Yasuharu Takenoshita

Comparison of Functional Recovery After Nonsurgical and Surgical Treatment of Condylar Fractures

This article evaluates 16 cases of condylar fracture treated surgically, comparing them with the 20 cases treated nonsurgically, with a 2-year follow-up. Although severely displaced and luxated fractures were involved in the surgical group with rigid internal fixation, satisfactory postoperative function and occlusion were achieved at the same level as in the nonsurgical group, without severe complications.

Complications of miniplate osteosynthesis for mandibular fractures

Postoperative complications of delayed osteosynthesis with stainless steel miniplates were examined in 110 patients with mandibular fractures. The miniplates were removed in 91 of the patients, even if symptom-free, once sufficient bony union was obtained, and the healing conditions and the surrounding tissues were examined. Malocclusion, exposure of miniplates, delayed union, and infection were observed in 3.6%, 3.6%, 1.8%, and 1.0% of the patients, respectively. The complication rates were within acceptable limits even when treatment was performed later than 24 hours after injury. The healing conditions and the surrounding tissues did not show any serious problems. Thus, at least in short-term retention, stainless steel miniplates seem to be effective and suitable for osteosynthesis of mandibular fractures.

Surgical treatment of fractures of the mandibular condylar neck

In this paper, the authors describe their surgical procedures, the clinical management, and radiological evaluation of condylar neck fractures. The condylar neck is the site of approximately two-thirds of all mandibular fractures. These are treated either conservatively or by open reduction. Indications for open reduction are discussed. Approximately 5-30% of all condylar neck fractures are treated surgically, depending on the circumstances of each case. The role of open reduction is realignment of segments, early function and decreased post-operative complaints. It has been our experience that surgical treatment of selected condylar neck fractures is successful.

Age-related changes in the human mandibular condyle: A morphologic, radiologic, and histologic study☆

PURPOSE This study determined the osteoarthrotic changes in the human mandibular condyle in relation to aging and the loss of dental occlusal contacts. MATERIALS AND METHODS Thirty-four condyles obtained at autopsy were studied morphologically, radiologically, and histologically. RESULTS With advancing age, the articular surface of the mandibular condyle morphologically showed severe degenerative changes. The condyles with these changes tended to be from the side of the mandible with minimal areas of occlusal contact. Radiographically, an irregularity of the cortical bone plate was most commonly seen in the fifth and sixth decades, whereas a polygonal or flattened structure was mainly observed after the seventh decade. CONCLUSION The histologic findings suggest that a decrease in the cellular components with advancing age may play a critical role in the development of degenerative changes.

Interleukin-1α-dependent Regulation of Matrix Metalloproteinase-9 (MMP-9) Secretion and Activation in the Epithelial Cells of Odontogenic Jaw Cysts:

Interleukin-la (IL-1α) and matrix metalloproteinase-9 (MMP-9) are thought to be involved in odontogenic cyst expansion. In this study, we investigated the effects of IL-1α on the secretion and activation of MMP-9 in odontogenic jaw cysts. An active form of MMP-9 was present in odontogenic keratocyst (6 of 8 cases) fluids more frequently than dentigerous cyst (3 of 10 cases) and radicular cyst (3 of 10 cases) fluids, although proMMP-9 was present in all cyst fluids. Odontogenic keratocyst fragments in explant culture secreted a larger amount of IL-1α than dentigerous cyst and radicular cyst fragments in explant culture, and spontaneously secreted both proMMP-9 and an active form of MMP-9. The fragments of dentigerous cysts and radicular cysts secreted a small amount of proMMP-9, but no active form of MMP-9. Exogenously added recombinant human IL-1α (rhIL-la) increased the secretion and activation of proMMP-9 in the fragments of dentigerous cysts and radicular cysts. The epithelial cells isolated from odontogenic keratocysts secreted IL-la and proMMP-9 without stimulation. Under the cultivation on a fibronectin-coated dish, rhIL-la increased the secretion of proMMP-9 from the epithelial cells in a dose-dependent manner. Moreover, rhIL-la induced the secretion of proMMP-3 and plasminogen activator urokinase (u-PA) from the epithelial cells, and converted the secreted proMMP-3 to the active form in the presence of plasminogen. The secreted proMMP-9 was also activated in the presence of rhIL-la and plasminogen. Hence, our results suggest that IL-1α may up-regulate not only proMMP-9 secretion but also proMMP-9 activation by inducing proMMP-3 and u-PA production in the cyst epithelial cells by autocrine/paracrine regulatory mechanisms.

