Objective To evaluate the anatomic morphology of submandibular fossa. Methods Cone-beam computed tomography (CBCT) was used to analyze the anatomic morphology of submandibular fossa. Implants of various dimensions were virtually placed into the mandibular 1st and 2nd molar region. Spatial relationships among submandibular fossa , mandibular canal and implant were analyzed. Results The depth of the submandibular fossa was (1.0 ± 0.61)mm in the 1st molar region and (1.5 ± 0.61)mm in the 2nd molar region. There were no significant statistical difference in genders, sides, and tooth loss. The length of the implants was (19.7 ± 3.75)mm (d = 4 mm) and (18.6 ± 3.73)mm (d = 5 mm) in the 1st molar region and (16.2 ± 3.46) mm (d = 4 mm) and (15.2 ± 3.09)mm (d = 5 mm) in the 2nd molar region in patiens with teeth and lingual perforation; the length of the implants was (17.1 ± 3.77)mm (d = 4 mm) and (15.6 ± 3.85)mm (d = 5 mm), and (14.2 ± 4.05)mm (d = 4 mm) and (13.2 ± 4.27)mm (d = 5 mm) in patients with tooth loss, respectively. Conclusions Determination of spatial relationships among submandibular fossa , mandibular canal and implants by using CBCT has important significance in guiding dental implant surgery.

Objective To investigate the articles on liver diseases published by authors from China (excluding Hong Kong, Macao, and Taiwan regions) in Gastroenterology & Hepatology journals indexed in Science Citation Index Expanded (SCIE) in 2016-2020, to analyze the bibliographic and citation data of these articles, and to understand the contribution and impact of Chinese scholars in the field of liver disease research in recent years. Methods The data for bibliometric analysis came from the SCIE database and Journal Citation Reports (JCR). The SCIE database was searched for the journal articles published in JCR Gastroenterology & Hepatology journals in 2016-2020, with a title or abstract containing "Liver", "Hepatocellular", "Hepatitis", "Cirrhosis", or "Hepatic" and a publication type of Article. Clinical guidelines were excluded, and the records with the corresponding author's affiliation containing institutions in China (excluding Hong Kong, Macao, and Taiwan regions) were screened out. R package bibliometrix was used to calculate the frequency of citations of included articles by liver disease studies published by Chinese and global authors in the Gastroenterology & Hepatology journals in 2016-2020, and R package DescTools was used to perform the Cochran-Armitage trend test to observe the change in composition ratio. Results In the Q1 Gastroenterology & Hepatology journals in 2016-2020, liver disease studies published by Chinese authors accounted for 9.5%. In recent years, the proportion of liver disease studies published by Chinese authors in Q1 Gastroenterology & Hepatology journals continues to increase from 6.0% to 12.2% ( P < 0.001). Among the liver disease studies published by Chinese authors in Q1 Gastroenterology & Hepatology journals, 79.7% were funded by National Natural Science Foundation of China, and there was no significant change in the proportion of studies funded by National Natural Science Foundation of China and published by Chinese authors in each partition of Gastroenterology & Hepatology journals in 2016-2020. The frequency of citations of included articles by liver disease studies published by Chinese and global authors in the Gastroenterology & Hepatology journals showed that liver disease studies published by Chinese authors had a high impact in both domestic and international academic communities. Conclusion In recent years, there has been a constant increase in the number of liver disease studies published by Chinese authors in high-impact Gastroenterology & Hepatology journals indexed in SCIE, and most of these studies have been funded by National Natural Science Foundation of China. The liver disease studies published by Chinese authors in Gastroenterology & Hepatology journals have been widely recognized by domestic and international academic communities.