Comparative Efficacy of Granisetron and Droperidol After Orthognathic Surgery for Prophylaxis of Postoperative Nausea and Vomiting: A Retrospective Study

BACKGROUND

In the fall of 2021, granisetron was approved for postoperative nausea and vomiting (PONV) management in Japan. However, the comparative efficacy of droperidol and granisetron in the field of orthognathic surgery has not been determined.

PURPOSE

We compare the efficacy of droperidol and granisetron for PONV prophylaxis following orthognathic surgery.

STUDY DESIGN, SETTING, SAMPLE

We performed a retrospective cohort study of patients who underwent orthognathic surgery at a single institution from September 2020 to December 2022. Patients who had undergone Le Fort I osteotomy with sagittal split ramus osteotomy or isolated sagittal split ramus osteotomy were included. Patients were divided into three groups; the isolated droperidol (D), isolated granisetron (G), and droperidol with granisetron (DG) groups. General anesthesia was performed using total intravenous anesthesia for all patients; however, droperidol and granisetron were administered at the anesthesiologist's discretion.

PREDICTOR VARIABLE

PONV prophylactic therapy included isolated droperidol, isolated granisetron, and droperidol with granisetron administration.

OUTCOME VARIABLES

Postoperative nausea (PON) and postoperative vomiting (POV) were determined through medical examination within 48 hours following surgery. Secondary outcomes included complications due to droperidol and/or granisetron administration.

COVARIATES

Age, sex, body mass index, Apfel's score, duration of surgery, duration of anesthesia, intraoperative blood loss, and type of surgery.

ANALYSES

Statistical analysis was conducted using Fisher exact test, Mann-Whitney U test with Bonferroni correction for univariate comparison, and modified Poisson regression for comparison of PON and POV prophylactic efficacy for multivariate analyses. P values <.05 were considered statistically significant.

RESULTS

Our study included 218 participants. There were no significant differences in covariates between groups D (n = 111), G (n = 52), and DG (n = 55). No significant difference in PON incidence was observed between groups. However, POV incidence was significantly lower in group DG than group D (relative risk, 0.21; 95% confidence interval, 0.05 to 0.86; P = .03). No significant difference in complication incidence was observed between groups.

CONCLUSIONS AND RELEVANCE

Granisetron was as effective as droperidol for PONV management, while droperidol combined with granisetron was more effective than isolated droperidol for POV management. As compared to the use of each drug separately, their combination was considered safe, with no increase in complication rates.

Clinical risk factors for severity and prognosis of antiresorptive agent-related osteonecrosis of the jaw: a retrospective observational study

INTRODUCTION

The incidence of antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is rare, and its management has not yet been established. This study aimed to investigate the predictors for advanced stage and healing of ARONJ to establish an appropriate treatment strategy.

MATERIALS AND METHODS

We retrospectively analyzed patients diagnosed with ARONJ at Kobe City Medical Center General Hospital between April 2014 and March 2020. Outcomes were defined as stage ≥ 2 ARONJ (primary) and healing of ARONJ (secondary). Multivariate logistic regression analysis was used to detect factors associated with the outcomes, and odds ratios (OR) and 95% confidence intervals (CI) were calculated.

RESULTS

This study included 143 patients (stage ≥ 2 ARONJ, 51%; healing of ARONJ, 60%). Multivariate logistic regression analysis revealed that advanced age (per year) (OR 1.037; 95% CI 1.003-1.072; p = 0.028) and serum albumin (per g/dL) (OR 0.430; 95% CI 0.213-0.869; p = 0.018) were significantly associated with stage ≥ 2 ARONJ. Furthermore, multivariate logistic regression analysis revealed that cancer (yes) (OR 0.099; 95% CI 0.029-0.339; p < 0.001), conservative surgical treatment (yes) (OR 15.42; 95% CI 5.657-42.0; p < 0.001), C-reactive protein (per mg/dL) (OR 0.599; 95% CI 0.415-0.864; p < 0.001), and vitamin D analog (yes) (OR 0.167; 95% CI 0.034-0.827; p = 0.028) were factors associated with healing.

CONCLUSION

Our findings suggest that age and hypoalbuminemia are associated with the severity of ARONJ, and cancer, high inflammation, and vitamin D analog may impair healing. In contrast, conservative surgical treatment can overcome the poor treatment outcomes associated with ARONJ.

Clinical features and antimicrobial susceptibility of oral bacteria isolated from the blood cultures of patients with infective endocarditis

Background/purpose

The epidemiology of infective endocarditis (IE) is under constant change due to the aging society and increases in antimicrobial-resistant pathogens. However, IE remains severe. This study aimed to review the current clinical characteristics of IE and the antimicrobial susceptibility of oral bacteria (OB) isolated from blood cultures to implement appropriate antimicrobial prophylaxis.

