Maturation of the Female Pharyngeal Airway from Adolescence to Adulthood.

BACKGROUND: The present study aimed to investigate developmental changes in the female pharyngeal airway from adolescence to adulthood, considering variations in the anatomical structures related to the airway dimensions. METHODS: Lateral cephalograms of 214 females were analyzed and categorized into five developmental stages: early adolescence (10-13 years), middle adolescence (14-17 years), late adolescence (18-21 years), early adulthood (22-30 years), and middle adulthood (31-50 years). The focus of the analysis included the point A-Nasion-point B (ANB) angle, tongue pharyngeal airway space (TPS), epiglottis pharyngeal airway space (EPS), soft palate airway space (SPS), and the horizontal and vertical positions of the hyoid bone. RESULTS: The ANB angle exhibited significant variation across groups, being significantly larger in the early-adolescence group (4.22°) compared to the middle-adolescence, late-adolescence, and early-adulthood groups. The TPS and EPS were significantly shorter in the early-adolescence group. Negative correlations were observed between the ANB angle and the lengths of the pharyngeal airway spaces (SPS, TPS, and EPS). The horizontal and vertical positions of the hyoid bone remained stable after middle adolescence. CONCLUSION: The maturation of the ANB angle and pharyngeal airway in females seems nearly completed during middle adolescence (14-17 years). Additionally, a significant and negative correlation was identified between the ANB angle and the lengths of various pharyngeal airway spaces (SPS, TPS, and EPS). The horizontal and vertical positions of the hyoid bone showed stability after middle adolescence.

The Use of Customized Three-Dimensionally Printed Mandible Prostheses with a Pressure-Reducing Device: A Finite Element Analysis in Different Chewing Positions, Biomechanical Testing, and In Vivo Animal Study Using Lanyu Pigs.

Segmental bony defects of the mandible constitute a complete loss of the regional part of the mandible. Although several types of customized three-dimension-printed mandible prostheses (CMPs) have been developed, this technique has yet to be widely used. We used CMP with a pressure-reducing device (PRD) to investigate its clinical applicability. First, we used the finite element analysis (FEA). We designed four models of CMP (P1 to P4), and the result showed that CMP with posterior PRD deployment (P4 group) had the maximum total deformation in the protrusion and right excursion positions, and in clenching and left excursion positions, posterior screws had the minimum von Mises stress. Second, the P4 CMP-PRD was produced using LaserCUSING from titanium alloy (Ti-6Al-4V). The fracture test result revealed that the maximum static pressure that could be withstood was 189 N, and a fatigue test was conducted for 5,000,000 cycles. Third, animal study was conducted on five male 4-month-old Lanyu pigs. Four animals completed the experiment. Two animals had CMP exposure in the oral cavity, but there was no significant inflammation, and one animal had a rear wing fracture. According to a CT scan, the lingual cortex of the mandible crawled along the CMP surface, and a bony front-to-back connection was noted in one animal. A histological examination indicated that CMP was significantly less reactive than control materials (p = 0.0170). Adequate PRD deployment in CMP may solve a challenge associated with CMP, thus promoting its use in clinical practice.

Reliability and benefits of single-energy projection-based metallic artifact reduction (SEMAR) in the different orthopedic hardware for the hip.

OBJECTIVE: To evaluate the performance and reliability of the single-energy metal artifact reduction (SEMAR) algorithm in patients with different orthopedic hardware at the hips. MATERIALS AND METHODS: A total of 153 patients with hip instrumentation who had undergone CT with adaptive iterative dose reduction (AIDR) 3D and SEMAR algorithms between February 2015 and October 2019 were included retrospectively. Patients were divided into 5 groups by the hardware type. Two readers with 21 and 13 years of experience blindly reviewed all image sets and graded the extent of artifacts and imaging quality using 5-point scales. To evaluate reliability, the mean densities and image noises were measured at the urinary bladder, veins, and fat in images with artifacts and the reference images. RESULTS: No significant differences were found in the mean densities of the urinary bladder, veins, and fat between the SEMAR images with artifacts (7.57 ± 9.49, 40.29 ± 23.07, 86.78 ± 38.34) and the reference images (7.77 ± 6.2, 40.27 ± 8.66, 89.10 ± 20.70) (P = .860, .994, .392). Image noises of the urinary bladder in the SEMAR images with artifacts (14.25 ± 4.50) and the SEMAR reference images (9.69 ± 1.29) were significantly higher than those in the AIDR 3D reference images (9.11 ± 1.12) (P < .001; P < .001). All AIDR 3D images were non-diagnostic (overall quality ≤ 3) and less than a quarter of the SEMAR images were non-diagnostic (16.7-23.7%), mainly in patients with prostheses [reader 1: 91.7% (22/24); reader 2: 92.6% (25/27)]. CONCLUSION: The SEMAR algorithm significantly reduces metal artifacts in CT images, more in patients with internal fixations than in patients with prostheses, and provides reliable attenuation of soft tissues.

