Purpose: To determine whether the use of social media is useful in improving compliance and follow-up attendance among patients wearing retainers after orthodontic treatment. Patients and methods: Sixty post-orthodontic patients (aged 16–19 years), randomized in two groups: follow-up supported by participation in WhatsApp chat group (SG), and Control Group (CG). All patients were scheduled for quarterly check-ups for monitoring of orthodontic stability by measurement of intercanine width at the beginning of the study (t 0 ) and every 4 months t 1 , t 2 , t 3 ) for 1 year of observation. Patients in the SG additionally participated in a WhatsApp chat group, where they would send, on a weekly basis, snapshots showing his/her occlusion. Every month, the orthodontist acting as the moderator awarded the best five snapshots by publishing a ranking in the chat. Results: Participants in the SG featured smaller changes from the intercanine widths at baseline (at debonding) compared to the CG patients at all times during 1 year of follow-up. Follow-up attendance was regular in both groups in the first 8 months of follow-up. After that, patient compliance decreased in the CG, with eight patients missing check-up appointments. Conclusion: Engaging adolescent patients directly through WhatsApp activity seems to increase regularity in wearing removable retainers, attendance to follow-up schedule, and yield better long-term outcome in terms of orthodontic stability and compliance.

Dental dimorphism can be used for discriminating sex in forensic contexts. Geometric morphometric analysis (GMA) allows the evaluation of the shape and size, separately, of uneven 3D objects. This study presents experiments using a novel combination of GMA and an artificial neural network (ANN) for sex classification, applied to premolars of Caucasian Italian adults (50 females and 50 males). General Procrustes superimposition (GPS) and the partial least square (PLS) method were performed, respectively, to study the shape variance between sexes and to eliminate landmark variations. The “set-aside” approach was used to assess the accuracy of the proposed neural networks. As the main findings of the pilot study, the proposed method applied to the first upper premolar correctly classified 90% of females and 73% of males of the test sample. The accuracy was 0.84 and 0.80 for the training and test samples, respectively. The sexual dimorphism resulting from GMA was low, although statistically significant. GMA combined with the ANN demonstrated better sex classification ability than previous odontometric or dental morphometric methods. Future research could overcome some limitations by considering a larger sample of subjects and other kinds of teeth and experimenting with the use of computer vision for automatic landmark positioning.

Background: many papers investigate the role of the cranial base in facial development, but the results are not in agreement. This can be due to a difference between the central and lateral parts of the cranial base. The aim of the present study is to evaluate the relationship between the central and the lateral cranial base and the facial skeleton in pre-pubertal peak subjects and at the end of growth. Material/Methods: a total sample of 52 latero-lateral cranial teleradiographs were analyzed. To test the correlation between structures, the “Partial Least Square” analysis was performed. Geometric morphometric analysis were applied and partial least square analysis was used to test correlation. Integration was studied removing the effect of allometry. Results: facial skeleton has no significant relation with central cranial base. Facial skeleton has significant relationships with the lateral portion of the cranial base. This relationship is higher in the post-peak phase of growth. Conclusion: the Integration between facial structures and cranial base is significant. The Spatial orientation and shape of the facial structures are both influenced by cranial base. This is mainly due to the lateral portion of cranial base.

New digital technologies are improving the accuracy of orthognathic surgery. One of the new approaches transfers the surgical plan into real surgery without using an occlusal splint. This pilot study aims to validate the splintless approach to orthognathic surgery on a series of cases. Five patients were enrolled. Surgeries were planned using a digital surgical simulation method thanks to three-dimensional images. The splintless surgical approach was planned for maxillary reposition. This consisted of cutting guides and three-dimensionally (3D) printed custom titanium plates. These two were created using the computer-aided design and computer-aided manufacturing (CAD-CAM) technique and were used intraoperatively to guide the osteotomy and repositioning of the bony segments without the use of the surgical splint. The difference between the planned surgery and the real final position was analyzed thanks to superimposition techniques and landmark analysis. Statistical tests were performed to detect significant differences. No difference was found in any of the landmarks. Midline landmarks differed from the planned position by 0.34 mm. Higher variability was found in the posterior landmark. These findings suggest that a splintless approach is useful in transferring the surgical plan without using an occlusal splint.