Background parenchymal enhancement on contrast-enhanced mammography: associations with breast density and patient's characteristics.

PURPOSE: To evaluate if background parenchymal enhancement (BPE) on contrast-enhanced mammography (CEM), graded according to the 2022 CEM-dedicated Breast Imaging Reporting and Data System (BI-RADS) lexicon, is associated with breast density, menopausal status, and age. METHODS: This bicentric retrospective analysis included CEM examinations performed for the work-up of suspicious mammographic findings. Three readers independently and blindly evaluated BPE on recombined CEM images and breast density on low-energy CEM images. Inter-reader reliability was estimated using Fleiss κ. Multivariable binary logistic regression was performed, dichotomising breast density and BPE as low (a/b BI-RADS categories, minimal/mild BPE) and high (c/d BI-RADS categories, moderate/marked BPE). RESULTS: A total of 200 women (median age 56.8 years, interquartile range 50.5-65.6, 140/200 in menopause) were included. Breast density was classified as a in 27/200 patients (13.5%), as b in 110/200 (55.0%), as c in 52/200 (26.0%), and as d in 11/200 (5.5%), with moderate inter-reader reliability (κ = 0.536; 95% confidence interval [CI] 0.482-0.590). BPE was minimal in 95/200 patients (47.5%), mild in 64/200 (32.0%), moderate in 25/200 (12.5%), marked in 16/200 (8.0%), with substantial inter-reader reliability (κ = 0.634; 95% CI 0.581-0.686). At multivariable logistic regression, premenopausal status and breast density were significant positive predictors of high BPE, with adjusted odds ratios of 6.120 (95% CI 1.847-20.281, p = 0.003) and 2.416 (95% CI 1.095-5.332, p = 0.029) respectively. CONCLUSION: BPE on CEM is associated with well-established breast cancer risk factors, being higher in women with higher breast density and premenopausal status.

1,2-Redox Transpositions of Tertiary Amides.

Reactions capable of transposing the oxidation levels of adjacent carbon atoms enable rapid and fundamental alteration of a molecule's reactivity. Herein, we report the 1,2-transposition of the carbon atom oxidation level in cyclic and acyclic tertiary amides, resulting in the one-pot synthesis of 1,2- and 1,3-oxygenated tertiary amines. This oxidation level transfer was facilitated by the careful orchestration of an iridium-catalyzed reduction with the functionalization of transiently formed enamine intermediates. A novel 1,2-carbonyl transposition is described, and the breadth of this redox transposition strategy has been further explored by the development of aminoalcohol and enaminone syntheses. The diverse ß-functionalized amine products were shown to be multifaceted and valuable synthetic intermediates, accessing challenging biologically relevant motifs.

Thread lifting of the midface: A pilot study for quantitative evaluation.

Volume restoration remains the principal target to be addressed when approaching midface rejuvenation, and absorbable sutures can create a suspension system that addresses ptotic skin located primarily in the midface. The aim of this pilot study was to investigate the effectiveness in lifting sagging tissue and to determine the outcome of thread lifting procedures of the midface. Six participants were enrolled and treated with suspension threads to correct mild to moderate ptosis of the flabby tissues of the midface. Volumetric changes were calculated at t0 (pretreatment), t1(120 days) and t2 (365 days), with a mean follow-up time of 349.64 days, (range from 304 to 380.5 days). Results showed an overall average improvement of 5.59 mL at 120 days (t0-t1) after thread implantation, up to a mean value of 4.16 mL at the end of the 350 days follow up (t0-t2). A comparison was made in between and statistical analysis was performed with level of significance set at P < .05. The records shown suggest that it is possible to achieve volume restoration which lasts up to 12 months as all parameters improved significantly (P < .05) at t1 and at t2 with respect to t0. Facial tissues suspension by means of threads is therefore safe and effective, as it is possible to achieve tissue repositioning which lasts up to 12 months for the correction of mild to moderate ptosis of the midface.

Sleep bruxism in adolescents: a systematic literature review of related risk factors.