Materials and methods

We retrospectively investigated the clinical features of 180 patients with IE in whom OB and pathogens except OB (eOB) were identified as causative microorganisms via blood cultures. The susceptibility of the OB group to eight antibiotics was examined by broth microdilution.

Results

Among causative microorganisms, the isolation rate of staphylococci was slightly higher than that of OB; however, the difference was not significant (36.7% vs. 33.8%, p = 0.3203). The number of patients with underlying cardiac disease was significantly higher in the OB group than in the eOB group (53.7% vs. 34.1%, p = 0.0113). Only one ampicillin-resistant OB was detected (2.0%). OBs were significantly less susceptible to clarithromycin and azithromycin than to ampicillin (98.0% vs. 66.7% and 98.0% vs. 60.0%, p = 0.0003 and p = 0.0003, respectively). Moreover, OBs were significantly less susceptible to clarithromycin and azithromycin than to clindamycin (66.7% vs. 88.2% and 60.0% vs. 88.2%, p = 0.0301 and p = 0.0217, respectively).

Conclusion

OBs were susceptible to ampicillin. However, the susceptibility of OBs to clarithromycin and azithromycin was significantly lower than that to ampicillin and clindamycin. These results are important and should help decisions regarding guide antimicrobial prophylaxis.

Postoperative dysphagia caused by a delay in mandibular fracture treatment in a patient with severe intellectual disability: a case report

Background

The postoperative complications of mandibular fracture include malocclusion, infection, nonunion, osteomyelitis, and sensorial mental nerve dysfunction. However, there are no reports regarding postoperative dysphagia as a complication of mandibular fracture. Herein, we report a rare case of postoperative dysphagia caused by delayed mandibular fracture treatment in a patient with severe intellectual disability.

Case presentation

A 46-year-old Japanese male patient with severe intellectual disability fell down and struck his chin. The patient was referred to our department 10 days after the accident. Upon examination, he could not close his mouth because of severe left mandibular body fracture. Open reduction and internal fixation was performed under general anesthesia 16 days after sustaining the injury, and normal occlusion was eventually achieved. However, the patient could not swallow well a day after surgery. He was then diagnosed with postoperative dysphagia caused by disuse atrophy of muscles for swallowing based on videoendoscopic examination findings. Adequate dysphagia rehabilitation could not be facilitated because of the patient’s mental status. Postoperative dysphagia did not improve 21 days after surgery. Therefore, percutaneous endoscopic gastrostomy was required.

Conclusions

The treatment course of the patient had two important implications. First, postoperative dysphagia caused by disuse atrophy may occur if treatment is delayed in severe mandibular body fracture. Second, in particular, if a patient with severe intellectual disability develops postoperative dysphagia caused by disuse atrophy, adequate dysphagia rehabilitation cannot be facilitated, and percutaneous endoscopic gastrostomy may be required. Therefore, early open reduction and internal fixation is required for mandibular fracture in a patient with severe intellectual disability.

A Case of Infective Endocarditis Due to Oral Streptococci After Perioperative Oral Function Management

Infective endocarditis is an extremely serious disease that can present with a variety of clinical manifestations, including infection of valves and endocardium, in patients with cardiac disease, and is associated with risk factors such as invasive dental procedures, caries, and periodontal disease. On the other hand, it has been shown that perioperative oral function management before various surgeries, such as those for malignant tumors, cardiovascular disease, and transplantation, may prevent or reduce postoperative complications. Close coordination between the dentist and cardiac surgeon is especially necessary before heart valve surgery because of the risk of severe complications. The number of perioperative oral management procedures being performed in community dental clinics is increasing. In the absence of clear guidelines, the physician-in-charge usually determines how to best perform oral management while considering the patient’s needs. We report a case of infective endocarditis occurring after perioperative oral management in a young patient with good oral hygiene. This case shows that standardization of the techniques and widespread dissemination of the guidelines are required. Patients should be counseled regarding the importance of maintaining oral hygiene from a young age.

This case report should act as a cautionary tale not only for hospital clinicians but also for community medical and dental practitioners, as the number of such patients is expected to increase in the future.

Risk evaluation of denosumab and zoledronic acid for medication-related osteonecrosis of the jaw in patients with bone metastases: a propensity score-matched analysis

PURPOSE

This study evaluated the risk of medication-related osteonecrosis of the jaw (MRONJ) in patients with cancer who received denosumab or zoledronic acid (ZA) for treating bone metastasis.

