Radiologic considerations in evaluation of radiolucent lesions of the mandible

Careful attention to technique is of utmost importance in instances in which clinical evidence indicates that the osteolytic or osteogenic margins of a lesion may extend beyond those visible on a conventional radiograph. Procedures such as radionuclide scans should be used to establish the appropriate boundaries for surgical resection in such instances. Although early surgical intervention will usually lead to a definitive histopathologic diagnosis, there is some risk that manipulation will either compromise the validity of later radiological procedure or extend the disease by local dissemination or blood-borne metastases. Appropriate radiologic evaluation of lytic lesions of the mandible can provide a maximum amount of information so that surgical resection of the lesion will be complete, and the possibility of recurrence will be reduced.

[Follow-up of 5 cases of mandibular adamantinoma treated by osteotomy and mixed grafts]

The examination after fifteen years of five cases of mandibular adamantinoma treated with an operation performed in two stages (graft of metallic prosthesis and osseous autograft) has confirmed the success of this surgical method. In particular from the clinical and radiological examination it turns out that the essential requisites for a therapeutical success have been respected: the anatomical restoration and the aesthetical and function rehabilitation.

The maxillary ameloblastoma: an analysis of 24 cases

Twenty-four cases of maxillary ameloblastoma from the files of the dental and oral division of the Armed Forces Institute of Pathology and the US Army Institute of Dental Research were reviewed. Clinical findings showed an average age of 45.6 years, a male-to-female ratio of 2.4:1, and an equal racial distribution between whites and blacks. Eighty-eight percent of the tumors occurred distal to the maxillary canine. A slowly enlarging mass was the primary clinical sign in more than 90% of the cases. Recurrences were seen in eight of the 16 cases on which follow-up information was received. The majority of the tumors had a mixed follicular histologic pattern. Therapy should consist of either surgical block excision or hemimaxillectomy. The surgeon must carefully weigh the potential danger of the neoplasm against the deformity and disability caused by the surgical procedure.

Computerized tomography in oral and maxillofacial surgery

Computerized tomography has revolutionized the art of diagnosis by noninvasive techniques. Until recently, its use in oral and maxillofacial surgery has been limited. Basic principles include the production of a two-dimensional image representing an anatomically accurate slice of tissue. Advantages of computerized tomography are lack of image superimposition, preservation of detail of soft tissue, enhancement of vascular tumors, selective enlargement of areas of interest, tomographic capability, and the future possibility of the production of three-dimensional images. However, the presence of any metallic restoration produces artifacts, which limits the use of computerized tomography to areas excluding the dentition where restorations are present. Clinical application at our institution has been to use computerized tomography in the differential diagnosis of infections, midfacial trauma, vascular lesions, and lesions involving the mandibular ramus and maxilla.

Dentigerous cyst with mural ameloblastoma

A case of a 14-year-old black girl with a lesion that appeared to be a dentigerous cyst is presented. Radiographic appearance, findings of a bone scan and biopsy by aspiration are discussed. Histologic findings showed that the lesion was an ameloblastoma that is believed to have arisen from the dentigerous cyst wall.

Immediate mandibular reconstruction after resection using a modified Kirschner wire splint

The use of a modified Kirschner wire splint is described and our experience with this procedure in 25 patients is reviewed. The splint is intended to be a temporary method of maintaining bone fragments in the correct position while intraoral seal is established. After sufficient healing has occurred, a final reconstruction is done by bone grafting.

Adamantinoma tibiae

A case with characteristic roentgenographic and microscopic findings of adamantinoma tibiae is reported. Knee disarticulation with early ambulation is the treatment of choice and was performed on this patient. Limb ablation followed by Unna Paste Bandage to prevent oedema and permit early prosthetic fitting facilitates rehabilitation. The 1 year follow-up showed excellent prosthetic function and no evidence of residual tumour.

["Adamantinoma" of the tibia and reactive bone changes (author's transl)]

A case of "adamantinoma" of the tibia is reported. 10 years ago a giant tumor with fibrous dysplasia had been diagnosed in a biopsy taken from the same site of cystic bone changes. These findings may occur as reaction in the periphery of "adamantinomas" of long bones. By this experience the importance was emphasized, to obtain tissue from the center portion of the tumor to include the typical epithelial islets pathognomonic for "adamantinomas", which in our case, were found only 10 years after the first operation. Our patient was treated by curetting and filling of the defect with bony splinters. At this time, 8 months after surgery, he is without complaints and in full use of his diseased leg.

Ameloblastomas

Ameloblastomas are slow-growing, destuctive lesions of the jaws. They have a wide age distribution and occur in both sexes. In considering the treatment of these lesions, one must take into consideration the patient's age, the patient's concern for his (her) functional, social and aesthetic requirements. It is not unreasonable to aim at a conservative approach first, then radical surgery when the lesion recurs. Small lesions can be treated by local block excision or curettage. For large lesions and recurrences in the mandible, jaw resection and immediate bone graft is indicated. In the author's experience, split iliac crest graft gives the best clinical result.

