Biomechanical characterization of a fibrinogen-blood hydrogel for human dental pulp regeneration.

In dental practice, Regenerative Endodontic Treatment (RET) is applied as an alternative to classical endodontic treatments of immature necrotic teeth. This procedure, also known as dental pulp revitalization, relies on the formation of a blood clot inside the root canal leading to the formation of a reparative vascularized tissue similar to dental pulp, which would provide vitality to the affected tooth. Despite the benefit of this technique, it lacks reproducibility due to the fast degradation and poor mechanical properties of blood clots.

In vitro, ex vivo, and in vivo models for dental pulp regeneration.

Based on the concept of tissue engineering (Cells-Scaffold-Bioactive molecules), regenerative endodontics appeared as a new notion for dental endodontic treatment. Its approaches aim to preserve dental pulp vitality (pulp capping) or to regenerate a vascularized pulp-like tissue inside necrotic root canals by cell homing. To improve the methods of tissue engineering for pulp regeneration, numerous studies using in vitro, ex vivo, and in vivo models have been performed.

Concordance study between regular face-to-face dental diagnosis and dental telediagnosis using fluorescence.

Background: Teledentistry consultations are an effective way to increase access to care. Whether it be for a screening, referral or even an adapted treatment plan for a certain number of patients whose access to care is complicated, demonstrating the reliability of remote consultations is essential in allowing the technique to become generalised.

Aim: This study aimed to determine if teledentistry consultations using fluorescence are of the same quality as regular consultations in the diagnosis of caries.

Performance of Fluorescence-based Systems in Early Caries Detection: A Public Health Issue.

Aim: Modern clinical caries management involves early stage caries diagnosis and should fit with dental health policy. The objective of this study was to achieve early caries detection in enamel and dentine with a laser-based system (DIAGNOdent™ pen) first and secondary with a new fluorescence intra-oral camera (Soprolife®). A visual inspection with a loupe was used as control.

A Five-year Comparative Study of Perceived Stress Among Dental Students at Two European Faculties.

Aim: To compare the levels, causes and the impact of stress from cohort of fifthyear dental students in the Faculties of Dental Medicine in Plovdiv, Bulgaria and Montpellier, France.

Materials And Methods: The questionnaire we used comprised the modified version of the 56-item Dental Environment Stress (DES) questionnaire. It was completed by fifth-year undergraduate dental students in both faculties in 2011 and 2016, totaling 335 dental students.

Multiphoton Microscopy for Caries Detection with ICDAS Classification.

Dentin carious lesion is a dynamic process that involves demineralization and collagen denaturation. Collagen type I is the major protein in dentin and it has been investigated based on its optical properties. Multiphoton microscopy (MPM) is a nonlinear imaging technique that reveals the caries process using the collagen two-photon excitation fluorescence (2PEF) and its second-harmonic generation (SHG).

Confocal Raman mapping of collagen cross-link and crystallinity of human dentin-enamel junction.

The separation zone between enamel and dentin [dentin-enamel junction (DEJ)] with different properties in biomechanical composition has an important role in preventing crack propagation from enamel to dentin. The understanding of the chemical structure (inorganic and organic components), physical properties, and chemical composition of the human DEJ could benefit biomimetic materials in dentistry. Spatial distribution of calcium phosphate crystallinity and the collagen crosslinks near DEJ were studied using confocal Raman microscopy and calculated by different methods.

Strategies For Immobilization Of Bioactive Organic Molecules On Titanium Implant Surfaces - A Review.

Numerous approaches have been used to improve the tissue-implant interface of titanium (Ti) and titanium alloy (Ti6Al4V). They all aim at increasing cell migration and attachment to the metal, preventing unspecific protein adsorption and improving post-implantation healing process. Promising methods for titanium and titanium alloy surface modification are based on the immobilization of biologically active organic molecules.

Root canal hydrophobization by dentinal silanization: improvement of silicon-based endodontic treatment tightness.

A new strategy to improve silicon-based endodontic treatment tightness by dentine hydrophobization is presented in this work: root dentine was silanized to obtain a hydrophobic dentine-sealer interface that limits fluid penetration. This strategy was based on the grafting of aliphatic carbon chains on the dentine through a silanization with the silane end groups [octadecyltrichlorosilane (OTS) and octadecyltriethoxysilane]. Dentine surface was previously pretreated, applying ethylenediaminetetraacetic acid and sodium hypochlorite, to expose hydroxyl groups of collagen for the silane grafting.

Assessment of leakage at the implant-abutment connection using a new gas flow method.

Purpose: The aim of this study was to evaluate, with a new gas flow technique, leakage at the implant/abutment junction in systems with four different connections.

