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Salivary gland tumors of the mandible.

Primary central salivary gland carcinomas of the mandible are uncommon neoplasms. Consequently, their proper diagnosis is often in doubt. We retrospectively studied the cases of 16 patients treated at The University of Texas M. D. Anderson Cancer Center and the Institut Gustave Roussy from 1950 to 1990. Patients ranged in age from 24 to 76 years (mean, 51 years). Nine patients were women and seven were men. Each case involved either the angle or the posterior body of the mandible. Swelling, pain, and trismus were the most frequent complaints. For all patients, radiography revealed a cystic defect resembling an osteolytic odontogenic lesion or metastasis. Five histologic types of carcinoma were diagnosed: seven cases of mucoepidermoid carcinoma (five low-grade and two high-grade), four cases of adenoid cystic carcinoma, two cases of adenocarcinoma, two cases of acinic-cell carcinoma, and one case of epithelial-myoepithelial carcinoma. All patients were treated with wide surgical excision. Eight patients received postoperative irradiation. Five patients with low-grade mucoepidermoid carcinoma, two with acinic-cell carcinoma, and one with epithelial-myoepithelial carcinoma were free of disease 2 to 15 years after initial treatment (mean, 6.2 years). Two patients with adenoid cystic carcinoma are living with lung metastasis. The remaining six patients died of their carcinomas within 4 years after initial treatment. Because of their unique morphology and clinical behavior, these tumors should be distinguished from other intraosseous neoplasms of the mandible, including those with clear-cell patterns.

Adenocarcinoma↗

Clinician variability in characterizing mandible fractures.

PURPOSE: This study evaluated variability in the clinical parameters commonly used to characterize mandible fractures. PATIENTS AND METHODS: Inter-rater reliability of 18 oral and maxillofacial surgeons was assessed using radiographs of 22 cases of mandible fractures. Raters were asked to evaluate each case based on several parameters including number, location, and displacement of the individual fractures and severity of the composite injury. To evaluate intra-rater reliability, selected cases were reviewed at a second session by a subgroup of these surgeons. Tests of concordance used to quantify measurement reliability included the interclass correlation coefficient and multiple-rater kappa statistics. RESULTS: Inter-rater agreement on the number of constituent fractures ranged from excellent for simpler fractures to poor for complex gunshot injuries. Even within raters, the range of interclass correlation for complex injuries was only 0.33 to 0.42 between the 2 assessments. Clinicians appeared to be better at delineating coronoid, condyle, ramus, and angle fractures; symphyseal and canine region fractures had lower inter- and intrarater agreement. Tests of concordance showed moderate to excellent reliability when fracture displacements were expressed in millimeters, but only fair reliability when displacements were expressed as categories. Even when the clinicians concurred on displacement measurements, a large overlap was observed in their categorization of these displacements. Despite the differences in the assessment of individual parameters, the high intrarater reliability coefficient (0.78) indicated that the individual clinicians had a high internal consistency in their assignment of summary severity scores. Multiple regression analysis revealed the number of constituent fractures, the type of fracture, and amount of fracture displacement (millimeters) to be significant predictors of clinician ratings of injury severity. CONCLUSIONS: The clinician variability underscores the difficulties involved in trauma description and scoring. The study identifies some sources of clinician variability and emphasizes the need to standardize the characterization of mandible fractures by using explicit guidelines.

Adult↗

Salivary duct carcinoma in the mandible: report of a case with immunohistochemical studies.

Salivary duct carcinoma is rare. We describe a 56-year-old man who developed salivary duct carcinoma in the mandible 10 years after removal of the right second and third molars. The tumour originated in the retromolar gland or the ectopic minor salivary gland in the mandible. The panoramic radiograph showed a radiolucent, poorly circumscribed area about 40 x 30 mm in size and distal to the lower right first molar. This tooth, together with all neoplastic tissue, was removed, and histopathological examination showed it to be a salivary duct carcinoma in the mandible. On immunohistochemical staining, keratin antibodies stained the ductal structure, 1A4 antibody stained myoepithelial cells, but S-100 protein and vimentin were not seen. The patient was well and with no sign with recurrence 6 years postoperatively.

Actins↗

Lateral functional shift of the mandible: Part II. Effects on gene expression in condylar cartilage.