METHODS

The medical records of patients were retrospectively reviewed. Patients who did not undergo a dental examination at baseline were excluded. The primary endpoint was a comparison of the risk of developing MRONJ between the denosumab and ZA groups. Propensity score matching was used to control for baseline differences between patient characteristics and compare outcomes for both groups.

RESULTS

Among the 799 patients enrolled, 58 (7.3%) developed MRONJ. The incidence of MRONJ was significantly higher in the denosumab group than in the ZA group (9.6% [39/406] vs. 4.8% [19/393], p = 0.009). Multivariate Cox proportional hazards regression analysis revealed that denosumab treatment (hazard ratio [HR], 2.89; 95% confidence interval [CI], 1.65-5.25; p < 0.001) and tooth extraction after starting ZA or denosumab (HR, 4.26; 95% CI, 2.38-7.44; p < 0.001) were significant risk factors for MRONJ. Propensity score-matched analysis confirmed that the risk of developing MRONJ was significantly higher in the denosumab group than in the ZA group (HR, 2.34; 95% CI, 1.17-5.01; p = 0.016).

CONCLUSION

The results of this study suggest that denosumab poses a significant risk for developing MRONJ in patients treated for bone metastasis, and thus these patients require close monitoring.

Switching from zoledronic acid to denosumab increases the risk for developing medication-related osteonecrosis of the jaw in patients with bone metastases

Purpose

Switch from zoledronic acid (ZA) to denosumab may increase the risk of medication-related osteonecrosis of the jaw (MRONJ) owing to the additive effect of denosumab on the jawbone and residual ZA activities. We evaluated the risk of developing MRONJ in patients who received ZA, denosumab, or ZA-to-denosumab for the treatment of bone metastases.

Methods

The medical charts of patients with cancer who received denosumab or ZA for bone metastases were retrospectively reviewed. Patients who did not undergo a dental examination at baseline were excluded. Primary endpoint was the evaluation of the risk of developing MRONJ in the ZA-to-denosumab group. Secondary endpoints were probability of MRONJ and the relationship between risk factors and the time to the development of MRONJ.

Results

Among the 795 patients included in this study, 65 (8.2%) developed MRONJ. The incidence of MRONJ was significantly higher in the ZA-to-denosumab group than in the ZA group [7/43 (16.3%) vs. 19/350 (5.4%), p = 0.007]. Multivariate Cox proportional hazards regression analysis revealed that denosumab treatment [hazard ratio (HR), 2.41; 95% confidence interval (CI), 1.37–4.39; p = 0.002], ZA-to-denosumab treatment (HR, 4.36; 95% CI, 1.63–10.54, p = 0.005), tooth extraction after starting ZA or denosumab (HR, 4.86; 95% CI, 2.75–8.36; p < 0.001), and concomitant use of antiangiogenic agents (HR, 1.78; 95% CI, 1.06–2.96; p = 0.030) were significant risk factors for MRONJ.

Conclusion

Our results suggest that switching from ZA to denosumab significantly increases the risk for developing MRONJ in patients with bone metastases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04262-w.

Associated characteristics and treatment outcomes of medication-related osteonecrosis of the jaw in patients receiving denosumab or zoledronic acid for bone metastases

Purpose

This study aimed to evaluate the association between clinical characteristics and development of medication-related osteonecrosis of the jaw (MRONJ) in patients who underwent dental examinations before the initiation of treatment with denosumab or zoledronic acid, which are bone-modifying agents (BMAs), for bone metastases. Additionally, the clinical outcomes of patients who developed MRONJ were evaluated along with the time to resolution of MRONJ.

Methods

The medical charts of patients with cancer who received denosumab or zoledronic acid for bone metastases between January 2012 and September 2016 were retrospectively reviewed. Patients were excluded if they did not undergo a dental examination at baseline.

Results

Among the 374 included patients, 34 (9.1%) developed MRONJ. The incidence of MRONJ was significantly higher in the denosumab group than in the zoledronic acid (27/215 [12.6%] vs 7/159 [4.4%], P = 0.006) group. Multivariate Cox proportional hazards regression analysis revealed that denosumab treatment, older age, and tooth extraction before and after starting BMA treatments were significantly associated with developing MRONJ. The time to resolution of MRONJ was significantly shorter for patients who received denosumab (median 26.8 months) than for those who received zoledronic acid (median not reached; P = 0.024).

Conclusion

The results of this study suggest that treatment with denosumab, age > 65 years, and tooth extraction before and after starting BMA treatments are significantly associated with developing MRONJ in patients undergoing treatment for bone metastases. However, MRONJ caused by denosumab resolves faster than that caused by zoledronic acid.

