Visualization of airborne droplets generated with dental handpieces and verification of the efficacy of high-volume evacuators: an in vitro study.

BACKGROUND: The COVID-19 pandemic led to concerns about the potential airborne transmission of the virus during dental procedures, but evidence of actual transmission in clinical settings was lacking. This study aimed to observe the behavior of dental sprays generated from dental rotary handpieces and to evaluate the effectiveness of high-volume evacuators (HVEs) using laser light sheets and water-sensitive papers. METHODS: A dental manikin and jaw model were mounted in a dental treatment unit. Mock cutting procedures were performed on an artificial tooth on the maxillary left central incisor using an air turbine, a contra-angle electric micromotor (EM), and a 1:5 speed-up contra-angle EM (×5EM). Intraoral vacuum and extraoral vacuum (EOV) were used to verify the effectiveness of the HVEs. The dynamics and dispersal range of the dental sprays were visualized using a laser light sheet. In addition, environmental surface pollution was monitored three-dimensionally using water-sensitive papers. RESULTS: Although the HVEs were effective in both the tests, the use of EOV alone increased vertical dispersal and pollution. CONCLUSIONS: The use of various types of HVEs to reduce the exposure of operators and assistants to dental sprays when using dental rotary cutting instruments is beneficial. The study findings will be helpful in the event of a future pandemic caused by an emerging or re-emerging infectious disease.

Histopathological findings affect quantitative values of single photon emission computed tomography in patients with antiresorptive agent-related osteonecrosis of the jaws.

Objectives: This study investigated the relationships between quantitative values calculated from bone single photon emission computed tomography/computed tomography (SPECT/CT) images and histopathological findings observed in surgical specimens from patients with antiresorptive agent-related osteonecrosis of the jaw (ARONJ); it sought to clarify histopathological factors that cause accumulation in bone SPECT/CT images of patients with ARONJ. Methods: This study included 81 pathological specimens of 21 lesions obtained from 18 patients with ARONJ who underwent SPECT/CT and jaw resection. The maximum standardized uptake value (SUVmax) of each volume of interest of the specimens was calculated using RAVAT® software. The ratio of the SUVmax to the mean value of SUVmax in temporal bone was termed rSUVmax. The rSUVmax and pathological findings (sequestration, degree of fibrosis, degree of trabecular bone destruction, degree of inflammatory cell infiltration, and vascularity) were compared using the Mann-Whitney U test and the Kruskal-Wallis test. Results: In univariate analysis with rSUVmax as the dependent variable, the pathological findings of sequestration (P=0.058), degree of fibrosis (P=0.810), degree of trabecular bone destruction (P=0.237), degree of inflammatory cell infiltration (P=0.120), and vascularity (P=0.111) showed no significant difference among the groups for each variable. Conclusions: We found no association between quantitative values in bone SPECT/CT and histological changes in ARONJ, probably because bone SPECT/CT has limited spatial resolution. Limitations of this study may include the imaging findings of a decrease in tracer accumulation because of an involucrum of necrosed bone, various histopathological findings in ARONJ, and failure to consider the effect of preoperative anti-inflammatory treatment.

Evaluation of Velopharyngeal Closure Function With 4-Dimensional Computed Tomography and Assessment of Radiation Exposure in Pediatric Patients: A Cross-Sectional Study.

OBJECTIVE: Some patients with cleft palate (CP) need secondary surgery to improve functionality. Although 4-dimensional assessment of velopharyngeal closure function (VPF) in patients with CP using computed tomography (CT) has been existed, the knowledge about quantitative evaluation and radiation exposure dose is limited. We performed a qualitative and quantitative assessment of VPF using CT and estimated the exposure doses. DESIGN: Cross-sectional. SETTING: Computed tomography images from 5 preoperative patients with submucous CP (SMCP) and 10 postoperative patients with a history of CP (8 boys and 7 girls, aged 4-7 years) were evaluated. PATIENTS: Five patients had undergone primary surgery for SMCP; 10 received secondary surgery for hypernasality. MAIN OUTCOME MEASURES: The presence of velopharyngeal insufficiency (VPI), patterns of velopharyngeal closure (VPC), and cross-sectional area (CSA) of VPI was evaluated via CT findings. Organ-absorbed radiation doses were estimated in 5 of 15 patients. The differences between cleft type and VPI, VPC patterns, and CSA of VPI were evaluated. RESULTS: All patients had VPI. The VPC patterns (SMCP/CP) were evaluated as coronal (1/4), sagittal (0/1), circular (1/2), and circular with Passavant's ridge (2/2); 2 patients (1/1) were unevaluable because of poor VPF. The CSA of VPI was statistically larger in the SMCP group (P = .0027). The organ-absorbed radiation doses were relatively lower than those previously reported. CONCLUSIONS: Four-dimensional CT can provide the detailed findings of VPF that are not possible with conventional CT, and the exposure dose was considered medically acceptable.

