Background: Dental caries is one of the most common and difficult to control chronic infections in children, characterized by its early onset and rapid progression. The objective of the study was to investigate the current status of primary caries and determine the factors related to dental caries in children aged 3-5 years in Hue city in 2020. Subjects and methods: A cross-sectional descriptive study of 464 children and their direct caregivers in 4 kindergartens of Hue city from June 2020 to October 2020. Clinical examination of the children’s oral health and interview with parent/caregiver using to a set of questions to identify related factors. Results: Overall caries prevalence was 77.2%. The index of dmft was 8.82, in which the average index of tooth decay, missing, filling teeth is 8.25, 0.09, 0.48 respectively. The factors related to primary caries were significant through multivariate analysis: Age group, Number of times brushing teeth, Parents help brush teeth and Habit of eating sweets. Conclusion: The prevalence of dental caries in preschool children in Hue city is still very high. It is necessary to have appropriate dental caries prevention interventions, contributing to reducing the rate of caries as in recent decision of the Vietnamese Ministry of Health on universal dental care until 2030. Key words: primary caries, preschool children, related factors.

Background: Parotid gland tumors account for 80% of all salivary gland neoplasms, but 80% of parotid tumors are benign. In the presence of a parotid mass, a physical examination is the first diagnostic tool and, in most cases, it guides the clinician in the appropriate direction. A fine needle aspiration biopsy (FNA) has been indicated by several authors for the diagnostic work-up. Ultrasonography, computed tomography, and/ or magnetic resonance imaging are useful complementary studies for proper surgical planning. Objective: Study clinical, paraclinical features of parotid gland tumor surgery. Materials and Methods: 31 patients with parotid gland tumor who were examined at Hue University of Medicine and Pharmacy Hospital from June 2019 to June 2020 were recorded about clinical, paraclinical of tumour. Results: Parotid salivary gland tumors in men account for 54.8, the mean age of patients was 53.7±12.3. Majority of the parotid gland tumor size in ultrasound were between 2 and 4 cm (67.7%), homogenous (67.7%). Majority of the parotid gland tumor size in CT scanner encountered were between 2 and 4 cm (67.7%), homogenous (61.3%) and in the superficial lobe (96.8). Preoperative fine needle aspiration biopsy (FNA) results showed 35.5% pleomorphic adenoma. Conclusion: FNA - Fine Needle Aspiration, Ultrasound and CT scanner were very valuable for diagnosis. Key words: salivary gland neoplasms, tumors

Background: Salivary gland tumors are the most complex and diverse of any organ in the body. Surgery is the mainstay of treatment for salivary gland tumor. Assessing the results of parotid gland tumor treatment is the aim of the study. Objective: To evaluate the results of parotid gland tumor surgery. Materials and Methods: 31 patients with parotid gland tumor who were examined at Hue University of Medicine and Pharmacy Hospital from June 2019 to June 2020 were recorded about clinical, paraclinical and evaluated results at 1 week, 1 month and 3 months after surgery. Results: Histopathological study of parotid salivary gland tumors: pleomorphic adenoma (64.5%), warthin tumour (32.3%), oncocytoma (3.2%). After parotid surgery, cervicofacial branches being the most commonly affected (29%). The most common complication was numbness around the earlope (77.4%), facial paralysis (41.9%), hemorrhage (29.1%), seroma (3.2%) and salivary fistula (3.2%). Conclusion: After performing parotid surgery, facial nerve injury was temporary Key words: Parotid gland, parotidectomy, facial paralysis