Ivan Panayotov

• DDS, PhD
• Professor (Associate) at Université de Montpellier

Photobiomodulation (PBM) therapy is a continuously growing approach to stimulating healing and reducing inflammation and pain. However, its effects in the fields of regenerative medicine and tissue engineering are still under investigation. Studying PBM effects on the regenerative capacity of zebrafish can allow the application of novel clinical ap...

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...

There is a lack of evidence-based reviews on the effects of laser irradiation on blood coagulation in the literature, despite a large number of clinical trials. We therefore evaluated the available evidence on laser irradiation parameters used in coagulation of blood to optimize physical parameters. We performed a literature search for recent scien...

Introduction: The functionalization of titanium (Ti) and titanium alloys (Ti6Al4V) implant surfaces via material-specific peptides influence host/biomaterial interaction. The impact of using peptides as molecular linkers between cells and implant material to improve keratinocyte adhesion is reported. Results: The metal binding peptides (MBP-1, MBP-...

Introduction: This review summarizes the available recent literature on different mechanisms and parameters of pulsed ultrasound (US) that have been used during orthodontic treatments to prevent and repair root resorption. Areas covered: A literature search was conducted between January (2002) and September (2022) in the following databases: Pub...

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...

Objective: The tufts of human dental enamel are structures located at the enamel-dentin junction and whose origin has not been clearly established. Although studies have highlighted their protein content and hypomineralization, none has been able to shed light on their 3D structure. The aim of this study was to reveal the whole structure using high...

Objective The aim of this article is to analyze the chemical mapping of tufts and spindles of the human dental enamel using confocal Raman microscopy measuring length, structuration and composition of spindles and tufts. Design we used Raman diffusion, based on the interaction between photons and optic phonons, to reveal chemical bound. Adult mola...

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...

Following the basis of tissue engineering (Cells-Scaffold-Bioactive molecules), regenerative endodontic has emerged as a new concept of dental treatment. Clinical procedures have been proposed by endodontic practitioners willing to promote regenerative therapy. Preserving pulp vitality was a first approach. Later procedures aimed to regenerate a va...

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 fluor...

Polyetheretherketone (PEEK) is a polyaromatic semi-crystalline thermoplastic polymer with mechanical properties favorable for bio-medical applications. Polyetheretherketone forms: PEEK-LT1, PEEK-LT2, and PEEK-LT3 have already been applied in different surgical fields: spine surgery, orthopedic surgery, maxillo-facial surgery etc. Synthesis of PEEK...

Proper treatment of dental caries demands detection of carious lesions at an early stage and a minimal invasive cavity preparation to preserve the maximum tooth structure. Various devices use fluorescence for caries detection via recording the red fluorescence generated by dentin caries under illumination. The aim of this study was to evaluate the...

Antibacterial surfaces have been in the focus of research for years, driven by an unmet clinical need to manage an increasing incidence of implant-associated infections. The use of silver has become a topic of interest because of its proven broad-spectrum antibacterial activity and track record as a coating agent of soft tissue implants and cathete...

Multiphoton confocal microscopy and nonlinear spectroscopy are used to investigate the caries process in dentin. Although dentin is a major calcified tissue of the teeth, its organic phase comprises type I collagen fibers. Caries drive dentin demineralization and collagen denaturation. Multiphoton microscopy is a powerful imaging technique: the bio...

The EU directive 2010/63/EU on the protection of animals used for scientific purpose focused on reducing the number of animals and refinement of breeding. Animal studies are necessary to protect human health. Lots of animal models exist to study bone regeneration but a reliable, well reproducible and relatively inexpensive model with the possibilit...

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 modificat...

The way cells explore their surrounding extracellular matrix (ECM) during development and migration is mediated by lamellipodia at their leading edge, acting as an actual motor pulling the cell forward. Lamellipodia are the primary area within the cell of actin microfilaments (filopodia) formation. In this work, we report on the use of porous silic...

Further development of biomaterials is expected as advanced therapeutic products must be compliant to good manufacturing practice regulations. A spraying method for building-up polyelectrolyte films followed by the deposition of dental pulp cells by spraying is presented. Physical treatments of UV irradiation and a drying/wetting process are applie...

The aim of this study was to evaluate the porphyrin involvement in the red fluorescence observed in dental caries with Soprolife (R) light-induced fluorescence camera in treatments mode (SOPRO, ACTEON Group, La Ciotat, France) and Vistacam (R) camera (DURR DENTAL AG, Bietigheim-Bissingen, Germany). The International Caries Detection and Assessment...

In regenerative medicine, stem cell-based therapy often requires a scaffold to deliver cells and/or growth factors to the injured site. Porous silicon (pSi) is a promising biomaterial for tissue engineering as it is both non-toxic and bioresorbable. Moreover, surface modification can offer control over the degradation rate of pSi and can also promo...

Objective: Dental education is a field of a great number of challenges, requirements and stress situations. Students must have different kinds of competence such as academic, clinical, behavioral and emotional. The high levels of stress are related with physical symptoms, psychological distress, emotional exhaustion and learning failure. The stress...

Preservation of natural tooth structure requires early detection of the carious lesion and is associated with comprehensive patient dental care. Processes aiming to detect carious lesions in the initial stage with optimum efficiency employ a variety of technologies such as magnifying loupes, transillumination, light and laser fluorescence (QLF(®) a...

Confocal Raman microscopy is a noninvasive, label-free imaging technique used to study apoptosis of live MCF-7 cells. The images are based on Raman spectra of cells components, and their apoptosis is monitored through diffusion of cytochrome c in cytoplasm. K-mean clustering is used to identify mitochondria in cells, and correlation analysis provid...

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 signal...

Dental implant stability is dependent of the quality of the epithelial sealing around abutment. We developed bi-functional peptides as linkers between cell and metal. Metal specific 12-mer peptides were selected by phage display and their adhesion forces to implant surfaces investigated by Atomic force microscopy (AFM). On these two peptides cell s...

Short Communication selected from the Oral Presentations of the 56th Congress of the Groupèment International pour la Recherche Scientifique en Stomatologie et Odontologie, Peñafiel (Portugal) May 2012.

Short Communication selected from the Oral Presentations of the 56th Congress of the Groupèment International pour la Recherche Scientifique en Stomatologie et Odontologie, Peñafiel (Portugal) May 2012.

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, a...

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. During their training dental students express high levels of stress and considerable stress-related s...

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 obse...

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 pentosid...

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 t...

A fluorescence based method for dental caries detection was recently developed. Objectives: The aim of this study was to investigate correlations between variation of dental hard tissues fluorescence and structural changes during dentin demineralization. Methods: Tooth longitudinal slices with a thickness up to 0.5mm were prepared from freshly extr...

Objective: To study and compare the attitudes of dental medicine students and practicing dentists towards the treatment of drug addicted patients in Plovdiv, Bulgaria. Methods: The research is a part of the project Oral Health of Drug Addicted Patients, funded by a grant from the Medical University-Plovdiv. Data has been collected by an anonymous s...

Cell spray deposition techniques for the needs of tissue engineering are being actively developed during the last few years. They permit easier deposition of cells on surfaces with complex configurations, creation of cell multilayers and three-dimensional cell cultures. Objectives: The aim of the present study was to optimize the parameters of cell...

Non-linear optical microscopy (NLOM) is an effective method to follow pathological processes involving collagen fibrosis or collagen destruction. In particular, the intensity of the second harmonic generation (SHG) signal depends on the structure and orientation of the collagen fibers. In this work, we have used two-photon fluorescence (2PEF) and S...