BACKGROUND: Multiple risk factors have been associated to sleep bruxism (SB). Nevertheless, there are still many unsolved issues concerning the etiology of SB that have consequences on the clinical management strategies. OBJECTIVE: Systematically review the literature to assess the relationship between risk factors and SB symptoms in adolescents (age 11-19 years). SEARCH METHODS AND SELECTION CRITERIA: PubMed, Embase, Scopus, Cochrane Oral Health Group's Trial Register and Cochrane Register of Controlled Trials, Web of Science, LILACs, and SciELO were searched to identify all peer-reviewed articles potentially relevant to the review. DATA COLLECTION AND ANALYSIS: The risk of bias was assessed according to the guidelines from the Cochrane handbook for systematic reviews of interventions, with reporting in agreement to the preferred reporting items for systematic reviews and meta-analyses guidelines. RESULTS: Four out of the 4546 initially identified articles were selected. According to the grading of recommendations assessment, development and evaluation assessment (GRADE), the magnitude of agreement was almost perfect for all checklist items. Sleep disturbances, and snoring in particular, headache, jaw muscle fatigue, and tooth wear seem to be associated to SB in adolescents from 11 to 19 years old. LIMITATIONS: Despite the large interest of the scientific community in the field of oral parafunctions, only four articles met the eligibility criteria. Furthermore only associations and not definite cause-effect relationships were highlighted in the selected articles. CONCLUSIONS: Sleep disturbances presented the strongest association with SB while very few occlusal features had a moderate association. As a common sense the investigation of sleep respiratory disorders could be of great help in the management of SB in adolescents.

Diagnostic accuracy and measurement sensitivity of digital models for orthodontic purposes: A systematic review.

INTRODUCTION: Our objective was to assess the accuracy, validity, and reliability of measurements obtained from virtual dental study models compared with those obtained from plaster models. METHODS: PubMed, PubMed Central, National Library of Medicine Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACs were searched from January 2000 to November 2014. A grading system described by the Swedish Council on Technology Assessment in Health Care and the Cochrane tool for risk of bias assessment were used to rate the methodologic quality of the articles. RESULTS: Thirty-five relevant articles were selected. The methodologic quality was high. No significant differences were observed for most of the studies in all the measured parameters, with the exception of the American Board of Orthodontics Objective Grading System. CONCLUSIONS: Digital models are as reliable as traditional plaster models, with high accuracy, reliability, and reproducibility. Landmark identification, rather than the measuring device or the software, appears to be the greatest limitation. Furthermore, with their advantages in terms of cost, time, and space required, digital models could be considered the new gold standard in current practice.

Laypeople's perceptions of frontal smile esthetics: A systematic review.

INTRODUCTION: The emphasis on dental esthetics has increased in recent years. There are, however, differences in esthetic perceptions among professional and lay groups. The aim of this comprehensive review was to update previous reviews and answer the following research question: Can lay thresholds for acceptance of smile esthetic anomalies be defined? METHODS: A systematic search in the medical literature (PubMed, PMC, NLM, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACs) was performed to identify all peer-reviewed articles reporting data regarding evaluations of laypeople's perceptions of dental esthetic factors. RESULTS: Of the 6032 analyzed articles, 66 studies were selected for the final review process. Among the selected articles investigated perceptions of diastema, 15 analyzed modifications in tooth size and shape, 8 considered incisor positions, 15 evaluated midline discrepancies, 16 investigated buccal corridors, 26 analyzed gingival display and design, 3 considered lip height, and 20 investigated miscellaneous factors. Threshold values were identified for the following features: diastema (0-2 mm), tooth size and shape of incisor position, midline discrepancy (0-3 mm), buccal corridors (5-16 mm), gingival exposure (1.5-4 mm), occlusal canting (0°-4°), and overbite (2-5 mm). Furthermore, few other smile characteristics were found to be significantly associated with perception of smile aesthetics, even though any threshold could be detected. CONCLUSIONS: On the basis of the obtained results, threshold values for the main features of smile and dental esthetics could be identified. Limitations of the present study were the heterogeneity of data which made it impossible to perform a meta-analysis, and the lack of information about sample selection and selective outcome reporting.