Skeletal Stability after Mandibular Setback via Sagittal Split Ramus Osteotomy Verse Intraoral Vertical Ramus Osteotomy: A Systematic Review.

PURPOSE: The purpose of present study was to review the literature regarding the postoperative skeletal stability in the treatment of mandibular prognathism after isolated sagittal split ramus osteotomy (SSRO) or intraoral vertical ramus osteotomy (IVRO). MATERIALS AND METHODS: The articles were selected from 1980 to 2020 in the English published databases (PubMed, Web of Science and Cochrane Library). The articles meeting the searching strategy were evaluated based on the eligibility criteria, especially at least 30 patients. RESULTS: Based on the eligibility criteria, 9 articles (5 in SSRO and 4 in IVRO) were examined. The amounts of mandibular setback (B point, Pog, and Me) were ranged from 5.53-9.07 mm in SSRO and 6.7-12.4 mm in IVRO, respectively. In 1-year follow-up, SSRO showed the relapse (anterior displacement: 0.2 to 2.26 mm) By contrast, IVRO revealed the posterior drift (posterior displacement: 0.1 to 1.2 mm). In 2-year follow-up, both of SSRO and IVRO presented the relapse with a range from 0.9 to 1.63 mm and 1 to 1.3 mm respectively. CONCLUSION: In 1-year follow-up, SSRO presented the relapse (anterior displacement) and IVRO posterior drift (posterior displacement). In 2-year follow-up, both of SSRO and IVRO showed the similar relapse distances.

Effect of Microimplant Neck Design with and without Microthread on Pullout Strength and Destruction Volume.

The microthread neck concept has been applied to dental implants. This study investigated the pullout strength and destruction volume of orthodontic microimplants with and without the microthread neck design. Fifteen microimplants (diameter: 1.5 × 10 mm) of three types (Types A and B: without microimplant neck; Type C: with microimplant neck) were tested. The insertion torque (IT), Periotest value (PTV), horizontal pullout strength (HPS), and horizontal destruction volume (HDV) of each type were measured. Kruskal-Wallis H test and Dunn's post-hoc comparison test were performed to compare the measured values of the three types of microimplants. The correlations of the measured values were used to perform the Spearman's correlation coefficient analysis. The ITs of Types B (8.8 Ncm) and C (8.9 Ncm) were significantly higher than those of Type A (5.2 Ncm). Type B yielded the lowest PTV (4.1), and no statistical differences in PTV were observed among the three types. Type A had a significantly lower HPS (158.8 Ncm) than Types B (226.9 Ncm) and C (212.8 Ncm). The three types did not exhibit any significant differences in the HDV. The results of the Spearman's correlation coefficient test revealed that HDV (ρ = 0.710) and IT (ρ = 0.813) were strongly correlated with HPS, whereas for PTV and HPS, it was not. HPS was strongly and significantly correlated with HDV. The orthodontic microimplant with a microimplant neck design did not perform better than that without a microthread in the mechanical strength test.

Investigation of the Effectiveness of Surgical Treatment on Maxillary Medication-Related Osteonecrosis of the Jaw: A Literature Review.

AIM: Medication-related osteonecrosis of the jaw (MRONJ) occurs after exposure to medication (antiresorptive or antiangiogenic agents) for bone-related complications. It is more common in the mandible than in the maxilla. The present study investigated maxillary MRONJ in elderly patients through a meta-analysis. METHODS: Keywords, including "MRONJ", "maxilla", and "surgery", were entered into databases, including Embase, PubMed/MEDLINE, Cochrane Library, and ProQuest, which were searched systematically. RESULTS: Investigating 77 studies, we found that 18 (2 case reports and 16 case series) papers conformed to the standards. The results revealed a 2.6:1 female-to-male ratio of disease occurrence. The average age of patients was 70.6 ± 5.5 years, and most patients were in the third stage (43.6%). The average time of medication usage was 50.0 ± 20.1 months. The pooled proportion of clinical efficacy of surgery was 86%. CONCLUSION: To prevent and manage MRONJ, all elderly patients should maintain proper oral hygiene and receive dental examinations regularly. Risk assessment and safety management of MRONJ should be performed by medical teams.

Changes in Pharyngeal Airway Space and Craniocervical Angle after Anterior Bimaxillary Subapical Osteotomy.