Development of Antiresorptive Agent-Related Osteonecrosis of the Jaw After Dental Implant Removal: A Case Report

Dental implant treatment is a highly predictable therapy, but when potentially lethal symptoms or complications occur, dentists must remove the implant fixture. Recently, reports on antiresorptive agent-related osteonecrosis of the jaw have increased in the field of dental implants, although the relationship between dental implant treatment and antiresorptive agents remains unclear. Here, we report a case of antiresorptive agent-related osteonecrosis of the jaw that developed after dental implant removal. A 67-year-old Japanese woman with a medical history of osteoporosis and 7 years of oral bisphosphonate treatment was referred to our hospital with a chief complaint of painful right mandibular bone exposure. A family dentist removed the dental implants from the right mandible using a trephine drill without flap elevation in August 2016. However, the healing was impaired; she was referred to our hospital 3 months after the procedure. We performed a sequestrectomy of the mandible under general anesthesia. In conclusion, this patient's course has two important implications: First, the removal of dental implants from patients who are prescribed oral bisphosphonates for long durations can cause antiresorptive agent-related osteonecrosis of the jaw. Second, meticulous procedures are required to prevent and treat the development of antiresorptive agent-related osteonecrosis of the jaw after dental implant removal.

Actinomycotic Osteomyelitis of the Mandible Diagnosed Using Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry: A Case Report

Actinomycosis is a rare, chronic, slowly progressive granulomatous disease caused by filamentous gram-positive anaerobic bacteria from the Actinomycetaceae family (genus Actinomyces). It has become a rare condition because of the widespread use of antibiotics. When clinical symptoms are not typical, diagnosis of this condition becomes difficult. This report describes a case involving an 82-year-old woman who was diagnosed with actinomycotic osteomyelitis of the mandible using matrix assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). The patient was referred to the authors' department with chief complaints of swelling, multiple fistulae in the left preauricular region, and trismus. The authors performed fine-needle aspiration microbiology (FNAM) and identified Actinomyces oris using MALDI-TOF MS. A diagnosis of actinomycotic osteomyelitis of the mandible was made and the patient was treated with minocycline and extraction of the culprit tooth. The findings from this case have 2 important implications. First, for patients with clinically suspected actinomycosis, bacteriologic examinations should include not only surface swab tests but also FNAM; moreover, communication with the laboratory medical technologist is important to improve detection of the causative organisms. Second, MALDI-TOF MS could be an effective tool for improving the diagnosis and treatment outcomes of actinomycosis.

Surgical Ciliated Cyst Following Maxillary Sinus Floor Augmentation: A Case Report

Maxillary sinus floor augmentation is considered to play a critical role in dental implant treatment. Although many complications, such as maxillary sinusitis and infection, are well known, few reports are available on the risk of surgical ciliated cyst following the procedure. Here, we report a case of surgical ciliated cyst following maxillary sinus floor augmentation. A 55-year-old Japanese woman was referred to our hospital because of alveolar bone atrophy in the bilateral maxilla. We performed bilateral maxillary sinus floor augmentation by the lateral window technique without covering the window. The Schneiderian membrane did not perforate during the operation. She returned to our hospital after 9 years due to swelling of the left buccal region. Computerized tomography revealed a well-defined radiolucent area with radiodense border intraosseously localized in the left maxilla. We performed enucleation of the cyst with the patient under general anesthesia. Histological examination of the specimen showed a surgical ciliated cyst. In conclusion, the course of this patient has 2 important implications. First, the sinus membrane entrapped in the grafted bone without visible perforation and or tearing can develop into a surgical ciliated cyst. Second, there is a possibility that covering the lateral window tightly might prevent the development of a surgical ciliated cyst.

Gate-Tunable Spin-Charge Conversion and the Role of Spin-Orbit Interaction in Graphene

The small spin-orbit interaction of carbon atoms in graphene promises a long spin diffusion length and the potential to create a spin field-effect transistor. However, for this reason, graphene was largely overlooked as a possible spin-charge conversion material. We report electric gate tuning of the spin-charge conversion voltage signal in single-layer graphene. Using spin pumping from an yttrium iron garnet ferrimagnetic insulator and ionic liquid top gate, we determined that the inverse spin Hall effect is the dominant spin-charge conversion mechanism in single-layer graphene. From the gate dependence of the electromotive force we showed the dominance of the intrinsic over Rashba spin-orbit interaction, a long-standing question in graphene research.

