Development and in vitro testing of an orthodontic miniscrew for use in the mandible.

Objective: Temporary anchorage devices (TADs) have been successfully used in the maxilla. However, in the mandible, lower success rates present a challenge in everyday clinical practice. A new TAD design will be presented that is intended to demonstrate optimization of the coupling structure as well as in the thread area for use in the mandible.

Finite Element Analysis of Fixed Orthodontic Retainers.

The efficacy of retainers is a pivotal concern in orthodontic care. This study examined the biomechanical behaviour of retainers, particularly the influence of retainer stiffness and tooth resilience on force transmission and stress distribution. To do this, a finite element model was created of the lower jaw from the left to the right canine with a retainer attached on the oral side.

Tooth mobility restriction by multistranded and CAD/CAM retainers-an in vitro study.

Objectives: Orthodontic retainers should restrict physiological tooth mobility as little as possible. While this has been investigated for multistranded retainers, there is a lack of data for novel CAD/CAM retainers. To address this, the present study compared the restriction of physiological tooth mobility in multistranded retainers and different CAD/CAM retainers.

A new CAD/CAM tooth mobility simulating model for dental in vitro investigations.

Objectives: To validate a new tooth mobility simulating in vitro model for biomechanical tests of dental appliances and restorations.

Material And Methods: Load-deflection curves for teeth in CAD/CAM models (n = 10/group, 6 teeth/model) of the anterior segment of a lower jaw with either low tooth mobility (LM) or high tooth mobility (HM) were recorded with a universal testing device and a Periotest device. All teeth were tested before and after different ageing protocols.

Comparison of six different CAD/CAM retainers vs. the stainless steel twistflex retainer: an in vitro investigation of survival rate and stability.

Purpose: To compare failure rates and maximum load capacity (F) of six different computer-aided design/computer-aided manufacturing (CAD/CAM) retainers with those of the hand-bent five-stranded stainless steel twistflex retainer.

Materials And Methods: Six groups (n = 8 per group) of commercially available CAD/CAM retainers (cobalt-chromium [CoCr], titanium grade 5 [Ti5], nickel-titanium [NiTi], zirconia [ZrO], polyetheretherketone [PEEK], and gold) and twistflex retainers were tested for long-term sufficiency and for F using a self-developed in vitro model. All retainer models underwent a simulated ageing process of about 15 years (1,200,000 chewing cycles with a force magnitude of 65 N at 45° followed by storage in water at 37 °C for 30 days).

Influence of Individual Bracket Base Design on the Shear Bond Strength of In-Office 3D Printed Brackets-An In Vitro Study.

(1) Background: Novel high-performance polymers for medical 3D printing enable in-office manufacturing of fully customized brackets. Previous studies have investigated clinically relevant parameters such as manufacturing precision, torque transmission, and fracture stability. The aim of this study is to evaluate different design options of the bracket base concerning the adhesive bond between the bracket and tooth, measured as the shear bond strength (SBS) and maximum force (F) according to DIN 13990.

Concept for the Treatment of Class III Anomalies with a Skeletally Anchored Appliance Fabricated in the CAD/CAM Process-The MIRA Appliance.

Objective: Intermaxillary elastics, anchored skeletally, represent a promising concept for treatment in adolescent patients with skeletal Class III anomalies. A challenge in existing concepts is the survival rate of the miniscrews in the mandible or the invasiveness of the bone anchors. A novel concept, the mandibular interradicular anchor (MIRA) appliance, for improving skeletal anchorage in the mandible, will be presented and discussed.

Precision of slot widths and torque transmission of in-office 3D printed brackets : An in vitro study.

Purpose: To investigate a novel in-office three-dimensionally (3D) printed polymer bracket regarding slot precision and torque transmission.

Methods: Based on a 0.022″ bracket system, stereolithography was used to manufacture brackets (N = 30) from a high-performance polymer that met Medical Device Regulation (MDR) IIa requirements.

In vivo assessment of artefacts in MRI images caused by conventional twistflex and various fixed orthodontic CAD/CAM retainers.

Purpose: To assess magnetic resonance imaging (MRI) artefacts caused by different computer-aided design/computer-aided manufacturing (CAD/CAM) retainers in comparison with conventional hand bent stainless steel twistflex retainers in vivo.