There is considerable evidence that proliferation and growth in the mandibular condylar cartilage (MCC) might be altered after a change in the postural position of the mandible. However, almost nothing is known about the molecular basis of this response. Using semiquantitative reverse-transcription polymerase chain reaction, we examined the expression of insulin-like growth factor-1 (Igf-1), fibroblast growth factor-2 (Fgf-2), and their receptors (Igf-1r, Fgfr1, Fgfr2, and Fgfr3) in the MCC of 28 day-old rats at 3, 7, and 14 days after placing intraoral appliances designed to produce a lateral functional shift of the mandible. This shift resulted in a transverse rotation of the mandible so that the condyle on the side away from the shift was distracted anteriorly (ie, protruded) from the glenoid fossa, while the contralateral condyle remained in place or moved slightly posteriorly (ie, nonprotruded). Gene expression for 5 of the 6 genes studied was significantly different (P <.05) between the protruded and the nonprotruded sides. In nearly every instance at the 3- and 7-day intervals, mRNA expression on the protruded side compared with age-matched controls was altered in the opposite direction from the nonprotruded side. Especially on the protruded side, the most pronounced differences from the control were evident at 3 and 7 days. In general, the changes in gene expression preceded the alterations in proliferative activity documented previously. These data suggest that alterations in the mRNA expression of Igf-1, Fgf-2, and their receptors might underlie in part changes in MCC proliferative activity after alteration in mandibular posture.

Animals↗

Melanotic neuroectodermal tumor of infancy in the mandible: report of a case.

A case of melanotic neuroectodermal tumor of infancy occurring in the mandible is described. The patient was a 1-month-old boy with a rapidly growing tumor of the mandible. Computed tomography showed 2 well-defined osteolytic lesions in the right mandible. Histopathologic diagnosis of a biopsy specimen was melanotic neuroectodermal tumor of infancy. The tumor was excised with removal of the surrounding bone, but 1(1/2) months later it recurred, and segmental mandibulectomy and reconstruction of the defect with a titanium miniplate was performed. Retrospectively, evidence of recurrence was noted on computed tomography taken on the tenth postoperative day. The recurrence was caused by incomplete removal of the tumor. Histopathologically, the tumor cells of the recurrent lesion were dispersed extensively in the bone marrow, and bone remodeling was active. The surgical procedure may have stimulated tumor cell proliferation and reactive bone formation. The patient was followed for 2 years with no evidence of recurrence or metastasis.

Humans↗

Primary non-Hodgkin's lymphoma of the mandible treated with radiotherapy, chemotherapy, and autologous peripheral blood stem cell transplantation.

Extranodal presentation in non-Hodgkin's lymphoma (NHL) is uncommon, and the mandible is very rarely involved. Primary NHL of the mandible, for the most part, has intermediate or high malignancy and has a much greater incidence of local recurrence compared with other sites of involvement. A 48-year-old Japanese man with NHL of the mandible received radiotherapy, followed by high-dose chemotherapy supported with peripheral blood stem cell transplantation (PBSCT). High-dose cyclophosphamide, Adriamycin, and vincristine were used for pretransplant conditioning. He achieved complete remission and has survived in continuous complete remission for more than 72 months to date. Marrow-ablative chemotherapy facilitated by PBSCT is thought to be useful as part of the primary therapy for patients with NHL who have poorer prognoses.

Antineoplastic Combined Chemotherapy Protocols↗

Foreign-body granuloma occurring in the mandible subsequent to orthognathic surgery: a case report.

We report the first case of foreign-body granuloma occurring in the mandible of a patient with a history of orthognathic surgery. A 20-year-old male patient had a hard swelling and pain in the left mandibular angle and the parotid area. Plain radiographs showed a radiolucent lesion extending from the buccal area under the left sigmoid notch of the mandible to the mandibular angle. Computed tomographs showed an expanded osteolytic mass in the same area, with destruction of most of the bone on the buccal side. A microscopic examination revealed filamentous foreign material associated with chronic inflammatory cell infiltration and an aggregation of multinucleated giant cells. Foreign-body granuloma in the mandible, although rare, should be included in the differential diagnosis in cases of postoperative masses.

Adult↗

Pamidronate in the treatment of diffuse sclerosing osteomyelitis of the mandible.

Diffuse sclerosing osteomyelitis of the mandible is characterized by bouts of intense pain, sometimes associated with trismus and paresthesia, and leads to progressive deformity. It is of unknown etiopathology, but it is suggested to be one manifestation of the synovitis, acne, pustulosis, hyperostosis, osteomyelitis syndrome, the other features of which may have been overlooked. Treatment results are disappointing, and decortication may be necessary to achieve an acceptable outcome. We report a case restricted to the mandible that responded favorably to treatment with pamidronate. Further trials of pamidronate in patients with diffuse sclerosing osteomyelitis of the mandible, even in those with the aforementioned syndrome, are needed to assess its effectiveness.