Effect of morphological findings in computed tomography on the quantitative values in single-photon emission computed tomography for patients with antiresorptive agent-related osteonecrosis of the jaw: a cross-sectional study.

OBJECTIVE: Quantitative analyses of gamma-ray accumulation in single-photon emission computed tomography (SPECT), and the evaluation of antiresorptive agent-related osteonecrosis of the jaw (ARONJ) have been reported recently. However, the relationship between the quantitative parameters calculated from SPECT and the detailed morphological changes observed in computed tomography (CT) remains unclear. This study aimed to investigate patients' characteristics and morphological changes observed on CT, and their effects on the quantitative values in SPECT. METHODS: From April 2017 to March 2019, patients diagnosed with ARONJ at our hospital were enrolled. The data obtained before September 2017 were reviewed retrospectively, and other data were collected prospectively. CT scans were evaluated for internal texture, sequestrum formation, periosteal reaction, cortical perforation, bone expansion, and pathological fracture. For quantitative assessment, the ratio of the maximum standardized uptake value (SUV) to the mean SUV in the temporal bone (rSUVmax) was calculated from SPECT images. The factors affecting rSUVmax were investigated by multiple regression analysis. The statistical significance level was set at α = 0.05. RESULTS: Overall, 55 lesions of 42 patients (median age and interquartile range, 75 [67-80 years], 27 female) were evaluated. Male sex (p = 0.007) and bilateral location (p < 0.0001) were selected as variables in the multivariate analysis. Adjusted coefficient of determination R2 was 0.59 (p < 0.0001). CONCLUSION: Sex and horizontal progression of the disease may affect individually calibrated SUVs in SPECT for patients with ARONJ.

Quantitative evaluation of anti-resorptive agent-related osteonecrosis of the jaw using bone single photon emission computed tomography in clinical settings: relationship between clinical stage and imaging.

OBJECTIVE: This study aimed to use quantitative values, calculated from bone single photon emission computed tomography (SPECT) imaging, to estimate the reliability of progression evaluation for anti-resorptive agent-related osteonecrosis of the jaw (ARONJ). METHODS: The study population consisted of 21 patients (23 lesions), clinically diagnosed with mandibular ARONJ, who underwent SPECT/CT scanning. Diagnosis and staging of ARONJ were performed according to the American Association of Oral and Maxillofacial Surgeons (AAOMS) definition and the recommendations of the International Task Force on ONJ. Hybrid SPECT/CT imaging quantitative analyses were performed on a workstation. Each volume of interest (VOI) was semi-automatically placed over a lesion with areas of high tracer accumulation, using the GI-BONE® software default threshold method settings. Additionally, control VOI was manually set over an unaffected area. Measured parameters included standardized uptake values (SUV)-maximum (SUVmax) and mean (SUVmean), metabolic bone volume (MBV)-the total volume above the threshold, and total bone uptake (TBU) as calculated by MBV × SUVmean. We also calculated the SUV ratio (rSUV) between the lesion and control area, factoring for differences in individual bone metabolism; the ratios were termed rSUVmax and rSUVmean, accordingly. The product of multiplying the rSUVmean by MBV of a lesion was defined as the ratio of TBU (rTBU). Quantitative values were compared between clinical stages by the Kruskal-Wallis test and subsequent post hoc analysis. RESULTS: MBVs (cm3) were: median, [IQR] Stage 1, 8.28 [5.62-9.49]; Stage 2, 15.28 [10.64-24.78]; and Stage 3, 34.61 [29.50-40.78]. MBV tended to increase with stage increase. Furthermore, only MBV showed a significant difference between clinical stages (p < 0.01). Subsequent post hoc analysis showed no significant difference between stages 1 and 2 (p = 0.12) but a significant difference between stages 2 and 3 (p = 0.048). rSUVmax and rTBU tended to increase with stage increase, but the differences between the stages were not significant (p = 0.10 and p = 0.055, respectively). CONCLUSION: MBV, which includes the concept of volume, showed significant differences between clinical stages and tended to increase with the stage increase. As an objective and reliable indicator, MBV might be an adjunct diagnostic method for staging ARONJ.

Velopharyngeal closure analysis using four-dimensional computed tomography: a pilot study of healthy volunteers and adult patients with cleft palate.