Materials And Methods: MRI scans (3 Tesla) were performed on a male volunteer with different CAD/CAM retainers (cobalt-chromium, CoCr; nickel-titanium, NiTi; grade 5 titanium, Ti5) and twistflex retainers inserted. A total of 126 landmarks inside and outside the retainer area (RA; from canine to canine) were evaluated by two blinded radiologists using an established five-point visibility scoring (1: excellent, 2: good, 3: moderate, 4: poor, 5: not visible).

Fit of anterior restorations made of 3D-printed and milled zirconia: An in-vitro study.

Objectives: To evaluate the fit of zirconia veneers made by either 3D printing or milling.

Methods: A typodont maxillary central incisor was prepared for a 0.5-mm-thick veneer and was reproduced 36 times from resin.

Diagnostic compatibility of various fixed orthodontic retainers for head/neck MRI and dental MRI.

Objectives: To evaluate the diagnostic MRI compatibility of different fixed orthodontic retainers using a high-resolution 3D-sequence optimized for artifact reduction.

Materials And Methods: Maxillary and mandibular retainers made of five different materials were scanned in vitro and in vivo at 3 T MRI using an MSVAT-SPACE sequence. In vitro, artifact volumes were determined for all maxillary and mandibular retainers (AV; AV).

Orthodontic shear bond strength and ultimate load tests of CAD/CAM produced artificial teeth.

Objectives: To investigate whether artificial CAD/CAM processed (computer-aided design/manufacturing) teeth could be a feasible option for the production of dental in vitro models for biomechanical testing.

Material And Methods: Disks (n = 10 per group) made from two different CAD/CAM-materials, one fiber-reinforced composite (FRC; Trinia, Bicon) and one polymethylmethacrylate-based resin (PMMA; Telio CAD, Ivoclar Vivadent), as well as bovine teeth (n = 10), were tested for their shear bond strength (SBS) and scored according to the adhesive remnant index (ARI). In addition, CAD/CAM-manufactured lower incisor teeth were tested for their ultimate load (F).

DIPS (Dystonia Image-based Programming of Stimulation: a prospective, randomized, double-blind crossover trial).

Introduction: Deep brain stimulation of the internal globus pallidus is an effective treatment for dystonia. However, there is a large variability in clinical outcome with up to 25% non-responders even in highly selected primary dystonia patients. In a large cohort of patients we recently demonstrated that the variable clinical outcomes of pallidal DBS for dystonia may result to a large degree by the exact location and stimulation volume within the pallidal region.

Influence of Preventive Tooth Extractions on Quality of Life in Patients with Antiresorptive Intake-A Prospective Longitudinal Study.

Background: To find out whether preventive tooth extractions in patients on antiresorptive therapy have a direct impact on the patients' overall quality of life (QoL); Methods: QoL using the five-level version of the EuroQol Group's EQ-5D instrument (EQ-5D-5L) was longitudinally assessed in N = 114 prospectively enrolled patients with indication of preventive tooth extraction over a period of 12 months. Patients were stratified as high-risk (malignant disease with bone metastasis or multiple myeloma, with monthly high-dose antiresorptive therapy delivered intravenously [bisphosphonate] or subcutaneously [denosumab]) and low-risk/osteoporosis patients (weekly low-dose antiresorptive therapy administered orally [bisphosphonate] or half-yearly subcutaneously [denosumab]). The measurement time points were 4 weeks preoperatively (T0), 2 months (T1) and 1 year postoperatively (T2), respectively.

Mechanical properties of CAD/CAM-fabricated in comparison to conventionally fabricated functional regulator 3 appliances.

Manufacturing of Fränkel's functional regulator 3 (FR3) is complicated and requires extensive knowledge from the dental technician. To determine whether FR3s produced by CAD/CAM techniques (CAD-FR3) meet similar mechanical properties like conventional FR3s (Con-FR3), for each of 10 patient cases, three CAD-FR3 designs (palatal connector cross-section 3 × 3 mm, 4 × 1 mm or 5 × 2 mm) and one Con-FR3 were subjected to cyclic loading and subsequent fracture testing in a universal testing device. Transversal load capacity (F) and stiffness were compared among the different CAD-FR3 designs and Con-FR3s using Friedman and Wilcoxon tests with a significance level of α = 0.

Expression of apoptosis repressor with caspase recruitment domain (ARC) in familial adenomatous polyposis (FAP) adenomas and its correlation with DNA mismatch repair proteins, p53, Bcl-2, COX-2 and beta-catenin.