Aged↗

Review of segmental and marginal resection of the mandible in patients with oral cancer.

This paper reviews the medical literature of the last decade to ascertain the criteria used to assess mandibular invasion by cancer of the oral cavity and to suggest how best to evaluate the mandible with a view to surgical management. It is generally agreed that patients with mandibular invasion should be treated surgically, but the extent of mandibular resection required remains a controversial matter and the accurate preoperative determination of neoplastic invasion of the mandible remains a challenge for head and neck surgeons. The relative reliability of preoperative orthopantomography, (OPG) bone scanning, computed tomography (CT) and magnetic resonance imaging (MRI), and of peroperative periosteal stripping and direct inspection in clinical assessment for mandibular surgery, is discussed. The histological patterns of tumor invasion and the most common routes of tumor entry in the mandible are described and the influence of variables such as prior radiotherapy and an edentulous vs a dentate state in relation to perineural invasion are also discussed. Finally, a comparison is drawn between the reported outcome of marginal vs segmental resection procedures and a decision-making algorithm is proposed. In selected cases, marginal mandibulectomy can ensure satisfactory tumor control, with a favorable effect on the morbidity associated with mandibular surgery.

Humans↗

Effect of changes in the relationship of the mandible to the maxilla on the dimensions of the external acoustic meatus.

A preliminary study of seven randomly selected subjects was initiated to assay if any changes occur in body posture and in the dimensions of the external acoustic meatus when the relationship of the mandible to the maxilla is changed. The anatomic configurations presented by body posture and the external acoustic meatus, when the mandible was in a position of intercuspation, were used as points of reference. The dimensions of body posture and the external acoustic meatus were recorded for all subjects, when their respective mandibles were in intercuspation, protrusive, retrusive, as well as a position produced by orthopedic splints. Although, the position of intercuspation was used as a point of reference, comparisons of results obtained by all positions used, were made. Changes in the dimensions of body posture and the dimensions of the external auditory meatus were noted with every one of the prescribed alterations of mandibular posture.

Dental Occlusion↗

Rigid internal fixation with miniplates and screws: a cost-effective technique for treating mandible fractures?

Traditional methods of fixation for stabilization of mandible fractures primarily center around intermaxillary fixation with or without open reduction. During the past decade, rigid internal fixation with miniplates and screws has attained widespread acceptance in the management of acute traumatic injuries to the mandible. With continuing emphasis on cost containment in health care delivery, plastic surgeons will be expected to justify their therapeutic methods as beneficial as well as cost-effective. This is particularly important when a number of acceptable procedures are readily available. The purpose of our investigation was retrospectively to compare treatment with intermaxillary fixation alone, interosseous wire osteosynthesis, and rigid internal fixation with miniplates and screws. We analyzed the hospital records of three such treatment groups, each consisting of 25 patients. Despite initial purchase costs, increased operating time, and the need to develop the skills required to apply the hardware, our study clearly demonstrated that miniplates and screws remain a cost-effective approach to caring for fractures of the mandible. Associated advantages include a quicker return to a preinjury life-style, decreased weight loss, improved oral hygiene and wound care, and protection of the airway, thereby eliminating monitored intensive care unit admissions.

Adolescent↗

Computed tomography versus standard radiography in the assessment of fractures of the mandible.

Twenty-nine fractures of the mandible were studied by standard radiographs and axial computed tomographic scans (hard copy). Independent reviewers analyzed each study in a blinded, non-paired fashion. When radiographic diagnostic sensitivities were compared on the basis of known surgical findings, the plain films were found to have a higher diagnostic sensitivity (89%) than the hard copy computed tomograms (64%). This difference occurred primarily with images of nondisplaced fractures in posterior portions of the mandible, and is likely the result of tomographic orientation and volume averaging. Though computed tomography has emerged as the standard diagnostic test in evaluating intracranial and maxillofacial trauma, this study demonstrates that computed tomographic scanning alone is inadequate in excluding nondisplaced fractures of the posterior mandible.

Fracture Fixation, Internal↗

Mandible fragment fixation during reconstruction: the splint-and-plate technique.

One of the most popular methods of mandible fragment fixation is the precontoured reconstruction plate technique. Unfortunately, this method is not a reliable option when tumor distorts the mandibular contour or extends through the buccal cortex of the mandible. An alternative to the precontoured reconstruction plate is the splint-and-plate technique of mandible fragment fixation. An application of this appliance and method in 10 patients revealed the technique's advantages. The splint can be applied quickly and does not obstruct the ablative or reconstructive procedure. Further, the splint accurately keys the dentition and reliably maintains temporomandibular joint relationships. Finally, this technique provides a reference point to the exact position of the symphysis and angle when these landmarks have been resected.