Materials And Methods: Five Branemark System, five One Morse, five Intra-lock System, and five Ankylos Plus implants and abutments were used. A hole was drilled in the apex of each implant to allow gas to flow through the connection from negative to atmospheric pressure.

SVSVGMKPSPRP: a broad range adhesion peptide.

Background: A combinatorial phage display approach was previously used to evolve a 12-mer peptide (SVSVGMKPSPRP) with the highest affinity for different semiconductor surfaces. The discovery of the multiple occurrences of the SVSVGMKPSPRP sequence in an all-against-all basic local alignment search tool search of PepBank sequences was unexpected, and a Google search using the peptide sequence recovered 58 results concerning 12 patents and 16 scientific publications. The number of patent and articles indicates that the peptide is perhaps a broad range adhesion peptide.

Perceived sources of stress in fifth year dental students--a comparative study.

Introduction: The term "stress" refers to the effect of certain external factors (physical or mental) on the individual's physical and psychological health. Stress is very high in dental medicine. It may well be generated by the process of training in dentistry.

Functional mapping of human sound and carious enamel and dentin with Raman spectroscopy.

The goals of this trial were, first, to produce a Raman mapping of decay and sound dentin samples, through accurate analysis of the Raman band spectra variations of mineral and organic components. The second goal was to confirm the correlation between the Raman signal and the signal of a fluorescent camera, by assaying the concentration of pentosidine and natural collagen fluorescent crosslink using reverse phase high-pressure liquid chromatography. The first correlation assumed a possible relationship between the signal observed with the camera and Raman spectroscopy.

Molecular structural analysis of carious lesions using micro-Raman spectroscopy.

In clinical situations carious dentine tissues can be discriminated by most caries fluorescence detection tools, including a new fluorescence intra-oral camera. The objectives of this study were: (i) to analyze the Raman spectra of sound, carious, and demineralized dentine, (ii) to compare this spectral analysis with the fluorescence variation observed when using a fluorescence camera, and (iii) to evaluate the involvement of the Maillard reaction in the fluorescence variations. The first positive hypothesis tested was that the fluorescence of carious dentine obtained using a fluorescence camera and the Raman spectra variation were closely related.

[Dental pulp stem cells: characteristics, cryopreservation and therapeutic potentialities].

Stem cells discovery and their potential have led to the emergence of new forms of therapy with the development of bio-engineering cell and tissue methods underlying future medicine. The availability of stem cells and their preservation thus become an issue for everyone's health. Among the different sources of stem cells, those in the dental pulp have the advantage of being pluripotent, they can be cryopreserved and stored for long periods without losing their multiplication and differentiation capacities and finally they are easily accessible.

In vitro investigation of fluorescence of carious dentin observed with a Soprolife® camera.

Objectives: Our aim was to determine the origin of the red fluorescence of carious dentine observed with the Soprolife® camera.

Methods: We conducted in vitro studies to evaluate the origin of the red fluorescence using acids and matrix metalloproteinase (MMP) to mimic caries and methylglycoxal (MGO) to evaluate the effect of glycation reactions on the red fluorescence. In every step of these models, we detected the changes of dentin photonic response with Soprolife® in daylight mode and in treatment mode.

Multiphoton imaging of the dentine-enamel junction.

Multiphoton microscopy has been used to reveal structural details of dentine and enamel at the dentin-enamel junction (DEJ) based on their 2-photon excited fluorescence (2PEF) emission and second harmonic generation (SHG). In dentine tubule 2PEF intensity varies due to protein content variation. Intertubular dentin produces both SHG and 2PEF signals.

Development of a new quantitative gas permeability method for dental implant-abutment connection tightness assessment.

Background: Most dental implant systems are presently made of two pieces: the implant itself and the abutment. The connection tightness between those two pieces is a key point to prevent bacterial proliferation, tissue inflammation and bone loss. The leak has been previously estimated by microbial, color tracer and endotoxin percolation.

Modeling colorant leakage techniques: application to endodontics.

Objectives: Our aim was to improve the comprehension of in vitro tracer leakage studies and to determine in which conditions such studies can be reliable. We aimed to develop different theoretical models to describe either an initially dry or a wet interface (slit) between sealer and dentin.

Methodology: Equations based on physical laws were derived to model theoretically in vitro tracer penetration.

Gas permeability: a new quantitative method to assess endodontic leakage.

Aim: The aim of this study was to evaluate a new endodontic leakage measurement method.

Materials And Methods: Permeability was assessed measuring the gas flow passing through the root. Positive and negative tests were carried out to assess the validity of the method.