Periodontal health during clear aligners treatment: a systematic review.

BACKGROUND: Clear aligner treatment (CAT) has been cited as a safe and comfortable orthodontic procedure for adult patients. However, the available evidence is scarce. OBJECTIVE: To perform a systematic review of the existing literature in order to assess periodontal health during CAT. SEARCH METHODS AND SELECTION CRITERIA: Pubmed, Pubmed Central, National Library of Medicine's Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACS were searched from January 1945 to September 2014 to identify all peer-reviewed papers potentially relevant to the review. DATA COLLECTION AND ANALYSIS: After duplicate selection and extraction procedures, the risk of bias was assessed according to the Centre for Reviews and Dissemination criteria, and a 3-point grading system, as described by the Swedish Council on Technology Assessment in Health Care (SBU), was used to rate the methodological quality of the selected papers. A PICOS table was used for data extraction. RESULTS: Five relevant articles were selected from the 1247 identified articles. The level of evidence was moderate for all the studies. A significant improvement of the periodontal health indexes was revealed, in particular when CAT was compared to fixed appliances. No periodontal CAT adverse effects were observed in the selected studies. CONCLUSIONS: Periodontal health indexes were significantly improved during CAT. The results of this review should be interpreted with some caution because of the number, quality, and heterogeneity of the included studies.

Aligner biomechanics: Where we are now and where we are heading for.

Aligner orthodontics has gained significant popularity as an alternative to traditional braces because of its aesthetic appeal and comfort. The biomechanical principles that underlie aligner orthodontics play a crucial role in achieving successful outcomes. The biomechanics of aligner orthodontics revolve around controlled force application, tooth movement, and tissue response. Efficient biomechanics in aligner orthodontics involves consideration of attachment design and optimized force systems. Attachments are tooth-colored shapes bonded to teeth, aiding in torque, rotation, and extrusion movements. Optimized force systems ensure that forces are directed along the desired movement path, reducing unnecessary strain on surrounding tissues. Understanding and manipulating the biomechanics of aligner orthodontics is essential for orthodontists to achieve optimal treatment outcomes. This approach requires careful treatment planning, considering the mechanics required for each patient's specific malocclusion. As aligner orthodontics continues to evolve, advances in material science and treatment planning software contribute to refining biomechanical strategies, enhancing treatment efficiency, and expanding the scope of cases that can be successfully treated with aligners.

The paradox of MRI for breast cancer screening: high-risk and dense breasts-available evidence and current practice.

In the mid-1990s, the identification of BRCA1/2 genes for breast cancer susceptibility led to testing breast MRI accuracy in screening women at increased risk. From 2000 onwards, ten intraindividual comparative studies showed the marked superiority of MRI: the sensitivity ranged 25-58% for mammography, 33-52% for ultrasound, 48-67% for mammography plus ultrasound, and 71-100% for MRI; specificity 93-100%, 91-98%, 89-98%, and 81-98%, respectively. Based on the available evidence, in 2006-2007, the UK National Institute for Clinical Excellence and the American Cancer Society recommended MRI screening of high-risk women, followed by other international guidelines. Despite evidence-based medicine ideally requiring randomised controlled trials (RCTs) for policy changes regarding screening procedures, breast MRI for high-risk screening was adopted in many countries worldwide. In 2019, the results of the "DENSE" RCT were published in favour of breast MRI screening of women with extremely dense breasts compared to mammography alone, showing a reduction of more than 80% of the interval cancer rate in women who attended MRI screening. Even though international recommendations in favour of this practice were issued, substantial obstacles still prevent health systems from adopting breast MRI for screening women with extremely dense breasts. A paradox is evident: we adopted a screening procedure without evidence from RCTs, and now that we have this level-1 evidence for the same procedure, we fail to do so. This critical review tries to explain the differences between the two cases, as examples of the complex pathways of translating radiological research into everyday practice.Critical relevance statement The high-level evidence in favour of breast MRI screening of women with extremely dense breasts is failing to persuade policy makers to translate this into clinical practice.Key points• Breast MRI screening of high-risk women was adopted on basis of the evidence provided by test accuracy comparative studies showing an MRI performance greatly superior to that of mammography.• Breast MRI screening of women with extremely dense breasts has not been adopted although the evidence of a large reduction in interval cancer rate from a RCT.• We illustrate the differences between the two cases, as an example of the complex ways of translation of radiological research in clinical practice according to the EBM theory.

