Objective:In order to solve the problem that traditional theoretical examination has become more and more difficult to comprehensively and accurately evaluate the students' understanding, taking the endodontics course as the breakthrough, this study investigates the application of process evaluation method based on the "four-step" teaching method in the endodontics experimental courses. Meanwhile, the characteristics and feasibility and significance of the study are expounded.Methods:A total of 64 students were selected from two grades majoring in Stomatology in Medical School of Shenzhen University, and they were taught and assessed according to the new or old course designs. At the end of the course, comparisons of course assessment scores between the two grades were finished and the questionnaire survey was conducted to evaluate the teaching effect. SPSS 23.0 was used to perform the independent-samples t-test. Results:The analysis showed that 84.38%(27/32) of the students thought that the "four-step" teaching method helped with the learning of endodontics and significantly improved the scores of the experimental course; 90.62%(29/32) of the students thought it was helpful to stimulate self-learning skills. Compared with the students in the Class of 2018, the students in the Class of 2019 had significantly higher experimental examination scores [(87.29±4.13) vs. (84.07±1.77), P<0.01], while the scores of theoretical examination showed no significant difference between the two grades [(78.07±5.70) vs. (76.52±6.49)]. Conclusions:This teaching reform has provided the opportunities for practical operations, improved the quality of practical teaching and also stimulated the interest in independent learning of students. Moreover, it can accumulate experience for the reform of other dental experimental courses.

Objective:In order to solve the problem that traditional theoretical examination has become more and more difficult to comprehensively and accurately evaluate the students' understanding, taking the endodontics course as the breakthrough, this study investigates the application of process evaluation method based on the "four-step" teaching method in the endodontics experimental courses. Meanwhile, the characteristics and feasibility and significance of the study are expounded.Methods:A total of 64 students were selected from two grades majoring in Stomatology in Medical School of Shenzhen University, and they were taught and assessed according to the new or old course designs. At the end of the course, comparisons of course assessment scores between the two grades were finished and the questionnaire survey was conducted to evaluate the teaching effect. SPSS 23.0 was used to perform the independent-samples t-test. Results:The analysis showed that 84.38%(27/32) of the students thought that the "four-step" teaching method helped with the learning of endodontics and significantly improved the scores of the experimental course; 90.62%(29/32) of the students thought it was helpful to stimulate self-learning skills. Compared with the students in the Class of 2018, the students in the Class of 2019 had significantly higher experimental examination scores [(87.29±4.13) vs. (84.07±1.77), P<0.01], while the scores of theoretical examination showed no significant difference between the two grades [(78.07±5.70) vs. (76.52±6.49)]. Conclusions:This teaching reform has provided the opportunities for practical operations, improved the quality of practical teaching and also stimulated the interest in independent learning of students. Moreover, it can accumulate experience for the reform of other dental experimental courses.

With the development of digital technology,computer-aided design and manufacturing(CAD/CAM)combined with 3D printing technology is increasingly used in clinical and teaching applications in dentistry.In clinical dentistry,3D printing technology has been widely used in oral and maxillofacial surgery,orthodontics and implantation.Traditional oral laboratory teaching usually uses extracted teeth,resin teeth or various dental models,while 3D printing of oral models can achieve standardized,mass-produced and close-to-real clinical application,which better meets the needs of clinical pre-practice teaching.This article reviews the latest educa-tional applications of 3D printing of dental models in teaching of oral restoration,dental pulp-cavity,oral and maxillofacial surgery,and summarizes the selection of different printing processes and printing materials,aiming to apply the research strategy of 3D printing technology in pre-clinical teaching in dentistry.Finally,the article explores the trends and urgent problems that need to be solved in the development of 3D printed dental models.

Objective: This study is to repair nostril sill deformity in the cleft lip patients by reconstructing the first auxiliary muscle tension line group and to assess the therapeutic outcome. Methods: 437 cleft lip patients with nostril sill deformity underwent the surgery from January 1, 2012 to November 1, 2016.They were treated using the technique of first auxiliary muscle tension line group reconstruction to repair the deformity. Aesthetic correction evaluations were rated by the GAIS. Random digit was used to randomly select 24 patients during the follow-up for three-dimensional measurement and analysis. The preoperative and postoperative symmetry of the nostril sills were evaluated by paired t test. Results: Mucosal ischemia or wound infection occurred in 11 cases, left obvious scar on the nostril floor. Surgical incisions of the other patients were primary healing. After 6 months to 3 years follow up, GAIS questionnaires of 378 patients demonstrated that 84% patients reported great or moderate improvement of nostril sills. Three-dimensional measurements of 24 patients suggested that there were no significant differences of the nostril sill and the nasal ala between the cleft side and the normal side. Conclusions First auxiliary tension line group reconstruction, which is to restore biomechanical balance rather than merely increase muscle volume, is an effective method of nostril sill repair in the cleft lip patients. Post-operatively, the patients achieved a stable and natural nostril sill, a middle columella, as well as a narrowed nasal ala.

OBJECTIVETo classify the patients with cleft lip and palate who need orthognathic surgery and to propose the corresponding operations.

METHODSFrom January 2005 to May 2015, 121 patients with cleft lip and palate diagnosed as maxillary retrusion were treated by orthognathic surgery. Inclusion criteriar: (1) male aged over 16, female aged over 14; (2) diagnosed as non-syndromic cleft lip and palate without systemic disease and other genetic diseases; (3) without previous orthodontic and orthognathic treatment; (4) having no other craniofacial malformation. Maxillary features and repaired types were recorded.

RESULTS93 patients were included and divided into two categories depended on the dental crowding. Class I: the teeth quantity and bone quantity is coordinated, space analysis ≤ 4 mm (mild dental crowding). The forward distance of maxillary less than 6 mm was defined as Class I a (36 cases) more than 6 mm as Class I b (28 cases). Class II: the teeth quantity and bone quantity is not coordinated, space analysis > 4 mm ( moderate or severe dental crowding). After the simulation of distraction osteogenesis, the anterior crossbite was corrected defined as Class II a (23 cases), not corrected defined as Class II b (6 cases). Class I a were corrected by conventional orthognathic surgery. While Class I b were corrected by Le Fort I maxillary advancement using distraction osteogenesis. Class II a were repaired just by anterior maxillary distraction. While Class II b need to combine conventional orthognathic surgery with anterior maxillary distraction. All the patients were satisfied with the treatment effect.

CONCLUSIONSThe patients of cleft lip and palate with maxillary retrusion who need orthognathic surgery can be classified as the method mentioned above, and then choose the appropriate operations.

Adolescent ; Adult ; Cleft Lip ; complications ; Cleft Palate ; complications ; Female ; Humans ; Male ; Maxilla ; Osteogenesis, Distraction ; Osteotomy, Le Fort ; Retrognathia ; classification ; surgery