective tissue with many small vascular spaces; calcified material, which may range from droplet or psammomatoid-like mineralization to trabecular areas, is present. The ratio of fibrous tissue to mineralized material may vary. In initially fibroblastic lesions it is possible over the years to find increasing degrees of calcification. As in ossifying fibroma, the mineralized material is a mixture of woven bone, lamellar bone, and cementum-like particles. Despite the fact that it is a well-recognized condition, patients sometimes undergo endodontic treatment due to an erroneous diagnosis of periapical granuloma or cyst. In most cases it is difficult or impossible to differentiate from a microscopic point of view, COD from COF, which is a neoplasm
FIG 1. Intraoral periapical radiography showing the lesion of tooth #28 and tooth #29. 706
Vol. 27, No. 11, November 2001
requiring surgical treatment, and additional clinical and especially radiographic correlations are required. COF occurs in patients an average of 10 yr younger than patients with COD. COD is not encapsulated and has continuity with the surrounding bone, whereas COF is an encapsulated, well-circumscribed lesion. Moreover COF is likely to be large (with a mean size of the lesions of 3.8 cm against 1.8 cm for COD) to cause more frequent symptoms (jaw expansion in ⬎50% of cases) and to be more radiolucent, whereas COD showed an irregularly mixed radiopacity in 69% of the cases. COF typically has a sclerotic, well-defined margin, whereas LCOD presents irregular or ill-defined borders. In addition COF is found mostly in the mandibular molar region and may not have a direct relationship to the roots of teeth. Microscopically COF exhibits a sharp interface with the neighboring bone, whereas on the contrary in COD surrounding jawbone penetrates into the lesions over some distance. At surgery the lesions in COD are hemorrhagic, gritty, and adherent to surrounding bone. The gross appearance of multiple hemorrhagic fragments is of diagnostic significance. No intervention is required in COD. A periodic follow-up is however recommended because of the fact that sometimes cases are observed progressing into florid osseous dysplasia. Only in cases of COD where it is possible to find isolated lesions in less typical clinicalradiological situations is a biopsy indicated to rule out a more important pathological process.
DISCUSSION Under local anesthesia, after elevation of a mucoperiosteal flap, a biopsy of the periapical lesion of tooth #20 was undertaken. Microscopic examination showed the presence of a stromal tissue where it was possible to find islands of metaplastic bone tissue, and foci of cementum-like material (Fig. 3). The definitive diagnosis was periapical COD. The patient underwent no further treatment. In conclusion clinical data other than radiographs are usually of little value in the differential diagnosis of maxillo-facial fibro-
Zebra Hunt
707
FIG 3. It is possible to observe a stromal tissue with islands of metaplastic bone tissue (b) and foci of cementum-like material (c). H&E ⫻100.
osseous lesions, and of great importance are adequate biopsy specimens that should contain lesional as well as surrounding tissue and technically optimal radiographs. The differential diagnosis between self-limiting and neoplastic lesions can be made reliably on histological grounds. Moreover it has been shown that there is also a good agreement between radiography and microscopic results that concerns separation or blending with surrounding bone. It must also be considered that overlapping histological features of fibro-osseous lesions and atypical features of individual lesions often may make definitive diagnosis difficult. Dr. Orsini is a research fellow, Dental School, University of Chieti, Chieti, Italy. Dr. Fioroni is a research fellow, Dental School, University of Ancona, Ancona, Italy. Dr. Rubini is a researcher, Institute of Pathologic Anatomy and Histopathology, University of Ancona, Ancona, Italy. Dr. Piattelli is a professor, Department of Oral Medicine and Pathology, Dental School, University of Chieti, Chieti, Italy. He is also honorary senior lecturer, Eastman Dental Institute for Oral Health Care Sciences, London, UK. Address requests for reprints to Professor Adriano Piattelli, Via F. Sciucchi 63, 66100 Chieti, Italy.
Printed in U.S.A. VOL. 27, NO. 11, NOVEMBER 2001
ZEBRA HUNT Zebra XXII, Part 2. Giovanna Orsini, Massimiliano Fioroni, Corrado Rubini, and Adriano Piattelli
In the last issue of the Journal a case of a 46-yr-old female patient with several multiple radiolucent lesions located at the apex of several teeth was presented. Intraoral periapical radiographs (Figs. 1 and 2) showed that these lesions presented sharp, distinct margins. These lesions were painless. Two fibro-osseous lesions were offered for your differential diagnosis: cemento-osseous dysplasia (COD) and cemento-ossifying fibroma (COF). The importance of a correct diagnosis was stressed because of the completely different clinical behavior of the previously described conditions. COD represents a spectrum of nonneoplastic fibro-osseous lesions usually confined to the tooth-bearing areas of the jaws. COD represents a single disease process and is present in several forms. The term periapical denotes that lesions are located in close association with the roots of teeth; multiple lesions are often present and are usually asymptomatic and discovered in routine X-rays. Individual lesions are rarely ⬎1.0 cm and most are ⬍0.5 cm. The uniqueness of the COD location implicates the surrounding periodontal soft tissues as the origin. Within the fibrous tissue of the periodontal ligament it is possible to find progenitor cells that form
FIG 2. Intraoral periapical radiography of tooth #20, tooth #21, and tooth #22.