POLITAG-M-F as Heterogeneous Organocatalyst for the Waste-Minimized Synthesis of ß-Azido Carbonyl Compounds in Batch and under Flow Conditions.

We herein report a waste minimization protocol for the ß-azidation of α,ß-unsaturated carbonyl compounds using TMSN3. The selection of the appropriate catalyst (POLITAG-M-F), in combination with the reaction medium, resulted in enhanced catalytic efficiency and a low environmental footprint. The thermal and mechanical stability of the polymeric support allowed us to recover the POLITAG-M-F catalyst for up to 10 consecutive runs. The CH3CN:H2O azeotrope has a 2-fold positive effect on the process, increasing the efficiency of the protocol and minimizing waste generation. Indeed, the azeotropic mixture, used as a reaction medium and for the workup procedure, was recovered by distillation, leading to an easy and environmentally friendly procedure for product isolation in high yield and with a low E-factor. A comprehensive evaluation of the environmental profile was performed by the calculation of different green metrics (AE, RME, MRP, 1/SF) and a comparison with other literature available protocols. A flow protocol was defined to scale-up the process, and up to 65 mmol of substrates were efficiently converted with a productivity of 0.3 mmol/min.

Variations in athletic performance with occlusal splint in track and field athletes: a randomized clinical trial.

BACKGROUND: Several studies have been proposed with the aim to demonstrate correlations between the dento-mandibular apparatus and the skeletal muscle system of the human body even in regions distant from the oral cavity. However, a definite conclusion cannot be drawn. The aim of this paper is to demonstrate a possible correlation between dental occlusion and sport performances in track and field athletes. METHODS: Sixteen track and field athletes were enrolled for the study and were randomly divided in three groups: Untreated control group, Placebo group (with a lower plaque without occlusal coverage) and Treated group (with occlusal splint). Changes in sprint and jump performance were assessed on a weekly basis for 5 consecutive weeks, during which athletes had to wear oral devices, except for the first week of baseline, for at least 3 trainings lasting 2 hours per week . All participants performed the countermovement jump (CMJ), the drop jump (DJ), the 10m and 30m sprint tests, always on the same day on the week. RESULTS: No statistically significant difference resulted between Control group and Placebo group and between Control group and Treated group. However, it was possible to observe a clinical improvement of measurements obtained, especially for CMJ, 10m and 30m sprint tests. No variation neither statistical neither clinical was observed in DJ test analysis. CONCLUSIONS: Even if statistically it was not possible to demonstrate an improvement in sport performance, most of the athlete analyzed showed better results during training session with occlusal splint compared to athlete without occlusal splint, in countermovement jump, in 10m and 30m sprint tests.

Thread Lifting of the Jawline: A Pilot Study for Quantitative Evaluation.

INTRODUCTION: The facial aging process produces changes that are characteristic of the superficial and deep fat framework and skin layers. Subdermal suspension with threads enables the sagging tissues to be lifted by means of a minimally invasive, closed procedure without surgical dissection. This observational study has been carried out on the basis of standardized tridimensional photographic analysis and measurement, aimed at determining objective, repetitive, and reliable evaluation of the soft tissue suspension technique. MATERIALS AND METHODS: Eight participants were enrolled in this pilot study presenting with mild to moderate ptosis of the jawline tissues. Patient photographs were taken before (t0), immediately after threads implantation (t1), and at the following visit (t2). Each image captured before thread insertion was registered by the software and surface linear lengths in between the mentioned points were calculated. RESULTS: The result showed an overall average improvement in the "tragus-to-marionette distance" (C-A) and the "tragus-to-jowl distance" after a mean follow-up time of 8.16 months (t0-t2). All analyzed parameters improved significantly (P < 0.05) at t1 and at t2 with respect to t0. CONCLUSIONS: This pilot study suggest that facial tissue suspension by means of poli-lactic/poli-caprolactone threads is safe and effective in treating skin flaws that affect mild-to-moderate ptosis of the jawline up to 8 months.