PURPOSE: This study explored the effects of genioplasty (Gep) and anterior subapical osteotomy of the maxilla and mandible (ASOMx+ASOMd) on the pharyngeal airway dimensions of patients with bimaxillary protrusion (BiP). METHOD: Thirty-two patients were divided into 2 groups. Group 1 received ASOMx+ASOMd, and group 2 received ASOMx+ASOMd+Gep. The cephalograms of the patients were collected before surgery and 2 months after surgery. Changes in the landmarks, related cephalometric angles (gonial, SN-GoGn, Y-axis, and SN-C2C4 angles), and 2 pharyngeal airway dimensions (uvulo-pharyngeal airway [UOP] and tongue-pharyngeal airway [TOP]) were analyzed. RESULTS: Before surgery, the parameters (incisor superius, incisor inferius, menton, most superior and anterior point of the hyoid bone, tip of the uvula, inferoanterior point on the second cervical vertebra, and inferoanterior point on the fourth cervical vertebra) and measured angles (SNA, SNB, ANB, gonial, SN-GoGn, Y-axis, and C4C2-SN) of both groups showed no significant differences. Following ASOMx, the patients in groups 1 and 2 exhibited a setback by 7.0 and 6.6 mm, respectively. After ASOMd, groups 1 and 2 exhibited 4.9 and 5.3 mm setbacks, respectively. No significant difference in the amount of setback was observed between groups 1 and 2. The postoperative horizontal and vertical positions of Me in group 2 were significantly forward by 6.1 mm and upward by 1.5 mm, respectively. Regarding pharyngeal airway dimensions, TOP was decreased in group 1 (1.7 mm) and group 2 (1.3 mm). In the postoperative Pearson correlation coefficient test, the horizontal and vertical positions of Me showed no significant correlation with TOP in both groups. Therefore, Gep did not prevent the reduction of TOP in group 2. CONCLUSION: After bimaxillary anterior subapical osteotomy, the TOP of patients with BiP was decreased, and this situation was unavoidable, regardless of whether Gep was performed.

Analysis of Facial Skeletal Morphology: Nasal Bone, Maxilla, and Mandible.

The growth and development of facial bones are closely related to each other. The present study investigated the differences in the nasomaxillary and mandibular morphology among different skeletal patterns. Cephalograms of 240 participants were divided into 3 groups based on the skeletal pattern (Class I, Class II, and Class III). The dimensions of nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way analysis of variance and Pearson's correlation test were used for statistical analysis. No significant differences were observed among the skeletal patterns in terms of nasal bone length, palatal length, maxillary height, or condylar length. Class II had a significantly shorter ramus, mandibular body, and entire mandibular length compared with those of Class I and Class III. Nasal ridge length exhibited a significant moderate correlated with nasal bone length (correlation coefficient: 0.433) and maxillary height (correlation coefficient: 0.535). The entire mandibular length exhibited a significant moderate correlated with ramus length (correlation coefficient: 0.485) and body length (correlation coefficient: 0.536). In conclusion, nasal and maxillary dimensions exhibited no significant difference among the 3 skeletal patterns. Mandibular body and entire mandibular lengths were significantly positively correlations with Class III skeletal patterns.

The investigation of pharyngeal airway space by cephalogram landmarks in primary school children in Taiwan.

BACKGROUND/PURPOSE: Proper breathing is essential to healthy growth and development of children. The present study aimed to investigate changes in the pharyngeal airway space in primary-school children. MATERIALS AND METHODS: Cephalometric radiographs were obtained from 93 primary-school children, who were divided into three age groups (Group I, aged 7-8 years; Group II, aged 9-10 years; and Group III, aged 11-12 years). Landmarks identified on each cephalogram included the tip of the uvula (U), hyoid bone (H), and epiglottis (E). Linear and angular measurements comprised nasopharyngeal airway (NP); PS (shortest distance from the soft palate to the pharyngeal wall); UP (distance from the tip of the uvula to the pharyngeal wall); TS (shortest distance from the posterior tongue to the pharyngeal wall); EP (distance, parallel to the X-axis, from the epiglottis to the pharyngeal wall). Statistical analysis was performed using one-way analysis of variance and Pearson correlation tests. RESULTS: Group III had the highest values for all the variables. The three groups exhibited significant differences for all pharyngeal airway variables, except for EP. The three groups had significantly different vertical U, H, and E. There were positive correlations between age and NP, PS, UP, and TS; however, no significant correlation was observed between age and EP. Age significantly correlated with the vertical U, E, and H. Correlations between age and the horizontal U, E, and H were nonsignificant. CONCLUSION: Among primary-school children from various grades, age significantly correlated with all pharyngeal airway variables, except with EP.

Antilingula as a Surgical Reference Point for Vertical Ramus Osteotomy.

