Oral and maxillofacial CBCT(cone beam computed tomography)as a kind of oral imaging techniques,can accurately show the tooth pulp in an all-round way.Especially for showingthe morphologyof special root canals,it has incomparable advantages over two-dimensional X ray film.With the development of digital technology and artificial intelligence technology,CBCT has been widely used in stomatology.In this paper,we will systematically review the applicationprogress of CBCT combined with oral digital technology and arti-ficial intelligence technology,with a view to providing references for clinical diagnosis and treatmentand technical development of the discipline.

Oral and maxillofacial CBCT(cone beam computed tomography)as a kind of oral imaging techniques,can accurately show the tooth pulp in an all-round way.Especially for showingthe morphologyof special root canals,it has incomparable advantages over two-dimensional X ray film.With the development of digital technology and artificial intelligence technology,CBCT has been widely used in stomatology.In this paper,we will systematically review the applicationprogress of CBCT combined with oral digital technology and arti-ficial intelligence technology,with a view to providing references for clinical diagnosis and treatmentand technical development of the discipline.

With the proposal and development of new technologies, new methods, and new education theories, the research on medical education and teaching has been conducted extensively. The theories, methods, and management mode of the research on medical education and teaching are keeping pace with the times and thus promote the rapid improvement in teaching ability, medical talents, and the training level of medical humanities. However, current studies on medical education and teaching focus too much on the innovation of education theories, methods, and management and neglect the aspects such as educational ethics, student awareness, and assessment of potential benefits and risks. In addition, the lack of unified implementation and supervision standards in the whole process management of education research is also a problem that needs to be solved urgently, especially in empirical studies, which brings great challenges to the standardized implementation of education research. By performing an analogy with the clinical trial research system and summarizing education research and educational ethics, this study, for the first time, proposes a set of standardized and systematic medical education and research standards, including the paradigms of classification, staging and different stages. These standards provide a theoretical basis for implementing medical education research, improving the education compliance of target students, fully guaranteeing the benefits of target students, and avoiding the risks in education research, which provides a reference for standardized education research in other disciplines.

Objective To investigate the Carabelli's traits on permanent maxillary molars in Han Chinese college students.Methods Intraoral photos and plaster models from 803 Han Chinese college students were observed and the Carabelli's traits on permanent maxillary molars were categorized by the Arizona State University Dental Anthropology System.Chi-square tests were performed for the comparison of the differences between male and female,permanent maxillary first and second molars.Kendall's tau-b correlation analy-ses were performed for the correlation between bilateral antimeric molars.Results The frequencies of Carabelli's traits on permanent maxillary first and second molars were 37.61％and 3.99％respectively,46.73％and 6.30％in males,27.95％and 1.54％in females,which were statistically significant between permanent maxillary first and second molars(P＜0.01),male and female(P＜0.01).In the positive expression,the low-grade expression(ASUDAS 1-4)was predominant and accounted for 67.37％and 59.52％on the perma-nent maxillary first and second molars.The correlation between bilateral antimeric teeth were statistically significant on permanent max-illary first molars(tau-b=0.756,P＜0.01)and second molars(tau-b=0.477,P＜0.01).Conclusion The Carabelli's traits on perma-nent maxillary molars in Han Chinese college students mostly occur on permanent maxillary first molars with low-grade expression,and understanding this has great anthropological and clinical significance.

