Effects of adenoid hypertrophy on nasopharyngeal airway ventilation: A computational fluid dynamics study.

OBJECTIVES: Adenoid hypertrophy causes impaired nasopharyngeal airways (NA) ventilation. However, it is difficult to evaluate the ventilatory conditions of NA. Therefore, this study aimed to analyze the nasopharyngeal airway resistance (NARES) based on computational fluid dynamics simulations and the nasopharyngeal airway depth (NAD) and adenoid hypertrophy grade measured on cephalometric cone-beam computed tomography images and determine the relationship between NAD and grade and NARES to ultimately assess using cephalometric measurements whether NA has airway obstruction defects. METHODS: Cephalogram images were generated from cone-beam computed tomography data of 102 children (41 boys; mean age: 9.14 ± 1.43 years) who received orthodontic examinations at an orthodontic clinic from September 2012 to March 2023, and NAD and adenoid grade and NARES values were measured based on computational fluid dynamics analyses using a 3D NA model. Nonlinear regression analyses were used to evaluate the relationship between NARES and NAD and correlation coefficients to evaluate the relationship between grade and NARES. RESULTS: NARES was inversely proportional to the cube of NAD (R2 = 0.786, P < 0.001), indicating a significant relationship between these variables. The resistance NARES increased substantially when the distance NAD was less than 5 mm. However, adenoid Grade 4 (75 % hypertrophy) was widely distributed. CONCLUSIONS: These study findings demonstrate that the ventilatory conditions of NA can be determined based on a simple evaluation of cephalogram images. An NAD of less than 5 mm on cephalometric images results in NA obstruction with substantially increased airflow resistance.

Does rapid maxillary expansion improve nasal airway obstruction? A computer fluid dynamics study in patients with nasal mucosa hypertrophy and obstructive adenoids.

INTRODUCTION: Rapid maxillary expansion (RME) expands the maxillary dentition laterally and improves nasal airway obstruction. However, the incidence of nasal airway obstruction improvement after RME is approximately 60%. This study aimed to clarify the beneficial effects of RME on nasal airway obstruction in specific pathologic nasal airway diseases (nasal mucosa hypertrophy and obstructive adenoids) using computer fluid dynamics. METHODS: Sixty subjects (21 boys; mean age 9.1 years) were divided into 3 groups according to their nasal airway condition (control, nasal mucosa hypertrophy, and obstructive adenoids), and those requiring RME had cone-beam computed tomography images taken before and after RME. These data were used to evaluate the nasal airway ventilation condition (pressure) using computer fluid dynamics and measure the cross-sectional area of the nasal airway. RESULTS: The cross-sectional area of the nasal airway significantly increased after RME in all 3 groups. The pressures in the control and nasal mucosa groups significantly reduced after RME but did not change significantly in the adenoid group. The incidence of improvement in nasal airway obstruction in the control, nasal mucosa, and adenoid groups was 90.0%, 31.6%, and 23.1%, respectively. CONCLUSIONS: The incidence of improvement in nasal airway obstruction after RME depends on the nasal airway condition (nasal mucosa hypertrophy and obstructive adenoids). In patients with nonpathologic nasal airway conditions, the obstruction may be sufficiently improved with RME. Furthermore, to some extent, RME may be effective in treating nasal mucosa hypertrophy. However, because of obstructive adenoids, RME was ineffective in patients with nasal airway obstruction.

Comparison of mouth rinsing performance between adults and children using a contactless vital sensing camera.