Clear aligner orthodontic therapy of rotated mandibular round-shaped teeth: A finite element study.

OBJECTIVE: To evaluate, using the finite element method, the orthodontic rotational movement of a lower second premolar obtained with clear aligners, analyzing different staging and attachment configurations. MATERIALS AND METHODS: A CAD model including a complete lower dental arch (with element 4.5 mesially rotated 30°) and the corresponding periodontal ligaments, attachments, and aligner was designed and imported to finite element software. Starting from the CAD model, six projects were created to simulate the following therapeutic combinations for correcting element 4.5 position: (1) without attachments, (2) single attachment placed on the buccal surface of element 4.5, (3) three attachments placed on the buccal surfaces of teeth 4.4 to 4.6. For each project, both 1.2° and 3° of aligner activation were considered. RESULTS: All the analyzed configurations revealed a clockwise rotation movement of element 4.5 on the horizontal plane. Models with attachments showed a greater tooth displacement pattern than models without attachments. Simulations with attachments and 3° of aligner activation exhibited the best performance concerning tooth movement but registered high stresses in the periodontal ligaments, far from the ideal stress levels able to produce tooth rotational movement. CONCLUSIONS: The model with a single attachment and 1.2° of aligner activation was the most efficient, followed by the three attachment model with the same degree of activation. Aligner activation should not exceed 1.2° to achieve better control of movement and reasonable stress in periodontal structures.

Correction to: Morphometric analysis of dental arch form changes in class II patients treated with clear aligners.

The authors would like to correct the conflicts of interest statement for this article. Unfortunately, the original statement did not include the authors' nonfinancial conflicts of interest, including grants and personal fees. The corrected conflict of interest statement is shown below:T. ….

Morphometric analysis of dental arch form changes in class II patients treated with clear aligners.

PURPOSE: The purpose of this study was to evaluate the arch form changes in class II Caucasian patients treated with Invisalign® (Align Technology, San José, CA, USA). METHODS: A total of 27 class II patients, for whom a maximum of 4 mm arch expansion was planned, were selected. Both maxillary and mandibular digital casts were compared at three different times: pretreatment (T0), accepted set-up (T1), and retention phase (T2). Each digital model was imported into GOM Inspect© software (GOM GmbH, Braunschweig, Germany) to identify teeth crown facial axis (FA) and cusp points to create a coordinate system. In each model the origin of the coordinates was located at the contact point of central incisors and a system of Cartesian axes was constructed. Using the FA points, an average arch form was obtained for each clinical step and then the following comparisons were performed for each class group: T0-T1, T0-T2, and T1-T2. RESULTS: T1 showed wider maxillary and mandibular dental arches compared to T0 with maximum movements observed in the premolar regions (maximum movement 1.94 mm for tooth 15; P < 0.0001). In the T1-T2 comparison, a more buccal position of tooth 22, tooth 23, and tooth 24 (maximum movement 0.56 mm; P < 0.05) and a more lingual position of tooth 37 (maximum movement 0.81 mm; P < 0.01), tooth 36, and tooth 47 were observed at T1 with respect to T2. CONCLUSIONS: Although Invisalign® treatment resulted in a significant increase in arch width according to the prescription, some of the outcomes were different than those planned especially in relation to the final position of the lower molars.

Scanning electron microscopy analysis of aligner fitting on anchorage attachments.