both bone and cementum, and these features are very similar to the microscopic aspects observed in COD. In some instances, COD may be found in areas where teeth have been surgically removed, where no periodontal ligament is present, and in other cases cementum-like calcifications are found outside of tooth-bearing areas, including the long bones of the extremities. COD seems not to have an inflammatory etiology; the inflammatory component, when present, seems to occur only when the dense sclerotic calcifications perforate the oral mucosa letting oral bacteria gain entry to underlying bone. COD seems to be a reactive self-limiting lesion. The marked predilection for Black women also goes against an inflammatory origin. Microscopically COD is characterized by a loosely cellular fibrous connective tissue with many small vascular spaces; calcified material, which may range from droplet or psammomatoid-like mineralization to trabecular areas, is present. The ratio of fibrous tissue to mineralized material may vary. In initially fibroblastic lesions it is possible over the years to find increasing degrees of calcification. As in ossifying fibroma, the mineralized material is a mixture of woven bone, lamellar bone, and cementum-like particles. Despite the fact that it is a well-recognized condition, patients sometimes undergo endodontic treatment due to an erroneous diagnosis of periapical granuloma or cyst. In most cases it is difficult or impossible to differentiate from a microscopic point of view, COD from COF, which is a neoplasm
FIG 1. Intraoral periapical radiography showing the lesion of tooth #28 and tooth #29. 706
Vol. 27, No. 11, November 2001
requiring surgical treatment, and additional clinical and especially radiographic correlations are required. COF occurs in patients an average of 10 yr younger than patients with COD. COD is not encapsulated and has continuity with the surrounding bone, whereas COF is an encapsulated, well-circumscribed lesion. Moreover COF is likely to be large (with a mean size of the lesions of 3.8 cm against 1.8 cm for COD) to cause more frequent symptoms (jaw expansion in ⬎50% of cases) and to be more radiolucent, whereas COD showed an irregularly mixed radiopacity in 69% of the cases. COF typically has a sclerotic, well-defined margin, whereas LCOD presents irregular or ill-defined borders. In addition COF is found mostly in the mandibular molar region and may not have a direct relationship to the roots of teeth. Microscopically COF exhibits a sharp interface with the neighboring bone, whereas on the contrary in COD surrounding jawbone penetrates into the lesions over some distance. At surgery the lesions in COD are hemorrhagic, gritty, and adherent to surrounding bone. The gross appearance of multiple hemorrhagic fragments is of diagnostic significance. No intervention is required in COD. A periodic follow-up is however recommended because of the fact that sometimes cases are observed progressing into florid osseous dysplasia. Only in cases of COD where it is possible to find isolated lesions in less typical clinicalradiological situations is a biopsy indicated to rule out a more important pathological process.
DISCUSSION Under local anesthesia, after elevation of a mucoperiosteal flap, a biopsy of the periapical lesion of tooth #20 was undertaken. Microscopic examination showed the presence of a stromal tissue where it was possible to find islands of metaplastic bone tissue, and foci of cementum-like material (Fig. 3). The definitive diagnosis was periapical COD. The patient underwent no further treatment. In conclusion clinical data other than radiographs are usually of little value in the differential diagnosis of maxillo-facial fibro-
Zebra Hunt
707
FIG 3. It is possible to observe a stromal tissue with islands of metaplastic bone tissue (b) and foci of cementum-like material (c). H&E ⫻100.
osseous lesions, and of great importance are adequate biopsy specimens that should contain lesional as well as surrounding tissue and technically optimal radiographs. The differential diagnosis between self-limiting and neoplastic lesions can be made reliably on histological grounds. Moreover it has been shown that there is also a good agreement between radiography and microscopic results that concerns separation or blending with surrounding bone. It must also be considered that overlapping histological features of fibro-osseous lesions and atypical features of individual lesions often may make definitive diagnosis difficult. Dr. Orsini is a research fellow, Dental School, University of Chieti, Chieti, Italy. Dr. Fioroni is a research fellow, Dental School, University of Ancona, Ancona, Italy. Dr. Rubini is a researcher, Institute of Pathologic Anatomy and Histopathology, University of Ancona, Ancona, Italy. Dr. Piattelli is a professor, Department of Oral Medicine and Pathology, Dental School, University of Chieti, Chieti, Italy. He is also honorary senior lecturer, Eastman Dental Institute for Oral Health Care Sciences, London, UK. Address requests for reprints to Professor Adriano Piattelli, Via F. Sciucchi 63, 66100 Chieti, Italy.