Electrically induced ambipolar spin vanishments in carbon nanotubes

Carbon nanotubes (CNTs) exhibit various excellent properties, such as ballistic transport. However, their electrically induced charge carriers and the relation between their spin states and the ballistic transport have not yet been microscopically investigated because of experimental difficulties. Here we show an electron spin resonance (ESR) study of semiconducting single-walled CNT thin films to investigate their spin states and electrically induced charge carriers using transistor structures under device operation. The field-induced ESR technique is suitable for microscopic investigation because it can directly observe spins in the CNTs. We observed a clear correlation between the ESR decrease and the current increase under high charge density conditions, which directly demonstrated electrically induced ambipolar spin vanishments in the CNTs. The result provides a first clear evidence of antimagnetic interactions between spins of electrically induced charge carriers and vacancies in the CNTs. The ambipolar spin vanishments would contribute the improvement of transport properties of CNTs because of greatly reduced carrier scatterings.

Formation of a stable p-n junction in a liquid-gated MoS2 ambipolar transistor

Molybdenum disulfide (MoS2) has gained attention because of its high mobility and circular dichroism. As a crucial step to merge these advantages into a single device, we present a method that electronically controls and locates p-n junctions in liquid-gated ambipolar MoS2 transistors. A bias-independent p-n junction was formed, and it displayed rectifying I-V characteristics. This p-n diode could perform a crucial role in the development of optoelectronic valleytronic devices.

Case series: conditions inhibiting eruption of permanent first molars

PURPOSE

The purpose of this study was to evaluate the radiological and histopathological findings of 11 patients with unerupted first molars to verify the factors obstructing spontaneous eruption.

METHODS

The patients' clinical, radiological, and histopathological data were evaluated retrospectively to determine histopathological diagnosis, radiographic findings, methods of surgical management, and postoperative course.

RESULTS

This study involved 4 male and 7 female patients (mean age=9.5 years old). Nine cases involved the mandible. The patients' histopathological diagnoses included 3 odontogenic tumors, 2 odontogenic cysts, and 6 hyperplastic dental follicles. Radiographically, 10 cases showed characterless enlargement of the follicular space, while only 1 displayed radiopaque bodies. One patient with a tumor underwent enucleation, and 1 with a cyst underwent cystectomy and tooth extraction. The others underwent wide excision or partial excision of the surrounding tissue at the top of the impacted tooth. Tumor relapse was observed in 3 cases.

CONCLUSION

Surgeons should perform aggressive treatment for patients with unerupted teeth because spontaneous eruption is rare in cases involving non-neoplastic lesions such as hyperplastic dental follicles.

Magnetic resonance imaging (MRI) and dynamic MRI evaluation of extranodal non-Hodgkin lymphoma in oral and maxillofacial regions

OBJECTIVE

The purpose of this study was to evaluate the diagnostic value of magnetic resonance imaging (MRI), especially dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), in extranodal non-Hodgkin lymphoma (NHL) of oral and maxillofacial regions.

STUDY DESIGN

Thirteen cases with extranodal NHL were examined using MRI. T1-weighted images (T1WI) and T2-weighted images (T2WI) or short TI inversion recovery (STIR) images were obtained in all cases. Contrast-enhanced images and DCE-MRI were acquired in 10 and 7 cases, respectively. On DCE-MRIs, we analyzed the parameters as follows: contrast index at maximal contrast enhancement (CImax), maximum contrast index (CI) gain/CImax ratio, and washout ratios (WR(300), WR(600), and WR(900)) at 300, 600, and 900 seconds after contrast medium injection.

RESULTS

The signal intensity of all lesions was hypointense to isointense on T1WIs and showed variable contrast enhancement patterns. On T2WIs and STIR images, the signal intensity was isointense to hyperintense in almost all cases. Analysis of DCE-MRI parameters in extranodal NHLs resulted in the identification of 4 types of CI curves according to CImax and WR: (1) CImax greater than 2.0 and WR(900) greater than 40%, (2) CImax greater than 2.0 and WR(900) less than 40%, (3) CImax less than 1.5 and WR(900) greater than 40%, and (4) CImax less than 1.5 and WR(900) greater than 40%.

CONCLUSIONS

The signal intensities on MRI were not specific to extranodal NHL and resembled those of other tumor types. When CImax was less than 1.5 or WR900 was less than 40%, these parameters contributed to diagnosis in extranodal NHLs.

Two-piece customized mold technique for high-dose-rate brachytherapy on cancers of the buccal mucosa and lip

OBJECTIVE

High-dose-rate (HDR) brachytherapy using a customized mold is a minimally invasive treatment for oral cancer; however, it is difficult to use this technique for buccal and lip cancers involving the commissura labiorum, owing to its anatomic form. The purpose of this study was to introduce an improved customized mold consisting of 2 pieces to allow the fixation of molds to these sites.

