From Coagulation to Oral Surgery Application: Platelets in Bone Regeneration

International audienceThe complexity of the treatment of tissue lesions, particularly bone lesions, in regenerative medicine depends on the origin of the substance loss (traumatic, tumoral, infectious, etc.), its size and mechanical requirements. In the field of dental surgery, the need to ensure rapid regeneration of injured bone tissue for periodontal, post-extractional or pre-implant corrective surgery leads dental surgeons to have a large number of biomaterials in their therapeutic arsenal. The mineral materials are most often used because of their chemical composition which is close to bone’s mineral phase. They also present a resorption time in agreement with the time of formation of new bone.However their benefits are inconstant and the need of new bioactive structures, well accepted by the host, and favoring tissue healing has grown. Here is the place for platelet concentrates such as Platelet Rich Plasma (PRP) and Platelet Rich Fibrin (PRF) which are rich in growth factors, cytokines and others proteins. PRF became the most commonly used in the last decade as it is easier to handle with its polymerized form which mimics an extracellular matrix favorable to cell proliferation and differentiation. A new option, called platelet lysate, has recently been highlighted in the general field of tissue regeneration and has the advantage of making platelet’s content directly available. Proteins concentrations are increased in these products even if their liquid form complicates their use in daily practice. This mini-review sums up the main clinical interests for the use of platelet concentrates and the new perspectives in the field of alveolar bone regeneration especially with platelet lysate

From Coagulation to Oral Surgery Application: Platelets in Bone Regeneration

The complexity of the treatment of tissue lesions, particularly bone lesions, in regenerative medicine depends on the origin of the substance loss (traumatic, tumoral, infectious, etc.), its size and mechanical requirements. In the field of dental surgery, the need to ensure rapid regeneration of injured bone tissue for periodontal, post-extractional or pre-implant corrective surgery leads dental surgeons to have a large number of biomaterials in their therapeutic arsenal. The mineral materials are most often used because of their chemical composition which is close to bone’s mineral phase. They also present a resorption time in agreement with the time of formation of new bone.However their benefits are inconstant and the need of new bioactive structures, well accepted by the host, and favoring tissue healing has grown. Here is the place for platelet concentrates such as Platelet Rich Plasma (PRP) and Platelet Rich Fibrin (PRF) which are rich in growth factors, cytokines and others proteins. PRF became the most commonly used in the last decade as it is easier to handle with its polymerized form which mimics an extracellular matrix favorable to cell proliferation and differentiation. A new option, called platelet lysate, has recently been highlighted in the general field of tissue regeneration and has the advantage of making platelet’s content directly available. Proteins concentrations are increased in these products even if their liquid form complicates their use in daily practice. This mini-review sums up the main clinical interests for the use of platelet concentrates and the new perspectives in the field of alveolar bone regeneration especially with platelet lysate

Thermogravimetric study of the behaviour of organic and inorganic polymers contained in four dental resin-based composites

The composition of dental resin-based composite (RBC) matrix is partly responsible for many clinical failures in restorations, which may come from dimensional variation or instability in a wet environment. The objective of this study is therefore to evaluate the thermal stability over time of four dental RBC with different matrices. Silicone cylinders were filled with four different materials and then photopolymerized. To simulate ageing in the buccal environment, half of the samples were placed in a dark place at 37°C for 45 days in sealed compartments containing 2 ml of water. All the RBC produced were subjected to thermogravimetric analysis to measure the loss of mass as a function of temperature. Bis-GMA-based resins and Ormocer materials have similar curves before and after soaking in humid atmosphere. The curves of the UDMA resin are different before and after water ageing, meaning that water imbibition has modified the structure of the composite and its degradation. Even if many curves are similar within the same RBC at different polymerization times or at different pre- and post-ageing times, it is rare to observe a common kinetics between two different composites. Our results show good wet stability of polymerized dental RBC according to the manufacturer’s instructions, although the UDMA-based materials show more variation. It therefore seems that Ormocer resin composite with mass placement have ageing properties that can compete with those of conventional composites whereas those incremented on 2 mm layers are more sensitive to the time necessary for polymerization

Le rôle de l'anatomie dentaire dans l'esthétique du visage

TOULOUSE3-BU Santé-Centrale (315552105) / SudocSudocFranceF

La contraction de polymérisation des composites utilisés en méthode directe

Introduit à des fins esthétiques dans un premier temps, les composites dentaires sont utilisés, de nos jours, pour restaurer des cavités postérieures où les propriétés mécaniques priment. La polymérisation d'un composite s'accompagne d'une rétraction de ce dernier. Cette rétraction de prise et les contraintes qui en découlent, entraînent de nombreuses conséquences sur le matériau et la dent (récidives de caries, formation d'un hiatus périphérique ), mettant en péril la restauration.TOULOUSE3-BU Santé-Centrale (315552105) / SudocSudocFranceF

