Susumu Omura

A carrier for clinical use of recombinant human BMP-2: dehydrothermally cross-linked composite of fibrillar and denatured atelocollagen sponge

The clinical applicability of a dehydrothermally cross-linked composite of fibrillar and denatured atelocollagen sponge (DCFD-AS), as a carrier of recombinant human bone morphogenetic protein-2 (rhBMP-2) was evaluated in the rat subcutaneous pouch. After four weeks, DCFD-AS with rhBMP-2 formed compact bone, without undergoing significant changes in shape and size, by means of intramembranous ossification. The ultimate size, shape and location of induced new bone was accurately controlled by the carrier. Low antigenicity of soluble atelocollagen, cross-linking without chemicals, the combination of gelatin with fibrillar collagen, and the spongy structure probably all contributed to new bone formation through intramembranous ossification without inducing an inflammatory response. Atelocollagen sponge is easily sterilized, can be stored at room temperature, and can act as a rhBMP-2 carrier without the need for complex procedures.

A newly developed collagen/silicone bilayer membrane as a mucosal substitute: a preliminary report

A new bilayer membrane proved effective as a mucosal substitute. The membrane is composed of an outer layer of silicone and an inner layer of dehydrothermally cross linked composites of fibrillar and denatured collagen sponge. The membrane was placed on oral mucosal defects of five patients after operations for cancer. Ten to 14 days after application the outer silicone sheet was removed, leaving only the inner collagen sponge layer into which cellular tufts of fibroblasts and capillaries had infiltrated. The infiltrated collagen matrix became a new connective tissue that epithelialised rapidly by migration of peripheral epithelium 4-5 weeks after application. In all cases the postoperative course was unremarkable and the repair was effective.

Oral manifestations and differential diagnosis of isolated hypoglossal nerve palsy: report of two cases

Isolated hypoglossal nerve palsy is rare, but occasionally it appears as the initial or solitary sign of an intracranial or extracranial space-occupying lesion, a head and neck injury, or a vascular abnormality of the internal carotid artery. Therefore it should be considered in differential diagnosis. We report two cases of isolated unilateral hypoglossal nerve palsy. In Case 1 the cause of the palsy appeared to be hypoglossal nerve neurilemmoma within the hypoglossal canal, whereas in Case 2 the cause could not be identified. Neither patient complained of any disability other than slight dysarthria. The tongue deviated toward the healthy side at rest and toward the affected side on protrusion. Hemiatrophy of the tongue with fatty displacement was demonstrated by means of T1-weighted magnetic resonance imaging. Dentists who might at times see patients with isolated hypoglossal nerve palsy should be aware of the significance of its oral manifestation, and they should be able to perform differential diagnosis of patients with the condition who appear for treatment.

Differential diagnosis of cervical lymphadenopathy with intranodal color Doppler flow signals in patients with oral squamous cell carcinoma.

OBJECTIVEnThe purpose of this study was to differentiate reactively enlarged cervical nodes from metastatic nodes by means of color Doppler flow imaging in patients with oral squamous cell carcinoma.nnnSTUDY DESIGNnEnlarged lymph nodes with long-axis diameters greater than 10 mm in 30 patients were classified into 4 groups according to color Doppler flow imaging findings. After the patients underwent neck dissection, the findings were correlated with the pathologic features.nnnRESULTSnColor Doppler flow imaging detected 58 enlarged nodes with long-axis diameters greater than 10 mm. Thirty-five lymph nodes showed no color flow signals; of these, 32 (91%) were metastatic and 3 were reactive. Of the 12 lymph nodes with central color flow signals, 11 (92%) were reactively enlarged and 1 was metastatic.nnnCONCLUSIONSnThe presence of central signals on color Doppler flow imaging appeared to be a significant parameter associated with reactively enlarged benign nodes in patients with oral squamous cell carcinoma.

Comparison between hockey stick and reversed hockey stick incision: gently curved single linear neck incisions for oral cancer

Hockey stick incision (HSI) and reversed-HSI are known to be useful incisions for lymph node dissections of the neck. Both are gently curved single linear incisions without three-point suture line junctions, but are different at the base of the skin flap. The HSI allows the elevation of a superiorly-based single cervical skin flap and the reversed-HSI allows for an inferiorly-based flap. We compared the viability of the skin flaps, exposure of the operation field and cosmetic results to evaluate the characteristics of each incision. HSI appeared to be the suitable incision for radical neck dissection due to adequate exposure of the operation field while rendering excellent cosmetic results. Reversed-HSI was applied in combination with block resection of parts of the oral cavity because it provided much better exposure of the operation field than HSI, while still achieving acceptable cosmetic results. Using this technique, a small area of marginal necrosis was occasionally seen at the apex of the skin flap due to poor blood supply.