Objective:To analyze the influencing factors of thyroid volume in children aged 8 - 10 in Yunnan Province, and provide scientific basis for improving iodine deficiency disorders monitoring.Methods:From March to July 2020, in 129 counties (cities, districts) under the jurisdiction of Yunnan Province, each county (city, district) was divided into 5 sampling areas based on east, west, south, north, and middle. One township was selected from each area, and 40 non-boarding children aged 8 - 10 from one primary school were selected from each township (age balanced, half male and half female) as survey subjects. One random urine sample and household edible salt samples were collected for urine iodine and salt iodine testing, and physical examination and thyroid volume measurement were conducted for children. The influencing factors of thyroid volume were analyzed using Pearson correlation.Results:A total of 24 934 urine samples were collected from children, with a median urine iodine of 233.2 μg/L. A total of 24 933 household edible salt samples were collected from children, the median salt iodine was 24.17 mg/kg, and the qualified rate of iodized salt was 96.63% (24 003/24 839); A total of 24 937 children were examined of their thyroid gland, with a median thyroid volume of 2.62 ml and a goiter rate of 1.12% (280/24 937). Among them, there were 12 410 boys and 12 527 girls, with thyroid volumes of 2.61 and 2.64 ml, respectively. The thyroid volume of boys was positively correlated with age, height, weight, body mass index, body surface area, and salt iodine ( r = 0.15, 0.21, 0.26, 0.18, 0.25, 0.03, P < 0.001). The thyroid volume of girls was positively correlated with age, height, weight, body mass index, and body surface area ( r = 0.17, 0.26, 0.28, 0.17, 0.27, P < 0.001). Conclusion:Children aged 8 - 10 in Yunnan Province are at an iodine excess level; the age, weight, height, body mass index, and body surface area are influencing factors of thyroid volume.

Objective:To evaluate the clinical application value of the adaptive aperture by comparing intensity-modulated proton radiotherapy(IMPT) plans using and not using the aperture for brain tumors.Methods:A total of twenty patients treated with postoperative radiotherapy for brain tumors were enrolled in this study. IMPT plans were developed for each patient using and not using the adaptive aperture under the same optimization conditions. The target conformal index (CI) value, target homogeneity index (HI) value, and the dose to normal tissues of the two sets of plans were compared.Results:The IMPT plans designed using the adaptive aperture significantly increased the mean CI value from 0.58 to 0.66, while decreasing the mean 50% prescription dose volume from 797.70 cm 3 to 638.15 cm 3. These plans also reduced the irradiation doses to the cochlea, brainstem, optic chiasm, optic nerve, and lens ( t = 2.06, 3.02, 2.11, 2.58, 2.67, P < 0.05). Additionally, there was no significant difference in the HI value of the target volumes and the machine jumps (MU) between the two sets of plans ( P > 0.05). Conclusions:The adaptive aperture can significantly reduce the irradiation dose to normal tissues outside the target volumes, positively impacting the protection of organs at risk (OARs) around the target values. This demonstrates its great potential for clinical application.

This paper reviews the pathogenesis, assessment tools, influencing factors and interventions of diabetes patients with frailty at home and abroad. This paper also puts forward suggestions such as focusing on diabetes combined with frailty, taking frailty assessment as the routine assessment of diabetes patient, preparing frailty assessment tools for diabetes patients in China, and carrying out prospective investigation research, so as to provide a reference basis for early identification of frailty and formulation of individual interventions.

Objective:To understand the contents of edible salt iodine and urinary iodine of children and pregnant women in Yunnan Province, and to evaluate the iodine nutrition status, so as to provide a basis for scientific prevention and treatment of iodine deficiency disorders (IDD).Methods:From November to December 2020, one county (city) was selected from each prefecture (city), two townships (towns and streets) were selected from each county (city) and two villages (neighborhood committees) were selected from each township (town and street) from each of the 16 prefectures (cities) in Yunnan Province as the investigation sites. A total of 20 non-boarding children (male and female balanced) aged 8 - 10 years old were selected from each primary school in each village (neighborhood committee) to collect salt and urine samples. A total of 80 children were investigated in each county (city). A total of 20 pregnant women were selected from each township (town and street) to collect salt and urine samples. A total of 40 pregnant women were investigated in each county (city). All salt samples and urine samples were tested for iodine contents.Results:A total of 2 009 salt samples and 2 041 urine samples (1 375 for children, 666 for pregnant women) were collected from children aged 8 - 10 years old and pregnant women in 16 counties (cities) of Yunnan Province. Among them, the median salt iodine was 26.0 mg/kg, the coverage rate of iodized salt was 100.0% (2 009/2 009), the qualified rate of iodized salt was 98.7% (1 982/2 009), and the consumption rate of qualified iodized salt was 98.7% (1 982/2 009). The difference of salt iodine content in key populations in different counties (cities) was statistically significant ( H = 258.98, P < 0.01). The median urinary iodine of children aged 8 - 10 years old was 188.5 μg/L. There was statistically significant difference in urinary iodine content among children of different ages ( H = 29.45, P < 0.01), but there was no statistically significant difference in urinary iodine content among children of different genders ( H = 1.43, P > 0.05). In addition, the median urinary iodine of pregnant women was 141.9 μg/L, 52.1% (347/666) was < 150 μg/L. There was statistically significant difference in urinary iodine content of pregnant women in different counties (cities, H = 88.32, P < 0.01). Conclusions:The qualified rate of iodized salt, the coverage rate of iodized salt and the consumption rate of qualified iodized salt in key populations of Yunnan Province are more than 90%, and the iodized salt supply is good. Iodine nutrition of children aged 8 - 10 years old is at an appropriate level (100 - 199 μg/L); iodine nutrition of pregnant women is in an state of iodine deficiency ( < 150 μg/L). It is suggested to strengthen IDD monitoring and health education among key populations, improve residents' awareness of disease prevention, and make scientific iodine supplementation.

