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Purpose: The host tissue reaction to the xenogeneic bone substitute Bio-Oss™ (Geistlich Biomaterials, Wolhousen, Switzerland) was investigated focusing on the participating inflammatory cells and implantation bed vascularization. Materials and Methods: Bio-Oss™ was implanted subcutaneously into CD1 mice for up to 60 days and analyzed by means of specialized histological and histomorphometrical techniques after explantation. Results: Bio-Oss™ induced within the first 15 days an early high vascularization combined with a marked presence of multinucleated giant cells. The latter cells were associated mainly with the smaller sized granules within the implantation bed. Toward the end of the study the number of multinucleated giant cells decreased while the tissue reaction to the larger granules was mainly mononuclear. Conclusion: The results of the present study showed that smaller xenogeneic bone substitute granules induce multinucleated giant cells, whereas the larger-sized ones became integrated within the implantation bed by means of a mononuclear cell-triggered granulation tissue. Obviously, the presence of multinucleated giant cells within biomaterial implantation beds is not only related to the type of synthetic bone substitute material, but also to the granule size of the “natural-based” xenogeneic bone substitute material. [ABSTRACT FROM AUTHOR]

In this article we extend the expression obtained by Kugel and Khomskii for cubic perovskites, where the transition metal ion has a 3d1 electronic configuration with threefold (3dt2g) orbital degeneracy. We derive an effective spin-orbital Hamiltonian by taking into account both the role of the oxygen on the bond between the transition metal ions and the role of the 3deg levels in superexchange processes, while no simplifications are done concerning the electron-electron interactions. A simple mean-field treatment yields a competition between an antiferromagnetic (AFM) and a ferromagnetic phase. The stability of these phases is driven by several parameters including the following: the ratio tp/ts=∣(pdπ)/(pdσ)∣ between π-type and σ-type electron hoppings, the charge transfer gap ΔCT, the exchange (Hund's) coupling, the crystal field Δ0 between the t2g and eg 3d orbitals, and the "pseudo" crystal field gap Δzxoxy between the oxygen 2p orbitals. The addition of the spin-orbit coupling is shown to be able to lead to a sensible reduction of the ordered magnetic moment in the AFM phase as well as the appearance of a weak ferromagnetic moment. [ABSTRACT FROM AUTHOR]

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

L’utilisation des gels plaquettaires en tant qu’adjuvants chirurgicaux est encore très récente, et elle souffre du manque d’investigations sérieuses quant à leurs propriétés biologiques. Ce constat met en évidence la nécessité de protocoles d’analyse rationalisés, reproductibles et fiables des résultats obtenus par adjonction de ces préparations. Face à l’absence totale de travaux sur le PRF (Platelet-Rich Fibrin), dont l’action sur le guidage du remodelage osseux est en théorie plus importante que celle d’une simple colle biologique à base de fibrine (cPRP : concentrated Platelet-Rich Plasma), nous avons entrepris une étude histologique de prélèvements osseux issus d’une série de neuf comblements de sinus réalisés avec de l’os allogénique Phœnix de TBF®, avec ou sans PRF. Après quatre mois de maturation, le tissu osseux greffé avec PRF a fini par acquérir une architecture quasiment superposable à celle obtenue à huit mois sans PRF. De plus, les quantités d’os néoformé sont équivalentes entre les deux protocoles. Ces résultats nous permettent d’envisager la diminution du temps de maturation des greffons avant implantation et la réalisation de greffes à l’aide de prélèvements osseux moins importants grâce à l’ajout de PRF. [Copyright &y& Elsevier]

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implantodontie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Platelet-rich fibrin (PRF) has had a marked impact on regenerative medicine due to its widespread ability to promote angiogenesis to defective tissues. Particularly in the dental field, evidence from randomized clinical trials has further shown that PRF facilitates greater soft-tissue regeneration when compared with hard tissues., Clinical Considerations: Recently, the fibrin-assisted soft-tissue promotion (FASTP) technique has been developed as a means to promote soft-tissue regeneration of mucogingival recessions utilizing PRF. Within the present case report, a 28-year-old male presented with multiple adjacent mucogingival recessions in the maxilla ranging in probing depths (1-3 mm) and gingival recessions (1-5 mm). For optimal regenerative outcomes, the use of advanced PRF (A-PRF; 1300 RPM for 8 min) has been utilized to enhance regenerative outcomes by fully taking advantage of the low-speed centrifugation concept (LSCC)., Conclusions: This case report highlights the latest surgical concepts, centrifugation protocols, and use of the LSCC to regenerate multiple adjacent mucogingival recessions in the esthetic zone., (© 2024 Wiley Periodicals LLC.)

Background: The development of malocclusion is related to various factor, many of which are still not fully explained. The steroid hormone, 1,25-dihydroxyvitamin D3, has pleiotropic effects. It plays a key role in skeletal metabolism and the control of cell repair by attaching to the nuclear vitamin D steroid receptor (VDR). This vitamin affects bone turnover through the processes of bone tissue formation and resorption via its action on cells of the osteoblastic and osteoclastic lineage, exerts a modulating effect on the immune system, and is involved in the regulation of cell proliferation and differentiation. The role of vitamin D3 (VD3) and its receptor polymorphisms is a rarely studied topic in dentistry. Due to the proven influence on bone turnover processes and immune responses, the main research topic is its relation to periodontal diseases, but so far, its role in the formation and development of malocclusions has not been assessed., Objectives: This study aimed to assess the association of selected VDR polymorphisms: Cdx2 (rs11658820), TaqI (rs7975232), BsmI (rs1544410), ApaI (rs7975232), and FokI (rs2228570) with the development of malocclusions., Material and Methods: A prospective observational study was performed. The examination consisted of a medical interview, intraand extraoral orthodontic diagnosis, alginate impression, cone beam computed tomography (CBCT), and venous blood sample to obtain genomic DNA and assess VDR polymorphisms., Results: The rs11658820 polymorphism causes an almost 4-fold increase in the probability of the presence of a malocclusion. GT and TT genotypes of rs7975232 are also associated with a similar risk - almost 6 and almost 5 times higher, respectively. In turn, the effect of the rs2228570-AG and GG genotype polymorphisms on the occurrence of transversal anomalies was demonstrated (odds ratio (OR) = 8.46 and OR = 6.92, respectively)., Conclusions: The association of individual polymorphisms with specific malocclusions should be carefully assessed, especially since some trends have been indicated.

Based on the evidence of a significant communication and connection pathway between the bone and immune systems, a new science has emerged: osteoimmunology. Indeed, the immune system has a considerable impact on bone health and diseases, as well as on bone formation during grafts and its stability over time. Chronic inflammation induces the excessive production of oxidants. An imbalance between the levels of oxidants and antioxidants is called oxidative stress. This physio-pathological state causes both molecular and cellular damage, which leads to DNA alterations, genetic mutations and cell apoptosis, and thus, impaired immunity followed by delayed or compromised wound healing. Oxidative stress levels experienced by the body affect bone regeneration and maintenance around teeth and dental implants. As the immune system and bone remodeling are interconnected, bone loss is a consequence of immune dysregulation. Therefore, oral tissue deficiencies such as periodontitis and peri-implantitis should be regarded as immune diseases. Bone management strategies should include both biological and surgical solutions. These protocols tend to improve immunity through antioxidant production to enhance bone formation and prevent bone loss. This narrative review aims to highlight the relationship between inflammation, oxidation, immunity and bone health in the oral cavity. It intends to help clinicians to detect high-risk situations in oral surgery and to propose biological and clinical solutions that will enhance patients' immune responses and surgical treatment outcomes.