From Coagulation to Oral Surgery Application: Platelets in Bone Regeneration

International audienceThe complexity of the treatment of tissue lesions, particularly bone lesions, in regenerative medicine depends on the origin of the substance loss (traumatic, tumoral, infectious, etc.), its size and mechanical requirements. In the field of dental surgery, the need to ensure rapid regeneration of injured bone tissue for periodontal, post-extractional or pre-implant corrective surgery leads dental surgeons to have a large number of biomaterials in their therapeutic arsenal. The mineral materials are most often used because of their chemical composition which is close to bone’s mineral phase. They also present a resorption time in agreement with the time of formation of new bone.However their benefits are inconstant and the need of new bioactive structures, well accepted by the host, and favoring tissue healing has grown. Here is the place for platelet concentrates such as Platelet Rich Plasma (PRP) and Platelet Rich Fibrin (PRF) which are rich in growth factors, cytokines and others proteins. PRF became the most commonly used in the last decade as it is easier to handle with its polymerized form which mimics an extracellular matrix favorable to cell proliferation and differentiation. A new option, called platelet lysate, has recently been highlighted in the general field of tissue regeneration and has the advantage of making platelet’s content directly available. Proteins concentrations are increased in these products even if their liquid form complicates their use in daily practice. This mini-review sums up the main clinical interests for the use of platelet concentrates and the new perspectives in the field of alveolar bone regeneration especially with platelet lysate

Anatomie dentaire : du fondamental à la clinique

International audienceL'objectif de l'ouvrage est d'apporter aux chirurgiens-dentistes et aux stomatologistes les données anatomiques indispensables à la réalisation de leurs actes chirurgicaux, sans oublier le soutien anatomique apporté aux prothésistes dentaires. L'ouvrage s'adresse aussi bien aux étudiants qu'aux praticiens. Les premiers pourront apprendre les caractéristiques fondamentales de l'anatomie et entrevoir les fonctions qui s'y rapportent. Les praticiens, quant à eux, pourront avec l'expérience acquise en pratique quotidienne revenir aux sources pour mieux comprendre l'importance de l'agencement inter-arcades au cours des traitements. Ce livre comprend trois grands chapitres : une première partie fondamentale basée sur la description des dents humaines adultes, une deuxième partie plus clinique alliant anatomie et fonction, enfin une troisième partie mettant en avant les notions d'esthétiques liées à la présence des dents. Il a été rédigé avec un souci constant de mise en avant de l'iconographie et d'une grande praticité d'utilisation par son lecteur

Anatomie dentaire : du fondamental à la clinique

International audienceL'objectif de l'ouvrage est d'apporter aux chirurgiens-dentistes et aux stomatologistes les données anatomiques indispensables à la réalisation de leurs actes chirurgicaux, sans oublier le soutien anatomique apporté aux prothésistes dentaires. L'ouvrage s'adresse aussi bien aux étudiants qu'aux praticiens. Les premiers pourront apprendre les caractéristiques fondamentales de l'anatomie et entrevoir les fonctions qui s'y rapportent. Les praticiens, quant à eux, pourront avec l'expérience acquise en pratique quotidienne revenir aux sources pour mieux comprendre l'importance de l'agencement inter-arcades au cours des traitements. Ce livre comprend trois grands chapitres : une première partie fondamentale basée sur la description des dents humaines adultes, une deuxième partie plus clinique alliant anatomie et fonction, enfin une troisième partie mettant en avant les notions d'esthétiques liées à la présence des dents. Il a été rédigé avec un souci constant de mise en avant de l'iconographie et d'une grande praticité d'utilisation par son lecteur

Survival of directly placed ormocer-based restorative materials: A systematic review and meta-analysis of clinical trials

International audienceObjectivesIn-vitro experiments on ormocers (ORganically MOdified CERamics) have provided controversial results. Consequently, the objectives of this meta-analysis were to (1) compare clinical performances of first generation ormocers versus conventional composite restorations, (2) explore the influence of various clinical factors and the impact of the quality of studies on published results.MethodsThe following databases were explored until 2017/01/08: Ovid MEDLINE In-Process, Pubmed, CENTRAL, HTA, DARE, LILACS and Google Scholar.Studies of more than two years with quantitative comparisons between ormocers and control groups were selected. Outcome was the failure of a restoration (need to repair, remove or replace). Multivariate random-effects Poisson’s regression was used to obtain a summary estimate.Results75% of the 8 included trials concerned Class I/II restorations. Although non-significant, the global failures were higher for ormocers (0.22 [−0.16; 0.61]). For Class I/II restorations, a significantly higher sensitivity was observed for ormocer-based materials compared to other composites (0.75 [0.01; 1.50]). An increase of the number of restorations per patient was associated with higher marginal adaptation failures for ormocers in Class I/II obturations (0.59 [0.11; 1.08]).SignificanceThis study did not identify clear advantages of using the first generation of ormocer-based fillings rather than conventional composites. Given the recent development of new, dimethacrylate-diluent-free ormocer matrices, potentially more stable and resistant, new randomized clinical trials should be developed comparing this new family of pure ormocers with current composites