BACKGROUND: Evaluating mouth rinsing skills is useful for assessing oral function, however current evaluation methods are subjective. OBJECTIVES: This study compared mouth rinsing between adults and children using a contactless camera to capture lip motion. METHODS: The subjects comprised 16 adults and 13 children with no oral dysfunction. A compact vital sensing camera adapted from a Microsoft Xbox One Kinect Sensor® (Kinect) was placed 100 cm from the floor and 120 cm from the subject; 5, 10 and 15 ml of water were used as samples. Participants were instructed to hold the sample in the oral cavity, close the lips and move the sample alternatively left and right for 15 s. Maximum/minimum displacement from the reference plane and rinsing cycle for each sample were analysed by one-way analysis of variance. RESULTS: In adults, there was no significant difference in the maximum/minimum displacement between the left and right sides of the angulus oris due to differences in sample amount. In children, the right maximum significantly differed between the 5- and 15-ml and 10- and 15-ml samples, while the left maximum significantly differed between the 5- and 10-ml and 5- and 15-ml samples. The right minimum significantly differed between the 5- and 10-ml samples, as did the duration of mouth rinsing between the 5- and 15-ml samples. CONCLUSIONS: In children, lip movement and mouth rinsing duration tended to decrease with increasing sample volume. Evaluating lip movement using a contactless vital sensing camera is useful for assessing children's development of oral function.

Factors related to mouth breathing syndrome in preschool children and the effects of incompetent lip seal: An exploratory study.

OBJECTIVES: A set of orofacial signs and symptoms completely or partially present in individuals who replace the correct pattern of nasal breathing with an oral or mixed pattern is defined as mouth breathing syndrome (MBS). In a previous report, it was clarified that an incompetent lip seal (ILS) affected the occurrence of MBS among primary school children. However, the factors related to MBS and the effect of ILS in preschool children remain unclear. The purpose of this study was to clarify the factors relevant to MBS in preschool children and investigate the relationship of ILS to MBS. MATERIAL AND METHODS: We surveyed 285 preschool children between 3 and 5 years of age. Their guardians completed the questionnaire, which consisted of 44 questions regarding the children's daily health conditions and lifestyle habits. To classify the closely related questions into their respective factors and to examine the strength of the correlation between the newly revealed factors, an exploratory factor analysis with promax rotation was performed. RESULTS: The factor analysis identified nine items representing four factors. Factors 1-4 were defined as "diseases of the nose," "ILS," "problem with swallowing and chewing," and "eating and drinking habits," respectively. Factor 2 most strongly correlated with Factor 1, and both Factors showed a relatively strong correlation with Factor 3. CONCLUSIONS: The initial stage of MBS may be present in preschool children. ILS and diseases of the nose can cause poor development of oral functions, such as breathing and eating.

Lip-closing strength in children is enhanced by lip and facial muscle training.

OBJECTIVES: Weakening of lip-closing strength (LCS) associated with an incompetent lip seal (ILS) may affect the oral balance between the lip and tongue pressures. The purpose of this study was to evaluate the effects of lip-closing training in children with lower LCS and/or abnormal habits across different age groups and to compare its effects on increasing LCS in children with malocclusion and/or oral habits. MATERIAL AND METHODS: Lip-closing training was performed by 154 Japanese children aged 3-12 years using a specialized training device at home for 3 months. Children with oral habits and/or exhibiting less than standard LCS were included. LCS was measured using a digital strain force gauge at a dental clinic at the beginning (T0) and after each month (after 3 months: T3). RESULTS: Children had higher LCS responses after lip-closing training. The first month of lip-closing training was more effective than the subsequent months. With lip-closing training, the LCS increased from an average of 6.2 N (T0) to 11.4 N (T3) in Group I, 7.9 N (T0) to 12.8 N (T3) in Group II, and 6.8 N to 11.4 N in Group III. Anterior cross bite, including reverse bite, open bite, and tongue thrusting, significantly reduced training effects. CONCLUSION: Our findings showed that lower LCS in children with ILS resulted in greater responses to lip-closing training in a short period, but oral dysfunction, such as abnormal habits, inhibited the positive effects of training. Our results suggest that less detrimental effects of malocclusion and abnormal oral habits lip-closing training enhances LCS in younger children.

Tissue-Nonspecific Alkaline Phosphatase, a Possible Mediator of Cell Maturation: Towards a New Paradigm.