BACKGROUND: Nasopharyngoscopy is a common method to evaluate velopharyngeal closure in patients with cleft palate. However, insertion of a fiberoptic nasopharyngoscope causes discomfort in patients. The aim of this study was to estimate the reliability of short-time exposure images obtained using 320-row area detector computed tomography (320-ADCT) as a novel evaluation method for the assessment of velopharyngeal function. METHODS: We evaluated five healthy adult volunteers and five postoperative adult patients with cleft palate. During a 3.3-s imaging exposure, the participants were asked to perform two tasks: nasal inspiration and subsequent oral expiration through a catheter into a water-filled cup. The movement of the velopharyngeal structures was recorded during each examination, and the presence of velopharyngeal insufficiency (VPI) and velopharyngeal closure (VPC) patterns were estimated. If VPI was detected, the cross-sectional area was also calculated. Cohen's kappa and weighted kappa coefficients were used to evaluate the concordance of nasopharyngoscopy and 320-ADCT evaluation. RESULTS: Speech pathology evaluation did not reveal hypernasality in any study participant. Micro-VPI was detected by nasopharyngoscopy in one healthy volunteer and two patients. 320-ADCT detected micro-VPI in two more patients. The cross-sectional area of the VPI in these subjects ranged from 2.53 to 16.28 mm2. Nasopharyngoscopy and 320-ADCT were concordant in detecting VPI in eight participants (κ = 0.6) and in assessing VPC patterns in nine (κ = 0.82). Moreover, images obtained using 320-ADCT allowed for reduced dead angle and, thus, easy detection of micro-VPI and Passavant's ridges. CONCLUSION: Although the radiation exposure cannot be ignored, our novel evaluation method using 320-ADCT enables more detailed evaluation of VPC than nasopharyngoscopy. Future studies should investigate the relationship between 320-ADCT findings and speech pathology evaluations.

Safety and efficacy of adzuki bean extract in subjects with moderate to high LDL-C: a randomized trial.

The safety and efficacy of polyphenol-containing adzuki bean extract on lipid metabolism were evaluated in human subjects in an 8-week, randomized, double-blind, placebo-controlled, parallel intervention study. No adverse effects were observed in the participants receiving adzuki bean extract. The adzuki bean group showed a significant increase in the ΔHDL-C concentration compared with the placebo group after 4 weeks of intervention (3.76 ± 7.79 mg/dL vs. -0.08 ± 6.03 mg/dL), respectively, and both groups showed reduced ∆HDL-C concentrations, with the adzuki bean extract group showing a return to the baseline levels (0.36 ± 5.36 mg/dL) and the placebo group showing a decrease to below the baseline levels (-3.17 ± 7.79 mg/dL) at week 8. This short-term study represents the first step in establishing the practicality, safety, and plausibility of HDL-C maintaining effects of adzuki bean extract in human subjects.

Clinical evaluation of postoperative nausea and vomiting after cleft lip and/or palate surgery in pediatric patients. Part 2: evaluation of preventive administration of droperidol in combination with dexamethasone.

OBJECTIVES: This study aimed to evaluate the effect of preventive administration of the combination of droperidol and dexamethasone on lowering the risk for postoperative nausea and vomiting (PONV) after cleft-related surgery in pediatric patients. METHODS: Preventive care consisted of a single dose of droperidol (0.025 mg/kg) and dexamethasone (0.06 mg/kg), which were administered at the end of surgery. The effect of preventive administration was evaluated in a sample group of 58 patients aged ≥3 years who underwent cleft-related surgery. Thirty patients received preventive administration (prevention group) and 28 patients did not (comparative group). The following outcome variables were evaluated between the groups: sex, age, body weight at the time of surgery, and duration of anesthesia. The presence or absence of PONV was the primary outcome and other variables were considered as explanatory variables. RESULTS: The incidence rate of PONV was 20% (6/30) in the prevention group and 28.6% (8/28) in the comparative group, with no significant difference between the groups (p=0.45). In multiple logistic regression analysis, sex was the only explanatory factor of PONV, with a higher risk in girls than in boys (odds ratio, 6.20; 95% confidence interval, 1.65-27.63; p=0.01). CONCLUSIONS: The incidence rate of PONV is 20% with preventive care of droperidol and dexamethasone administration, but this rate is not different from that without this combination. Sex is a risk factor for PONV. Further studies are required to validate our results.

Osteogenesis Imperfecta Diagnosed from Mandibular and Lower Limb Fractures: A Case Report.

Osteogenesis imperfecta (OI) is a congenital disease characterized by bone fragility and low bone mass. Despite the variety of its manifestation and severity, facial fractures occur very infrequently. Here, we report a case of an infant diagnosed with OI after mandibular and lower limb fractures. A boy aged 1 year and 3 months was brought to his neighboring hospital with a complaint of facial injury. He was transferred to our hospital to undergo operation 3 days later. Computed tomography images revealed multiple mandibular fractures including complete fracture in the symphysis and dislocated condylar fracture on the right side. Open reduction and internal fixation with absorbable implants was performed 7 days after injury. He fractured his right lower limb 2 months later. He was diagnosed with OI type IA by an orthopedist. He will be administered bone-modifying agents if he suffers from frequent fractures.

