Tissue engineering of the temporomandibular joint : Where do we stand now?

Tissue engineering is an alternative to traditional strategies to repair and regenerate temporomandibular joints (TMJ). Nowadays, patients suffering from severe dysfunctions of the TMJ may undergo discectomy, a procedure that consists of removing the damaged disc in hopes of reducing the symptoms.However, tissue engineering presents a potential solution for patients suffering from these disorders, due to the lack of safety and effectiveness of TMJ disc implants. Since 1991, several studies have investigated the possibility of regenerating the articular disc. This literature review aims to expose the new challenges and techniques in TMJ disc tissue engineering whether it concerns cell sourcing, scaffold or bioreactors. As these challenges are overcome, the goal of future studies remains to create a functional biological replacement of the TMJ components

Tissue engineering of the temporomandibular joint : Where do we stand now?

Tissue engineering is an alternative to traditional strategies to repair and regenerate temporomandibular joints (TMJ). Nowadays, patients suffering from severe dysfunctions of the TMJ may undergo discectomy, a procedure that consists of removing the damaged disc in hopes of reducing the symptoms.However, tissue engineering presents a potential solution for patients suffering from these disorders, due to the lack of safety and effectiveness of TMJ disc implants. Since 1991, several studies have investigated the possibility of regenerating the articular disc. This literature review aims to expose the new challenges and techniques in TMJ disc tissue engineering whether it concerns cell sourcing, scaffold or bioreactors. As these challenges are overcome, the goal of future studies remains to create a functional biological replacement of the TMJ components

A Novel 3D Evaluation of the Correlation Between the Condylar Position and Angle Classification in a Lebanese Population: A Pilot Study

Résumé Introduction : L’articulation temporo-mandibulaire (ATM) est l’une des articulations les plus complexes. Sa morphologie varie selon les individus, et même entre les côtés gauche et droit. Plusieurs études ont démontré une relation significative entre certaines caractéristiques occlusales et la morphologie articulaire. La tomodensitométrie à faisceau conique (CBCT) est actuellement la modalité la plus largement adoptée pour l’examen de l’ATM. Objectif : Cette étude vise à comparer, dans une cohorte Libanaise, l’espace interarticulaire avec les différentes classes d’Angle en utilisant le CBCT. Méthodologie : Une analyse rétrospective a été menée sur des images CBCT réalisées à l’Université Saint Joseph de Beyrouth sur une période de 1 an, entre 2021 et 2022. Quatre valeurs de clairance ont été sélectionnées, représentant la distance minimale entre l’os temporal et le condyle mandibulaire qui définit l’espace interarticulaire : 0,5 mm, 1 mm, 1,5 mm et 2 mm. Pour chaque valeur choisie, nous avons recherché la présence ou non d’une surface visible. Cette surface correspond à la zone du condyle ayant une distance du condyle à l’os temporal inférieure ou égale à la valeur choisie. Résultats : Vingt-neuf patients âgés de 12 à 60 ans ont été inclus ; 12 (41 %) étaient des hommes et 17 (59 %) des femmes. Les 48 images CBCT (23 du côté droit et 25 du côté gauche) ont été réparties en trois groupes selon la classification d’Angle : classe I (n = 14), classe II (n = 29) et classe III (n = 5). Pour une distance de [0 mm ;0,5 mm ;1mm et 1,5mm] correspondent des surfaces de valeurs nulles. Pour un intervalle compris entre [1,5 – 2mm] correspond une surface de 18,8 mm2 pour les sujets de classe I, 16,6 mm2 pour les sujets de classe II, et 30,5 mm2 pour les sujets de classe III. Les résultats n’ont pas montré de corrélation statistiquement significative entre l’espace interarticulaire et les différentes classes d’Angle. Conclusion : L’évaluation tridimensionnelle de la position condylienne par CBCT a montré qu’il n’existe pas de corrélation entre les espaces interarticulaires et les différentes classes d’Angle. Mots clés : position condylienne ; classification d’Angle ; occlusion ; CBCT ; tomodensitométrie. Abstract Introduction: The temporomandibular joint (TMJ) is one of the most complex joints. Its morphology varies between individuals, and even between the left and right sides. Several studies have found a significant relation between certain occlusal features and joint morphology. Cone-beam computed tomography (CBCT) imaging is currently the most widely adopted modality for the examination of the TMJ. Objective: This study aimed to compare the joint space in a Lebanese cohort with different Angle classification using CBCT. Methodology: We retrospectively analyzed CBCT images performed at the Saint Joseph University of Beirut in Lebanon, over a period of 1 year, between 2021 and 2022. Four clearance values were selected, representing the minimum distance between the temporal bone and the mandibular condyle that defines the joint space: 0.5 mm, 1 mm, 1.5 mm, and 2 mm. For each value chosen, we looked for the presence or not of a visible surface. This surface corresponds to the area of the condyle with a distance from the condyle to the temporal bone less than or equal to the chosen value. Results: Twenty-nine patients aged between 12 and 60 years old were included; 12 (41%) were males and 17 (59%) females. We classified 48 CBCT images (23 on the right side and 25 on the left side) into three groups according to Angle’s classification: class I (n=14), class II (n=29), and class III (n=5). For a distance of [0-1.5 mm] corresponded a surface of 0 mm2. For the interval between [1.5-2 mm] corresponded a surface of 18,8 mm2 for class I subjects, 16,6 mm2 for class II, and 30,5 mm2 for class III. The results showed no statistically significant differences between the articular spaces and the different types of occlusion. Conclusion: The three-dimensional evaluation of the condylar position by CBCT showed that there are no significant differences between the joint spaces and the different types of occlusion according to Angle’s classification. Keywords: condylar position; Angle classification; occlusion; CBCT

