Clinical analysis on the root fracture of the maxillary first molar / 华西口腔医学杂志

OBJECTIVES@#This study aimed to investigate the common types and directions of root fractures of the maxillary first molar and the influence of root canal treatment on the prevalent sites of root fractures.@*METHODS@#A total of 274 maxillary first molars with root fractures diagnosed via cone beam computed tomography were included. The root fractures of nonendodontically and endodontically treated teeth were identified to be spontaneous and secondary root fractures, respectively. The sites, types, and directions of spontaneous and secondary root fractures were determined.@*RESULTS@#Among the spontaneous root fractures, the proportion of palatal root fractures (56.1%) was higher than those of mesial buccal root fractures (36.1%) and distal buccal root fractures (7.8%). Among the secondary root fractures, the proportion of mesial buccal root fractures (52.7%) was higher than those of palatal root fractures (36.5%) and distal buccal root fractures (10.8%). The distribution of predominant fracture sites was statistically significant (@*CONCLUSIONS@#This study provided an epidemiological basis for the clinical features of root fractures of the maxillary first molar. During the dia-gnosis and treatment of the maxillary first molar, the possibility of palatal root fractures should be considered. The occurrence of mesial buccal root fractures may be related to root canal treatment. Therefore, the risk of mesial buccal root fractures caused by iatrogenic factors should be minimized.

Incidence and characteristics of benign liver space-occupying mass in 17 721 patients with chronic hepatitis B: a color Doppler ultrasound-based case-control study / 南方医科大学学报

OBJECTIVE@#To analyze the incidence and risk factors of benign liver space-occupying mass in patients with chronic hepatitis B (CHB) and the ultrasound features that differentiate these masses from small hepatocellular carcinoma.@*METHODS@#We retrospectively analyzed the color Doppler and clinical data of 17 721 patients with CHB treated in the Hepatology Unit of Nanfang Hospital between January, 2016 and December, 2017. The data were compared with those of 21629 healthy control subjects undergoing routine physical examination in the Center of Heath Management of Nanfang Hospital during the same period.@*RESULTS@#Compared with the control subjects, the patients with CHB had significantly higher incidences of hepatic cysts (11.8% 8.7%, 0.05). Sonographically, the benign liver masses commonly showed homogeneous echo within the lesion with clear boundaries and regular shape. Hepatic hemangioma was distinctively hyperechoic in 83.32% (1579/1895) of the patients, while small hepatocellular carcinoma presented with weaker peripheral and internal blood flow signals with a lower flow velocity in the arteries and a higher flow velocity in the portal vein. Liver cirrhosis nodules mostly showed a mixture of strong and weak echoes (79.60%; 7637/9595) without blood flow signal within or around the nodule; an increased volume of the nodule accompanied by heterogeneous echoes within the nodule indicated an increased probability of malignant lesion. Hepatic cysts often displayed no echo within the lesion, but the echo could be enhanced posteriorly.@*CONCLUSIONS@#The patients with CHB are at a significantly higher risk of developing hepatic cysts, hepatic hemangiomas and hepatic cirrhosis nodules than the control population, and an older age and the male gender are associated with a higher incidence of hepatic cysts or cirrhosis. The differences in the sonographic and hemodynamic features can help to differentiate hepatic benign mass from malignant lesions, and kinetic changes in sonography can be used to monitor potential malignant transformation of the cirrhotic lesions.