[Roentgenological differentiation characteristics in odontomata of the jaw (author's transl)]

Odontomata of the jaw are relatively rare. They can be easily diagnosed by means of special x-ray techniques provided they are composite odontomata. Difficulties are created by ameloblastofibromes and complex odontomata. Complete excochleation predominates in surgical therapy, first importance being given to sparing vital neighbouring teeth and vasomotor nerve bundles.

Treatment of the ameloblastoma: a controversy

Treatment of the ameloblastoma should be re-evaluated based on microscopic behavior. We suggest that conservative therapy is the initial treatment of choice. Although medullary bone is invaded by tumor cells, compact bone only is eroded. Therefore, treatment should be directed at removal of involved medullary bone, leaving as much medial and lateral cortical plates and inferior mandibular border as possible. Four patients with ameloblastoma treated conservatively are presented. Evaluation from 21 months to seven years after initial therapy revealed marked bone regeneration. Three of the four had smaller lesions remaining, requiring less radical surgery than would normally have been performed initially. No tumor was evident on rebiopsy of the fourth patient. Conservative treatment and proper follow-up were acceptable methods of initial treatment in our cases.

Conservative surgical treatment of mandibular ameloblastomas

The results of a follow-up investigation of 12 patients with ameloblastomas of the mandible, treated by conservative surgical means, are presented. The age of the patients at the time of operation ranged from 8 to 77 years, the average age being 41 years. Seven of the tumors had a unilocular and five a multilocular appearance. The operation technique varied somewhat with the individual case. An attempt was made in all cases to remove the tumor in toto. In cases with multilocular appearance or where the tumor was in connection with the surface epithelium, a resection of the roof of the lesion was made. Microscopic examination of the tumors revealed that they all could be classified as plexiform or folicular but with various degrees of differentiation. Seven of the patients were observed for more than 5 years, the others for less. Three instances of recurrence were diagnosed and were in all cases less than 1 cm in diameter. The recurrences were found 1, 3, and 20 years after the primary treatment. Although the number of patients and the observation period are limited, the preliminary results seem encouraging.

[Different roentgenographic structures in ameloblastoma of jawbone (author's transl)]

The ameloblastoma is a benign, but locally invasively growing tumor with different radiographic structures. These structures may well be explained by typical development of the tumor. Occasionally differential diagnosis appears difficult. Various roentgenographic techniques do facilitate surgical planning if the diagnosis is confirmed microscopically.

Scintigraphy of human autologous rib transplants to a partially resected mandible

The 99Tcm-DP accumulation in split ribs grafted to six cases of partially resected mandibles was examined by scintigraphy at different time intervals after operations and found to be higher than in normal facial bones. The accumulation was highest around one month after the grafting procedure, and later decreasing. Differences between bone chips, split ribs and unsplit ribs are described. Bone scintigraphy is assumed to be of value in following the metabolic state of bone grafts.

Unicystic ameloblastoma: a prognostically distinct entity

The occurrence of unicystic ameloblastoma has been studied in 20 patients presenting with unilocular cystic lesions whose clinical, radiographic and gross features were those on non-neoplastic cysts. In the majority of these, the lesion mimicked dentigerous cyst. The rate of recurrence for this group of lesions as determined by long term follow-up observation available for the majority of patients was distinctly lower than that associated with multicystic character of the lesion throughout its course, is indicative of a much less aggressive variety of neoplasm. The adequacy of simple enucleation as a modality of treatment in the majority of patients with this type of lesion is suggested. It was not possible to answer the question whether or not the ameloblastoma began in antecedent non-neoplastic cyst.

Radiology of multiloculated fibrous dysplasia of the jaws

Three cases of multiloculated lesion of the jaw (two in the mandible and one in the maxillar) closely mimicking ameloblastoma are described. Histology showed all three to be fibrous dysplasia. Against a diagnosis of ameloblastoma were (1) the relative fuzziness of the margins of the loculi and septae; (2) the mineralization of the matrix which gave a ground-glass background instead of the distinct radiolucency seen in ameloblastoma; and (3) the non-resorption of the dental root apices within the lesion.

Ameloblastoma of the maxilla

Ameloblastomas of the maxilla are uncommon tumors of dental origin that slowly invade and destroy local tissues. A patient with extensive ameloblastoma of the maxilla presenting as a nasal mass is reported, and the clinical features, histopathology, and current treatment of this lesion are discussed. With involvement of the maxillary alveolar ridge and sinus, only radical en bloc resection can be considered appropriate treatment.

A case report of keratoameloblastoma

In the "WHO histological typing of odontogenic tumors, jaw cysts and allied lesions", the authors recognize five distinct histologic types of ameloblastoma. A further histologic variant, the keratoameloblastoma, was first described by PINDBORG. A second case of a keratoameloblastoma is reported. This lesion occurred in the maxilla of a 28-year-old Caucasian male.

