The onset of adenosine monophosphate-activated protein kinase activity on orthodontic tooth movement in rats with type 2 diabetes.

Adenosine monophosphate-activated protein kinase (AMPK) plays pivotal roles in metabolic diseases including type 2 diabetes. However, the specific role of AMPK for orthodontic tooth movement in type 2 diabetes is unclear. In this study, a diabetic rat model was established through dietary manipulation and streptozocin injection. Examinations were conducted to select qualified type 2 diabetic rats. Then, an orthodontic device was applied to these rats for 0, 3, 7, or 14 days. The distance of orthodontic tooth movement and parameters of alveolar bone were analyzed by micro-computed tomography. Periodontal osteoclastic activity, inflammatory status, and AMPK activity were measured via histological analyses. Next, we repeated the establishment of diabetic rats to investigate whether change of AMPK activity was associated with orthodontic tooth movement under type 2 diabetes. The results showed that diabetic rats exhibited an exacerbated alveolar bone resorption, overactive inflammation, and decreased periodontal AMPK activity during orthodontic tooth movement. Injection of the AMPK agonist alleviated type 2 diabetes-induced periodontal inflammation and alveolar bone resorption, thus normalizing distance of orthodontic tooth movement. Our study indicates that type 2 diabetes decreases periodontal AMPK activity, leading to excessive inflammation elevating osteoclast formation and alveolar bone resorption, which could be reversed by AMPK activation.

Structured oral examination as an effective assessment tool in lab-based physiology learning sessions.

Traditional oral examination (TOE) is criticized for the shortage of objectivity, standardization, and reliability. These perceived limitations can be mitigated by the introduction of structured oral examination (SOE). There is little evidence of the implementation of SOE in physiology laboratory courses. The purpose of this study was to investigate the effect of SOE in laboratory-based learning sessions. Second-year medical students (n = 114) attended a 16-wk physiology laboratory course. They were initially assessed by TOE in the middle of the academic term. The students' perspectives on this assessment were measured by a modified three-point Likert-type scale questionnaire. Following this, faculty members prepared topics for SOE; nine topics were included from each laboratory course. The correct answers and scoring criteria were discussed among the faculty before the SOE event. One week after the last laboratory course, SOE was carried out for each student. As with the TOE process, student feedback was collected via a modified three-point Likert-type scale questionnaire. The mean laboratory homework score from the first four and last four laboratory courses was also calculated. Paper exams were also conducted after TOE and SOE. The results show that SOE is more acceptable to students than TOE. Significant differences (P < 0.05) were observed in terms of uniformity of questions asked, syllabus coverage, and anxiety levels. In addition, SOE improved students' performance in the laboratory course explored here. We contend that SOE shows promise as an effective assessment tool in laboratory-based physiology learning sessions.

The tooth movement efficiency of different orthodontic thermoplastics for clear aligners: study protocol for a randomized controlled clinical trial.

INTRODUCTION: With regard to the esthetics and comfort of orthodontic treatment, the requirement for removable clear aligners (CAs) is increasing. Unlike conventional fixed orthodontic appliances, CAs were made of thermoplastic film by thermoforming on the personalized dental models. The construction of orthodontic thermoplastic is a critical factor for orthodontic tooth movement (OTM). Polyethylene terephthalate glycol-modified (PETG) and thermoplastic polyurethane (TPU) are the most commonly orthodontic thermoplastics; however, the evidence of the differences between different orthodontic thermoplastic are limited to vitro environment and the evidence in vivo environment is not available. Therefore, this trial aims to provide reliable evidence for orthodontists' personalized treatment plans whether the two most commonly used orthodontic thermoplastics of PETG and TPU have differences in the efficiency of OTM. METHODS AND ANALYSIS: This randomized controlled clinical study will recruit 44 orthodontic patients for orthodontic treatment. All the subjects will be randomized into two groups (PETG and TPU, n = 22 for each group). In the first stage (M0 to M1), clear aligners will be made of two orthodontic thermoplastics and move the maxillary first or second premolars 2 mm. In the second stage, patients will take the standard orthodontic treatments. The primary outcome will be the efficiency of clear aligners made of different materials on the digital models. The secondary outcome will be the efficiency of clear aligners made of different materials on the cone-beam computed tomography (CBCT). The efficiency will be calculated through the superimposition of the digital models and CBCT. DISCUSSION: The results from this trial will serve as evidence for orthodontists and manufacturers and clarify whether the difference in orthodontic thermoplastics significantly impacts the efficiency of OTM. TRIAL REGISTRATION NUMBER: ChiCTR2300070980. Registered on 27 April 2023. https://www.chictr.org.cn/showproj.html?proj=186253.