Minimally invasive endodontics (MIE) can preserve dental tissue to a greater extent and improve the success rate of endodontics and has thus attracted increasing attention. 3D printing is a technology that is based on a digital model and uses powdered metal, plastic and other materials to construct objects by printing layer by layer. This article reviews the application of 3D printing technology in minimally invasive endodontics to provide a reference for the application of 3D printing technology in clinical minimally invasive endodontics in the future. In recent years, 3D printing technology has been widely used in various professional fields of stomatology, such as maxillofacial surgery, prosthodontics, and orthodontics. Using cone beam computed tomography (CBCT) and oral scanners to obtain accurate data on the internal and external structures of teeth combined with 3D printing to construct a tooth diagnostic model and pulp opening guide plate, we can accurately locate the position of the root canal and provide a new method for minimally invasive endodontics. At present, 3D printing technology is mainly used to guide the pulp opening pathway, assist in the minimally invasive treatment of malformed teeth and calcified root canals, and assist with apical surgery in the field of minimally invasive endodontics. However, its accuracy and clinical prognosis still need to be verified with a large number of clinical cases.

Objective:To accurately grasp the current status of water iodine distribution in environmental of Yunnan Province, and provide a basis for scientific iodine supplementation.Methods:In 2017, according to the "National Drinking Water Iodine Content Survey Program", a survey of water iodine content was conducted in townships. In 2018, a search survey was carried out for administrative villages with water samples of iodine content > 40 μg/L in drinking water found in previous surveys. In centralized water supply villages, 2 samples of end water were collected. In decentralized or partially decentralized water supply villages, each village was divided into 5 parts: east, south, west, north and center. In villages with more than 50 water sources, 10% of the water sources were selected from each part; villages with less than 50 water sources, one water source was selected from each part; villages with less than 5 water sources, all the water sources were selected to determine the water iodine content. At the same time, the mode of water supply and demographic data were investigated.Results:At the township level water iodine survey, a total of 24 589 water samples were collected from 1 389 townships in 129 counties of 16 prefectures (cities). The median water iodine content of township was 1.3 μg/L, ranging 0.0 - 9.3 μg/L. The population covered by the survey accounted for 53.94% (25 013 804/46 371 207) of the total population of the province. According to the survey results of high iodine villages, 93 administrative villages in 68 townships of 37 counties in 12 prefectures (cities) were surveyed, covering 40 940 households and 208 880 people. A total of 761 samples of drinking water were tested, and the median water iodine content of administrative villages was 1.3 μg/L (ranging 0.0 - 196.8 μg/L). There were 2 administrative villages with iodine higher than 100 μg/L, which were Xiaobona Administrative Village (145.8 μg/L) in Liuchang Township, Xiangyun County, and Dasongshu Administrative Village (196.8 μg/L) in Yangchang Township, Xuanwei City.Conclusions:The iodine content of water in Yunnan Province is generally low, which belongs to the area of environmental iodine deficiency. For the high iodine villages, further investigation should be carried out to clarify the prevention and control measures.