PURPOSE: This study investigated the antilingula and its related landmarks, the mandibular rami, by using cone-beam computed tomography (CBCT). METHODS: CBCT images of 37 patients (74 sides of the mandibular ramus) were collected. The landmarks of antilingula (AntiL), anterior ramus (A), posterior ramus (P), superior ramus (S), and inferior ramus (I) were identified. The distances (A-AntiL, P-AntiL, S-AntiL, and I-AntiL) were statistically evaluated according to gender, side (right and left), and skeletal patterns. RESULTS: The distance from the antilingula to the anterior (A-AntiL) border of the ramus was significantly longer on the right side (14.69 mm) than on the left side (13.97 mm). Male patients had longer AntiL-P, AntiL-I, and S-I distances (18.96, 40.07, and 54.94 mm, respectively) than did female patients (16.66, 35, and 47.54 mm, respectively). Regarding skeletal patterns, the classes can be ordered as follows in terms of the measurements: class III>class II>class I. However, the differences between the classes were nonsignificant. Pearson correlation analysis revealed that gender and S-I distance were strongly correlated (r = 0.667); specifically, male patients had a longer S-I distance. A-AntiL and A-P also exhibited a strong correlation (r = 0.796). CONCLUSION: Antilingula-related distances did not differ between skeletal patterns. Among antilingula-related variables, A-AntiL could serve as a favorable measuring point during operation.

The correlation between surgical reference points: antilingula, lingula, and mandibular foramen.

The purpose of the present study was to investigate and determine the anatomical relationship between the antilingula, lingula, and mandibular foramen using cone-beam computed tomography (CBCT). METHODS: CBCT images of 90 participants (180 mandibular ramus) were collected. The locations of and distances between the antilingula, lingual, and mandibular foramen according to side (right and left) and skeletal patterns were measured and then evaluated by statistical analysis. RESULTS: Only 27 participants (15%) had bilateral distinct antilingula, lingula, and mandibular foramen. The antilingula was located anteriorly (4.28 mm and 3.59 mm) and above (1.99 mm and 8.52 mm) the lingula and mandibular foramen. The lingula was behind (0.69 mm) and above (6.53 mm) the mandibular foramen. Skeletal Class III was anterior and inferior to Class II and Class I in the antilingula, lingula, and mandibular foramen. Considering the correlations of landmarks, we found that the lingula was strongly correlated with the mandibular foramen on the X axis (r = 0.757) and Y-axis (r = 0.878). CONCLUSION: The antilingula is located anteriorly and above the lingula and mandibular foramen. The lingula is behind and above the mandibular foramen. The osteotomy line of orthognathic surgery can only be safely designed through actual measurement of the locations of the antilingula, lingula, and mandibular foramen.

Homo- and Heteropolynuclear Clusters of Phosphine Triphenolates.

The synthesis and structural characterization of a series of homo- and heteropolynuclear clusters constructed with a potentially tetradentate phosphine triphenolate ligand are presented. Treatment of tris(3,5-di-tert-butyl-2-hydroxyphenyl)phosphine (H3[O3P]) with 3 equiv of nBuLi in diethyl ether at -35 °C affords hexanuclear Li6[O3P]2(OEt2)2 (1) as colorless crystals. In situ lithiation of H3[O3P] with 3 equiv of nBuLi in THF at -35 °C followed by metathetical reactions with MnCl2 or NiCl2(DME) gives crystals of forest green pentanuclear MnLi4[O3P]2(THF)3 (2) or dark brown tetranuclear Ni2Li2[O3P]2(THF)2 (3), respectively. Alkane elimination of ZnR2 (R = Me, Et) with H3[O3P] in THF at 25 °C generates high yields of colorless crystalline trinuclear Zn3[O3P]2(THF)2 (4). The cluster structures of 1-4 were all determined by single crystal X-ray diffraction studies. These molecules represent the first examples of metal complexes supported by phosphine triphenolate derivatives. The cluster 2 contains a paramagnetic core of high spin Mn(II) (S = 5/2) as indicated by solution and solid state magnetic susceptibility measurements.

Biphenolate phosphine complexes of tin(IV).

The preparation and structural characterization of tin(IV) complexes supported by (2,2'-phenylphosphino)bis(4,6-di-tert-butylphenolate) ([OPO]2-) are described. The reaction of in-situ prepared Li2[OPO] with SnCl4 in THF at -35 degrees C produced [OPO]SnCl2(THF) as a THF adduct. Addition of SnCl4 to a THF solution of H2[OPO] in the presence of 2 equiv of NEt3 at room temperature led to the formation of the "ate" complex {[OPO]SnCl3}(HNEt3). The metathetical reactions of Li2[OPO] with R2SnCl2 (R=Me, n-Bu) in THF at -35 degrees C generated the corresponding five-coordinate dialkyl complexes [OPO]SnR2. In addition to the multinuclear NMR spectroscopic data for all new compounds, X-ray structures of [OPO]SnCl2(THF), [OPO]SnMe2, and [OPO]Sn(n-Bu)2 are presented.