Strong and ductile titanium-oxygen-iron alloys by additive manufacturing.

Titanium alloys are advanced lightweight materials, indispensable for many critical applications1,2. The mainstay of the titanium industry is the α-ß titanium alloys, which are formulated through alloying additions that stabilize the α and ß phases3-5. Our work focuses on harnessing two of the most powerful stabilizing elements and strengtheners for α-ß titanium alloys, oxygen and iron1-5, which are readily abundant. However, the embrittling effect of oxygen6,7, described colloquially as 'the kryptonite to titanium'8, and the microsegregation of iron9 have hindered their combination for the development of strong and ductile α-ß titanium-oxygen-iron alloys. Here we integrate alloy design with additive manufacturing (AM) process design to demonstrate a series of titanium-oxygen-iron compositions that exhibit outstanding tensile properties. We explain the atomic-scale origins of these properties using various characterization techniques. The abundance of oxygen and iron and the process simplicity for net-shape or near-net-shape manufacturing by AM make these α-ß titanium-oxygen-iron alloys attractive for a diverse range of applications. Furthermore, they offer promise for industrial-scale use of off-grade sponge titanium or sponge titanium-oxygen-iron10,11, an industrial waste product at present. The economic and environmental potential to reduce the carbon footprint of the energy-intensive sponge titanium production12 is substantial.

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.

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.

Clinical significance of buccal branches of the facial nerve and their relationship with the emergence of Stensen's duct: An anatomical study on adult Taiwanese cadavers.

OBJECTIVE: This observational study on adult Taiwanese cadavers focused mainly on the intersection of buccal branches of the facial nerve with Stensen's duct, using the emergence of Stensen's duct as the reference landmark. MATERIALS AND METHODS: Thirty-five cadaveric hemifaces were included in our research. Samples with facial defects due to tumor, trauma, or surgery were all excluded. Buccal branches of the facial nerve were identified according to the Gray's Anatomy 40th edition definition. The distance was measured from the intersection to the emergence of Stensen's duct, running from the anterior border of the parotid gland. RESULTS: In the 35 hemifaces, the number of buccal branch/Stensen's duct intersections ranged from 1 to 5 (average 2.49 ± 1.15). Two-point intersections accounted for 37% (13 hemifaces) of the sample, forming the largest group. Samples of facial nerve buccal branches were divided into four types: Type 1, with two buccal branches, accounted for 37.15% (13/35); Type 2, with three buccal branches, made up 48.59% (17/35) of our samples - the biggest group (Type 2-a was the most frequent pattern among our samples, with two superior buccal branches and one inferior buccal branch, accounting for 34.31% of our samples); Type 3, with four buccal branches, accounted for only 5.7%. Three cases of double Stensen's duct were classified as Type 4, though this is supposed to be a very rare anatomical variation. With Type 2a, the most frequent pattern among our specimens, the distance from the emergence of the Stensen's duct to the emergence point of the first superior buccal branch along the anterior border of the parotid gland was 9.58 ± 5.68 mm. The distance from the emergence point to the emergence of the inferior buccal branch along the anterior border of the parotid gland was 11.03 ± 5.38 mm. The distance (D1) from Stensen's duct to the emergence of the first superiorly located buccal branch of the group Type 2-a was statistically different from the distance (D1) of the other groups (p = 0.02). No direct anastomoses or communicating fibers between upper and lower buccal branches were noted in 11 hemifaces (31%). CONCLUSION: The distribution of buccal branches was described using the emergence of Stensen's duct as a reference landmark. According to our observations, the relationship between the buccal branches and Stensen's duct was much more complicated than described in previous studies. This was the first study to investigate the complete distribution of buccal branches of the facial nerve emerging from the anterior of the parotid gland, and their relative locations and branching numbers.