Alkaline phosphatase (ALP) is a ubiquitous membrane-bound glycoprotein capable of providing inorganic phosphate by catalyzing the hydrolysis of organic phosphate esters, or removing inorganic pyrophosphate that inhibits calcification. In humans, four forms of ALP cDNA have been cloned, among which tissue-nonspecific ALP (TNSALP) (TNSALP) is widely distributed in the liver, bone, and kidney, making it an important marker in clinical and basic research. Interestingly, TNSALP is highly expressed in juvenile cells, such as pluripotent stem cells (i.e., embryonic stem cells and induced pluripotent stem cells (iPSCs)) and somatic stem cells (i.e., neuronal stem cells and bone marrow mesenchymal stem cells). Hypophosphatasia is a genetic disorder causing defects in bone and tooth development as well as neurogenesis. Mutations in the gene coding for TNSALP are thought to be responsible for the abnormalities, suggesting the essential role of TNSALP in these events. Moreover, a reverse-genetics-based study using mice revealed that TNSALP is important in bone and tooth development as well as neurogenesis. However, little is known about the role of TNSALP in the maintenance and differentiation of juvenile cells. Recently, it was reported that cells enriched with TNSALP are more easily reprogrammed into iPSCs than those with less TNSALP. Furthermore, in bone marrow stem cells, ALP could function as a "signal regulator" deciding the fate of these cells. In this review, we summarize the properties of ALP and the background of ALP gene analysis and its manipulation, with a special focus on the potential role of TNSALP in the generation (and possibly maintenance) of juvenile cells.

RNA analysis based on a small number of manually isolated fixed cells (RNA-snMIFxC) to profile stem cells from human deciduous tooth-derived dental pulp cells.

BACKGROUND: Expression of stemness factors, such as octamer-binding transcription factor 3/4 (OCT3/4), sex determining region Y-box 2 (SOX2), and alkaline phosphatase (ALP) in human deciduous tooth-derived dental pulp cells (HDDPCs) can be assessed through fixation and subsequent immuno- or cytochemical staining. Fluorescence-activated cell sorting (FACS), a powerful system to collect cells of interest, is limited by the instrument cost and difficulty in handling. Magnetic-activated cell sorting is inexpensive compared to FACS, but is confined to cells with surface expression of the target molecule. In this study, a simple and inexpensive method was developed for the molecular analysis of immuno- or cytochemically stained cells with intracellular expression of a target molecule, through isolation of a few cells under a dissecting microscope using a mouthpiece-controlled micropipette. RESULTS: Two or more colored cells (~ 10), after staining with a chromogen such a 3,3'-diaminobenzidine, were successfully segregated from unstained cells. Expression of glyceraldehyde 3-phosphate dehydrogenase, a housekeeping gene, was discernible in all samples, while the expression of stemness genes (such as OCT3/4, SOX2, and ALP) was confined to positively stained cells. CONCLUSION: These findings indicate the fidelity of these approaches in profiling cells exhibiting cytoplasmic or nuclear localization of stemness-specific gene products at a small-scale.

Nasal ventilation and rapid maxillary expansion (RME): a randomized trial.