Adverse Effects of Botulinum Toxin type-A injections in masticatory muscles on underlying bone and cartilage: a literature review

Botulinum toxin type A (BTA) injections in masticatory muscles are used to treat numerous clinical conditions. This neurotoxin causes atrophy and transient paralysis of the concerned muscles.The aim of this review is to gather and define the effects of BTA injections in masticatory muscles on the underlying cartilage and bone structures.Electronic search of Medline and Google scholar databases covering the period between January 2007 and July 2019 was carried out. Eligible articles were selected according to the inclusion/exclusion criteria. Fourteen articles were included. BTA injections may cause short term reduction of cortical bone thickness and trabeculation. On the long term, cartilage volume reduction and bone volume loss were evident on the condyle and mandibular angle, at bothinjected and non-injected mandibular bone structures. Bone mineral density remained unaffected when only one masticatory muscle was injected but was reduced when several masticatory muscles were treated with BTA. Several cellular and molecular alterations were noticed in some articles.Because of evidence of irreversible negative effects of BTA on the underlying structures, possible muscle, bone and cartilage volume reduction should be communicated to the patients prior to any intervention. Further studies are needed to fully understand the cellular mechanisms and molecular responses behind this phenomenon

Influence Of The Margin Design On The Fracture Resistance Of Implant Supported Monolithic Zirconia Crowns

The purpose of this in vitro study was to test the influence of the margin design of implant supported monolithic zirconia crowns and test if monolithic zirconia crowns with extra fine finish line thickness cemented on zirconia implant abutments can bare the maximum masticatory forces on molars and hence be used in the posterior region. Fourteen identical monolithic zirconia crowns cemented on zirconia implant abutments mounted on titanium bases and fixed on implant replicas embedded in PMMA resin were divided into two groups: group I designed with a 0.5 mm CFL (CFL) and group II with a feather-edge finish line (FEFL) of 0.3 mm. All specimens underwent static load until fracture in order to determine the break force. Break forces in N were recorded for each group. The CFL group exhibited slightly higher fracture resistance (1879.14 ± 322.28 N) compared to the feather-edge finish line group (1685.00 ± 362.18 N). However, statistical analysis revealed that the observed difference between the two groups (194.14 ± 183.24; p = 0.310) was not significant. Within the limitations of this study, both monolithic zirconia crowns with 0.5 mm chamfer and 0.3 mm feather edge margins cemented on zirconia implant abutments can be used in the posterior region as their resistance to fracture is similar and surpasses the maximum masticatory force applied on molars

Application of non-destructive testing methods for assessing fracture resistance in dental ceramics: the sound harvesting test

IntroductionEvaluating the fracture resistance of dental ceramics such as monolithic zirconia crowns is crucial for assessing their durability. Conventional destructive laboratory tests often fail to accurately evaluate the timing and failing crack formation of these brittle materials. Non-destructive testing methods, such as acoustic emission testing (AET), offers an alternative by providing valuable data on material properties without causing damage to the samples.The in vitro study aimed to evaluate the sensitivity of a sound harvesting modified acoustic emission testing by comparing the fracture resistance of posterior monolithic zirconia crowns (MZCs) measured via the modified set up with that of a conventional fracture toughness test.Material and methodsA modified acoustic emission set up, the sound harvesting test (SHT), featuring a condenser microphone, an amplifier, a custom audio chipset and a cut-off switch integrated into a universal testing machine, was compared to a conventional fracture toughness test to measure fracture loads on 50 posterior monolithic zirconia crowns divided in two groups.ResultsThe sound harvesting test recorded a mean fracture load of 1,108.99 N, significantly less than the 1,292.52 N measured with the conventional test, indicating a more sensitive detection of fractures. Statistically significant differences (p < 0.05) were observed between the two groups.ConclusionDespite its limitations, the study suggests considering sound harvesting testing as an potential alternative for fracture load testing of dental brittle materials due to its ability to identify failures at lower loads enhancing therefore a more accurate evaluation of the behavior of dental materials. However, further testing on a broader range of dental materials is warranted to improve result accuracy and applicability

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.