A scoping review of graphene-based biomaterials for in vivo bone tissue engineering.

The growing demand for more efficient materials for medical applications brought together two previously distinct fields: medicine and engineering. Regenerative medicine has evolved with the engineering contributions to improve materials and devices for medical use. In this regard, graphene is one of the most promising materials for bone tissue engineering and its potential for bone repair has been studied by several research groups. The aim of this study is to conduct a scoping review including articles published in the last 12 years (from 2010 to 2022) that have used graphene and its derivatives (graphene oxide and reduced graphene) in preclinical studies for bone tissue regeneration, searching in PubMed/MEDLINE, Embase, Web of Science, Cochrane Central, and clinicaltrials.gov (to confirm no study has started with clinical trial). Boolean searches were performed using the defined key words "bone" and "graphene", and manuscript abstracts were uploaded to Rayyan, a web-tool for systematic and scoping reviews. This scoping review was conducted based on Joanna Briggs Institute Manual for Scoping Reviews and the report follows the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Extension for Scoping Reviews (PRISMA-ScR) statement. After the search protocol and application of the inclusion criteria, 77 studies were selected and evaluated by five blinded researchers. Most of the selected studies used composite materials associated with graphene and its derivatives to natural and synthetic polymers, bioglass, and others. Although a variety of graphene materials were analyzed in these studies, they all concluded that graphene, its derivatives, and its composites improve bone repair processes by increasing osteoconductivity, osteoinductivity, new bone formation, and angiogenesis. Thus, this systematic review opens up new opportunities for the development of novel strategies for bone tissue engineering with graphene.

Cell-Friendly Chitosan-Xanthan Gum Membranes Incorporating Hydroxyapatite Designed for Periodontal Tissue Regeneration.

In this work, a simple method was proposed to produce dense composite polysaccharide-based membranes to be used for guided tissue and guided bone regeneration. The mucoadhesive polysaccharides chitosan (C) and xanthan gum (X) were used to produce polyelectrolyte-based complex membranes. Hydroxyapatite (HA) was added to the formulation as a potential drug carrier, in C:X:HA mass proportions equal to 1:1:0.4, 1:1:2, and 1:1:10, and also to improve membranes bioactivity and biomimetic properties. FTIR analysis indicated successful incorporation of HA in the membranes and XRD analysis showed that no changes in the HA crystalline structure were observed after incorporation. The residual mass evaluated by TGA was higher for the formulation produced at the proportion 1:1:10. The membranes produced showed asymmetrical surfaces, with distinct roughness. Increasing the HA concentration increased the surface roughness. Greater in vitro proliferation of dental pulp mesenchymal stem cells was observed on the surface of the membrane with 1:1:10 C:X:HA proportion. However, the 1:1:2 formulation showed the most adequate balance of mechanical and biological properties. These results suggest that adding HA to the membranes can influence mechanical parameters as well as cell adhesion and proliferation, supporting the potential application of these materials in regenerative techniques and the treatment of periodontal lesions.

Simplificando o tratamento por meio da utilização de implantes curtos: relato de caso / Short implant usage simplifying the treatment: case report

A reabsorção óssea do rebordo alveolar frequentemente gera a necessidade de cirurgias reconstrutoras para aumentar seu tamanho e tornar possível a instalação de implantes. Estes procedimentos cirúrgicos são mais onerosos e invasivos do que a terapia convencional, sendo fatores que diminuem a aceitação do paciente. O tratamento de rebordos edêntulos de altura óssea reduzida com implantes curtos já foi associado no passado a menores taxas de sucesso. Entretanto, estudos recentes demonstram resultados similares aos implantes de comprimento maior, sendo esta melhora atribuída principalmente ao aperfeiçoamento da micro e macroestrutura do implante, ao emprego de uma técnica cirúrgica adequada e curva de aprendizado do cirurgião. Este artigo tem como propósito fazer uma revisão da literatura sobre a viabilidade da utilização de implantes curtos e apresentar um caso onde se pôde simplificar o tratamento sem a aplicação de técnicas cirúrgicas regenerativas mais avançadas

Reconstructive surgeries are usually needed in residual ridges with reduced bone height to make long implants placement possible. These procedures are invasive and have a high cost, being factors that decrease patient acceptation of the therapy. The treatment with short implants was related with high levels of failure in the past. Nowadays recent studies show similar results when compared to longer implants, the reason for that was associated with improvement of the micro and macrostructure of the implants, adequate surgical technique and operators learning curve. The aim of this paper is to make a literature review about the viability for the use of short implants and report a clinical case where the treatment was simplified without the use of more advanced regenerative surgeries

Infecção de sítios periimplantares por microrganismos periodontopatogênicos: relato de caso / Peri-implant site infection by periodontopathogenic microorganisms: a case report

A colonização do sítio periimplantar por microrganismos periodontopatogênicos está relacionada à inflamação da mucosa na região, condição denominada mucosite, que pode evoluir para periimplantite em caso de perda óssea ao redor do implante, sendo considerada a causa mais frequente de perda de implantes. O objetivo deste trabalho é, através de uma revisão de literatura e da descrição de um caso clínico, identificar os prováveis nichos destes microrganismos.

Colonization of periimplant sites by periodontopathogens is associated with periimplant mucosa inflammation, denominated mucositis, which can evolutes to periimplantitis when marginal bone loss occurs around the implant. This condition is considered the most frequent cause of implant failure. The aim of this study is, through a literature review and a clinical case presentation, to evaluatethe probable originally sites of these microorganisms.