OBJECTIVE: To assess three rapid maxillary expansion (RME) appliances in nasal ventilation. TRIAL DESIGN: Three-arm parallel randomized clinical trial. METHODS: Sixty-six growing subjects (10-16 years old) needing RME as part of their orthodontic treatment were randomly allocated (1:1:1 ratio) to three groups of 22 patients receiving Hyrax (H), Hybrid-Hyrax (HH), or Keles keyless expander (K). The primary outcome of nasal ventilation (pressure and velocity) and secondary outcomes (skeletal, dental, soft tissue, and nasal obstruction changes) were blindly assessed on the initial (T0) and final (T1, 6 months at appliance removal) cone-beam computed tomography (CBCT) data by applying computational fluid dynamics (CFD) method. Differences across groups were assessed with crude and adjusted for baseline values and confounders (gender, age, skeletal maturation, expansion amount, mucosal/adenoid hypertrophy, nasal septum deviation) regression models with alpha = 5%. RESULTS: Fifty-four patients were analysed (19H, 21HH, 14K). RME reduced both nasal pressure (H: -45.8%, HH: -75.5%, K: -63.2%) and velocity (H: -30%, HH: -58.5%, K: -35%) accompanied with nasal obstruction resolution (H: 26%, HH: 62%, K: 50%). Regressions accounting for baseline severity indicated HH expander performing better in terms of post-expansion maximum velocity (P = 0.03) and nasal obstruction resolution (P = 0.04), which was robust to confounders. Mucosal/adenoid hypertrophy and nasal septum deviation changes were variable, minimal, and similar across groups. The HH resulted in significantly greater increase in the nasal cross-sectional area (62.3%), anterior (14.6%), and posterior (10.5%) nasal widths. Nasal obstruction resolution was more probable among younger (P = 0.04), skeletally immature (P = 0.03), and male patients (P = 0.02) without pre-treatment mucosal hypertrophy (P = 0.04), while HH was associated with marginal greater probability for obstruction resolution. CONCLUSIONS: RME resulted in improvement of nasal skeletal parameters and simulated ventilation with the former being in favour of the HH and the latter not showing significant differences among the three appliances. LIMITATION: Attrition in the K group due to blocked activation rods possibly leading to limited sample to identify any existing group differences. HARMS: Replacement of blocked Keles expanders for finalizing treatment. PROTOCOL: The protocol was not published before the trial commencement. REGISTRATION: Australian and New Zealand Clinical Trial Registry; ACTRN12617001136392.

Prevalence of an incompetent lip seal during growth periods throughout Japan: a large-scale, survey-based, cross-sectional study.

BACKGROUND: Systemic and local factors may lead to disruption of craniofacial growth and development, causing an imbalance between the orofacial skeleton, muscle and soft tissue, dental occlusion, and the dental arch during growth periods. We aimed to reveal whether the prevalence of incompetent lip seal (ILS) varies with age and region, as well as to clarify the factors related to an ILS, in a national, large-scale epidemiological study. METHODS: We surveyed 3399 children, from 3 to 12 years of age, visiting 66 pediatric dental clinics throughout Japan. For this survey, we employed a questionnaire consisting of 44 questions regarding daily health conditions and lifestyle habits. We evaluated the differences in ILS prevalence by age and region (using a Cochran-Armitage test for trend and a Kruskal-Wallis test), and the relationship between ILS and factors investigated in the questionnaire (using Spearman's rank correlation coefficient). RESULTS: We observed that 30.7% of Japanese children exhibited an ILS and that the ILS rate increased with age (p < 0.001). There were no regional differences in the rate of ILS in Japanese children (p = 0.506). We revealed that 12 of 44 survey items exhibited a statistically significant correlation with ILS (p < 0.001), using Spearman's rank correlation coefficient. These items involved orofacial morphology, mouth breathing, and possibly, allergic rhinitis. CONCLUSION: The rate of ILS seems to increase with age in children, throughout Japan. Therefore, this disorder may not self-correct during the growth periods in these children. Guidelines are required for pediatric dentists to recognize ILS among children aged 3-12 years.

Incompetent lip seal affects the form of facial soft tissue in preschool children.

Objective: To examine whether incompetent lip seal (ILS) influences the form of facial soft tissue.Methods: Four hundred forty-four preschool children 3-5 years of age were selected. The images of the subjects' facial surface were obtained with a three-dimensional laser scanner. Coordinates of 16 facial landmarks were established and identified on the three-dimensional facial images, and the differences between children with (wILS) and without ILS (woILS) were measured.Results: The angle of sagittal facial convexity, excluding the nose, in 4- and 5-year-old children was significantly smaller in wILS children than in woILS children. The nasal prominence angle and the protrusion angle of lips in wILS children were significantly smaller than those in woILS children, at all ages.Conclusion: Children with ILS have anteriorly prominent subnasales and lips and flatter noses. The influence of ILS on facial form begins to appear even before 3 years of age.

Evaluation of the effect of oral appliance treatment on upper-airway ventilation conditions in obstructive sleep apnea using computational fluid dynamics.