Appropriate Tongue Blade Length of the Dingman Mouth Gag for Japanese Pediatric Patients With Cleft Palate and Mandibular Micrognathia.

Objective Our objective is to determine appropriate specifications for smaller tongue blade for Japanese pediatric patients with cleft palate (CP) and mandibular micrognathia. Patients We investigated 59 patients who underwent palatoplasty. Patients were divided into two groups: the micrognathia (MG) group consisted of 11 patients and the normognathia (NG) group consisted of 48 patients. Interventions The following five items were investigated retrospectively: (1) gender, (2) cleft type, (3) age at the time of surgery, (4) weight at the time of surgery, and (5) distance from the tongue blade base to the posterior pharyngeal wall (Dis). Results There was a significant difference (P < .01) in age at the time of surgery and in Dis between groups, but not in weight. The minimum values were 55 mm for the MG group. As for correlations between age and weight at the time of surgery, the P values for the MG and NG groups were .993 and .052, respectively. As for correlations between weight at the time of surgery and Dis, the P values for the MG and NG groups were .987 and .099, respectively. Conclusions It was difficult to predict Dis on the basis of the patient's age and weight measured preoperatively. The minimum Dis was 55 mm, equal to the length from the base to the tip of the Dingman Mouth Gag tongue blade currently in use, suggesting that a tongue blade of approximately 50 mm in length, shorter than the current minimum specifications, may be appropriate.

Local recurrence of sclerosing mucoepidermoid carcinoma with eosinophilia in the upper lip: a case report.

INTRODUCTION: Sclerosing mucoepidermoid carcinoma with eosinophilia is a rare morphological variant of thyroid carcinoma associated with Hashimoto's disease. To date, only three such tumors have been reported in the minor salivary glands. We describe the first case, to the best of our knowledge, of recurrent sclerosing mucoepidermoid carcinoma with eosinophilia in the minor salivary glands of the upper lip. CASE PRESENTATION: A 61-year-old Japanese man was referred to our hospital with a mass in his median upper lip of four years' duration. An examination of his median upper lip revealed a well-defined tumor measuring 9 × 12 mm in diameter, which was subsequently resected. Three years after the first surgery, the tumor recurred and was resected. Both tumors were confirmed by histopathology to be sclerosing mucoepidermoid carcinoma with eosinophilia. Neither recurrence nor metastasis was observed in three and a half years of follow-up after the second surgery. CONCLUSION: Our findings indicate that sclerosing mucoepidermoid carcinoma with eosinophilia can originate in the minor salivary glands and may be clinically or pathologically misdiagnosed as other conditions.

Computational analysis suggests that alternative first exons are involved in tissue-specific transcription in rice (Oryza sativa).

MOTIVATION: Transcription start site selection and alternative splicing greatly contribute to diversifying gene expression. Recent studies have revealed the existence of alternative first exons, but most have involved mammalian genes, and as yet the regulation of usage of alternative first exons has not been clarified, especially in plants. RESULTS: We systematically identified putative alternative first exon transcripts in rice, verified the candidates using RT-PCR, and searched for the promoter elements that might regulate the alternative first exons. As a result, we detected a number of unreported alternative first exons, some of which are regulated in a tissue-specific manner. SUPPLEMENTARY INFORMATION: http://www.bioinfo.sfc.keio.ac.jp/research/intron.

Effects of various thiol molecules added on morphology of dendrimer-gold nanocomposites.

Interactions between poly(amidoamine) dendrimer (PAMAM)-gold nanocomposites and alkanethiols and between the former nanocomposites and thiol-modified poly(amidoamine) dendrons in ethyl acetate were investigated by adding alkanethiols, such as 1-propanethiol and 1,3-propanedithiol, and thiol-modified poly(amidoamine) dendrons, generations 0.5 and 2.5 (G0.5-SH and G2.5-SH). The PAMAM dendrimers with surface methyl ester groups used were generations 1.5 and 5.5 (G1.5 and G5.5). The mean particle sizes of PAMAM-gold nanocomposites were about 2.1 for G1.5 and 2.4 nm for G5.5. In both nanocomposite systems where 1-propanethiol and 1,3-propanedithiol were added, the mean particle size was about 4 nm, twice that of the systems where these thiols were not added. Increasing the addition of 1,3-propanedithiol made the average particle size smaller for both nanocomposites systems. To compare with alkanethiol, thiol-modified poly(amidoamine) dendron with a highly branched structure on one side was synthesized. Using G2.5-SH as a protective agent, dendron-gold nanocomposites with mean diameters of 3 to 4 nm were obtained. The difference in particle size was seen only when the combination of PAMAM-gold nanocomposites and thiol-modified dendron was less sterically dense, modified dendron (G0.5-SH). The mechanisms for morphology changes in the dendrimer-gold nanocomposites by the addition of these thiols are discussed.