Objective To compare the effect of discrete trial training(DTT),pivotal response treatment(PRT)and a combination of DTT and PRT on joint attention in children aged three to six years with mild to moderate autism spectrum disor-der(ASD). Methods From January,2023 to March,2024,39 children with ASD aged 36 to 72 months in Tiger Children's Rehabili-tation Center in Shanghai were randomly divided into DTT,PRT and combination groups,who received DTT,PRT and a combination of DTT and PRT,respectively,for ten weeks.They were assessed with Joint Attention As-sessment Scale for children with ASD before and after intervention. Results Two cases in DTT group and one case in PRT group dropped down,resulting in a final sample of 36 cases.The main effects of group(F=11.225,P<0.001)and time(F=416.935,P<0.001)were significant,as well as the interaction(F=10.501,P<0.001),and the combination group was the best during intervention and follow-up(P<0.05). Conclusion Both DTT and PRT may improve joint attention in children with ASD,and the combination of DTT and PRT is the best.

Objective This study aims to establish an approach to integrate autonomous maximal smile(AMS)3D facial image with digital 3D dental models to demonstrate the digital orthodontic set-up in the 3D facial context.Methods Using Geomagic Studio software,the AMS 3D facial image and pre-treatment dental model were manually and globally registered.Subsequently,the pre-treatment dental model was substituted with the predicted post-treatment dental model.The intraoral region of the AMS 3D facial image was removed,achieving a conjunctive display of the AMS 3D facial image and the post-treatment dental set-up.The distances between four groups of corresponding landmark pairs on the AMS 3D facial image and the pre-treatment dental set-up were calculated,and the accuracy of the registration operation was evaluated by paired t-test.Results The novel approach effectively facilitated the integration of AMS 3D facial images with the pre-treatment and predicted post-treatment 3D dental models.The average distances between the pairs of points were(1.19±0.55)mm and(1.55±0.59)mm for the two registrations,respectively.Notably,no statistically significant difference was observed be-tween the two measurements(P>0.05),indicating a high agreement(intraclass correlation coefficient=0.914).Conclu-sion This study established an approach to integrate AMS 3D facial images with digital 3D dental models.Through this approach,the digital orthodontic set-up design can be displayed in the context of a 3D facial image,which may help to improve the quality of outcome set-up in digital orthodontics,such as clear aligner therapy.

Objective : To investigate the achieved intrusion amount of the maxillary incisors and the influencing factors in clear aligner cases treated with extraction of premolars. Methods : This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. Thirty adult female patients who underwent extraction of the bilateral maxillary first premolars followed by clear aligner therapy were included. CBCT data before and after treatment were obtained, and three-dimensional reconstruction with registration alignment was performed. A spatial coordinate system was established, and the achieved intrusion amount was measured, followed by calculation of the intrusion efficacy. The factors related to the achieved intrusion amount were investigated through multiple linear regression analysis. Results : The overall efficacy of maxillary incisor intrusion was 54%, with the maxillary central incisors (48%) lower than the lateral incisors (59%), which was statistically significant (P<0.001). Regression analysis showed that the designed intrusion amount and the stepwise intrusion design were positively correlated with the achieved intrusion amount. The designed retroclination amount and use of class Ⅱ intermaxillary elastics were negatively correlated with the achieved intrusion amount. The initial overbite, overjet, crowding, upper central incisor inclination, amount of the first series of aligners, canine attachment type, posterior teeth attachment type and bite ramps had no significant correlation with the achieved intrusion amount. Conclusion In maxillary first premolar extraction cases treated with clear aligners, the upper central incisors have lower efficacy of intrusion movement than the lateral incisors. The achieved intrusion amount of maxillary incisors was influenced by multiple factors, which should be considered comprehensively for better vertical control in such cases.