STUDY DESIGN

Five patients with buccal carcinoma and 1 patient with lip carcinoma were treated with this technique after external beam radiotherapy. One patient with neck metastasis underwent both neck dissection and partial tumor resection before HDR brachytherapy.

RESULTS

At the end of the follow-up period, 5 patients had no tumor recurrence, and 1 patient had suffered local recurrence.

CONCLUSIONS

Our technique is a viable therapeutic option for patients with buccal and lip carcinomas for whom the therapeutic modalities are limited by age, performance status, and other factors.

Usefulness of MRI and dynamic contrast-enhanced MRI for differential diagnosis of simple bone cysts from true cysts in the jaw

INTRODUCTION

It can be difficult to differentiate simple bone cysts (SBCs) from true cysts in the jaw when these lesions appear unilocular. The present study reports the MR imaging of subjects with SBCs and describes the diagnostic value of the MRI findings.

MATERIALS AND METHODS

Ten subjects with SBCs in the jaw were examined using MRI. T1- and T2-weighted images (T1WI, T2WI) were obtained, and contrast-enhanced images and dynamic contrast-enhanced MRI (DCE-MRI) were acquired.

RESULTS

In all cases, the contrast-enhanced T1WI acquired approximately 6 minutes after the administration of Gd-DTPA showed marked enhancement of the margin and slight enhancement of the inner part of the cyst cavity. In all cases, the time-signal intensity (SI) curves show a gradual increase in the SI until approximately 15 minutes after the administration of Gd-DTPA. These findings might not be observed on the DCE-MRIs of the other true cysts with epithelial lining that show no enhancement in a cavity.

CONCLUSION

MRI, especially DCE-MRI, can provide useful information for distinguishing SBCs from other cysts.

Polarization reversal in multiferroic TbMnO3 with a rotating magnetic field direction

For the memory application of magnetoelectric multiferroics, not only bistability (i.e., ferroelectricity) but also the switching of the polarization direction with some noneverlasting stimulus is necessary. Here, we report a novel method for the electric polarization reversal in TbMnO3 without the application of an electric field or heat. The direction of the magnetic-field-induced polarization along the a axis (Pa) is memorized even in the zero field where Pa is absent. The polarization direction can be reversed by rotating the magnetic-field direction in the ab plane.

Condylar luxation following bilateral intraoral vertical ramus osteotomy

OBJECTIVE

The intraoral vertical ramus osteotomy (IVRO) is widely used to treat mandibular prognathism and some forms of temporomandibular joint disorder (TMD). This retrospective report evaluated the incidence of condylar luxation following bilateral IVRO.

STUDY DESIGN

Clinical records and radiographs of 319 patients seen during a 13-year period between 1992 and 2005 were evaluated. The mean age of the patients (232 females, 87 males) at the time of surgical procedure was 26.1 years. All patients underwent a bilateral IVRO to treat mandibular prognathism or TMD. Postoperatively, the condylar position was evaluated from lateral and anteroposterior cephalograms and tomograms of the temporomandibular joint (TMJ).

RESULTS

An IVRO was performed on 638 sides in 319 patients. In 8 sides in 8 patients, the proximal segments were dislocated, and the condylar heads were located beyond the articular eminence. One patient underwent a closed reduction under local anesthesia, and 4 patients underwent an open reduction under sedation or general anesthesia. The average follow-up period was 4.3 years (1.2-9 years). Six of the 8 patients did not complain of any TMJ dysfunction. The objective clinical evaluation also did not reveal any dysfunctional patterns. A TMJ click on the affected side was observed in 1 patient, and mandibular deviation to the affected side upon opening the mouth was observed in 1 patient.

CONCLUSION

Although condylar sag is a consistent finding after IVRO, the mandibular condyles tend to return their preoperative positions. In this study, condylar luxation was observed in 1.3% (8/638) of the joints after bilateral IVRO. However, there were no severe clinical problems in these patients during a relatively long follow-up period.

In-crystal and surface charge transport of electric-field-induced carriers in organic single-crystal semiconductors

Gate-voltage dependence of carrier mobility is measured in high-performance field-effect transistors of rubrene single crystals by simultaneous detection of the longitudinal conductivity sigma(square) and Hall coefficient R(H). The Hall mobility mu(H) (identical with sigma(square)R(H)) reaches nearly 10 cm(2)/V s when relatively low-density carriers (<10(11) cm(-2)) distribute into the crystal. mu(H) rapidly decreases with higher-density carriers as they are essentially confined to the surface and are subjected to randomness of the amorphous gate insulators. The mechanism to realize high carrier mobility in the organic transistor devices involves intrinsic-semiconductor character of the high-purity organic crystals and diffusive bandlike carrier transport in the bulk.