PURPOSE: The aims of the study were (1) to evaluate the fitting of three different aligners (Invisalign [Align Technology, Santa Clara, CA, USA], CA Clear Aligner [Scheu-Dental, Iserlohn, Germany] and F22 [Sweden&Martina, Due Carrare, Italy]) on anchorage attachments using scanning electron microscopy (SEM), and (2) to analyze the influence of 2 different types of resin used to build attachments on aligner fitting. METHODS: Using STL files of a patient, six resin casts were obtained and rectangular attachments were bonded on them. Conventional bulk-fill resin was used to build upper attachments while a flowable resin was used to build the lower ones. Passive aligners were adapted on each cast and then sectioned buccolingually. Microphotographs of the obtained sections were performed using a SEM and then micrometric measurements of aligner fitting on anchorage attachments were recorded. RESULTS: Analyzing the overall fitting of upper arch aligners, Invisalign provided a significantly better fitting with respect to F22 (P = 0.009); differences were not significant when comparing Invisalign with CA Clear Aligner, and CA Clear Aligner with F22. Analyzing the overall fitting of lower arch aligners, F22 provided a significantly better fitting with respect to CA Clear Aligner (P = 0.008) and Invisalign (P = 0.011). The analysis showed a significantly better fitting on upper attachments, built using conventional bulk-fill resin (P = 0.034). CONCLUSIONS: Invisalign, CA Clear Aligner and F22 have comparable performance in terms of fitting on anchorage attachments. Conventional bulk-fill resin provides the best fitting on anchorage attachments.

Postural changes in orthodontic patients treated with clear aligners: A rasterstereographic study.

BACKGROUND: Correlation between malocclusions and body posture has been discussed in the last decades, but there is still a lack of consensus in existing literature. Rasterstereography allows tridimensional reconstruction of the spine, starting from the back surface analysis. So far studies which tested modifications of rasterstereographic parameters during orthodontic treatment, comparing with those obtained from untreated control group, are not available. Clear aligner treatment produces alteration of vertical height due to the occlusal coverage and, subsequently, a stimulation of periodontal receptors which causes an inhibition of the jaw closing muscles and, hypothetically, changes in mandibular posture. OBJECTIVES: Evaluate possible correlations between orthodontic treatment and posture. MATERIALS AND METHODS: Rasterstereographic values of 15 untreated patients and of 15 patients treated with clear aligners were compared at baseline, after 1, 3 and 6 months. Rasterstereographic parameters considered were the following: the kyphotic angle, the lordotic angle, the upper thoracic inclination, and the pelvic inclination. RESULTS: Correlations between Kyphosis Angle, Upper Toracic Inclination and Pelvic Inclination and body posture were found after 6 months of treatment with clear aligners. CONCLUSIONS: Occlusal coverage caused by aligners could influence body posture not only for upper spine sections but also lower spine sections.

Scanning electron microscopy evaluation of aligner fit on teeth.

OBJECTIVES: The fitting of aligners on anchorage teeth is a crucial factor in clear aligner orthodontics. The purpose of this experimental study was to evaluate the fitting of two aligner systems, Invisalign and CA-Clear Aligner, using scanning electron microscopy (SEM). MATERIALS AND METHODS: Passive aligners (Invisalign and CA-Clear Aligner) were adapted on resin casts obtained by stereolithography (STL) files of a patient, and then sectioned buccolingually. Upper and lower central incisors, upper and lower first premolars, and upper and lower first molars were the regions analyzed. Representative microphotographs of sections were taken with a scanning electron microscope (SEM); a total of 160 micrometric measurements were obtained and analyzed with ANOVA tests. RESULTS: Invisalign provided an overall better fit on lower incisors ( F = 11.48, P = .0095) and on lower molars ( F = 19.93, P = .0012). Considering the different regions, Invisalign provided better fit at the gingival edge of the buccal aspect on lower incisors ( F = 11.33, P = 0.0056) and at the gingival edge of the lingual aspect on upper premolars ( F =5.34, P = 0.0047). On the upper molars, Invisalign provided better fit at the gingival edge of the buccal aspect, while CA-Clear Aligner provided better fit at the buccal maximum convexity, on the buccal cusp, on the occlusal groove and at the palatal cusp. On lower molars, Invisalign showed a more accurate fit at the buccal aspect points. CONCLUSIONS: Invisalign and CA-Clear Aligner exhibited comparable fit on anchorage teeth. Invisalign provided better fit at the gingival edges of aligners, while the CA-Clear Aligner provided better fit on complex occlusal surfaces.