Objective: To evaluate the effect of oral appliance (OA) treatment on upper-airway ventilation conditions in patients with obstructive sleep apnea (OSA) using computational fluid dynamics (CFD).Methods: Fifteen patients received OA treatment and underwent polysomnography (PSG) and computed tomography (CT). CT data were used to reconstruct three-dimensional models of nasal and pharyngeal airways. Airflow velocity and airway pressure measurements at inspiration were simulated using CFD.Results: The apnea-hypopnea index (AHI) improved from 23.1 to 10.1 events/h after OA treatment. On CFD analysis, airflow velocity decreased at the retropalatal and epiglottis-tip levels, while airway pressure decreased at the retropalatal, uvular- and epiglottis-tip levels. The AHI of patients with OSA before OA treatment was correlated with airway pressure at the epiglottis-tip level.Discussion: Treatment with OA improved the ventilation conditions of the pharyngeal airway and AHI. Results of CFD analysis of airway pressure and airflow velocity helped determine the severity and ventilatory impairment site of OSA, respectively.

Effect of adenoids and tonsil tissue on pediatric obstructive sleep apnea severity determined by computational fluid dynamics.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a respiratory disorder caused by the obstruction of the upper airway during sleep. The most common cause of pediatric OSA is adenotonsillar hypertrophy. Adenotonsillectomy is the first-line treatment for pediatric OSA; however, OSA persists in a significant number of patients due, in part, to the method of evaluating enlarged adenoids and tonsil tissue. The reason for these effects on OSA severity is not clear. This study aimed to establish a method to diagnose the need for adenoidectomy or tonsillectomy. METHODS: Twenty-seven Japanese children (mean age 6.6 years) participated in this study, undergoing polysomnography and computed tomography examination. Pharyngeal airway morphology (adenoids and tonsil tissue size, volume, and cross-sectional area [CSA]) and pressure on the upper airway were evaluated at each site using computational fluid dynamic analysis. RESULTS: Apnea-hypopnea index (AHI) showed a strong linear association with maximum negative pressure (Pmax) (AHI = -0.055* events/h Pmax -1.326, R² = .805). The relationship between minimum CSA (CSAmin) and Pmax was represented by an inversely proportional fitted curve (Pmax = -4797/CSAmin -5.1, R² = .507). The relationship between CSAmin and AHI was also represented by an inversely proportional fitted curve (AHI = 301.6 events/h/CSAmin1.22, R² = .680). Pmax greatly increased if CSAmin became ≤ 30 mm². The negative pressure of each site increased when CSA measured ≤ 50 mm². CONCLUSIONS: In children, when the CSA for each site is ≤ 50 mm², AHI is likely to be elevated, and the patient may require tonsillectomy or adenoidectomy.

Antibacterial activity of phellodendron bark against Streptococcus mutans.

Streptococcus mutans is a major cause of tooth decay due to its promotion of biofilm formation and acid production. Several plant extracts have been reported to have multiple biological activities such as anti-inflammation and antibacterial effects. This study investigated the antibacterial activity of three plant extracts, phellodendron bark (PB), yucca, and black ginger, and found that PB had a stronger effect than the other extracts. Then, the minimum inhibitory concentration (MIC) of PB against 100 S. mutans strains was investigated. The MIC range of PB was 9.8-312.5 µg/mL. PB suppressed the growth kinetics of S. mutans in a dose-dependent manner, even at sub-MICs of PB. Then, we investigated the effect of PB on S. mutans virulence. The PB suppressed biofilm formation at high concentrations, although PB did not affect the expression of glucosyltransferase genes. Additionally, PB suppressed the decrease in pH from adding an excess of glucose. The expression of genes responsible for acid production was increased by the addition of excess glucose without PB, whereas their expression levels were not increased in the presence of 1× and 2× MIC of PB. Although PB showed a bacteriostatic effect on planktonic S. mutans cells, it was found that more than 2× MIC of PB showed a partial bactericidal effect on biofilm cells. In conclusion, PB not only showed antibacterial activity against S. mutans but also decreased the cariogenic activity in S. mutans.

