Poly-3-hydroxybutyrate-silver nanoparticles membranes as advanced antibiofilm strategies for combatting peri-implantitis.

Dental implant success is threatened by peri-implantitis, an inflammation leading to implant failure. Conventional treatments struggle with the intricate microbial and host factors involved. Antibacterial membranes, acting as barriers and delivering antimicrobials, may offer a promising solution. Thus, this study highlights the potential of developing antibacterial membranes of poly-3-hydroxybutyrate and silver nanoparticles (Ag Nps) to address peri-implantitis challenges, discussing design and efficacy against potential pathogens. Electrospun membranes composed of PHB microfibers and Ag Nps were synthesized in a blend of DMF/chloroform at three different concentrations. Various studies were conducted on the characterization and antimicrobial activity of the membranes. The synthesized Ag Nps ranged from 4 to 8 nm in size. Furthermore, Young's modulus decreased, reducing from 13.308 MPa in PHB membranes without Ag Nps to 0.983 MPa in PHB membranes containing higher concentrations of Ag Nps. This demonstrates that adding Ag Nps results in a less stiff membrane. An increase in elongation at break was noted with the rise in Ag Nps concentration, from 23.597 % in PHB membranes to 60.136 % in PHB membranes loaded with Ag Nps. The antibiotic and antibiofilm activity of the membranes were evaluated against Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans, and Candida albicans. The results indicated that all PHB membranes containing Ag Nps exhibited potent antibacterial activity by inhibiting the growth of biofilms and planktonic bacteria. However, inhibition of C. albicans occurred only with the PHB-Ag Nps C membrane. These findings emphasize the versatility and potential of Ag Nps-incorporated membranes as a multifunctional approach for preventing and addressing microbial infections associated with peri-implantitis. The combination of antibacterial and antibiofilm properties in these membranes holds promise for improving the management and treatment of peri-implantitis-related complications.

In Vivo Osteogenic Potential of Biomimetic Hydroxyapatite/Collagen Microspheres: Comparison with Injectable Cement Pastes.

The osteogenic capacity of biomimetic calcium deficient hydroxyapatite microspheres with and without collagen obtained by emulsification of a calcium phosphate cement paste has been evaluated in an in vivo model, and compared with an injectable calcium phosphate cement with the same composition. The materials were implanted into a 5 mm defect in the femur condyle of rabbits, and bone formation was assessed after 1 and 3 months. The histological analysis revealed that the cements presented cellular activity only in the margins of the material, whereas each one of the individual microspheres was covered with osteogenic cells. Consequently, bone ingrowth was enhanced by the microspheres, with a tenfold increase compared to the cement, which was associated to the higher accessibility for the cells provided by the macroporous network between the microspheres, and the larger surface area available for osteoconduction. No significant differences were found in terms of bone formation associated with the presence of collagen in the materials, although a more extensive erosion of the collagen-containing microspheres was observed.

Inervación sensitiva y crecimiento mandibular: propuesta de modelo experimental para acceso quirúrgico al nervio alveolar inferior preservando estructuras musculoesqueléticas en conejo New Zealand White pos-destetados / Sensitive inervation and mandibular growth: a novel proposal for a surgical access to inferior alveolar nerve preserving musculoskeletal health in post-weaned New Zealand White rabbit

Numerosos estudios reflejan vínculos entre la inervación sensitiva y el desarrollo de la estructura ósea mandibular. Con la finalidad de obtener un modelo in vivo para estudiar el efecto de la alteración de la inervación sensitiva sobre el crecimiento mandibular, se propone un acceso quirúrgico al nervio alveolar inferior que evita dañar las estructuras músculo-esqueléticas consideradas esenciales en el crecimiento craneofacial. El modelo utilizado fue el conejo New Zealand White post-destetado. Primera etapa: se realizó un estudio mediante disección anatómica para elegir una vía de acceso quirúrgico. Se eligió el acceso por la región submandibular. Desde esta zona, se accede al nervio en su punto de ingreso al canal mandibular, entre la rama mandibular y el músculo pterigoideo medial. Segunda etapa: Se utilizaron 12 especímenes a los cuales se aplicó el procedimiento quirúrgico diseñado con ayuda y supervisión veterinaria. Posteriormente, los animales fueron controlados bajo condiciones estandarizadas durante 90 días. Se evaluaron los siguientes aspectos: 1. Progreso de curación de herida quirúrgica; 2. Se utilizó un protocolo de valoración de aplicabilidad del diseño quirúrgico basado en las directrices generales de Morton y Griffitt para detección de dolor y disconfort en animales de experimentación y las directrices específicas del Southwestern Medical Center para evaluación de dolor y disconfort en conejos. Según los parámetros analizados, no se observaron valores indicadores de inaplicabilidad del protocolo propuesto. El progreso de la herida quirúrgica se consideró normal. Estudios que analizan la participación de la inervación sensitiva en aspectos fisiológicos mandibulares muestran vías quirúrgicas para modificar la estructura nerviosa que implican alteraciones musculoesqueléticas. El procedimiento aquí presentado preserva estas estructuras y es bien tolerado por este animal en etapas tempranas de crecimiento. En consecuencia resulta una alternativa ...

Numerous studies have shown links between sensory inervation and mandibular bone development. In order to obtain an in vivo model to study the effect of altered sensory innervation on mandibular growth, a surgical approach for the inferior alveolar nerve transsection is proposed. This procedure avoids damage to muscular or skeletal structures that are considered essential in craniofacial growth. New Zealand White rabbits post-weaning were used. First stage: morphological study by anatomical dissection for choosing a surgical portal. The access chosen for the intervention was the submandibular region. From this area, it is possible to access the point where the nerve is entering into the mandibular canal, between the Ramus Mandibular and the Medial Pterygoid Muscle. Second stage: 12 specimens were submitted to the proposed surgical procedure under veterinary supervision. Subsequently, the animals were monitored under standard conditions for 90 days. The following aspects were evaluated: 1. Surgical wound healing; 2. A double protocol for assessing applicability of surgical design was used. The first was based on Morton and Griffitt general guidelines to detect pain and discomfort in experimental animals and the second was based on the Southwestern Medical Center guidelines for evaluation of pain and discomfort in rabbits. The progress of the surgical wound was considered normal. According to the parameters analyzed, the values obtained indicate that the protocol is applicable to the surgical procedure. Studies examining the contribution of sensory inervation concerning physiological aspects of the mandibular bone employ surgical methods to modify the nervous structure, thus provoking musculoskeletal disorders. The procedure presented here preserves these structures and is well tolerated by the animal in early stages of growth. For that reason, this method is a feasible alternative for studying the participation of sensory innervation in mandibular growth.