Excessive rapid palatal expansion with latham appliance for distal repositioning of protruded premaxilla in bilateral cleft lip and alveolus

Objective: This article reports a case of bilateral cleft lip and alveolus (BCLA) for which excessive rapid palatal expansion with a Latham appliance was performed for preoperative alignment of the protruded premaxilla. Postoperative changes of maxillary width were investigated with serial plaster casts. Patient and Results: A 3-month-old girl presented with complete BCLA in which the premaxilla was markedly protruded. Preoperative alignment of the protruded premaxilla with a Latham appliance was planned to facilitate primary lip repair. The appliance was placed when the patient was 4.5 months old. The necessary palatal expansion was estimated to be 7.0 mm in order to move the premaxilla backward into the ideal position. After palatal expansion and posterior repositioning of the protruded premaxilla, the primary operation, including cheiloplasty and gingivoperiosteoplasty, was performed when the patient was 7 months old. Excessive maxillary expansion might be a cause of transverse maxillomandibular discrepancy. Measurement with serial plaster casts demonstrated that maxillary widths increased from 42.3 mm pretreatment to 49.0 mm after orthopedic treatment but relapsed markedly to 43.5 mm at 3 months after the primary operation. Therefore, the net change of maxillary widths was only 1.2 mm. After alignment of the protruded premaxilla, tension-free soft tissue repairs were performed, and a harmonious alveolar arch was obtained without change in maxillary width. Conclusion: These results indicate that this method is useful for preoperative management of BCLA with protruded premaxilla.

Intraoperative lacrimal intubation to prevent epiphora as a result of injury to the nasolacrimal system after fracture of the naso-orbitoethmoid complex.

Treatment of fracture of the naso-orbitoethmoid (NOE) complex is difficult. There are not only aesthetic issues but also functional consequences related to the lacrimal system. Because prophylactic lacrimal intubation for such fractures remains controversial, we have assessed the effectiveness of intraoperative lacrimal intubation to prevent epiphora as a result of such injuries. Thirteen patients diagnosed with craniomaxillofacial fractures including fractures of the NOE complex were included in the study; 10 had unilateral fractures and 3 bilateral. Computed tomography (CT) showed all patients had displaced fragments that had the potential to damage the lacrimal duct. In 7 patients the fractures included the canthal region and in 6 they did not. All patients were treated by open reduction and internal fixation under general anaesthesia, followed by intraoperative lacrimal intubation unilaterally or bilaterally as required. Lacrimal intubation with a silicone tube was successful in all 13 patients (16 sides). The tube was removed 2-9 months (mean 3.8) postoperatively and no subsequent epiphora were seen during follow-up (mean (3-29 months) 11.3 months). Lacrimal intubation for at least 2 months may prevent epiphora caused by injury to the nasolacrimal system after fractures of the NOE complex.

Rapid tumor necrosis induced by electrochemotherapy with intratumoral injection of bleomycin in a hamster tongue cancer model

This study evaluated the effects of electrochemotherapy (ECT) with intratumoral injection of bleomycin (BLM) on the chemically induced tongue cancer model in the hamster. Intratumoral injection of BLM followed by high-voltage electrical treatment induced rapid necrosis of the tumor within 48 hours and subsequent rapid tumor volume reduction. Three weeks after the ECT with BLM, 3 of the 6 animals showed no palpable tumor, while no antitumor effects were observed in the control groups. Because of the remarkable antitumor effect with no major observed side effects, we concluded that ECT combined with intratumoral injection of BLM has the potential to enhance treatment results for tongue cancer.

Maxillary movement in distraction osteogenesis using internal devices in cleft palate patients.

Objective The purpose of this cephalometric study was to compare the actual movement with the planned movement of the maxilla by using internal maxillary distraction in cleft lip and palate patients. Patients Twelve patients, including eight with unilateral and four with bilateral cleft lip and palate, underwent maxillary advancement with internal maxillary distractors. Main Outcome Measures Lateral cephalometric radiographs obtained preoperatively, predistraction, and postdistraction were used for analysis. The movement of the maxilla, angular change of the internal devices and rotation of the mandible were measured at each stage, and the planned vector of advancement predicted from the placement vector of the distractors was compared with the actual vector. Results Internal maxillary distractors were rotated in a clockwise direction during the distraction period. The angular change of the distractors was 7.7°. The amount of actual advancement at anterior nasal spine with distraction was 6.3 mm, which represented about 70% of the distance of activation of distraction. The actual advanced vector at anterior nasal spine was 9.7 smaller than the planned vector. The mandible underwent a clockwise rotation of 3.5°. Conclusion In the internal distraction technique, the maxilla was advanced inferiorly to the planned vector and with a slight clockwise rotation. These results are useful for surgical planning when using internal distractors.

Novel OK-432-conjugated Tumor Vaccines Induce Tumor-specific Immunity against Murine Tongue Cancer

Priming with tumor antigens is one of the most important strategies in cancer immunotherapy. To enhance tumor antigenicity, OK-432, a streptococcal preparation, was coupled to squamous cell carcinoma (KLN-205) by means of a 0.2% glutaraldehyde method. The purpose of this study was to investigate whether OK-432-conjugated tumor vaccines could induce tumor-specific immunity. Our originally developed mouse tongue cancer model was used throughout this work for the analysis of antitumor effects. Prepared OK-432-conjugated KLN-205 vaccines were immunized 3 times to DBA/2 mice. The results showed that the KLN-205 vaccines induced cytolytic activity and strongly suppressed both KLN-205 tumor incidence and growth, and survival of the mice was improved. Moreover, the histological results showed that a greater number of lymphocytes had infiltrated around tumor cells by 24 hours after tumor inoculation in the vaccine group. These results suggest that immunizations with KLN-205 vaccines increase the antitumor effects against tongue cancer.