Relationship between pharyngeal airway depth and ventilation condition in mandibular setback surgery: A computational fluid dynamics study.

OBJECTIVES: This study aimed to determine the anteroposterior depth (APD) of the pharyngeal airway (PA) where post-operative PA obstruction was predicted, using computer fluid dynamics (CFD), in order to prevent obstructive sleep apnoea after mandibular setback surgery. SETTINGS AND SAMPLE POPULATION: Nineteen skeletal Class III patients (8 men; mean age, 26.7 years) who required mandibular setback surgery had computed tomography images taken before and 6 months after surgery. METHODS: The APD of each site of the four cross-sectional reference planes (retropalatal airway [RA], second cervical vertebral airway, oropharyngeal airway and third cervical vertebral airway) were measured. The Maximum negative pressure (Pmax) of the PA was measured at inspiration using CFD, based on a three-dimensional PA model. Intersite differences were determined using analysis of variance and the Friedman test with Bonferroni correction. The relationship between APD and Pmax was evaluated by Spearman correlation coefficients and non-linear regression analysis. RESULTS: The smallest PA site was the RA. Pmax was significantly correlated with the APD of the RA (rs  = .628, P < .001). The relationship between Pmax and the APD-RA was fitted to a curve, which showed an inversely proportional relationship of Pmax to the square of the APD-RA. Pmax substantially increased even with a slight reduction of the APD-RA. In particular, when the APD-RA was 7 mm or less, Pmax increased greatly, suggesting that PA obstruction was more likely to occur. CONCLUSIONS: The results of this study suggest that APD-RA is a useful predictor of good PA ventilation after surgery.

Primary site identification in children with obstructive sleep apnea by computational fluid dynamics analysis of the upper airway.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a respiratory disorder caused by the obstruction of the upper airway during sleep. The identification of the primary site of OSA is essential to determine treatment strategy. This study aimed to establish computational fluid dynamics (CFD) analysis for determining the clinical severity of OSA and the primary site of OSA. METHODS: Twenty children (mean age, 6 years) were divided into OSA and control groups according to their apnea-hypopnea index. Three-dimensional airways were constructed from computed tomography data. The pharyngeal airway morphology and the pressure and velocity of the upper airway were evaluated using CFD analysis. RESULTS: The maximum velocity and negative pressure of the upper airway in the OSA group were significantly correlated with the severity of OSA (rs = .741, P < .001; rs = -.653, P = .002). A velocity higher than 12 m/s indicated the primary site of OSA. In addition, we found that the primary site of OSA is not necessarily the same as the collapsible conduit site. CONCLUSIONS: CFD analysis allows both the evaluation of the disease severity of OSA and the identification of the primary site of OSA in children. The primary site of OSA is not necessarily the same as the collapsible conduit site; therefore, CFD analysis can be used to identify the appropriate intervention for treating OSA.

Relationship between lip motion detected with a compact 3D camera and swallowing dynamics during bolus flow swallowing in Japanese elderly men.

Clinical application of a swallowing function evaluation system that is minimally invasive and enables an objective evaluation is necessary. We constructed a system that can synchronise and analyse lip motion with a three-dimensional (3D) camera and swallowing dynamics with videofluoroscopy (VF) and clarified the relationship between lip movement and swallowing dynamics. A compact 3D camera was adapted to Microsoft XBox One Kinect Sensor® . We examined Kinect's accuracy and repeatability and analysed the highest measurement accuracy and repeatability of the distance between anguli oris muscles. The constructed system simultaneously measured, synchronised and analysed lip motion by Kinect and swallowing dynamics by VF. Fourteen elderly men without dysphagia were included. Barium turbid solution (5, 10, 15 and 20 mL) was used for swallowing. Measurement parameters were the 3D distance between angulus oris displacement (TDDD), swallowing quantity (SQ), oral transit time (OTT), stage transit duration (STD), pharyngeal transit time (PTT) and total swallowing duration (TSD). Statistical analyses were performed. The measurement accuracy and reproducibility were optimum within a 10° horizontal imaging angle at a 120-cm measurement distance. SQ, TDDD, OTT, STD, PTT and TSD showed significant differences, and correlation was found between TDDD and OTT. SQ affected TDDD, OTT, STD, PTT and TSD; OTT could be predicted from TDDD. Improvement in the system and analysis method was considered to enable prediction of swallowing dynamics from body surface movement of the head and neck, including realisation of measurement conditions with higher precision and reproducibility, and from lip motion.