[Ameloblastoma formation in an extensive follicular cyst]

A case of an unusual extensive dentigerous cyst of the mandible with ameloblastic formations in the cyst wall is presented. The tumor was totally enucleated in a two-step conservative surgical prosedure over 14 months, whereby the continuity of the mandible was preserved. The patient has been followed for two years. There has been a complete bone regeneration and no recurrence of the tumor. The importance of biopsy of odontogenic cysts associated with mandibular third molars is stressed.

Root resorption by ameloblastomas and cysts of the jaws

Radiographs of 122 cases of a series of nonmalignant simple jaw cysts and ameloblastomas were examined and the frequency of resorption of adjacent tooth roots compared. The ameloblastomas proved to have a root resorptive potential far greater than the cystic lesions considered. Certain statistically significant differences were observed in the root resorption related to the cystic lesions. The dentigerous cyst showed a tendency to resorb roots (55%), whereas in this study no resorption was observed in primordial cysts. These differences may aid the clinician in the preoperative differential diagnosis. It is suggested that the capacity of the dentigerous cyst for root resorption may be the result of its origin from the dental follicle, which is associated with resorption of the roots of primary teeth during normal tooth succession.

Radiologic and pathologic diagnosis of tumors of the jaws

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Postoperative sequelae of cryosurgery

Cryosurgery is a proved method for treatment of neoplasms of the soft and hard tissues of the oral cavity. It is not free, however, from postoperative complications. Delayed healing and extensive scarring are common occurrences. Significant functional and esthetic impairment, although uncommon, can result. Exposure of lingual mandibular bone can interfere with prosthetic replacement. Postfreezing evaluation of cervical nodes in patients treated for oral cancers can be complicated by persistent lymphadenopathy. Cryosurgery of irradiated bone or overlying tissue can result in osteoradionecrosis. Although the possibility of these complications should not be a major deterrent when it is felt that cryosurgery is the preferred method for treating a malignancy, the complications deserve careful consideration in the management of benign lesions.

Radiologic features of ameloblastoma in Nigerians

Radiology plays an important role in preoperative diagnosis and postoperative assessment of ameloblastoma. The postoperative appearances, including complications as well as radiologic features of recurrence, are discussed. The differential diagnosis of the unilocular lesion is difficult, and particularly noteworthy are the five cases of histologically proven adamantinoma whose radiographic appearance closely mimicked dentigerous cyst.

Simple bone cyst. Report of two cases

Two cases of simple bone cyst are presented. The first is unusual because of its radiologic appearance simulating ameloblastoma and its prolonged healing time, requiring surgical intervention on several occasions. The second is presented because of the occurrence of bilateral cysts, of which there are only eight other reported cases. It is postulated that the first case might represent a single large simple bone cyst that had several chambers with tenuous connections or that it might be an example of multiple simple bone cysts in close proximity.

Ultrastructure of an odontogenic myxoma

The ultrastructural findings in a case of odontogenic myxoma are described. The main cell type was characterized by several cytoplasmic processes, intracytoplasmic fibrils, numerous glycogen particles, and salient Golgi complexes. A few mitochondria and a scarce endoplasmic reticulum was noted. The matrix consisted of numerous granules with fibrillar projections, collagen bundles, and smaller fibers. The over-all ultrastructural features of this tumor were similar to those described in the human cardiac myxoma and in Wharton's jelly and could be clearly differentiated from the fine structural characteristics of other connective tissue tumors.

Ameloblastoma of the upper jaw

A clinical study was made of three cases of Ameloblastoma (Adamantinoma) of the maxilla. One case presented with oro-antral fistula following extraction of a molar tooth. Extensive bone destruction and involvement of ethmoidal air sinuses and nasal cavity was seen in one of the patients. At times histological diagnosis can be difficult; therefore, accurate diagnosis should be obtained by an experienced histopathologist. Partial maxillectomy with a wide margin of healthy bone should be the choice of treatment in the majority of cases. There tumours are sensitive to deep-X-ray to a varying degree. One should consider radiotherapy post-operatively if growth has been excised inadequately. Radiotherapy may be helpful when surgery is contraindicated.

Adamantinoma of long bones. A clinicopathological study of fourteen cases with vascular origin suggested

Adamantinoma of long bones is a rare primary bone tumor. Approximately 100 cases have been reported in the literature. In the fourteen cases we studied in detail the ages of the patients ranged from thirteen to sixty-seven years and there were as many males as females. Twelve of the lesions were located in the tibia and two, in the humerus. The roentgenographic findings were sharply defined eccentric lobular lesions in the diaphysis. Some of the lesions were lytic and coarsely trabecular with a honeycomb appearance occasionally associated with periosteal new-bone formation. A sawtooth area of cortical-bone loss was found to be characteristic of this lesion. A microscopic finding is presented to support the theory of angioblastic origin of this tumor. The most successful treatment was amputation. Less often en bloc excision succeeded. Metastases to other bones, regional lymph nodes, and the lung were recorded.