Overcorrection in vertical alveolar distraction osteogenesis for dental implants

A decrease in bone height following alveolar distraction osteogenesis (DO) before implant placement is common, and can be severe when alveolar DO is performed soon after surgical intervention. The aim of this study was to investigate the decrease in bone height after vertical alveolar DO and determine the need for overcorrection with implant placement. Thirty-five patients (17 males and 18 females, mean age 43.9 years) underwent 38 procedures with successful placement of 141 dental implants. Alveolar ridge height was evaluated using digital orthopantomographic radiographs taken shortly after the end of distraction, at consolidation and before implant placement. The mean distraction was 9.7 mm. The total vertical alveolar bone decrease was 2.1mm (21%) during the consolidation period and 3.6mm (37%) at implant placement. Although the 20 sites with a healthy alveolus (surgery >6 months) had bone reductions of 1.5 and 2.5mm (15 and 25%) the 18 sites at which alveolar DO was performed within 6 months (mean 3.0) of surgical intervention had much greater bone loss of 2.7 and 4.8mm (28 and 50%), respectively ((**)P<0.01). These results indicate that any alveolar DO protocol should include a waiting period after the surgical intervention, as well as consider an overcorrection of more than 25% within the limits of the applied surgical protocol.

[A case of metastatic lung cancer responding well from tongue carcinoma using a combination of stereotactic radiation therapy and docetaxel/cisplatin/5-FU chemotherapy]

A 53-year-old man underwent partial glossectomy for tongue cancer on the right side (well-differentiated squamous cell carcinoma T 1 N 0 M 0). One and 9 months later, cervical lymph node metastasis was observed bilaterally. After bilateral radical neck dissection, 2 courses of NDP/5-FU combined chemotherapy were administered. However, 2 metastatic lung cancers were observed 14 months after initial treatment. Stereotactic radiation therapy of 50 Gy in 5 fractions and 6 courses of docetaxel/cisplatin/5-FU chemotherapy were administered. As a result, no recurrence was observed, and a complete response was obtained for 41 months after lung metastasis.

Mandibular reconstruction using intraoral trifocal bone transport: report of a case

On the mandibular reconstruction after tumor resection, it is easy to achieve esthetic and functional results when mandibular defect is relative small, however, it is difficult to reconstruct adequately larger defected mandible. Recently, with progress of devices, distraction osteogenesis that is the method of tissue regeneration is used as mandibular reconstruction. A 19-year-old male patient presented complaining of right lower jaw swelling. Biopsy suspected a multiple-cystic ameloblastoma in mandible. Under the general anesthesia, a mandibulectomy was performed from the right side ramus to the left side incisor. A mandibular reconstruction plate was attached to the proximal and distal bone segments. 2 types of intraoral distraction devices were placed inside the plate. These devices had 25 mm and 60 mm distraction length. After 9 days of latency, trifocal bone transport was started by 0.5 mm 2 times activation per day. After consolidation for 23 weeks, reconstruction plate and distraction devices were removed. 2.5 m x 2.0 cm iliac bone and cancellous bone were placed in the docking site with platelet rich plasma. The mandibular defect (85 mm) was reconstructed adequately using intraoral distraction osteogenesis trifocal bone transport technique. Symmetric facial balance was achieved. Now there is no recurrence and dental implants were placed on new bone.

Ferroelectric polarization flop in a frustrated magnet MnWO4 induced by a magnetic field

The relationship between magnetic order and ferroelectric properties has been investigated for MnWO4 with a long-wavelength magnetic structure. Spontaneous electric polarization is observed in an elliptical spiral spin phase. The magnetic-field dependence of electric polarization indicates that the noncollinear spin configuration plays a key role for the appearance of the ferroelectric phase. An electric polarization flop from the b direction to the a direction has been observed when a magnetic field above 10 T is applied along the b axis. This result demonstrates that an electric polarization flop can be induced by a magnetic field in a simple system without rare-earth 4f moments.