Background: Colorectal familial adenomatous polyposis (FAP) adenomas exhibit a uniform pathogenetic basis caused by a germline mutation in the adenomatous polyposis gene (APC), but the molecular changes leading to their development are incompletely understood. However, dysregulated apoptosis is known to substantially affect the development of colonic adenomas. One of the key regulatory proteins involved in apoptosis is apoptosis repressor with caspase recruitment domain (ARC).

Evaluation of magnetic resonance imaging artifacts caused by fixed orthodontic CAD/CAM retainers-an in vitro study.

Objectives: Magnetic resonance imaging (MRI) image quality can be severely impaired by artifacts caused by fixed orthodontic retainers. In clinical practice, there is a trend towards using computer-aided design/computer-aided manufacturing (CAD/CAM) retainers. This study aimed to quantify MRI artifacts produced by these novel CAD/CAM retainers.

Accuracy of laser-melted patient-specific implants in genioplasty - A three-dimensional retrospective study.

Purpose: To assess the accuracy of laser-melted patient-specific implants (PSI) with regard to a preoperative virtual treatment plan for genioplasty based on a new analysis method without the use of landmarks.

Materials And Methods: A retrospective evaluation of a cohort of Class II and Class III patients who had undergone virtually planned orthognathic surgery (including genioplasty) was carried out. The preoperative virtual treatment plan and the postoperative outcome were fused to calculate the translational and rotational discrepancies between the 3D planning and the actual surgical outcome.

KCNJ6 variants modulate reward-related brain processes and impact executive functions in attention-deficit/hyperactivity disorder.

KCNJ6, encoding a potassium channel subunit, regulates the excitability of dopaminergic neurons and is expressed in attention-deficit/hyperactivity disorder (ADHD)-relevant brain regions. As a potential ADHD risk gene, KCNJ6, therefore, may contribute to the endophenotypic variation of the disorder. The impact of two SNPs, rs7275707 and rs6517442, both located in the transcriptional control region of KCNJ6, on reporter gene expression was explored in cultured cells.

Rationale and design of the Mineralocorticoid Receptor Antagonists in End-Stage Renal Disease Study (MiREnDa).

Background: End-stage renal disease (ESRD) patients exhibit an extraordinarily high annual mortality secondary to cardiac and vascular causes, particularly sudden cardiac death (SCD). Left ventricular (LV) hypertrophy is a frequent finding and constitutes an independent predictor of mortality risk in these patients. Mineralocorticoid receptor antagonists (MRAs) are cardioprotective in heart failure patients and effectively reduce LV mass, but are considered inappropriate in patients with severe renal impairment, given their potential to cause hyperkalaemia.

Influence of a genetic variant of the neuronal growth associated protein Stathmin 1 on cognitive and affective control processes: an event-related potential study.

Stathmin 1 (STMN1) is a neuronal growth associated protein (NGAP) that is involved in microtubule dynamics and plays an important role in neurite outgrowth and synaptic plasticity. It is highly expressed in the amygdala, but also in different areas of the neocortex including the frontal lobe. Based on previous findings regarding an impact of STMN1 on fear processing, the present study aimed at extending the evidence concerning its functional role to include the domain of executive (frontal lobe) functions.

Genetic dissection of alpha2-adrenoceptor functions in adrenergic versus nonadrenergic cells.

Alpha(2)-adrenoceptors mediate diverse functions of the sympathetic system and are targets for the treatment of cardiovascular disease, depression, pain, glaucoma, and sympathetic activation during opioid withdrawal. To determine whether alpha(2)-adrenoceptors on adrenergic neurons or alpha(2)-adrenoceptors on nonadrenergic neurons mediate the physiological and pharmacological responses of alpha(2)-agonists, we used the dopamine beta-hydroxylase (Dbh) promoter to drive expression of alpha(2A)-adrenoceptors exclusively in noradrenergic and adrenergic cells of transgenic mice. Dbh-alpha(2A) transgenic mice were crossed with double knockout mice lacking both alpha(2A)- and alpha(2C)-receptors to generate lines with selective expression of alpha(2A)-autoreceptors in adrenergic cells.

Molecular genetics of adult ADHD: converging evidence from genome-wide association and extended pedigree linkage studies.

A genome-wide association (GWA) study with pooled DNA in adult attention-deficit/hyperactivity disorder (ADHD) employing approximately 500K SNP markers identifies novel risk genes and reveals remarkable overlap with findings from recent GWA scans in substance use disorders. Comparison with results from our previously reported high-resolution linkage scan in extended pedigrees confirms several chromosomal loci, including 16q23.1-24.