Dental implants are ideally placed in an orientation that allows vertical transfer of occlusal forces along their long axis. Nevertheless, optimal situations for implant placement are seldom encountered resulting in implants placement in angulated positions, which may affect their long-term success. The resonance frequency (RF) is an objective tool used to monitor stability of the implant tissue integration; however, little is known of the effect of the implant orientation in bone on the RF and its potential significance. The purpose of this research was to determine the relation between the dental implant orientation and the corresponding RF of implant. Three-dimensional (3D) modelling software was used to construct a 3D model of a pig mandible from computed tomography (CT) images. The RF of the implant was analysed using finite element (FE) modal analysis in software ANSYS (v.12). In addition, a cubical model was also developed in MIMICS to investigate the parameters affecting the relationship between RF and implant orientation in a simplified environment. The orientation angle was increased from 0 to 10 degrees in 1 degree increments and the resulting RF was analysed using correlation analysis and one-way ANOVA. Our analysis illustrated that the RF fluctuation following altering implant orientation was strongly correlated (r=0.97) with the contacting cortical to cancellous bone ratio (CCBR) at the implant interface. The most extreme RF change (from 9.81kHz to 10.07kHz) occurred when the implant was moved 0.5mm in positive z-direction, which resulted in the maximum change of CCBR from 52.9 to 54.8.
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http://dx.doi.org/10.1016/j.medengphy.2014.05.007 | DOI Listing |
J Cataract Refract Surg
January 2025
Department of Anterior Segment, Cornea and Refractive Surgery, Hospital Arruzafa, Cordoba, Spain.
Purpose: The main objective was to develop a prediction model based on machine learning to calculate the postoperative vault as well as the ideal implantable collamer lens (ICL) size, considering for the first time the implantation orientation in a Caucasian population.
Setting: Arruzafa Ophthalmological Hospital (Cordoba, Spain) and Barraquer Ophthalmology Center (Barcelona, Spain).
Design: Multicenter, randomized, retrospective study.
JACC Cardiovasc Interv
January 2025
Department of Cardiology of The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China; State Key Laboratory of Transvascular Implantation Devices, Hangzhou, China; Cardiovascular Key Laboratory of Zhejiang Province, Hangzhou, China. Electronic address:
Background: The association between coronary microcirculation and clinical outcomes in patients with intermediate stenosis remains unclear.
Objectives: The aim of this study was to assess the prognostic significance of angiography-derived index of microcirculatory resistance (angio-IMR) in patients with intermediate coronary stenosis.
Methods: This post hoc analysis included 1,658 patients from the FLAVOUR (Fractional Flow Reserve and Intravascular Ultrasound for Clinical Outcomes in Patients with Intermediate Stenosis) trial, with angio-IMR measured in each vessel exhibiting intermediate stenosis.
J Esthet Restor Dent
January 2025
Analysis of Techniques, Material and Instruments Applied to Digital Dentistry and CAD/CAM Procedures Research Group, Complutense University of Madrid, Madrid, Spain.
Objective: This case report presents the interdisciplinary retreatment of a patient with a worn full-mouth rehabilitation using defect-oriented restorations, horizontal preparations, and vertical dimension of occlusion (VDO) increase.
Clinical Considerations: A 58-year-old woman with a previous full-mouth rehabilitation presented with worn dentition, loss of VDO, and reduced posterior support. Examination revealed signs of parafunctional habits, tetracycline-stained teeth, and compromised aesthetics with exposed discolored teeth and open embrasure spaces.
Adv Mater
January 2025
Institute of Applied Bioresource Research, College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China.
Assembling natural proteins into large, strong, bone-mimetic scaffolds for repairing bone defects in large-animal load-bearing sites remain elusive. Here this challenge is tackled by assembling pure silk fibroin (SF) into 3D scaffolds with cortical-bone-like lamellae, superior strength, and biodegradability through freeze-casting. The unique lamellae promote the attachment, migration, and proliferation of tissue-regenerative cells (e.
View Article and Find Full Text PDFIntroduction: Neurotrophic factors are widely known for their protective effect on spiral ganglion neurons (SGN) and the protection of these neurons is of great importance to optimize Cochlear Implants, which directly stimulate SGN in deaf patients. Previous studies have identified Cometin - also known as Meteroin-like - to be neuroprotective and beneficial for metabolic disorders. The aim of our study was to investigate the effects of different concentrations of recombinant human Cometin (hCometin) on SGN in regard to neuroprotection and neurite outgrowth and to evaluate its neurite guidance potential using a neurite outgrowth chamber.
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