How does distraction osteogenesis maxillary expansion (DOME) reduce severity of obstructive sleep apnea?

OBJECTIVE: Distraction osteogenesis maxillary expansion (DOME) is a reliable method to expand the nasal floor and hard palatal vault in adults with obstructive sleep apnea (OSA). DOME results in a reduction in the apnea-hypopnea index (AHI) and subjective report of improved nasal breathing. Using rhinomanometry augmented computational fluid dynamic (CFD) modeling, we propose a mechanism of how DOME reduces upper airway pharyngeal collapse in adults with OSA. MATERIAL AND METHOD: A retrospective cohort with 20 subjects and mean age of 29.6 ± 8 years who completed DOME at Stanford University from September 2014 to April 2016. Subjects were included if polysomnography, airway morphology, and rhinomanometry were available for use. From the CBCT data, 3D nasal and pharyngeal airway model were generated. Numeric CFD simulation of the airway models were analyzed under the following conditions: (1) the volume of air was flowing at a velocity of 300 cm3/s, (2) the wall surface was not slippery, and (3) the simulations were repeated 1000 times to calculate mean values. Statistical analyses using SPSS v24 software included paired t tests, nonparametric Wilcoxon rank test, Friedman test with Bonferroni correction, and Spearman's correlation coefficients (p < 0.05). RESULTS: Mean AHI improved from 17.8 ± 17.6 to 7.8 ± 7.1 events per hour (p < 0.001). Mean lowest oxygen saturation improved from 88.2 ± 7.2 to 90.9 ± 4.2% (p < 0.05). Mean airflow velocity within the nasal airway decreased from 15.6 ± 7.3 to 7.4 ± 2.1 m/s (p < 0.001) after DOME. Mean negative pressure of the nasal airway, retropalatal airway, oropharyngeal airway, and hypopharyngeal airway is reduced from - 158.4 ± 115.3 to - 48.6 ± 28.7 Pa, from - 174.8 ± 119.9 to - 52.5 ± 31.3 Pa, from - 177.0 ± 118.4 to - 54.9 ± 31.8 Pa and from - 177.9 ± 117.9 to - 56.9 ± 32.1 Pa (p < 0.001), respectively. AHI positively correlated with nasal flow velocity (p < 0.05) and negatively correlated with pharyngeal airway pressure (p < 0.05). ODI was positively correlated with nasal velocity (p < 0.05) and negatively correlated with nasal airway pressure (p < 0.05), retropalatal airway pressure (p < 0.001), oropharyngeal airway pressure (p < 0.001), and hypopharyngeal airway pressure (p < 0.05). CONCLUSION: Anatomic expansion of the nasal floor with widening of the hard palatal vault from DOME is associated with reduction of nasal airflow velocity and downstream reduction of negative pressure in the pharyngeal airway. This dynamic interaction correlates with a reduction in the apnea-hypopnea index (AHI) and Oxygen Desaturation Index (ODI).

piggyBac Transposon-Based Immortalization of Human Deciduous Tooth Dental Pulp Cells with Multipotency and Non-Tumorigenic Potential.