Adult↗

Intraosseous hemangioma of the mandible: a case report and review of the literature.

Intraosseous hemangiomas are benign lesions, occurring often in vertebra and skull. These lesions can present in the head and neck region being the next most common site with a predominance of mandible. There are approximately seventy intraosseous hemangiomas of mandible in literature reported to date. We present an intraosseous hemangioma of the symphysis mandible. We performed a block resection of the mass preserving the mandibular integrity with no complications. There were no recurrences in the follow-up period of 24 months.

Child↗

Diagnosis of aneurysmal bone cyst of the mandible. A report of two cases with emphasis on scintigraphic approaches.

Aneurysmal bone cyst is rarely found in the mandible, and roentgenographic diagnosis of this condition is not easily made. In this report, the diagnostic value of bone scintigraphy and radionuclide angiography and CT imaging in two cases of aneurysmal bone cyst of the mandible are discussed. Bone scintigraphy with Tc-99m MDP demonstrated ring-like or doughnut-pattern accumulation of radioactivity, which corresponded to the expansile character of the bony lesion. The accumulation of radioactivity was intensive in the peripheral region despite the fact that the lesion was benign. Furthermore, the central rarefaction showed that the lesion was cystic. Radionuclide angiography with Tc-99m HSA, including blood pool scan, did not detect radioactive concentration. Thus bone scintigraphy and radionuclide angiography were found to be essential in the differential diagnosis of aneurysmal bone cyst from other forms of tumor, especially hypervascularized tumor and central hemangioma of the mandible.

Angiography↗

Osteogenic sarcoma of the mandible: a plea for radical initial surgery.

A total of 24 cases of osteogenic sarcoma of the mandible have been reported to the SEER Program of the National Cancer Institute from 1973 to 1983. Out of 14 patients whose disease was staged as regional, only 9 were eligible for 5-year survival figures and only 2 are alive, for a 23 percent 5-year cure. For those patients staged as localized, only four of six eligible for 5-year cure survived, for a 66 percent 5-year survival. Considering all patients reported to SEER who were eligible for 5-year cure, the rate is 40 percent. We believe this reflects the practice of localized resection of these tumors. At Charity Hospital of Louisiana at New Orleans there have been 10 cases of osteogenic sarcoma of the mandible since 1948. There have been no 5-year survivors for those operated on by other services, usually by local resection. On the Tulane Plastic Surgery Service, a total of six cases of osteogenic sarcoma of the mandible were treated by radical surgery with 100 percent survival from 11 to 22 years.

Adolescent↗

Modified towel-clamp technique to effect reduction of displaced mandible fractures.

We report a technique that uses a modified standard towel clamp, allowing a single surgeon to perform and maintain an anatomic reduction of displaced mandible fractures simultaneous with the application of internal fixation. The reduced convergent angle of the modified towel clamp allows bicortical engagement of the clamp, which prevents comminution of the fracture or the outer cortex of the mandible. Additionally, the modification allows the clamp to engage the bone with less exposure than conventional towel clamps. In our clinical experience of treating more than 100 mandible fractures a year, this technique proves superior to others described in the literature.

Humans↗

Osseous changes following placement of the transmandibular implant system in edentulous mandibles.

The transmandibular implant system is designed for the reconstruction and rehabilitation of the endentulous mandible utilizing an extraoral approach. Transmandibular implants were placed in 19 patients and mandibular bony changes were followed using standardized panoramic radiography. Eleven sites were identified on each postoperative radiograph and the percentage of radiographic enlargement was calculated for each site. The true bony changes were then computed for both short-term (9.4 months) and long-term (53.4 months) follow-up. Patients with an average mandibular height in the saddle areas of 3.5 to 8.9 mm showed bilateral bony regeneration in the saddle areas and over the most distal cortical screws of the implants. Most of these bony changes were seen in the first year, but continued beyond that time. Patients with residual bone height of 9.0 to 12.9 mm had little bone change, while patients with bone height of 13.0 to 20.5 mm demonstrated slight resorption. Theories for the observed changes are presented. The transmandibular implant is especially indicated for the severely atrophic mandible because its position within the mandible and the rigid box frame design of the implant promote bilateral bone regeneration distal to the framework of the implant.

Aged↗