Large optical nonlinearity of semiconducting single-walled carbon nanotubes under resonant excitations

We measured third-order nonlinear susceptibility (chi(3)) spectra in semiconducting single-walled carbon nanotubes (SWNTs) by the Z-scan method. |Imchi(3)| is remarkably enhanced under resonant excitation to the lowest interband transition, reaching 4.2 x 10(-6) esu and 1.5 x 10(-7) esu in SWNTs grown by the laser ablation and HiPco methods, respectively. A comparison of the transient absorption changes evaluated by degenerate and nondegenerate pump-probe measurements suggests that the resonant enhancement of |Imchi(3)| is dominated by a coherent process rather than by saturation of absorption.

Control of carrier density by self-assembled monolayers in organic field-effect transistors

Organic thin-film transistors are attracting a great deal of attention due to the relatively high field-effect mobility in several organic materials. In these organic semiconductors, however, researchers have not established a reliable method of doping at a very low density level, although this has been crucial for the technological development of inorganic semiconductors. In the field-effect device structures, the conduction channel exists at the interface between organic thin films and SiO(2) gate insulators. Here, we discuss a new technique that enables us to control the charge density in the channel by using organosilane self-assembled monolayers (SAMs) on SiO(2) gate insulators. SAMs with fluorine and amino groups have been shown to accumulate holes and electrons, respectively, in the transistor channel: these properties are understood in terms of the effects of electric dipoles of the SAMs molecules, and weak charge transfer between organic films and SAMs.

Development of p53 protein transduction therapy using membrane-permeable peptides and the application to oral cancer cells

Recent studies suggest that several proteins can transverse biological membranes through protein transduction. The protein transduction domains of these proteins, 10-16 residues long, have been identified as critical domains for the protein transduction. Poly-arginine peptide also has the ability of protein transduction. Here, we show that the protein delivery system using 11 poly-arginine peptides (11R) is a powerful tool for the transduction of the biologically active tumor suppressor protein, p53, to suppress the proliferation of oral cancer cells. The 11R-fused p53 proteins (11R-p53) effectively penetrated across the plasma membrane of the cancer cells and translocated into the nucleus. The proteins induced the activity of the p21/WAF promoter and inhibited the proliferation of human oral cancer cells, in which the p53 gene was mutated. The effect was equivalent to that of the adenovirus-mediated p53 gene transduction system. Moreover, 11R-p53 enhanced the cisplatin-dependent induction of apoptosis of the cells. These data suggest that this protein transduction method may become a promising cancer therapy.

Evidence for insulating behavior in the electric conduction of (NH(3))K(3)C(60) systems

Microwave study using the cavity perturbation technique revealed that the conductivity of the antiferromagnet (NH(3))K(3-x)Rb(x)C(60) at 200 K is already 3-4 orders of magnitude smaller than those of superconductors, K(3)C(60) and (NH(3))(x)NaRb(2)C(60), and that the antiferromagnetic compounds are insulators below 250 K without metal-insulator transitions. The striking difference in the magnitude of the conductivity between these materials strongly suggests that the Mott-Hubbard transition in the ammoniated alkali fullerides is driven by a reduction of lattice symmetry from face-centered-cubic to face-centered-orthorhombic, rather than by the magnetic ordering.

Modified sagittal split ramus osteotomy with a reciprocating saw and new retractors

Modified sagittal split ramus osteotomy with new instruments and a reciprocating saw is reported. With this modification, the sagittal separation of the ramus is performed by the reciprocating saw with an original wide-blade buccal retractor and a new lingual retractor, instead of the traditional channeled retractor. The wide-blade retractor is inserted to the buccal aspect of the mandibular ramus, which ensures protection from instrumental injury to the adjacent soft tissues and vessels, and the new lingual retractor, instead of the channeled retractor, is inserted to the lingual aspect of the ramus. The osteotomy line follows that of Dal Pont's modification. Close attention must be paid to the direction of the saw blade. The separated bone plane should be located in the external cortical bone layer of the ramus, so as to avoid injury of the inferior alveolar neurovascular bundle. The osteotomy is completed with the smooth osteotomized interface, which facilitates positioning of the bone segments by the surgeon. The new instruments and the reciprocating saw may provide safe and rapid sagittal split ramus osteotomy.

Antiferromagnetism and phase diagram in ammoniated alkali fulleride salts

Intercalation of neutral ammonia molecules into trivalent face-centered-cubic (fcc) fulleride superconductors induces a dramatic change in electronic states. Monoammoniated alkali fulleride salts (NH3)K3-xRbxC60, forming an isostructural orthorhombic series, undergo an antiferromagnetic transition, which was found by the electron spin resonance experiment. The Neel temperature first increases with the interfullerene spacing and then decreases for (NH3)Rb3C60, forming a maximum at 76 K. This feature is explained by the generalized phase diagram of Mott-Hubbard transition with an antiferromagnetic ground state.