Margherita Caccia

The purpose of this systematic review is to analyze the dentoalveolar changes resulting from the use of clear aligners in the treatment of transverse maxillary deficiency among growing children in the mixed dentition stage. An electronic literature search was carried out using the following databases: PubMed, Scopus, Cochrane Library, Embase, and Web of Science. The review protocol was prospectively registered in the PROSPERO database. Eligible studies included children aged 6 to 12 years in the mixed dentition period, presenting with erupted maxillary first molars and a transverse deficiency of the maxilla, and undergoing treatment with Invisalign^® First aligners. The review encompassed various study types including retrospective and prospective designs, randomized controlled trials, preliminary studies, and case series. Two independent reviewers conducted the data extraction process. The quality of evidence was assessed using the GRADE approach. Except for studies by Bruni et al., the risk of bias in selected articles was visually summarized in a traffic light plot using the robvis tool, following the ROBINS-I methodology. For the studies by Bruni et al., a separate visual representation was created using robvis with the RoB2 evaluation framework, prepared by the authors S.E.I. and C.A. In total, 14 studies were included in the final synthesis, selected from 265 records retrieved through electronic searches and an additional 36 identified via manual screening. Several parameters were considered in order to assess dentoalveolar expansion: intercanine width, intercanine transpalatal width, intercanine dentoalveolar width, first and second interdeciduous molar width, first and second interpremolar width, first and second interdeciduous molar transpalatal width, first intermolar width, first intermolar mesial, distal, and transpalatal width, molar inclination, arch depth, and arch perimeter, and intermolar dentoalveolar width. An improvement was recorded in all parameters. The studies comparing treatment with Invisalign^® First clear aligners and rapid maxillary expander highlighted that these both determined statistically significant differences compared to the natural growth group. Treatment with Invisalign^® First in mixed dentition proved to be very effective for dentoalveolar expansion of the maxillary arch, with good control of the crown angulation of the upper first molar and an increase in the palatal area similar to RME, compared to pre-treatment or to the natural growth group. It could represent an effective and comfortable alternative to the traditional rapid maxillary expander treatment. However, further high-quality studies are required to support our current observations and verifying the stability of treatment outcomes on a long-term basis.

The increasing emphasis on appearance and well-being has underscored the significance of self-care. From an aesthetic perspective, this entails addressing the early onset of wrinkles and the initial signs of aging. In response, new techniques have been developed, supplementing existing methods, to mitigate the signs of aging. Aesthetic speech therapy has emerged in recent years as a non-invasive procedure to combat facial aging. The objective of this study is to evaluate its effects on the signs of facial aging in participants subjected to an experimental exercise protocol over a three-month period, focusing on orbicularis and zygomatic muscles, using both a digital evaluation analysis and a self-assessment questionnaire. A cohort of 21 female subjects, aged between 50 and 65, was instructed to perform a series of 4 targeted exercises for 15 min daily over a span of three months. The participants underwent monthly evaluations, each involving the collection of standardized photographic documentation and a three-dimensional facial scan. These scans were subsequently overlaid and analyzed by a colorimetric assay at the conclusion of the study period. Statistical tests were carried out by two-way ANOVA. Additionally, during the final evaluation (T3), the participants completed a questionnaire assessing their satisfaction with their self-image and the non-invasive aesthetic treatment they received. The statistical analysis of the overlays of the collected three-dimensional scans revealed a significant volumetric change around the orbicularis oris muscle. The difference between green and blue pixels was statistically significant (p < 0.05), as was the difference between blue and yellow pixels (p < 0.05). This change did not achieve statistical significance around the zygomatic muscles. The analysis of the participants’ questionnaire responses indicated an increasing level of satisfaction with their self-image at the end of the study compared to T0. Personal confidence increased by 20%, and participants reported a 53% improvement in satisfaction with their appearance in photographs. The observed volumetric changes may be attributed to modifications in the facial muscles targeted by the exercise protocol undertaken by the participants. However, further studies are warranted to delve deeper into this issue, considering the intricate process of facial aging and the complex three-dimensional structure of the face with its various components.

This study aimed to investigate the remineralization processes of dental enamel via scanning electron microscopy and observe the changes induced in the microstructure by oral hygiene products. More specifically, the effectiveness of Mentadent Professional Resilience was analyzed for its ability to demineralize erosion-affected enamel surfaces. This involved the sectioning of some teeth to preserve enamel integrity, followed by dehydration and preparation for SEM analysis. SEM observations were made at various magnifications to detect differences in enamel morphology after treatment with the product. These observations provide valuable insights into the mechanisms of action of dental care products and their potential to protect enamel. The study makes a contribution to our understanding of remineralization processes and describes the importance of microscopic analysis for evaluating and developing effective dental products.

The aim of this study is to retrospectively investigate the predictability of maxillary arch expansion with Invisalign ^® First in mixed dentition. In a sample of 64 treated patients, 3D digital models from the ClinCheck^® software were compared with post-treatment digital models. Predicted maxillary expansion was related to the final outcome of expansion. At the cuspidal level, there was observed a predictability of 59.68% for deciduous canines, 63.77% for first deciduous molars, 66.99% for second deciduous molars, and 55.61% for first permanent molars. At the gingival level, there was observed a predictability of 49.87% for deciduous canines, 53.11% for first deciduous molars, 53.36% for second deciduous molars, and 45.16% for first permanent molars. The difference between the predicted and achieved expansion was statistically significant (p < 0.05). Within the present limitations, our results suggest that, with Invisalign^® First, it is possible to expand the upper arch in mixed dentition in an effective and predictable way. Clear aligners could represent a new and valid alternative for arch expansion in growing patients.

Background: The need to perform occasional or continuous MRI exams and the interference with metal orthodontic appliances might be important and take a primary role during retention since the retention period is significantly longer than orthodontic treatment. Several non-metallic materials were proposed as potential alternatives to perform fixed retainers in orthodontics, but they showed internal limits. Methods: Polyetheretherketone (PEEK) was used in the present clinical report as a fixed orthodontic retainer in the lower arch in order to perform an appliance with mechanical properties comparable to metallic ones but with a higher biocompatibility material and without the need for removal in case of an MRI exam. The retainer wire was handmade in the studio and then shaped to fit the arch. Results: PEEK showed a good capability for constructing a lingual fixed retainer compared to other aesthetic non-metallic and metallic materials. Conclusions: To the best of our knowledge, this study proposes how to easily build a retainer in PEEK and provides a clinical example of how this material can be beneficial.

This study presents a scanning electron microscopy analysis of a failed PEEK retainer in an orthodontic patient. After 15 months of use, the patient reported a gap opening between teeth 41 and 42. The PEEK retainer was removed and sent for electron microscope analysis. To investigate the failure, scanning electron microscopy was employed to assess the microstructure and composition of the retainer at various magnifications. These findings suggest that the failure of the PEEK retainer was multifaceted, implicating factors such as material defects, manufacturing flaws, inadequate design, environmental factors, and patient-related factors. In conclusion, this scanning electron microscopy analysis offers valuable insights into the failure mechanisms of PEEK retainers in orthodontic applications. Further research is necessary to explore preventive strategies and optimize the design and fabrication of PEEK retainers, minimizing the occurrence of failures in orthodontic practice.