We aimed to immortalize primarily isolated human deciduous tooth-derived dental pulp cells (HDDPCs) by transfection with piggyBac (PB)-based transposon vectors carrying E7 from human papilloma virus 16 or complementary DNA (cDNA) encoding human telomerase reverse transcriptase (hTERT). HDDPCs were co-transfected with pTrans (conferring PB transposase expression) + pT-pac (conferring puromycin acetyltransferase expression) + pT-tdTomato (conferring tdTomato cDNA expression) and pT-E7 (conferring E7 expression) or pTrans + pT-pac + pT-EGFP (conferring enhanced green fluorescent protein cDNA expression) + pT-hTERT (conferring hTERT expression). After six days, these cells were selected in medium containing 5 µg/mL puromycin for one day, and then cultured in normal medium allowing cell survival. All resultant colonies were harvested and propagated as a pool. Stemness and tumorigenic properties of the established cell lines ("MT_E7" for E7 and "MT_hTERT" for hTERT) with untransfected parental cells (MT) were examined. Both lines exhibited proliferation similar to that of MT, with alkaline phosphatase activity and stemness-specific factor expression. They displayed differentiation potential into multi-lineage cells with no tumorigenic property. Overall, we successfully obtained HDDPC-derived immortalized cell lines using a PB-based transfection system. The resultant and parental cells were indistinguishable. Thus, E7 and hTERT could immortalize HDDPCs without causing cancer-associated changes or altering phenotypic properties.

Upper airway in children with unilateral cleft lip and palate evaluated with computational fluid dynamics.

INTRODUCTION: Children with unilateral cleft lip and palate (UCLP) exhibit snoring and mouth breathing. They are also reported to show obstructive sleep apnea syndrome. However, their upper airway ventilation condition is not clearly understood. Therefore, this study was performed to evaluate upper airway ventilation condition in children with UCLP with the use of computational fluid dynamics. METHODS: Twenty-one children (12 boys, 9 girls; mean age 9.1 years) with UCLP and 25 children (13 boys, 12 girls; mean age 9.2 years) without UCLP who required orthodontic treatment underwent cone-beam computed tomography (CBCT). Nasal resistance and upper airway ventilation condition were evaluated with the use of computational fluid dynamics from CBCT data. The groups were compared with the use of Mann-Whitney U tests and Student t tests. RESULTS: Nasal resistance of the UCLP group (0.97 Pa/cm3/s) was significantly higher than that of the control group (0.26 Pa/cm3/s; P < 0.001). Maximal pressure of the upper airway (335.02 Pa) was significantly higher in the UCLP group than in the control group (67.57 Pa; P < 0.001). Pharyngeal airway (from choanae to base of epiglottis) pressure in the UCLP group (140.46 Pa) was significantly higher than in the control group (15.92 Pa; P < 0.02). CONCLUSIONS: Upper airway obstruction in children with UCLP resulted from both nasal and pharyngeal airway effects.

Increased Expression of Cell Surface SSEA-1 is Closely Associated with Naïve-Like Conversion from Human Deciduous Teeth Dental Pulp Cells-Derived iPS Cells.

Stage-specific embryonic antigen 1 (SSEA-1) is an antigenic epitope (also called CD15 antigen) defined as a Lewis X carbohydrate structure and known to be expressed in murine embryonal carcinoma cells, mouse embryonic stem cells (ESCs), and murine and human germ cells, but not human ESCs/induced pluripotent stem cells (iPSCs). It is produced by α1,3-fucosyltransferase IX gene (FUT9), and F9 ECCs having a disrupted FUT9 locus by gene targeting are reported to exhibit loss of SSEA-1 expression on their cell surface. Mouse ESCs are pluripotent cells and therefore known as "naïve stem cells (NSCs)." In contrast, human ESCs/iPSCs are thought to be epiblast stem cells (EpiSCs) that are slightly more differentiated than NSCs. Recently, it has been demonstrated that treatment of EpiSCs with several reprograming-related drugs can convert EpiSCs to cells similar to NSCs, which led us to speculate that SSEA-1 may have been expressed in these NSC-like EpiSCs. Immunocytochemical staining of these cells with anti-SSEA-1 revealed increased expression of this epitope. RT-PCR analysis also confirmed increased expression of FUT9 transcripts as well as other stemness-related transcripts such as REX-1 (ZFP42). These results suggest that SSEA-1 can be an excellent marker for human NSCs.