Natural course of jaw lesions in patients with familial adenomatosis coli (Gardner's syndrome)

Twenty-three patients suffering from familial adenomatosis coli (FAC) were followed for an average of 7 years (0.11-16.11 years). In 22 patients, jaw lesions including osteomas and/or odontomas were present at the first examination. In 12 patients, some changes occurred; that is, the number and size of the lesions increased. These findings indicate that changes of jaw lesions in FAC patients occur gradually even in adulthood.

Magnetic resonance imaging of oral and maxillofacial angiomas

Eleven patients with oral and maxillofacial angiomas (seven hemangiomas and four lymphangiomas) were evaluated with magnetic resonance imaging using a 0.2-T permanent system and spin-echo pulse sequences. These lesions typically had signal intensities that were iso T1-weighted, similar to muscle, and high T2-weighted, greater than subcutaneous fat. Nine tumors had well- or relatively well-defined margins, and seven cases had curvilinear structures of low signal intensities in the masses on T2-weighted images. It was impossible to distinguish hemangiomas from lymphangiomas on MR images. Our experience suggested that most angiomas of oral and maxillofacial regions present special characteristics on magnetic resonance images. It is thought that information obtained with magnetic resonance images can contribute significantly to the evaluation of the extent of these lesions.

Marsupialisation for keratocystic odontogenic tumours in the mandible: longitudinal image analysis of tumour size using 3D visualised CT scans

The purpose of this study was to determine how keratocystic odontogenic tumours (KCOTs) in the mandible are reduced during marsupialisation, and to predict the best time for secondary enucleation by analysing computed tomography (CT) images. 15 patients with KCOTs were treated with marsupialisation surgery, and 42 series of CT data taken during the marsupialisation process were analysed. CT data were reconstructed in three-dimensional (3D) images. The 3D images were used to measure the diameter and volume, and to analyse the changes that occurred after marsupialisation. Marsupialised KCOTs tended to be reduced equally towards the window in the tumour. The amount of volume reduction per day (V(r)) was reduced in proportion to the volume (V) with the formula V(r)=-0.0029×V. The formula manipulation for V was V=V(0)×e(-0.0029t) (t=duration after marsupialisaton (day)). The volume of marsupialised KCOTs was reduced by half over a 239 day cycle. These results demonstrate that the future shape of marsupialised mandibular KCOTs, under good control, could be predicted with significant accuracy using CT data. This prediction could decrease the prolonged marsupialisation state in patients with KCOTs.

Widespread radiopacity of jaw bones in familial adenomatosis coli

Abnormalities of jaw bones and teeth were evaluated in 37 patients with familial adenomatosis coli (FAC) by means of orthopantomography. Osteomatous radiopaque lesions were evident in 75.7 percent of FAC patients (focal type: 62.2% and wide spread type: 13.5%), odontomes in 29.7% peripheral osteomas in 13.5%, unerupted teeth in 16.2% and supernumerary unerupted teeth in 16.2%. Five of the 37 FAC patients had an unusual widespread type of radiopacity with other abnormalities. Combined abnormalities were most frequent in patients with this type in comparison with patients with the focal type. Osteomas and peripheral osteomas were revealed in this type with statistical significance. Biopsy performed in one patient revealed an osteoma. These results suggest that the multiple abnormalities seen in oral X-ray examination may predict the occult existence of familial adenomatosis coli and these widespread radiopaque lesions probably represent the most extensive manifestation of FAC.

Carotid-cavernous sinus fistula accompanying facial trauma: report of a case, with a review of the literature

A case of traumatic carotid-cavernous sinus fistula, an abnormal communication at the base of the skull between the internal carotid artery and the cavernous sinus, complicating fractures of the zygoma and mandible is described. Typical signs and symptoms appeared immediately after the injury resulting from a traffic accident. Angiography revealed a definite CCSF and a balloon embolization was performed with a good result. The importance of a multidisciplinary examination of the ophthalmic function and periorbital condition following trauma is emphasized, and interdepartmental cooperation helped to establish a rational diagnosis and obtain a good result.