Comparative Analysis of Clinical Effects of Mineral Trioxide Aggregate in the Treatment of Endodontic Diseases.

BACKGROUND: We aimed to evaluate the efficacy of mineral trioxide aggregate (MTA) in the treatment of endodontic disease. METHODS: Oversell, 384 patients with endodontic disease treated in Xuzhou Stomatological Hospital, Xuzhou, China, from June 2015 to June 2017 were selected, and randomly divided into four groups with 96 cases per group. The repair effects of MTA, zinc phosphate cement (ZPC), silver amalgam and light-curing calcium hydroxide (LCH) on the teeth and dental pulp of patients in the four groups were compared. Meanwhile, the ill symptoms of the patients were observed to confirm whether they could be alleviated. Besides, whether the repair effects were related to ages of patients, perforation diameters of diseased teeth and repair materials was discussed. RESULTS: The success rates of MTA group, ZPC group, LCH group and silver amalgam group were 90.6%, 68.7%, 70.8% and 52.1%, respectively. The success rate of MTA group was significantly higher than that of ZPC group, silver amalgam group and LCH group. When the success rates of four groups were compared, the differences were statistically significant (P=0.0072). The patient's age, repair material and perforation diameter were positively correlated with MTA repair effect (P=0.003, P=0.002, P=0.01). The patients' teeth in each group were repaired with different materials, and the reexamination was conducted 4 weeks later. Three patients in the silver amalgam group were found to have gingival swelling. CONCLUSION: The therapeutic effect of MTA was significant in the treatment of endodontic disease, and it is worthy of clinical application.

Toxic effects of four kinds of dental restorative materials on fibroblast HGF-1 and impacts on expression of Bcl-2 and Bax genes.

The aim of this study was to investigate and discuss the toxic effect of four kinds of dental restorative materials on fibroblast HGF-1 and their impacts on the expression of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) genes. One hundred and ninety-two patients (240 diseased teeth), who received dental restoration in the Department of Stomatology of Xuzhou Stomatology Hospital from March 2014 to March 2015, were selected and randomly divided into four groups; namely, silver amalgam group, glass-ionomer cement group, nichrome group and novel nano-composite resin group, with 60 teeth in each group. The diseased teeth were restored. The fibroblast HGF-1 was incubated in the water extracts from the four kinds of materials and ordinary cell culture fluid (negative control). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to measure the levels of Bcl-2 and Bax. A flow cytometer was applied to detect cell apoptosis. RT-qPCR results showed that compared with those in the negative control group, the mRNA expression levels of Bcl-2 in the cells of silver amalgam group, glass-ionomer cement group and nichrome group were decreased, while those of Bax were upregulated (P<0.05). The mRNA expression of Bcl-2 in glass-ionomer cement group was the highest among these three groups; the mRNA expression of Bax in nichrome group was the highest of all groups. The western blotting results revealed the same tendency as those of RT-qPCR. The results via the flow cytometer showed that cell apoptosis in nichrome group, silver amalgam group and glass-ionomer cement group was increased significantly (P<0.05) compared with that in the negative control group. The novel nano-composite resin has no obvious toxic effect on cells, and its clinical application effect is better than that of traditional dental restorative materials, which is worthy of application and generalization in clinical practice.